The incidence of hypoxemia during painless gastrointestinal endoscopy remains a matter of concem. To date, there is no recognized simple method to predict hypoxemia in digestive endoscopic anesthesia. The NoSAS  questionnaire, an objective and simple assessment scale used to assess obstructive sleep apnea (OSA), combined with the modified Mallampati grade (MMP), may have certain screening value. This combination may allow anesthesiologists to anticipate, manage, and consequently decrease the occurrence of hypoxemia.This study was a prospective observational trial. The primary endpoint was the incidence of hypoxaemia defined as pulse oxygen saturation (SpO2) < 95% for 10 s. A total of 2207 patients admitted to our hospital for painless gastrointestinal endoscopy were studied. All patients were measured for age, height, weight, body mass index, neck circumference, snoring, MMP, and other parameters. Patients were divided into hypoxemic and non-hypoxemic groups based on the SpO2. The ROC curve was plotted to evaluate the screening value of the NoSAS questionnaire separately and combined with MMP for hypoxemia. The total NoSAS score was evaluated at cut-off points of 8 and 9.P < 0.001, 95% CI: 0.708–0.759). With a NoSAS score ≥ 9 as a critical value, the sensitivity for hypoxemia was 36.50%, the specificity rose to 96.16%, and the area under the ROC was 0.663 . With the NoSAS Score combined with MMP for analysis, the sensitivity was 78.4%, the specificity was 84%, and the area under the ROC was 0.859 .With a NoSAS score ≥ 8 as the critical value for analysis, the sensitivity for hypoxemia was 58.3%, the specificity was 88.4%, and the area under the ROC was 0.734 (As a new screening tool, the NoSAS questionnaire is simple, convenient, and useful for screening hypoxemia. This questionnaire, when paired withMMP, is likely to be helpful for the screening of hypoxemia. The purpose of gastrointestinal endoscopy is to achieve a thorough examination of the gastrointestinal tract in the safest and most comfortable manner possible. Although drug-induced sedation in endoscopic procedures improves patient comfort and facilitates endoscopic performance , 2, airwPrevious studies have reported the incidence of hypoxemia during digestive endoscopy to range from 5.3 to 50% , 8.The pUnfortunately, there is no simple method for predicting hypoxemia during digestive endoscopic anesthesia. Instead, the method of assessing difficult airways in the operating room has been adopted, with other potentially relevant factors such as the position of the patient, endoscopic operation, bite placement, and other factors being ignored. Nonetheless, a single test that provides a simple, precise, and dependable prediction of hypoxemia is needed.According to our preliminary experiment, patients who developed hypoxemia had a higher BMI and larger neck circumference. Interestingly, these two physical indicators are thought to correlate with obstructive sleep apnea (OSA) severity . Under sA single clinical indicator, especially a highly subjective one, may be more accurate when combined with other, more objective indices. The modified Mallampati grade (MMP) is generally used to describe the relative relationship between the body of the tongue and the soft palate. Clinically, it is often used to identify difficult airways and still holds significant value among new predictors in the assessment of difficult laryngoscopy . StudiesHowever, whether it can be used to diagnose and evaluate hypoxemia remains unclear. Therefore, we aimed to evaluate the value of the NoSAS questionnaire combined with MMP in screening for hypoxemia during routine sedation for gastrointestinal endoscopy.Our study population was selected from among a prospective cohort of patients who underwent gastrointestinal endoscopy at the First Affiliated Hospital of Nanjinng Medical University. Patients who underwent these procedures between May 2020 and November 2020 were enrolled in the study. The study was approved by the hospital ethics committee . Patients were classified as hypoxemic (384 cases) or non-hypoxemic (1823 cases) based on oxygen saturation below 95%.The included patients were ≥ 18 years old, had American Society of Anesthesiologists (ASA) physical status classification scores of I-III, and were scheduled for gastrointestinal endoscopy. Patients scheduled for endoscopic retrograde cholangiopancreatography and procedures performed under planned tracheal intubation, pregnant women, and emergency patients were excluded from the study.The recorded patient variables included sex, age, ASA physical status, height, weight, neck length, history of snoring, and MMP.NoSAS questionnaire: All patients were instructed to complete the questionnaires provided to them by their anesthesiologist prior to examination. The questionnaire included the following items, along with the associated score values: neck circumference > 40 cm, 4 points; BMI between 25 and 30, 3 points; BMI ≥ 30, 5 points; snoring, 2 points; age > 55, 4 points; male sex, 2 points. A a threshold of 8 points or more indicates a high risk of OSA Table  12]..12].The MMP consisted of four classes: Class I, everything visible (tonsillar pillars); Class II, fully visible uvula; Class III, only the soft palate and base of the uvula visible; and Class IV, the soft palate not visible. MMP is a comprehensive assessment; the higher the grade, the more severe the airway stenosis.All patients remained in the left lateral position with their knees bent after admission and were monitored using continuous electrocardiography, heart rate, pulse oximetry, and noninvasive blood pressure monitoring during the procedure. Supplemental oxygen using double nasal catheters  was provided to all patients. A trained professional was responsible for the maintenance of sedation and patient monitoring while using propofol. The induction dose of propofol was 1–2 mg/kg . Upon loss of patient responses to verbal prompting, disappearance of the eyelash reflex, and absence of body motion response after firm pressing of the back edge of the mandibular branch, the digestive endoscopist was cleared to begin the operation. Propofol was added intraoperatively according to the patient's pain response, with supplementary doses consisting of 10–20 mg. In the case of SPO2 < 95% lasting more than 10 s, the anesthesiologists provider performed the necessary airway maneuver, which involved increase oxygen flow by opening the patient’s mouth. If the above measures proved ineffective, the operation was ceased, place the nasopharyngeal or oropharyngeal airway, or oxygen inhalation through the mask, and assist breathing  curve was plotted to evaluate the screening value of the NoSAS questionnaire alone versus the MMP combined with the NoSAS questionnaire. Adjusted odds ratios and 95% confidence intervals (CIs) were calculated. All tests were two-sided at a significance level of 0.05.Overall, 2207 patients, including 1136 men and 1071 women, were enrolled in this study. Of these, 384 (17.4%) experienced hypoxemia. The median age was 55 years (44-63 years) in the non-hypoxemic group and 57 years (48-65 years) in the hypoxemic group. According to the NoSAS questionnaire, the proportion of patients with NoSAS ≥ 8 was 11.6% and 58.3% in the non-hypoxemic and hypoxemic groups, respectively. According to MMP, 1644 patients were grade 1, 497 patients were grade 2, and 66 patients were grade 3. There was no difference in sex or ASA classification between the two groups   (Table 8) Table . The resMajor complications of airway management are still a matter of concern, and hypoxemia remains the most common cause of death during anesthesia . Non-traP < 0.05). The frequency of MMP > 2 was higher, and more than 50% of the patients had a history of snoring (P < 0.05). It was not logistically feasible to perform a sleep study on all patients undergoing endoscopy, so we identified patients as having a high or low risk for sleep apnea based on the NoSAS questionnaire to explore whether people at high risk for sleep apnea were more likely to develop hypoxemia.Previous studies have confirmed that patients with oxygen desaturation under conscious sedation may be considered for sleep apnea screening . Our preAt present, many scales are used in clinical screening for OSA, such as the STOP-BANG questionnaire, Berlin questionnaire, and NoSAS score. Indeed, Harvin et al. found that patients with a high risk of sleep apnea, as assessed using the Berlin score, had a higher rate of hypoxemia during conscious sedation for colonoscopy .However, the first two items included a variety of subjective factors, such as snoring, fatigue, and drowsiness. These indicators are easily influenced by the ability to understand, cognition, and education of patients. The NoSAS score is determined by less subjective metrics, such as age, sex, neck circumference, and BMI, with the only subjective item being snoring  . The scaThe MMP is thought to be a simple and quick instrument for assessing airway patency before intubation . PreviouThe advantage of this study is that it represents one of the most recent clinical studies to analyze the applied value of the NoSAS score combined with MMP in diagnosing hypoxemia during routine sedation for gastrointestinal endoscopy. These indicators are relatively objective, concise, and suitable for fast-paced ambulatory surgeries. However, this study is, of course, not without its limitations. First, our study was conducted in only one single center. These results require further validation in polycentric and multiracial populations. The NoSAS questionnaire is based on a European population, and there may be ethnic differences in its screening effectiveness. Second, the patients included in this study only had ASA I-III; these findings may not hold true in ASA IV-V patients who are at a much higher risk of developing hypoxemia and other adverse events. Third, we did not assess the independent predictive effect of MMP on hypoxemia. Although in this study, the evaluation of the MMP was carried out in a unified position and strictly in accordance with the study’s standards, such research results may still not be universally applicable, as this is a single indicator and may lead to different grades due to the different patient positions. Poor inter-examiner agreement may have affected their predictive value. In summary, the NoSAS questionnaire combined with MMP can significantly improve the sensitivity and specificity of hypoxemia, which can be used clinically for hypoxemia screening to facilitate early detection and intervention.As a new screening tool, the NoSAS questionnaire is simple, convenient, and has a certain screening value for hypoxemia, especially with the NoSAS score cutoff of 9. Combined with the modified Mallampati grade (MMP) may be more helpful to the screening of hypoxemia.


Immune checkpoint inhibitors (ICIs) induce impressive antitumor responses but may lead to acute kidney injury (AKI) associated with ICI therapy (AKI-ICI). Biomarkers distinguishing AKI-ICI from AKI because of other causes (AKI-other) are currently lacking. Because ICIs block immunoregulatory pathways, we hypothesized that biomarkers related to immune cell dysregulation, including tumor necrosis factor alpha (TNF-α) and other markers of B and T cell activation in the systemic circulation and kidney tissue, may aid with the diagnosis of AKI-ICI.n = 14) or AKI-other (n = 10). We compared markers of kidney inflammation and injury  as well as plasma and urine levels of T cell-associated cytokines -2, IL-4, IL-6, IL-8, IL-9, and IL-10) between groups. We also compared T-cell responses in the systemic circulation and in kidney tissue across groups, using mass cytometry systems.This is a prospective study consisting of 24 participants who presented with AKI during ICI therapy, adjudicated to either have AKI-ICI . The discriminatory ability of TNF-α on AKI cause was strong , and TNF-α pathway may serve as a potential target for therapeutic intervention.  Patients who had blood, urine, and/or kidney biopsy data available at the time of AKI were included in this study. Blood and urine from kidney donors obtained before kidney donation and time zero implantation kidney biopsies were also collected and used as healthy controls. ICIs were defined as the following: cytotoxic T lymphocyte antigen 4 inhibitors (ipilimumab), programmed cell death protein 1 inhibitors , and programmed cell death ligand 1 antibodies . Patients who did not provide research authorization were excluded. This study was approved by Mayo Clinic Institutional Review Board.Demographic characteristics, kidney function, proteinuria, and medication history at presentation were recorded via manual chart review. Baseline creatinine level was defined as the last stable serum creatinine value before initiating ICI therapy in patients or kidney donation in the control group. AKI events were defined as a ≥1.5-fold increase in serum creatinine level from baseline or an increase of ≥0.3 mg/dl (grade 1 kidney toxicity).Peripheral blood samples were obtained from patients at the time of AKI. All samples were collected at Mayo Clinic’s central laboratory and PBMCs were processed in the research laboratory. PBMCs were isolated using density-gradient centrifugation (Ficoll-Paque solution)  and cells were then slowly frozen to −80 °C and subsequently to less than −196 °C in liquid nitrogen for batch analysis.et al.,et al.Among patients with an AKI event, patient derived PBMCs were isolated from whole blood by Ficoll-Hypaque density-gradient centrifugation and cryopreserved in fetal bovine serum (Thermo Fisher cat# 26140079) with 10% dimethyl sulfoxide (Sigma Aldrich cat# D2650). Stored samples were thawed for acquisition in a single batch to minimize variability. Samples were stained according to a previously established protocol developed at the Mayo Clinic Immune Monitoring Core with an antibody panel focusing on cell surface antigens .17 CustoAll tissue staining and slide preparation was performed by the Mayo Clinic Pathology Research Core. Please see the imaging mass cytometry methods section in the Supplementary materials including Collected blood and urine were transferred to the research laboratory and used to measure cytokines from plasma and urine samples. They were aliquoted and stored at −80 °C and thawed preceding the experiments. Urine and plasma samples were collected at the time of the diagnosis of AKI or within 7 days of the kidney biopsy . We used the manufacturer validated MILLIPLEX MAP Human Cytokine  customized proinflammatory panel to test plasma and urine TNF-α, interferon-gamma, IL-2, IL-4, IL-6, IL-8, IL-9, and IL-10, catalog number # HCYTA-60K. We normalized all the urine cytokines to urine creatinine to account for urine concentration differences using a creatinine parameter assay kit, catalog number #KGE005. The detection ranges of each assay are outlined in Human urine neutrophil gelatinase-associated lipocalin was tested by enzyme-linked immunosorbent assay according to the manufacturer’s protocol . Human urine kidney injury molecule-1 was tested according to the manufacturer’s protocol .We performed immunohistochemistry staining for TNF-α to evaluate expression in the kidney tissue to confirm results of the multiplex assay. Briefly, formalin-fixed paraffin-embedded sections were deparaffinized and rehydrated. Antigen retrieval was performed using Dako Target retrieval  and slides were stained with TNF-α  using Vector Labs Vectastain Elite ABC HRP kit  according to manufacturer’s instructions. These slide images were captured with ZEISS Axio Observer and edited in ZEN software . An image-analysis code in MATLAB  was used to estimate the percentage TNF-α based on the intensity and area of staining . The staining intensity therefore was semiautomatically quantified in 15 to 20 fields and expressed as a percentage of the slide stained. Results from all fields were then averaged per patient.n (%) for categorical variables. Comparisons of measures across AKI groups were evaluated using the equal variance t-test for normally distributed variables, the Wilcoxon rank sum test for non-normally distributed variables, the χ2 test for categorical variables where the expected cell counts were >5, and the Fisher exact test for categorical variables where the expected cell counts were <5. The discrimination between AKI-ICI and AKI on the basis of log-transformed TNF-α levels was evaluated based on area under the curve index estimates derived from a receiver operating characteristic curve fit using logistic regression, with 95% confidence intervals derived using the DeLong method. Correlations were evaluated using Spearman’s rho. Values below the limits of detection were imputed by dividing the minimum detection limit by 2. All analyses were performed using SAS version 9.4  and R version 4.1.2 . All P-values were 2-tailed and were considered statistically significant at the 0.05 α level.Summary statistics were presented as mean (SD) for continuous normally distributed variables, median (interquartile range) for continuous variables with skewed distributions, and as During the study period from April 1, 2021 to April 1, 2022, a total of 28 patients were referred to the Nephrology Division at Mayo Clinic Rochester with suspected AKI associated with ICI therapy. All patients referred were enrolled in the study for blood and urine collection. Among these patients, 4 (14%) had AKIs that were directly attributable to non-ICI causes  or did not meet criteria for sustained AKI and were excluded from further analysis. A total of 24 patients remained that had possible ICI-related AKI. Of these, 14 (58%) patients had clinically suspected or biopsy-proven AKI-ICI, whereas the remaining 10 (42%) had other causes for AKI. Twelve healthy kidney donors from another internal Institutional Review Board approved study were also used as controls see .Figure 1n = 24 patients with AKI are presented in P = 0.019). There were no significant differences observed in overall irAE rates or type of ICI between the 2 groups. In addition, there were no significant differences observed in administration of other cancer therapeutic agents  within 1 month before the AKI diagnosis. Renal recovery tended to occur more frequently in the AKI-ICI group compared to the AKI-other group, but results were not statistically significant.Baseline characteristics for the n = 10, 100%), whereas in the AKI-other group, acute lesions were acute tubular injury in 2 (50%) patients and renal thrombotic microangiopathy in 2 (50%) patients, with mild to moderate interstitial fibrosis or tubular atrophy in all 4 (100%) patients. In the AKI-ICI patient group, 9 (90%) had acute tubular injury and 2 (20%) had manifest tissue eosinophilia. Histologic features of these patients are presented in Kidney biopsy was performed in 10 of the 14 (71%) AKI-ICI patients and 4 of the 10 (40%) patients with AKI-other. Among these, AIN was the predominant acute lesion in the AKI-ICI group  and AKI-other (n = 4), as well as in kidney tissues from the healthy controls (n = 3) (see P = 0.009).We also examined TNF-α expression in kidney tissues from the 2 AKI groups AKI-ICI (= 3) see . SignifiWe characterized immune cell phenotypes in peripheral blood of the patients who developed AKI while on ICI therapy using mass cytometry methods. This high parameter cytometry system allowed us to simultaneously quantify multiple immune cell populations with single-cell resolution. Because certain drugs are expected to have a significant impact on the peripheral blood immune profile, patients using immunosuppressive drugs at the time of AKI were excluded from this analysis. In the subset of patients with available PBMCs and who were not on any immunosuppressive at the time of their AKI event, we found no significant differences in the single cell phenotype by cell assignment, although there were elevated counts of natural killer T cells in the AKI-ICI group compared to those with AKI-other see .Three patients in the AKI-ICI group also had subsequent PBMCs collected following AKI while tapering immunosuppressive therapy for the treatment of interstitial nephritis, as illustrated in P < 0.05 for all), indicating a potential role of these immune cell subsets in AKI-ICI .Similar results were observed when we evaluated the relative abundance of single marker positive cells across the 2 AKI groups see , with siAn alternative, unsupervised method to evaluate differences between patient groups is to use dimensionality reduction to group cells exhibiting similar characteristics together to investigate the relative relationships between individual antibody markers and the patient groups themselves. To accomplish this, we performed uniform manifold approximation and projection (UMAP) projection to reduce 26 antibodies  down to a 2-dimensional projection, in which cells with similar marker characteristics likely corresponding to similar phenotypes cluster together. The UMAP projection shown on et al.,In this pilot study, we have demonstrated that urine TNF-α, IL-2, and IL-10 levels are higher in patients with AKI-ICI compared to those with AKI-other. These findings in conjunction with strong expression of TNF-α in the kidney biopsies suggest that TNF-α originates primarily in the kidneys. Therefore, our results suggest that urinary levels of TNF-α are higher in patients with AKI-ICI with pathology demonstrating AIN, and thus may serve as a useful biomarker to distinguish AKI-ICI from other clinical causes of AKI while on ICI therapy. The results of this study also corroborate the findings of Moledina et al.Another important and novel finding from this study is the kidney tissue immunoprofiling characterization in patients with AKI-ICI. Using imaging mass cytometry, we found an abundance of specific immune cells including CD4 memory, T helper, and dendritic cells in the kidney tissue of patients who developed AKI-ICI. These findings suggest that dendritic cell-T cell interaction within the AKI-ICI and the subsequent T cell activation may contribute to the underlying pathophysiology. Interestingly, a recent study published by Lozano ,,,,,Previous studies have detected both CD4+ and CD8+ T cells in kidney tissue of patients with AKI-ICIet al. showing early T cell clonal expansion at the timing of severe irAEs.In this study, we did not find significant differences in the single cell phenotype by cell assignment of PBMCs; however, natural killer T cells tended to be elevated in the AKI-ICI group compared to those with AKI-other. Furthermore, from the assessment of detailed immunophenotyping of peripheral blood from 3 patients who developed AKI-ICI and were subsequently controlled with corticosteroids, we observed changes in the immune cell response. We also discovered that when further stratifying T cells into CD4+ and CD8+ subsets, most patients had these immune cells decreased with administration of corticosteroids. Notably, for patient #1 we noticed an increase in the proportions of circulating CD8+ T cells and CD4+ T cells after rechallenging, and this was accompanied by concomitant elevations of creatinine. This phenomenon was also identified by Lozano et al.To our knowledge, this is the first study to describe the use of novel biomarkers and immune cells subsets that are important regulators of kidney-associated irAEs leading to AKI-ICI. We have shown that TNF-α is a pivotal cytokine contributing to AKI-ICI; this is an important finding, becuase TNF-α blockade could have steroid-sparing potential in achieving durable and complete renal recovery in patients with refractory AKI-ICI as previously shown by Lin However, our study does have several limitations. Our patient cohort reflects a Midwestern, largely Caucasian population. Therefore, we cannot generalize these findings to other patient populations. Because of our limited sample size, our study did not allow for multivariable adjusted analyses to control for potential confounders. Furthermore, we did not have a control group of ICI- treated patients without AKI, given that kidney biopsies would not be clinically indicated in this population. Larger cohort studies are needed to develop multivariable risk prediction models for incident AKI-ICI. Because this was an exploratory study, results should be considered as preliminary and subject to more rigorous testing and replications in future studies.Taken together, our study suggests that strong TNF-α upregulation in conjunction with an increase of specific immune cell subsets in the kidney tissue are associated with AKI-ICI and may serve as both biomarkers and potential targets for therapeutic intervention for AIN. Furthermore, immune cell profiling during ICI therapy may help to guide management of AKI-ICI. Further multiomics studies on cytokine levels and immune cell profiling in both peripheral blood and kidney tissue in a larger cohort will help to validate the initial findings seen here, as well as provide novel biologic insights into the pathobiological mechanisms of AKI-ICI, with the ultimate goal of improving patient outcomes.NL has stocks in Checkpoint Therapeutics and is on the advisory board of AbbVie, Takeda, and Aduro. TM is an employee of Deciphex Inc. SM has received royalties from Sorrento Pharma. All other authors have no competing interests.


To investigate the prediction of long-term blood pressure control using the intestinal flora of patients with hypertension.A total of 125 patients with primary grade-2 hypertension who attended the cardiovascular department of Hebei Province Hospital of Chinese Medicine between April 2021 and April 2022 were enrolled; these included 65 patients with substandard long-term blood pressure control (the uncontrolled group) and 60 patients with standard long-term blood pressure control (the controlled group). General clinical data and data on morning stools and diet were recorded for all the enrolled patients. The 16 s rDNA sequencing of faecal intestinal flora was also performed to analyse the differences in intestinal flora between the two groups of patients and to investigate the relationship between blood pressure compliance and the presence of flora.Chao1, ACE and Shannon) results and β-diversity analysis results. At the genus level, the number of Streptococcus and Paraprevotella in patients in the uncontrolled group was greater than that of the controlled group, and the level of Akkermansia and Bifidobacterium was lower than that in the controlled group. A logistic regression analysis of the difference factors found differences in ACE, F/B, Streptococcus, Paraprevotella and Akkermansia in the two groups; these differences remained after correcting for age, gender and body mass index. The receiver operating characteristic curves revealed the following: ACE (area under the curve [AUC] = 85.282), Streptococcus (AUC = 82.705), Akkermansia (AUC = 77.333), Paraprevotella (AUC = 66.154) and F/B (AUC = 60.436).The intestinal flora of the two groups of patients differed in terms of the Firmicutes–Bacteroidetes ratio (F/B), α-diversity analysis (Streptococcus and Akkermansia could provide some prediction of late blood pressure compliance or non-compliance in patients with hypertension.There were significant differences in the intestinal flora of the patients in the controlled blood group compared with that of the uncontrolled group. Therefore, the ACE, genus levels of  Hypertension is one of the most important and controllable risk factors for all-cause morbidity and mortality worldwide and is strongly associated with an increased risk of cardiovascular disease . AlthougIt is well-known that hypertension is associated with genetics . HoweverThe abundance and number of intestinal flora vary according to human diseases, such as obesity, type-2 diabetes, non-alcoholic liver disease, malnutrition and hypertension . StudiesMost clinical studies have focused on investigating the relationship between intestinal flora and its related metabolites on the occurrence , developGiven the current situation of the long-term survival of patients being seriously affected by whether blood pressure standards are met or not, this study aimed to analyse the intestinal flora of patients with hypertension with and without standard blood pressure control; the aims were to explore the method of predicting late blood pressure control by the intestinal flora of patients with hypertension and to provide a basis for the achievement of blood pressure standards in patients with diagnosed hypertension.2018 ESC/ESH Guidelines for the Management of Arterial Hypertension , Streptococcus (AUC = 82.705), Akkermansia (AUC = 77.333), Paraprevotella (AUC = 66.154) and F/B (AUC = 60.436) , AUC = 82.05, AkkerAUC = 77.33, ParapStreptococcus  and the genus Paraprevotella  were negatively associated with blood pressure attainment, and ACE  and the genus Akkermansia  were positively associated with blood pressure attainment. The differences persisted after correction for age, sex and BMI. The ROC curves for the genus level of differential bacteria were plotted to assess the predictive value of gut flora on blood pressure attainment, and the results revealed that ACE (AUC = 85.282), Streptococcus (AUC = 82.705) and Akkermansia (AUC = 77.333) had fair predictive specificity and sensitivity.A comparative analysis of the differential indicators between the two groups of patients and a multivariate regression analysis were performed to statistically identify indicators that may affect blood pressure attainment. The results revealed that intestinal flora F/B , the genus Senegalimassilia, Collinsella and Adlercreutzia) were excluded from the genus-level comparison because of their low detection rates. Considering the actual clinical situation and to avoid the duplication of statistics, only the genus-level Bifidobacterium was included in the regression analysis without the phylum-level Actinobacteria; only one genus-level bacteria, Akkermansia, was analysed under the phylum level of Verrucomicrobia; this bacterium was different in the subsequent genus-level comparison, so a regression analysis was performed by genus level, and thus, it was not included. The phylum Bacteria (unclassified) was not included in the statistics, because it did not have any clinical application.The general clinical data of the two groups of patients did not differ significantly in terms of age, BMI, exercise and diet, which may have interfered with the study outcome, but there were differences in yoghurt intake. Some studies have shown that probiotic supplementation can reduce blood pressure in patients with hypertension . HoweverThe F/B is an important indicator of intestinal flora balance: the larger the F/B value, the worse the flora balance and the more serious the flora disorder. Studies showed that the feeding of minocycline to pregnant and lactating rats resulted in an increased intestinal flora–F/B ratio and increased blood pressure in the offspring, accompanied by decreased levels of plasma acetate and butyric acid . In anotFor the comparison of flora diversity, α diversity reflected the diversity, homogeneity and abundance of the distribution of the intestinal flora in the two groups of patients, and as previous studies in humans  and ratsStreptococcus and Paraprevotella were higher in the gut, and Akkermansia and Bifidobacterium were lower in the uncontrolled group compared with the controlled group. An increase in Paraprevotella and a decrease in Akkermansia have been observed in hypertensive rats during the progression from compensated cardiac hypertrophy to heart failure [Bifidobacterium in the intestinal flora of women with pre-eclampsia. Jin et al. [Akkermansia, propionic acid or butyric acid significantly reduced symptoms in rats with pre-eclampsia. Zhang et al. [Streptococcus levels in patients with pulmonary hypertension compared with those of healthy subjects. Liu et al. [Streptococcus associated with inflammation in the intestinal flora of patients with primary aldosteronism compared with the flora of a healthy group. It has also been reported that Paraprevotella is involved in the pathogenesis of hypertension in salt-sensitive rats [During the initial comparison of genus levels, a large number of differential bacteria were found, but from a practical point of view, the bacteria that were not identified at the genus level and those that were too small in number  were excluded. The bacteria that accounted for more than one-third of the blanks in both groups were also excluded. Finally, the four genus-level bacteria with differences were counted for the regression analysis. Comparing the differences in genus levels,  failure . Chang e failure  found a n et al.  discoverg et al.  found hiu et al.  reportedive rats . The resStreptococcus  and Paraprevotella  were negatively associated with blood pressure attainment, while ACE  and Akkermansia  were positively associated with blood pressure; this association persisted after correction for age, sex and BMI. The ROC curves for the predictive value of blood pressure compliance were plotted, with ACE (AUC = 85.282), Streptococcus (AUC = 82.705) and Akkermansia (AUC = 77.333) having the highest predictive values, providing some basis for later blood pressure compliance in patients attending clinics.The regression statistics of the indicators analysed for differences between the groups showed that intestinal flora F/B  and the genera levels of This study has some limitations. First, it was a single-centre cross-sectional study in which most of the participating population were patients living in the local neighbourhood. Therefore, a multicenter study is needed to expand the representativeness of the research. Second, although the sample size of this study was small, our research found a statistically significant correlation between intestinal flora and the anti-hypertensive effect of medication for grade-2 hypertension. Finally, only intestinal flora was analysed in this study, and subsequent analyses of blood and urine specimens from patients are required to reveal the mechanisms by which intestinal flora affects blood pressure. We plan to conduct a large-population multicenter study in the future to improve the credibility and extrapolation of our findings.Streptococcus and Akkermansia could provide some prediction of late blood pressure compliance or non-compliance in patients with hypertension.There were significant differences in the intestinal flora of patients enrolled in the controlled blood pressure group compared with those in the uncontrolled group. The ACE genus levels of


Laparoscopic procedures have been gaining popularity in veterinary medicine. However, there are no studies evaluating the safety of using dexmedetomidine as an adjuvant during laparoscopy in the veterinary literature. High intra-abdominal pressure and dexmedetomidine might have deleterious cardiorespiratory effects; therefore, this study was conducted to evaluate the effects of intra-abdominal pressure and dexmedetomidine on cardiorespiratory variables in healthy dogs. Five healthy beagle dogs were enrolled in the study, which was conducted with a crossover design. Cardiovascular and respiratory variables were monitored at different intra-abdominal pressures through inducing capnopertioneum. After a washout period, the same protocols were applied with dexmedetomidine administration. Our study revealed that no significant cardiorespiratory effects were observed until intra-abdominal pressure reached 20 mmHg, as well as during the administration of dexmedetomidine. These findings have shown that the administration of a dexmedetomidine infusion may be applicable in laparoscopic procedures in healthy dogs.Intra-abdominal pressure (IAP) elevation during capnoperitoneum can cause adverse cardiovascular and respiratory effects. This study aimed to determine if a sequentially increased IAP affects cardiovascular and respiratory variables in anesthetized dogs and evaluate the effects of the constant-rate infusion of dexmedetomidine (Dex) on cardiovascular and respiratory variables with increased IAP. Five dogs were anesthetized and instrumented, and a Veress needle was equipped to adjust the IAP using a carbon dioxide insufflator. Stabilization was conducted for 1 h, and physiological variables were measured at IAPs of 0, 5, 10, 15, and 20 mmHg and after desufflation. After the washout period, the dogs underwent similar procedures along with a constant-rate infusion of dexmedetomidine. The cardiovascular effects of increased IAP up to 20 mmHg were not significant in healthy beagle dogs and those administered with dexmedetomidine. When comparing the control and dexmedetomidine groups, the overall significant effects of dexmedetomidine were noted on heart rate, cardiac output, and systemic vascular resistance during the experiment. Respiratory effects were not observed during abdominal insufflation when compared between different IAPs and between the two groups. Overall, an increased IAP of up to 20 mmHg did not significantly affect cardiovascular and respiratory variables in both the control and dexmedetomidine groups. This study suggests that the administration of a dexmedetomidine infusion is applicable in laparoscopic procedures in healthy dogs. The abdominal cavity is a relatively compliant confined space, which allows a relatively limited capacity to increase the intracavitary volume or reduce extracavitary compliance before a relative increase in intra-abdominal pressure (IAP) occurs . Increas2 have not been thoroughly investigated.Dexmedetomidine (Dex), an alpha-2 adrenergic agonist, is used to provide reliable sedation, analgesia, and chemical restraint in dogs . MoreoveCO is frequently measured during anesthesia or in critical care medicine, allowing for the early detection of hemodynamic instability . In veteRecently, minimally invasive surgeries using endoscopic procedures have been gaining popularity in veterinary medicine . AlthougFive young adult beagles  were included in this study after obtaining approval from the Institutional Animal Care and Use Committee of Kyungpook National University . They were 10–14 months old, with a median body weight of 10  kg. Prior to the study, all dogs underwent physical examinations, blood analyses, and radiography, and they were deemed to be in good health. The body condition score was 5  points on a 9-point scale. The study followed a prospective crossover design with a 7-day washout period between treatments.The dogs underwent an 8 h fasting period, with access to water until they were transferred to the examination room for anesthesia. A 22-gauge catheter was then placed in one of the cephalic veins, and crystalloid fluids  were administered at a rate of 5 mL/kg/h. Before anesthesia, the dogs were premedicated with tramadol  at a dose of 4 mg/kg (intramuscularly (IM)) and cefazoline  at a dose of 20 mg/kg (intravenously (IV)). Preoxygenation involved administering 100% oxygen at a flow rate of 5 L/min for 5 min, followed by anesthetic induction using alfaxalone  at a dose of 2 mg/kg (IV) over 1 min. After endotracheal intubation, each dog was positioned in dorsal recumbency, and anesthesia was maintained using isoflurane  in 100% oxygen through a circle rebreathing system .2, via pulse oximetry), esophageal temperature, and systolic, diastolic, and mean arterial blood pressures . For arterial blood pressure measurement and blood collection for arterial blood gas analysis, we placed an over-the-needle 22-gauge catheter in the dorsal pedal artery. Arterial blood samples were collected and analyzed using a blood gas analyzer  to determine the pH, partial pressure of oxygen in arterial blood (PaO2), partial pressure of carbon dioxide in arterial blood (PaCO2), bicarbonate (HCO3−), and base excess (BE). Dorsal pedal artery catheters were connected to a pressure transducer , positioned at the level of the heart base, and connected to a catheter using a noncompliant tubing system continuously flushed with heparinized saline . Arterial pulse pressure data, analyzed in the transducer, were transmitted from the multiparameter monitor to the LiDCO™ monitor. The LiDCO™ monitor employs the PulseCO method, not the LiDCO system, to continuously calculate stroke volume (SV), CO, and SVR data in real-time. We also measured end-tidal carbon dioxide (ETCO2), the respiratory rate (RR), and the expired fraction of isoflurane (FE’Iso) using a side-stream infrared gas analyzer . Tidal volume (TV) and minute volume (MV) were recorded using a volume monitor . If ETCO2 exceeded 60 mmHg, intermittent positive pressure ventilation (IPPV) was initiated.Each dog was equipped with monitoring instruments to measure physiological variables. We used a multiparameter monitor  to track heart rate , oxygen saturation  to determine the CO and calibrate the LiDCO™ monitor. In the present study, the velocity–time integral method was applied to measure the CO. This method was performed through measuring the velocity of the left ventricular outflow tract in the left apical five-chamber view using pulsed-wave Doppler. Subsequently, the aortic diameter was measured in the right parasternal long-axis view. SV was calculated using the formula π × (aortic diameter/2)2 insufflator , which can adjust the IAP.The ventral region of the abdomen was clipped and aseptically prepared. Subsequently, a skin incision was made 20 mm caudal to the umbilicus. A 14-gauge Veress needle  was inserted in the incision site, and the correct needle placement was checked via the injection of 5 mL normal saline, followed by aspiration. The Veress needle was connected to an automatic CO2, esophageal temperature, SAP, DAP, MAP, EtCO2, RR, TV, MV, pH, PaO2, PaCO2, HCO3−, BE, SV, CO, and SVR. After data collection, the IAP was gradually increased to 5, 10, 15, and 20 mmHg through insufflating CO2. The dogs were allowed to stabilize for 10 min between each of the IAP adjustments. Physiological variables were measured at six time points: T0 (baseline), immediately after the instrumentation period; T1, 10 min after adjusting IAP to 5 mmHg; T2, 10 min after adjusting IAP to 10 mmHg; T3, 10 min after adjusting IAP to 15 mmHg; T4, 10 min after adjusting IAP to 20 mmHg; and T5, 10 min after desufflation. Following desufflation, meloxicam  was administered to all dogs before their recovery from anesthesia. All catheters were removed, and the dogs were returned to their housing facility.The instrumentation period was standardized to 60 min. Subsequently, FE’Iso was maintained at 1.73% (1.3 × MAC) , and theAfter a 1-week washout period, the dogs underwent similar procedures until 10 min before T0, and an IV loading dose of dexmedetomidine (3 µg/kg) was administered followed by an infusion of 3 µg/kg/h of dexmedetomidine. Immediately following the administration, the FE’Iso was decreased to 0.72% based on a previous study  to maintp value of <0.05 was considered statistically significant. Analyses were performed using Statistical Package for the Social Sciences for Windows .The normal distribution of the data was confirmed using the Shapiro–Wilk test before analysis. All values were presented as means and standard deviations. To compare each physiological variable within the two groups, a repeated-measures one-way analysis of variance was performed. Additionally, the Kruskal–Wallis test was performed for nonnormally distributed data. If significant differences were identified, a post hoc analysis was performed using the Bonferroni test. A Wilcoxon signed-rank test or Mann–Whitney U test was performed for each variable between the two groups at each time point. A All five dogs completed the study without any complications. CO measurements using echocardiograms of the five dogs ranged from 1.264 to 1.75  L/min. No significant changes were observed in body temperature (35.1–37.9 °C) and oxygen saturation (94–100%) over time and between treatments.p = 1.000, p = 1.000; MAP, p = 1.000, p = 0.399; SAP, p = 1.000, p = 0.293; and DAP, p = 0.825, p = 0.141; for T3 and T4 compared with T0, respectively). Compared with the control group, overall significant effects of dexmedetomidine were observed on HR, CO, and SVR during the experiment. SAP, MAP, and DAP increased in T0, T1, T2, and T5 with dexmedetomidine treatment, whereas no differences were noted in T3 and T4 between the control and Dex groups. In the Dex group, SV values decreased significantly in T0, T1, and T2.2, RR, TV, MV, pH, PaO2, PaCO2, HCO3−, and BE were observed between different IAPs and between the two groups. In both treatments, PaCO2 was increased following carbon dioxide insufflation compared with that at baseline T0; however, the results were not statistically significant. Moderate-to-severe hypercapnia (EtCO2 > 50 mmHg) was detected in all five dogs. One dog showed an EtCO2 of >60 mmHg in both treatment periods, and IPPV could not resolve the hypercapnia.The effects of intra-abdominal insufflation with carbon dioxide on respiratory and blood gas variables in the control and Dex groups are summarized in Previous studies have shown that intra-abdominal hypertension not only affects cardiorespiratory function but also disrupts regional blood flow and impairs tissue perfusion, potentially leading to organ dysfunction ,4. HowevThe cardiovascular effects of increased IAP result from the cranial displacement of the diaphragm and compression of the caudal vena cava, directly compressing the heart and leading to reduced preload and CO . In the As previously mentioned, both alpha-2 agonists and abdominal insufflation can impact the cardiovascular system. In human medicine, several studies have evaluated the effects of dexmedetomidine on hemodynamic variables in patients undergoing laparoscopic procedures. These studies used dexmedetomidine infusion rates of 0.1 and 0.2 µg/kg/h, respectively, which provided stable hemodynamic conditions during laparoscopic surgery ,10. In oIn this study, we measured CO, SV, and SVR using the LiDCO™ monitor, which calculates CO through pulse contour analysis. Previous studies have assessed the PulseCO method and reported positive results, demonstrating correlations with the PAC-TD method, considered the gold standard ,22,23. W2 > 50 mmHg) throughout the anesthesia period, regardless of different IAPs. While the causes of hypercapnia can be diverse, in this study, it is believed that respiratory suppression due to anesthetics and the elimination of carbon dioxide through the lungs during capnoperitoneum were the main factors leading to hypercapnia, rather than increased IAP [Previous studies have demonstrated that respiratory disturbances associated with elevated IAPs can occur in pediatric human patients as well as animals ,25. Thesased IAP ,27,28. Tased IAP . In conc2 > 50 mmHg) was observed before abdominal insufflation; after IAP insufflation of up to 15–20 mmHg, end-tidal carbon dioxide concentration reached more than 75 mmHg. Despite persistent manual positive pressure ventilation, severe hypercapnia did not resolve. After desufflation, EtCO2 levels decreased to the level before insufflation. However, why this dog exhibited severe hypercapnia remains unclear.In one dog, in the current study, hypercapnia (EtCO2 insufflator has an automatic relief function that automatically releases excess pressure when the pressure exceeds 20 mmHg. Thus, our study could not evaluate the effects of IAPs over 20 mmHg. Third, plasma drug concentrations were not measured; therefore, possible variations in concentration and their influence on circulation cannot be assessed within the present study. Lastly, the body positions of the dogs were not considered in the present study. Laparoscopic procedures are commonly performed in different positions, such as inverse or reverse Trendelenburg positions; as these positions influence cardiovascular variables, further study is needed to evaluate physiological parameters in different positions.The present study had several limitations. First, this study was conducted with a small sample size. To minimize the influence of individual animal effects on physiological variables, the dogs used in this study were of the same breed, similar size, and age, and a crossover design was applied. Second, the COAn increased IAP of up to 20 mmHg did not have any significant cardiovascular and respiratory effects in healthy beagle dogs. Furthermore, the dogs which were administered dexmedetomidine were not affected by abdominal insufflation. Therefore, this study demonstrates that the administration of a dexmedetomidine infusion may be applicable in laparoscopic procedures in healthy dogs. However, further studies are warranted as the present study was conducted in only one body position and had limited IAPs evaluated.


The starting infusion rate of remimazolam was 0.1 mg/kg/min and was increased or decreased by 0.02 mg/kg/min intervals in the following patient according to the success or failure of the previous patient. Success was defined as a loss of responsiveness within two minutes. Patient enrollment continued until six crossover pairs were observed. The ED50 and ED90 were estimated by centered isotonic regression and the pooled adjacent violators algorithm with bootstrapping, respectively. Twenty patients were included in the analysis. The ED50 and ED90 of remimazolam for loss of responsiveness within two minutes were 0.07 mg/kg/min  and 0.10 mg/kg/min , respectively. Vital signs were stable with an infusion rate of 0.10 mg/kg/min, and no patients required inotrope/vasopressor. Intravenous infusion of remimazolam at a rate of 0.10 mg/kg/min can be an effective approach to inducing general anesthesia in adult patients.Remimazolam is a recently developed anesthetic agent for general anesthesia and sedation. Currently, the optimal infusion rate for the induction of general anesthesia within two minutes remains unclear. We estimated the 50% and 90% effective doses (ED An ideal induction agent is characterized by a fast onset, rapid recovery, and few adverse effects, such as circulatory depression ,2. RemimCompared to propofol, remimazolam presented a more stable hemodynamic profile during and after the induction of anesthesia in previous studies. Patients who were induced by remimazolam showed a significantly lower incidence of hypotensive adverse events ,10, and The manufacturer recommends intravenous administration of remimazolam at a rate of 0.1 mg/kg/min or 0.2 mg/kg/min, and adjustment of infusion rates according to the patient’s conditions for induction of general anesthesia. However, these infusion rates were determined to be doses that showed non-inferiority in terms of safety and efficacy compared to propofol , but notSince remimazolam has been approved only for continuous infusion, we focused on exploring the optimal infusion rate of remimazolam. We hypothesized that there would be a specific optimal infusion rate of remimazolam to induce loss of responsiveness within 2 min in adult patients while maintaining stable hemodynamics in inhalation anesthesia. We investigated the 50% and 90% effective doses of remimazolam using centered isotonic regression and the pooled adjacent violators algorithm (PAVA) with bootstrapping.This prospective dose-finding study was conducted at a tertiary hospital in South Korea between 14 January 2022 and 20 January 2022. Ethical approval for this study (SMC 2021-07-121-001) was provided by the Institutional Review Board of Samsung Medical Centre, Seoul, South Korea, on August 30, 2021. This study was registered at the Clinical Research Information Service before patient enrollment . Written informed consent was obtained from all participants. This study adhered to the ethical principles of the 1964 Declaration of Helsinki and its amendments. This manuscript adhered to the Transparent Reporting of Evaluations with Nonrandomized Designs (TREND) guidelines . All metAdult patients aged 20 to 65 years and with American Society of Anesthesiologists physical status I to II who were scheduled for elective surgery under general anesthesia with inhalation agents were assessed for eligibility. Exclusion criteria included major contraindications of remimazolam, as follows: known allergy or contraindication to benzodiazepine, severe liver disease, heavy alcohol consumption, neuromuscular disease, psychiatric disorders, metabolic disorders, acute narrow-angle glaucoma, and lactose intolerance. Patients who had severe sleep apnea disorder, who showed unstable vital signs before surgery, or who refused to participate were also excluded. According to the intention-to-treat principle, all participants assigned their infusion rate of remimazolam for the dose titration study were included in the analysis.TM, Medtronic, MN, USA) was used to assess the depth of anesthesia. Before induction of anesthesia, each patient performed spontaneous breathing with 100% oxygen for preoxygenation. After more than 2 min of preoxygenation with a fraction of inspired oxygen of 1.0, an intravenous infusion of remimazolam was started at a rate that was allocated to each patient according to the study protocol.The patients did not receive any premedication. After the patients were transferred to the operating room, standard monitors were applied to monitor vital signs, pulse oximetry, electrocardiography, and non-invasive blood pressure. In addition, a bispectral index (BIS) monitor . The infusion rate in each patient was determined based on Dixon and Mood’s up-and-down sequential method . The firA designated study staff member (anesthesiologist), who was blinded to the dose of remimazolam, checked the patient for loss of responsiveness for 2 min from the start of remimazolam infusion. No other anesthetic agents, opioids, or neuromuscular blocking agents were administered during this period. However, if the patient’s blood pressure decreased by more than 20% from the baseline during remimazolam infusion, 5 mg of ephedrine was administered. If a heart rate of < 45 beats/min was observed, atropine (0.5 mg) was administered. Time to loss of consciousness was recorded for 2 min from the start of remimazolam infusion. The blood pressure, heart rates, oxygen saturation, and BIS of all patients were recorded prior to remimazolam administration, at the time of loss of responsiveness, and every minute until 5 min after intubation. The number of inotropes/vasopressors given during remimazolam infusion was recorded.Loss of responsiveness was assessed from the start of remimazolam infusion as follows: The patient was asked to count from 1 to 100 from the start of remimazolam infusion. When the patient stopped counting, the study staff slightly shook the patient’s shoulders and asked them to open their eyes. Loss of responsiveness was defined as no response to gentle touch and verbal command. Success was defined as loss of responsiveness within 2 min from the beginning of remimazolam infusion based on the manufacturer’s recommendations. It was considered a failure if the patient did not lose responsiveness for 2 min. In failure cases, 1 mg/kg of intravenous propofol was administered to induce a loss of responsiveness. Failure cases were included for the determination of the 50% and 90% effective doses (centered isotonic regression and PAVA with bootstrapping) and analysis of hemodynamic variables but excluded from calculating the time required for loss of responsiveness.After the patients were confirmed as having loss of responsiveness (when the dose titration study ended), remimazolam infusion was discontinued until intubation while sevoflurane was administered. The attending anesthesiologist fitted the bag valve mask on the patients and performed manual ventilation with 5 vol% of sevoflurane in a 3:1 mixture of oxygen and air. After confirming proper ventilation without any difficulties, intravenous rocuronium (0.6 mg/kg) and fentanyl (25 µg) were administered to all patients. After more than 2 min, endotracheal intubation was performed carefully. Volatile anesthesia using sevoflurane was maintained to achieve a BIS value of 40–60. During the induction and maintenance of anesthesia, if the blood pressure decreased by 20% from the baseline, intravenous ephedrine (5 mg) was administered. If the heart rate decreased to less than 45 beats/min, intravenous atropine (0.5 mg) was administered.For postoperative analgesia, intravenous hydromorphone (0.01 mg/kg) and paracetamol (1 g) were administered 10 min before the end of surgery. Neuromuscular blockade was reversed with intravenous sugammadex (2–4 mg/kg) based on the number of train of four. Extubation was performed when the patient recovered adequate muscle strength, and all patients were transferred to the post-anesthesia care unit. Before discharge from the post-anesthesia care unit, the study nurse who was blinded to the allocated infusion rate and success/failure of the study assessed intraoperative awareness using a modified Brice questionnaire .Remimazolam was prepared at the same concentration in all cases. Before the patient and anesthesiologist arrived in the operating room, the corresponding author set the infusion pump for each patient according to the infusion rate determined by the up-and-down method. Additionally, the infusion pump was then covered to maintain blindness. Therefore, the infusion rate of remimazolam in each patient was blinded to the patient, the designated study staff who assessed and determined the loss of responsiveness, and the study nurse who evaluated intraoperative awareness in the post-anesthesia care unit. After induction of anesthesia, the covered infusion pump was retrieved and the total amount of remimazolam administration was identified by the corresponding author.The primary endpoint was the 50% effective dose and 90% effective dose of remimazolam infusion rate, which was required for loss of responsiveness within 2 min from the start of infusion in adult patients. The secondary endpoints included mean blood pressure, heart rate, and the BIS value at various time points . Other secondary outcomes included the time interval between the start of remimazolam infusion and the loss of responsiveness, the total infused volume of remimazolam in success cases, the number of patients that experienced hypotension (mean blood pressure) < 65 mmHg, hypertension (mean blood pressure > 140 mmHg), bradycardia (heart rate < 45 beats/min), intraoperative awareness, which was investigated using a modified Brice questionnaire, and the number of patients who required an inotrope or vasopressor during the induction of anesthesia.The 50% effective dose and corresponding 90% confidence interval (CI) of remimazolam for inducing loss of responsiveness within 2 min were calculated using Dixon and Mood’s up-and-down method with a centered isotonic regression ,15. A prThe 90% effective dose and corresponding 90% CI were calculated using a centered PAVA with bootstrapping ,16. Unlep-values < 0.05 were considered statistically significant. Statistical analyses were performed using SPSS version 22  and R statistical software version 3.3.2 . Categorical variables are summarized as numbers (%). The secondary outcomes were evaluated using a Mann–Whitney U test for continuous variables. Repeated measures analysis of variance (ANOVA) was performed to compare the change in hemodynamic variables and the BIS value between the groups. Two-sided Twenty-three patients were assessed for eligibility, but three patients declined to participate. When twenty consecutive patients were enrolled in this trial, six crossover pairs were observed. Therefore, enrollment was stopped according to the study protocol and all twenty patients were included in the estimation of 50% and 90% effective doses that induced loss of responsiveness within 2 min. No patients were excluded from the study. The demographic characteristics of the participants are presented in Assessment of success or failure of loss of responsiveness for consecutive patients is shown in the up-and-down sequence of A total of 11/20 patients successfully showed a loss of responsiveness via remimazolam infusion at rates assigned to each of them. Among the patients who successfully lost responsiveness, the median [interquartile range] total infused dose of remimazolam need to reach loss of responsiveness was 13 ,11,12,13n = 11) and failure group (n = 9) are also presented in Secondary outcomes including hemodynamic change, BIS value, and other study data between the success group  and 0.10 mg/kg/min , respectively. During remimazolam induction, blood pressure and heart rates were maintained within 20% of the baseline values and no patients required vasoactive medications.Remimazolam is a recently approved ultra-short-acting intravenous benzodiazepine for general anesthesia or procedural sedation . DespiteMost previous studies administered remimazolam in combination with remifentanil for the induction of anesthesia. When remimazolam is combined with remifentanil, the recommended infusion rates for anesthesia induction may not be the same as the recommended infusion rate of remimazolam alone. In this study, we estimated the 90% effective infusion rate to be 0.1 mg/kg/min. This result means that the previously recommended infusion rate of remimazolam is relatively high, or that the effect of remifentanil on the loss of responsiveness is not significant when remimazolam is used for induction of anesthesia.This study also evaluated the hemodynamic stability after remimazolam induction. Hypotension frequently occurs during and after anesthetic induction and can threaten patient safety . For thiGenerally, a bolus injection of hypnotics is more practical and preferred during the induction of anesthesia. Indeed, although bolus administration of remimazolam has not been approved, several published trials have explored bolus dosing of remimazolam for induction of general anesthesia. In these trials, the average time from the start of remimazolam injection to loss of responsiveness was 100 s , with doIn this study, we defined the loss of responsiveness as no response to mild shaking of the patient’s shoulder. This definition corresponds to the Modified Observer’s Assessment of Alertness/Sedation (MOAA/S) scale score 1. The MOAA/S scale is frequently used to describe the depth of sedation and anesthesia . HoweverThe present study has some limitations. First, this study included relatively healthy patients with an American Society of Anesthesiologists physical status of I and II. The lack of diversity in the population can limit the generalizability of our findings. The response to remimazolam can vary depending on the patient’s underlying condition. Therefore, further studies are warranted in elderly patients or in patients with compromised circulatory function with an American Society of Anesthesiologists physical status III or higher to confirm the safety and efficacy of remimazolam in such patients. Second, we used a classical up-and-down design with centered isotonic regression and PAVA with bootstrapping with a relatively small sample size. Although it is reasonable to estimate a 50% effective dose and our results are consistent with those of previous studies, a fixed-staircase or biased-coin up-and-down design including more samples could be appropriate to estimate a highly effective dose, such as a 95% effective dose . Third, In conclusion, continuous infusion of remimazolam at a rate of 0.10 mg/kg/min can be an effective approach to induce general anesthesia in adult patients within 2 min (median of 95 s) without untoward hemodynamic side effects.


Pesticides can trigger kidney disease.To describe the exposure to pesticides of patients with chronic kidneydisease on dialysis.Quantitative and descriptive field research, with 90 patients with chronickidney disease on dialysis in two hemodialysis units in the state of SantaCatarina, through the application of a structured questionnaire.Participants were divided into two groups: with and without exposure topesticides. The questionnaire was applied in hemodialysis clinics duringtreatment. Laboratory test values were collected from clinical records. Datawere analyzed using descriptive statistics and association using thechi-square test. For laboratory test data, a comparison of means wasperformed using the unpaired Student’s t-test between the groups.The mean age of exposed participants was 58 years  and that of non-exposed participants was 64 years old . Of the 90 patients, 30% were exposed topesticides. The mean exposure time was 6.7 ± 3.8 hours/day. There was astatistically significant association between the preparation of the mixturewith pesticides and diabetes (p ≤ 0.048). There was no statisticallysignificant difference between the results of laboratory tests in theexposed and non-exposed groups.This study shows that pesticides can be triggering factors for chronic kidneydisease (CKD); however, we must expand research in this field to prove therelationship between exposure to pesticides and CKD. The main factors causing a drop in glomerular filtration rate are chronicdiseases such as diabetes and hypertension; in addition, several chemicals alsocalled xenobiotics can lead to kidney dysfunction.Chronic kidney disease (CKD) consists of kidney damage with progressive andirreversible loss of kidney function. It is estimated that CKD affects more than 10% of the world’s adult population. In Brazil, the prevalence of patients on a chronic dialysis program has morethan doubled in the last eight years. In the state of Santa Catarina, 2,541 cases of chronic kidney disease wererecorded in 2016, according to data from the State Department of Health (2018).CKD is an important medical and public health problem in both developed anddeveloping countries. In Santa Catarina, there is also intense use of pesticides, but the use isdirected to apple cultivation mainly, in which an average of 35 applications percrop can occur.Brazil is a leading country in agricultural production, and also the world’s largestconsumer of pesticides. There are regions in the country where the use of pesticidesis more intense due to the types of crops and size of the cultivated area;therefore, the exposure and the risk of intoxication are higher. For example, inMato Grosso, Goiás and Mato Grosso do Sul there is extensive production of soy,which is currently the crop that most consumes pesticides in Brazil; despite this, agricultural production in the region is based on conventionalcultivation with the use of pesticides for the management of agricultural crops. Theexpressive and frequent use of pesticides causes damages with environmental andhuman contamination. In relation to human health, the harmful effects of the use of pesticidesare diverse and can cause acute or chronic poisoning. In Santa Catarina, the 2018 National Health Surveillance Report forPopulations Exposed to Pesticides showed that, in 2015, there were 695 notified cases. Studies also point to cases of acute poisoning in the Serra region of Santa Catarina. Research has shown that several chemical groups of pesticides can developthe main risk factors that cause chronic kidney disease or directly affect the kidneys. In general, pesticides can trigger CKD directly and indirectly, or eventhrough the effect of heat stress on farmers due to the ergonomics of PersonalProtective Equipment (PPE) combined with insufficient fluid intake, which leads tobody water depletion and consequent harm to kidney health.Santa Catarina’s agriculture is developed with high technological levels, applied inintensive production systems and with high added valueConsidering that the use of pesticides in Brazil has been growing at an alarming ratein the last decade, and the number of chronic kidney patients is growing at the sametime, the objective of this study was to describe the exposure to pesticides ofpatients with chronic kidney disease on dialysis.This was a quantitative and descriptive study, that took place in two kidney therapyclinics in the state of Santa Catarina: hemodialysis clinic Centro de Terapia Renalde Lages, SC, and Clínica de Hemodiálise de Videira, SC.All the participants in the study were patients with stage-5 CKD undergoing dialysisduring the study period (July 2020 to March 2021), who met the inclusion criteria:undergoing dialysis treatment (stage 5) in the clinics in the cities of Lages andVideira, they were 18 years of age or older and agreed to participate in the studyof their own free will, signing the Free and Informed Consent Form (FICT). Patientswho did not accept to participate in the study and those who did not have thephysical and/or psychological conditions to be part of the study – evaluated by thenephrologist – were taken off.Sixty-three patients were investigated at the clinic in Lages and 27 patients at theclinic in Videira, totaling 90 patients, and the technique used to choose theparticipants was intentional.Data collection was performed through the application of a questionnaire, analysis ofmedical records and collection of blood-test results from patients.The questionnaire, prepared by the team of researchers and divided into two stages,consisted of closed and some open questions. The first step was answered by all thestudy participants. The first part consisted of: identification of somesociodemographic data; investigation of the participants’ lifestyle, such as diet,physical activity, dependence on alcoholism and smoking, water consumption andrelationships; and gathering information on the etiological factors that can lead tothe development of CKD, with questions about possible exposure to pesticides, otherxenobiotics that are not pesticides and the presence of comorbidities. Suchcategorization made it possible to divide the study participants into two groups:without exposure to pesticides (control group) and with exposure to pesticides. Forthe exposed group, only exposure to pesticides was considered and not to otherxenobiotics.The second stage of the questionnaire was answered only by participants who claimedto have been exposed to pesticides at some point in their lives. The researchparticipant’s association with agriculture and possible lifetime exposure topesticides was explored. For this, questions were elaborated that addressed: timeand place of work with agriculture, use of pesticides, types of pesticides used, wayof handling pesticides, use of personal protective equipment (PPE), exposure topesticides, among other information.The questionnaire was administered to the patients by the researchers at the dialysiscare centers during the hemodialysis session. The questionnaire was read by theresearcher and answered by the interviewee, and the researchers recorded the answersgiven by the interviewees. The application of the questionnaire lasted an average of30 minutes.The clinical records of the CKD patients were also analyzed, in which the results oftests that are already part of the clinical evaluation were collected, such aslevels of urea, creatinine, transaminase, potassium, calcium and phosphorus.The study started after approval by the Research Ethics Committee, approved accordingto protocol number 4,073,680. Before starting the study with the participants, theinformed consent was read to those in the study and only continued with thoseparticipants who agreed with the study and signed the document.Data were analyzed using descriptive statistics with frequency, mean and standarddeviation of the mean. For categorical data, a variable association test wasperformed using the chi-square test. For numerical data, the Shapiro-Wilk normalitytest was initially performed; with confirmed normality, the means of the controlgroup (without exposure to pesticides) and those of the group with exposure topesticides were compared using the unpaired Student’s t-test. The significance leveladopted was p < 0.05. Data were processed and analyzed using the SPSS 2.0statistical program.The mean age of the exposed participants in this study is 58 years  and that of the unexposed, 64 years . Most participants were male, both exposed and not exposed to pesticides(66.7%), married (29.6% of the exposed group and 61.9% of the non-exposed group) andhave completed elementary school (48.1% of those exposed and 53.9% of those notexposed).Regarding the lifestyle of the patients, most of them did not perform physicalexercises, both the participants in the group exposed to pesticides (77.8%) and theparticipants in the group of those not exposed (85.7%). Most did not have anyleisure activity . Of thosMost of the participants in both groups reported taking continuous use medication; and in bothgroups the majority did not smoke  .As for eating habits, the majority reported low salt intake in both groups , consumption of fatty foods and sweets  up to three times a week and consumption ofalcoholic beverages only once a week  . InaddiAs for relationships, the majority of both groups reported good family life , with neighbors , with the doctor  and with society in general . .Regarding comorbidities in the exposed group, most patients did not have diabetes(81.5%), and all of them underwent some type of treatment; in the non-exposed group,most had diabetes (60.3%), and most of those who had the disease were under sometreatment (50.8%) .The mosAs for the risk factors associated with chronic kidney disease, of the 90 patients,27 (30%) had been exposed to pesticides, and 23 (25.6%) had been exposed to sometype of xenobiotic , such asOf the 27 patients who had already been exposed to pesticides, three of them (11.1%)were still working in agriculture, and those who stopped working did so for anaverage of 11.4 years . When theexposed were asked about the categories of agricultural crops they worked or hadworked with, the responses were grains (19.2%), fruits (38.5%), vegetables, tobacco and more than one category (34.6%). The maintypes of pesticides to which the participants were exposed to are shown in It is noteworthy that, currently, the majority no longer use pesticides (81.5%), and on The mean exposure time reported by exposed patients was 6.7 hours daily . Few (7.4%) still prepared pesticide syrup and33.3% had already prepared it at some point in their lives . Among tFew also currently used pesticides (11.1%). However, another 44.4% had alreadyapplied at some point in their lives, on average for 11.1 years . Most patients (66.7%) reported that the distance betweenthe pesticide storage place and their residence is/was greater than 30 meters;however, 33.3% reported that it is/was less than this distance. As for thepreparation of pesticides, the majority (55.6%) reported that it is/was done in ashed exclusively for this purpose, although there are still irregularities . For theThe highest percentage (59.3%) of exposed participants stated that they did not wearpersonal protective equipment (PPE) . Of thosAs for the washing of PPE, the highest percentage of those who use/used (33.3%)reported that the individual washes the PPE himself and generally washes it everytime he uses/used it or weekly. Finally, most patients did not eat (85.2%) or smoke(66.7%) when handling pesticides .There was a statistically significant association between the preparation of themixture with pesticides and the presence of diabetes; that is, patients who reportedthat they had already prepared the pesticide syrup at some point in their lives alsoreported having diabetes (p ≤ 0.048). There was also a statistically significantassociation between the use of a tractor with a protective cabin and medication forcontinuous use, and patients who reported that they used a tractor for sprayingpesticides without a protection cabin also reported that they currently usedmedication continuously (p ≤ 0.009). There was a significant association between thetreatment given to clothes worn under PPE and the presence of hypertension; that is,patients who reported that they separated clothes contaminated with pesticides fromother clothes when washing at home also reported that they did not have hypertension(p ≥ 0.046).The results of laboratory tests  did not indicate changes, according to reference values for thesepatients. There was no statistical difference when comparing the results oflaboratory tests of dialysis patients not exposed and those exposed to pesticides,as shown in .In general, it was evidenced in this research that 30% of the studied sample isexposed or was exposed to pesticides throughout their lives, as well as somestatistical associations were found between exposure to pesticides with the presenceof diabetes, hypertension and continuous use of medication. Research around theworld indicates that pesticides can be considered precursor agents of chronic kidney disease.Regarding the characterization of the studied sample, there is a predominance ofchronic kidney disease (CKD) in males, in the approximate age group of 60 years.Increasing age can cause renal atrophy and reduction of the renal cortex from theage of 30 onwards. Thus, aging can cause several changes in the renal system, suchas atrophy, fibrosis, glomerular sclerosis, among others. Having completed higher education is a protective factor for CKD, asindividuals with more favorable socioeconomic conditions, such as higher education,are less exposed to risk factors for the disease. In addition, these individualsusually have health insurance, and therefore greater access to tests and earlier diagnoses.Most research participants, from both groups, had only elementary education, whichcorroborates another study on the profile of dialysis patients demonstrated the correlation between smoking as a risk factor for CKDprogression. Inhalation of tobacco smoke produces several gases, some withnephrotoxic potential, such as heavy metals, which cause tubular toxicity, such ascadmium and lead.Regarding lifestyle, research has shown that smoking is an important risk factor fortriggering CKD. Elihimas Jr. et al..The prevalence of sedentary habits and the intake of foods rich in fats and sugars upto three times a week stand out as unfavorable practices. The lack of a physicalexercise routine, and other habits, is directly related as a risk factor toCKD-based comorbidities, such as arterial hypertension and type 2 diabetes mellitus. According to the Brazilian Census of Nephrology (2020), arterialhypertension is the main etiology of CKD. These comorbidities require periodic monitoring and appropriate treatment;otherwise, they will contribute to a deleterious prognosis for patients with chronickidney disease.In the presented sample, the highest percentage of dialysis patients had arterialhypertension, being the most prevalent pathology, and type 2 diabetes mellitus. InBrazil, about 63% of CKD cases are from patients with both comorbidities.A large part of the sample used medication for continuous use, primarily to controlarterial hypertension. The damage caused by hypertension in chronic renal patientscan be, among others: renal vasoconstriction – mainly of the preglomerularvasculature, microvascular damage, loss of peritubular capillaries, local ischemia,inability to excrete salt and hypertensive renal disease.Despite the most eminent causes of CKD, especially in developed countries, thedescribed pathology is also related to occupational and environmental causes,including exposure to pesticides and other xenobiotics among the hypotheses, sincecertain pesticides commonly used in many parts in the world are recognized by thehuman body as nephrotoxic substances. As shown by some studies in the mountainous region of Santa Catarina, whereagriculture is one of the main economic drivers, there are deficiencies in the useand handling of these chemicals, as well as cases of acute intoxication and evenassociations with diseases. An international study indicated an association between CKD and chronicexposure to specific pesticides.Research in Brazil has shown cases of farmer intoxication by pesticides related tothe occurrence of chronic diseases. Usually, such repercussion is conditioned to factors related to improperhandling of substances, the high toxicity of certain products and the non-use orincorrect use of PPE.Most kidney patients in our study had been exposed to pesticides. Pesticides canaffect kidney tissue from tubular cell toxicity or cause changes in renal bloodflow, which leads to secondary tubular damage at a molecular level. In addition, inpatients exposed to pesticides, the presence of large dysmorphic lysosomes in theproximal tubular cells of the nephrons was detected – very similar to what occurs inpatients treated with calcineurin inhibitors after kidney transplantation. It is understood that PPE still do not have ergonomic conditions, asresearch has shown that farmers who do not wear PPE report that they did not use itprecisely because of the discomfort, difficulty breathing and heat caused by suchequipment, among other arguments, since PPE are not equipment designed for use by farmers but adapted from PPEfor industrial use.In this study, many did not have PPE, in addition, part of the respondents of theexposed group remained with PPE underwear wet with pesticides throughout the workperiod. PPE, despite not being 100% efficient in protecting against the toxiceffects of pesticides, are essential to minimize the risk of acute and/or chronic poisoning. Dehydration, heat stress and heat overload may be factors associated withagricultural work that could be related to CKD.Among the factors that make pesticides possible triggers of CKD is the effect of heatstress due to the ergonomics of the PPE, combined with insufficient fluid intake byfarmers during work or throughout life, as it can lead to body water depletion and,consequently, harm to kidney health.In the present study, most patients exposed to pesticides had already prepared themixture and sprayed pesticides at some time in their lives and applied the productsby means of tractors without a protective cabin, which can further increase the riskof exposure, since the worker is more exposed to pesticide droplets that dissipateinto the atmosphere after spraying.Although some countries regulate the need to use tractor cabins, as well as the typeand way of using these cabins to protect themselves from contact with pesticides, inBrazil most tractors used in pesticide applications still do not have protectioncabins, leaving the operators only to use the PPE as a way to avoid possiblecontamination by the substances.Among the categories most susceptible to the toxic effects of pesticides,agricultural workers and pesticide applicators are the most susceptible. In thepresent study, the average time of exposure to pesticides reported by patients was6.7 hours. Based on these determinants, mainly on the chronological and physicalcomponent, on body water depletion, it is stated that daily work for more than 6hours in the field under the sun is also an important modulator of nephrotoxicity. In the scientific community, there is convincing evidence that exposure toglyphosate is a significant factor in CKD associated with the use of pesticides. Thus, there is a likelihood with the chemical products used by exposedpatients, evidencing that this herbicide may be a risk factor associated with kidneypatients in this study.In our study, of the six main active ingredients used by patients, two of them,glyphosate and mancozeb, are correlated with the most widespread toxic substancesthroughout the national territory, emphasizing the concern with the indiscriminateuse of these substances and their consequences.There was also statistical evidence of the association between the preparation of themixture with pesticides and diabetes, since patients who have already prepared themixture with pesticides at some time in their lives are also carriers of diabetes.In Brazil, some authorized pesticides are associated with endocrine disruption,including the mancozeb, which exposure was reported by the study-patients as one ofthe pesticides to which they were exposed. In Brazil, populations exposed to theseagricultural products tend to be more vulnerable to the onset of diseases related tothe immune and endocrine systems, including diabetes. Nephrotoxic substances, such as heavy metals, paints and others, can causevarious types of kidney damage with serious consequences, since the kidneys are themain route of organic excretion of such substances. In this study, the intention was not to deepen the investigation of otherxenobiotics, because the study was focused on pesticides only.It is also noteworthy that patients in this sample were exposed to some other type ofxenobiotics, in addition to pesticides, which is also a factor that may havecontributed to the onset of CKD. In the present study, many patients reportedexposure to heavy metals. Research has shown that these xenobiotics have thepotential to cause kidney damage. Thus, from dialysis, excess fluid and toxins are removed from the blood ofchronic kidney patients with the subsequent return of clean blood to the patient.The lack of laboratory alterations in the study patients and the absence ofdifferences in these exams of patients exposed to and not exposed to pesticides werealready expected, since all of them undergo hemodialysis. During the process ofdialysis, blood filtration occurs, that is, hemodialysis promotes the elimination ofwaste harmful to health, such as excess salt and fluids, as well as helps the bodymaintain the balance of substances such as potassium, urea and creatinine, among others. This fact constitutes a probable argument for the lack of statisticaldifference between the laboratory tests of exposed and non-exposed patients in thepresent study.Thus, patients exposed to pesticides may, from the dialysis process, have eliminatedpossible residues and toxins that may have remained in the body during exposure.Research has shown that the procedures currently used in nephrology may soon also beused more widely for the detoxification process of patients poisoned by pesticidesIn general, this study contributes to the technical, scientific and social fields inorder to expand the dissemination of the risk to human health associated with theuse and handling of pesticides. We also suggest this study should be expanded withhumans and/or animals, mainly of an experimental nature, which can prove therelationship between exposure to pesticides and CKD, as well as the importance ofother risk factors in the development of the disease.