The first step in managing hemorrhagic shock is recognition. Ideally, This should occur before the development of hypotension. Close attention should be paid to physiological responses to low-blood volume. Tachycardia, tachypnea, and narrowing pulse pressure may be the initial signs. Cool extremities and delayed capillary refill are signs of peripheral vasoconstriction. Bleeding In the setting of trauma, an algorithmic approach via the primary and secondary surveys is suggested by ATLS. Physical exam and radiological evaluations can help localize sources of bleeding. A trauma ultrasound, or Focused Assessment with Sonography for Trauma (FAST), has been incorporated in many circumstances into the initial surveys. The specificity of a FAST scan has been reported above 99%, but a negative ultrasound does not rule out intra-abdominal pathology. With a broader understanding of the pathophysiology of hemorrhagic shock, treatment in trauma has expanded from a simple massive transfusion method to a more comprehensive management strategy of "damage control resuscitation". The concept of damage control resuscitation focuses on permissive hypotension, hemostatic resuscitation, and hemorrhage control to adequately treat the "lethal triad" of coagulopathy, acidosis, and hypothermia that occurs in trauma. Hypotensive resuscitation has been suggested for the hemorrhagic shock patient without head trauma. The aim is to achieve a systolic blood pressure of 90 mmHg in order to maintain tissue perfusion without inducing re-bleeding from recently clotted vessels. Permissive hypotension is a means of restricting fluid administration until hemorrhage is controlled while accepting a short period of suboptimal end-organ perfusion. Studies regarding permissive hypotension have yielded conflicting results and must take into account type of injury (penetrating versus blunt), the likelihood of intracranial injury, the severity of the injury, as well as proximity to a trauma center and definitive hemorrhage control. The quantity, type of fluids to be used, and endpoints of resuscitation remain topics of much study and debate. For crystalloid resuscitation, normal saline and lactated ringers are the most commonly used fluids. Normal saline has the drawback of causing a non-anion gap hyperchloremic metabolic acidosis due to the high chloride content, while lactated ringers can cause a metabolic alkalosis as lactate metabolism regenerates into bicarbonate. Recent trends in damage control resuscitation focus on "hemostatic resuscitation" which pushes for early use of blood products rather than an abundance of crystalloids in order to minimize the metabolic derangement, resuscitation-induced coagulopathy, and the hemodilution that occurs with crystalloid resuscitation. The end goal of resuscitation and the ratios of blood products remain at the center of much study and debate. A recent study has shown no significant difference in mortality at 24 hours or 30 days between ratios of 1:1:1 and 1:1:2 of plasma to platelets to packed RBCs. However, patients that received the more balanced ratio of 1:1:1 were less likely to die as a result of exsanguination in 24 hours and were more likely to achieve hemostasis. Additionally, reduction in time to first plasma transfusion has shown a significant reduction in mortality in damage control resuscitation. In addition to blood products, products that prevent the breakdown of fibrin in clots, or antifibrinolytics, have been studied for their utility in the treatment of hemorrhagic shock in the trauma patient. Several antifibrinolytics have been shown to be safe and effective in elective surgery. The CRASH-2 study was a randomized control trial of tranexamic acid versus placebo in trauma has been shown to decrease overall mortality when given in the first three hours of injury. Follow-up analysis shows additional benefit to tranexamic acid when given in the first three hours after surgery. Damage control resuscitation is to occur in conjunction with prompt intervention to control the source of bleeding. Strategies may differ depending on proximity to definitive treatment. For patients in hemorrhagic shock, early use of blood products over crystalloid resuscitation results in better outcomes. Balanced transfusion using 1:1:1 or 1:1:2 of plasma to platelets to packed red blood cells results in better hemostasis. Anti-fibrinolytic administration to patients with severe bleed within 3 hours of traumatic injury appears to decrease death from major bleed as shown in the CRASH-2 trial. Research on oxygen-carrying substitutes as an alternative to packed red blood cells is ongoing, although no blood substitutes have been approved for use in the United States. Fluid loss For patients in<unk>  due to fluid losses, the exact fluid deficit cannot be determined. Therefore, it is prudent to start with 2 liters of isotonic crystalloid solution infused rapidly as an attempt to quickly restore tissue perfusion. Fluid repletion can be monitored by measuring blood pressure, urine output, mental status, and peripheral edema. Multiple modalities exist for measuring fluid responsiveness such as ultrasound, central venous pressure monitoring, and pulse pressure fluctuation as described above. Vasopressors may be used if blood pressure does not improve with fluids. Crystalloid fluid resuscitation is preferred over colloid solutions for severe volume depletion not due to bleeding. The type of crystalloid used to resuscitate the patient can be individualized based on the patients' chemistries, estimated volume of resuscitation, acid/base status, and physician or institutional preferences. Isotonic saline is hyperchloremic relative to blood plasma, and resuscitation with large amounts can lead to hyperchloremic metabolic acidosis. Several other isotonic fluids with lower chloride concentrations exist, such as lactated Ringer's solution or PlasmaLyte. These solutions are often referred to as buffered or balanced crystalloids. Some evidence suggests that patients who need large volume resuscitation may have a less renal injury with restrictive chloride strategies and use of balanced crystalloids. Crystalloid solutions are equally as effective and much less expensive than colloid. Commonly used colloid solutions include those containing albumin or hyperoncotic starch. Studies examining albumin solutions for resuscitation have not shown improved outcomes, while other studies have shown resuscitation with hyper-oncotic starch leads to increased mortality rate and renal failure. Patients in shock can appear cold, clammy, and cyanotic. Hypothermia increases the mortality rate of patients suffering<unk> . It is advised to keep the patient warm for the sake of maintaining the temperatures of all kinds of fluids inside the patient. Monitoring parameters *Oxygen saturation by pulse oximetry (SpO2). *Respiratory rate. *Pulse rate. *Arterial blood pressure. *Pulse pressure. *Central venous pressure. *Urine output. *Base deficit and/or lactic acid. *Temperature. *Mental state. *Changes in the electrocardiogram.
Hypovolemic shock
Obstructive shock
Distributive shock
Neurogenic shock
Cryptic shock
Septic shock
Spinal shock
Vasodilatory shock