12010523
What are high-flow and low-flow oxygen delivery systems?
To the Editor:

We read with interest the article, “A Pilot Study of Normobaric Oxygen Therapy in Acute Ischemic Stroke.”1 However, we have certain reservations with the terminology and the method of oxygen delivery used by the authors.

First, regarding the terminology of “high-flow” oxygen used by the authors, the authors mention the flow rates but not the oxygen delivery system used. An oxygen delivery system is a device used to administer, regulate, and supplement oxygen to a subject to increase the arterial oxygenation. In general, the system entrains oxygen and air to prepare a fixed concentration required for administration. Oxygen delivery systems are generally classified as low-flow or variable-performance devices and high-flow or fixed-performance devices.2 Low-flow systems provide oxygen at …
39024721
Efficacy and safety of iodopovidone in chemical pleurodesis: a meta-analysis of observational studies.
The search for an 'ideal' agent for pleurodesis continues. Iodopovidone is a topical antiseptic and has been shown to be safe and effective in many studies. The aim of this study was to evaluate the efficacy and safety of iodopovidone as an agent for chemical pleurodesis. We performed a systematic review of all the observational trials which have used iodopovidone for chemical pleurodesis. Six studies including 265 patients who had undergone chemical pleurodesis with iodopovidone were included for this analysis. Iodopovidone was used for variety of indications, which included pleural effusion (157 patients), and pneumothorax (108 patients). Pleurodesis was performed through tube thoracostomy in 144 patients and through thoracoscopy in 121 patients. The success rate of pleurodesis varied from 64.2% to 100%, and summary success rate of all the studies was 90.6% (95% confidence intervals [CI], 86.4-93.8). The success rate was independent for the procedure (tube thoracostomy [126/144; 87.5%, 95% CI 80.9-92.4] or thoracoscopy [114/121; 94.2%, 95% CI 88.4-97.6]) used for performing pleurodesis or for the indication (pleural effusion [139/157; 88.5%, 95% CI 82.5-93.1] or pneumothorax [101/108; 93.5%, 95% CI 87.1-97.4]). The only significant complication reported was chest pain of varying degree. Systemic hypotension was reported in three patients in only one study. There were no deaths related to chemical pleurodesis with iodopovidone. Overall, this review supports the safety and efficacy of iodopovidone as an agent for chemical pleurodesis in cases of recurrent pleural effusions and pneumothoraces regardless of their etiology.
33491888
Noninvasive ventilation in ARDS caused by Mycobacterium tuberculosis: report of three cases and review of literature
26068481
Efficacy and safety of iodopovidone pleurodesis through tube thoracostomy.
OBJECTIVE
To evaluate the efficacy and safety of iodopovidone as an agent for pleurodesis through tube thoracostomy in patients with recurrent pleural effusions and pneumothorax.


METHODS
This was a prospective study in which pleurodesis was performed with a solution of 20 mL 10% iodopovidone and 80 mL normal saline solution infused through a tube thoracostomy and left in the pleural cavity for 4 h.


RESULTS
A total of 64 patients (34 men) with a mean (+/-SD) age of 47.1 +/- 15.4 years were included. There were 37 cases of pleural effusion and 27 of pneumothorax. A complete response (neither reaccumulation of fluid nor recurrence of pneumothorax) was obtained in 32 (86.5%) patients with pleural effusion and 25 (92.6%) patients with pneumothorax. A second procedure (i.e. repeated pleurodesis) was attempted successfully in four patients in the pleural effusion group. All patients experienced chest pain to a varying degree as recorded on a Visual Analogue Scale (median 50.5, range 10-95). Seven patients developed fever and one immunocompromised patient developed empyema following the procedure. There were no recurrences at a median follow up of 5 months (range 3-15 months) in the pleural effusion group, and 13 months (range 6-24 months) in the pneumothorax group.


CONCLUSIONS
Iodopovidone can be used as an effective and safe agent for (chemical) pleurodesis (through tube thoracostomy), which is inexpensive and readily available.
45999589
Noninvasive ventilation in acute heart failure.
3038618
Is the mortality higher in the pulmonary vs the extrapulmonary ARDS? A meta analysis.
BACKGROUND AND AIM
ARDS can occur from the following two pathogenetic pathways: a direct pulmonary injury (ARDSp); and an indirect injury (ARDSexp). The predisposing clinical factor can influence the pathogenesis and clinical outcome of ARDS. This metaanalysis was aimed at evaluating whether there is any difference in mortality between the two groups.


METHODS
We searched the MEDLINE, EMBASE, and CINAHL databases for relevant studies published from 1987 to 2007, and included studies that have reported mortality in the two groups of ARDS. We calculated the odds ratio (OR) and 95% confidence interval (CI) to assess mortality in patients with ARDSp vs patients with ARDSexp and pooled the results using three different statistical models.


RESULTS
Our search yielded 34 studies. In all, the studies involved 4,311 patients with 2,330 patients in the ARDSp group and 1,981 patients in the ARDSexp group. The OR of mortality in ARDSp group compared to the ARDSexp group was 1.11 (95% CI, 0.88 to 1.39), as determined by the random-effects model; 1.04 (95% CI, 0.92 to 1.18), as determined by the fixed-effects model; and 1.04 (95% CI, 0.92 to 1.18), as determined by the exact method, indicating that mortality is similar in the two groups. The mortality was no different whether the studies were classified as prospective (OR, 1.15; 95% CI, 0.87 to 1.51) or retrospective (OR, 1.01; 95% CI, 0.61 to 1.69); small (OR, 1.11; 95% CI, 0.77 to 1.60) or large (OR, 1.1; 95% CI, 0.82 to 1.49); or observational (OR, 1.10; 95% CI, 0.82 to 1.49) or interventional (OR, 0.97; 95% CI, 0.79 to 1.19). There was methodological and statistical heterogeneity (I(2), 50.9%; 95% CI, 21.3 to 66.2%; chi(2) statistic, 67.22; p = 0.0004).


CONCLUSIONS
The results of this study suggest that there is no difference in mortality between these two groups. Further studies should focus on specific etiologies within the subgroups rather than focusing on the broader division of ARDSp and ARDSexp.
22757148
Involvement of singlet oxygen in chloroaluminum phthalocyanine tetrasulfonate-mediated photoenhancement of lipid peroxidation in rat epidermal microsomes.
In recent studies chloroaluminum phthalocyanine tetrasulfonate (AlPCTS) has been shown to be an effective photosensitizer for the tumor necrosis in a modality known as photodynamic therapy, but the mechanism of photodynamic effect of AlPCTS is poorly understood. In this study, in vitro incubation of rat epidermal microsomes with AlPCTS followed by exposure to red light (approximately 675 nm) resulted in an increase in ADP/iron-supported lipid peroxidation, a measure of membrane damage. This photodestructive effect was found to be dependent on both the duration of light exposure and the dose of AlPCTS. Studies employing various quenchers of reactive oxygen species revealed that scavengers of singlet oxygen (histidine, 2,5-dimethylfuran, beta-carotene and sodium azide) afforded substantial protection (up to 90%) of photoenhancement whereas the scavengers of hydrogen peroxide (catalase), superoxide anion (superoxide dismutase), and hydroxyl radical (sodium benzoate, mannitol and ethanol) were ineffective in this regard. Our data indicate that AlPCTS-mediated photodestruction mainly involves a type II reaction via singlet oxygen formation and suggest that the latter could play a significant role in the tumor necrosis evoked by AlPCTS and light.
7916758
Chlorthalidone for Poorly Controlled Hypertension in Chronic Kidney Disease: An Interventional Pilot Study
To test the hypothesis that thiazide-type diuretics effectively lower blood pressure (BP) in moderate to advanced chronic kidney disease (CKD; estimated GFR 20-45 ml/min/ 1.73 m2), after confirming poorly controlled hypertension with 24-hour ambulatory BP monitoring, chlorthalidone was added to existing medications in a dose of 25 mg/day, and the dose doubled every 4 weeks if the BP remained elevated. The average age of the 14 subjects was 67.5 years, a median of 4 antihypertensive drugs were used and estimated GFR was 26.8 ± 8.8 ml/min/1.73 m2. Twelve subjects completed the 12-week treatment phase, and the 24-hour BP, which was 143.1/75.1 mm Hg at baseline, was reduced by 10.5/ 3.1 mm Hg (p = 0.01/p = 0.17). Home BP prior to initiating chlorthalidone was 152.4/82.6 mm Hg and fell at 4, 8, and 12 weeks by 10.2/4.8, 13.4/6.0, and 9.4/3.7 mm Hg (all p < 0.05). Maximal reduction in body weight and total body volume (measured by air displacement plethysmography) was seen at 8 weeks, concurrent with the maximal elevation in serum creatinine concentration and plasma renin activity. Albuminuria was significantly reduced by 40-45%. Adverse events were seen following chlorthalidone therapy in 7 subjects who experienced 18 events as follows: hypokalemia (n = 4), hyperuricemia (4), hyponatremia (3), transient creatinine changes (3), dizziness (2), hyperglycemia (1), and constipation (1). One subject had ischemic stroke during the study. In conclusion, among people with moderate to advanced CKD with poorly controlled hypertension, chlorthalidone may significantly reduce BP via volume contraction; a randomized trial is needed to define the risks and benefits. Adverse effects may occur within a few weeks and should be carefully monitored.
20137332
The unrecognized skeletal components of the cleft lip nose deformity.
37510627
Evidence for the involvement of singlet oxygen in the photodestruction by chloroaluminum phthalocyanine tetrasulfonate.
In recent years, choloroaluminum phthalocyanine tetrasulfonate (A1PCTS) has been shown to be a promising photosensitizer for the photodynamic therapy (PDT) of cancer. Although its mechanism of photodynamic action is not well defined, A1PCTS is going to be under clinical trials of PDT. In this study, in vitro addition of A1PCTS to a suspension of rat epidermal microsomes followed by irradiation with red light (approximately 675 nm) resulted in significant destruction of cytochrome P-450 and associated monooxygenase activities. The photodestructive effect was dependent on both the dose of A1PCTS and the duration of light exposure. Studies using various quenchers of reactive oxygen species showed that only scavengers of singlet oxygen such as histidine, 2,5-dimethylfuran, beta-carotene and sodium azide afforded substantial protection against photodestruction. Our data indicate the direct involvement of singlet oxygen in the A1PCTS-mediated photodestructive process.
21916120
Treated hypertension and the white coat phenomenon: Office readings are inadequate measures of efficacy.
To better define the prevalence of white coat hypertension (WCH) among patients with type 2 diabetes mellitus and to estimate the magnitude of white coat effect (WCE), before and after antihypertensive therapy, we gathered data from an open-label forced-titration study of a combination of antihypertensive drugs that was titrated sequentially, in the order amlodipine, olmesartan, and hydrochlorothiazide, over an 18-week period among 187 patients with type 2 diabetes mellitus. WCH was defined as daytime ambulatory blood pressure (BP) of 135/85 mm Hg or less, but clinic BP of 140/90 mm Hg or more. WCE was obtained as the mean difference between clinic and daytime ambulatory BP. At baseline, the prevalence of WCH was 12%; all but one subject had WCE of >10/5 mm Hg. After treatment, the prevalence of WCH had increased to 39% (P < .001). In the overall population, at baseline, the mean (±SD) WCE for systolic BP was 10.4 ± 10.9 mm Hg and 3.7 ± 8.6 mm Hg for diastolic BP. After treatment, the reduction in systolic WCE was 3.01 ± 0.93 (SE; P < .0001); no reduction was seen for diastolic WCE. Among patients treated with amlodipine-olmesartan combination, WCE at baseline was 11 mm Hg systolic and was attenuated to -0.9 mm Hg. Among patients treated with amlodipine-olmesartan-hydrochlorothiazide combination, systolic WCE was similar at baseline (10.1 mm Hg) and at end of therapy (8.1 mm Hg). Mean systolic difference between dual and triple therapy of 9.9 mm Hg, SE 2.98 was significant (P < .001). The drop in diastolic WCE from 6.4 with dual therapy to -1.2 with triple therapy was also significant (mean difference 7.6, SE 2.2; P < .001). In conclusion, the prevalence of WCH increases three-fold with treatment as a result of fewer patients having sustained hypertension. Thus, out-of-office BP monitoring especially among treated hypertensive patients with type 2 diabetes is necessary to provide better assessment of overall BP and response to treatment.