Fluid Resuscitation Of Hemorrhagic Shock Research Articles

Improved survival with early fluid resuscitation following hemorrhagic shock.

Recent studies have questioned the benefits of early fluid resuscitation in hemorrhagic shock. The purpose of the current study is to evaluate the effects of early fluid resuscitation (HSE) (15 minutes), delayed fluid resuscitation (HSD) (60 minutes), and no fluid resuscitation (HSU) on cytokine levels, hepatic resting membrane potential (Em), renal function, and mortality. Eighty male Sprague-Dawley rats (350-450 g) were hemorrhaged 35% of their total blood volume and then received 40, 80, or 100 ml of crystalloid per kilogram as intravenous fluids (IVFs). The implementation of HSE resulted in stabilization of the Em (-29 mV), which was significantly different from that seen with HSD or HSU (-24 and -29 mV, respectively). The timing of resuscitation did not affect the elevation of tumor necrosis factor (TNFalpha) levels. The interleukin-6 (IL-6) levels for the HSE group were 81, 101, and 274 pg/ml for 40, 80, and 100 ml/kg, respectively. In contrast, HSD group IL-6 levels were 440, 566, and 632 pg/ml for 40, 80, and 100 ml/kg (p < 0.0001). IL-6 levels for the HSU group was 427 pg/ml, which was significantly different from that of the HSE group (p < 0.05). Urine output was present in 58% of the HSE rats but only 24% in the HSD rats and 0% of the HSU rats. Mortality was 11% for HSE, 58% for HSD, and 50% for HSU rats. Despite the recent studies questioning the benefits of early fluid resuscitation, these data show marked improvement in hepatic stability, the presence of urine output, decreased IL-6 levels, and significantly lower mortality when IVFs were given early after hemorrhagic shock. Furthermore, excessive fluid resuscitation (100 ml/kg) resulted in an increased inflammatory cytokine level and mortality and may account for the controversy.

The Comparison of the Effects of Various Crystalloid Solutions on the Resuscitation in Rabbits with Acute Hemorrhagic Shock

Background : The purpose of this study is to evaluate what kind of crystalloid solution could function as the best buffer and correct the metabolic acidosis most effectively in rabbits with hemorrhagic shock. Methods : Twenty eight rabbits were bled until mean arterial pressure(MAP) became 70% of control. Thirty minutes after hemorrhagic shock fluid resuscitation was started with either plasmalyte or Hartmann''s solution or 0.9% normal saline until MAP returned to 90% of the control. Hemodynamic and blood gas study, plasma lactate and electrolyte concentration were measured before, during, and 30 minutes after recovery from shock. Results : The amount of shed blood to reduce MAP to 70% of control ranged 76∼87 ml. And the volume for fluid resuscitation was 274∼324 ml. There was no statistically significant difference among the three groups. The pH decreased during shock in all group and still decreased after resuscitation in Hartmann''s solution and normal saline. But it increased significantly after resuscitation in plasmalyte. Lactate was increased in all group during shock and decreased by 22 and 23 mg/dl after resuscitation in plasmalyte and normal saline. But it still increased by 40 mg/dl in Hartmann''s solution. Serum potassium level decreased significantly after resuscitation with normal saline. Serum calcium level decreased significantly after resuscitation with plasmalyte and normal saline. Conclusion: With the above results the plasmalyte which has pH closer to that of normal blood might be able to avoid the metabolic acidosis and maintain acid-base equilibrium effectively after fluid resuscitation in acute hemorrhagic shock. (Korean J Anesthesiol 1998; 35: 16∼22)

Upregulation of alveolar liquid clearance after fluid resuscitation for hemorrhagic shock in rats.

The primary objective of this study was to test the hypothesis that a catecholamine-dependent mechanism would upregulate alveolar liquid clearance after fluid resuscitation from 15 min of hemorrhagic shock. Anesthetized rats were hemorrhaged to a mean arterial pressure of 35 mmHg for 15 min and were resuscitated with a 4% albumin solution. Alveolar liquid clearance was measured 5 h later by the concentration of protein in the distal airspaces over 1 h after instillation of a 5% albumin solution into one lung. Hemorrhaged rats developed a severe metabolic acidosis that was associated with a significant rise-in plasma epinephrine levels throughout the study. There was a 60% increase in alveolar liquid clearance in hemorrhaged and resuscitated rats compared with control rats. Amiloride (10(-4) or 10(-6) M), propranolol (10(-4) M), or bilateral adrenalectomy inhibited the increase in alveolar liquid clearance. This effect was reproduced by the intravenous administration of epinephrine in adrenalectomized and hemorrhaged rats. Thus these data provide evidence for a catecholamine-dependent regulation of sodium transport that protects the airspaces against flooding several hours after fluid resuscitation from hemorrhagic shock.

CONTROVERSIES IN SHOCK RESEARCH: HYPERTONIC RESUSCITATION—PROS AND CONS

The proper fluid resuscitation of hemorrhagic shock is still controversial. Hypertonic saline has been suggested for prehospital resuscitation of hemorrhagic shock, because of its superior ability to expand blood volume and elevate systemic blood pressure and cardiac output in a small volume and during a short time period. We have defined two types of hemorrhagic shock: controlled hemorrhagic shock (CHS), where the bleeding source is immediately occluded following hemorrhage, and uncontrolled hemorrhagic shock (UCHS), where bleeding is induced by injury to blood vessels that are left unoccluded. It was observed that hypertonic saline (HTS) treatment of controlled hemorrhagic shock leads to an increase in blood pressure and cardiac output, while HTS treatment of UCHS leads to increased bleeding from injured blood vessels, hemodynamic deterioration, and increased mortality. Conversion of UCHS to CHS by tourniquet, military antishock trousers, or surgical hemostasis prevented excessive bleeding and mortality following HTS. Several clinical studies have used hypertonic saline dextran (HSD) or hypertonic saline (HS) for treatment of trauma casualties, but to date no significant improvement in mortality has been demonstrated by either HS or HSD. A more favorable effect but still not statistically significant effect has been demonstrated in patients with a Glasgow Coma Scale of 8 or less. The efficacy of HS has not clearly been established in clinical trials, in all of which HS was used in combination with conventional crystalloid therapy. Further human trials are required to better define the patient population that would benefit most from the prehospital administration of HS.

Fluid resuscitation of hemorrhagic shock.

An organized, practical approach to hemorrhagic shock used at Parkland Memorial Hospital in Dallas has several notable advantages besides the primary benefit of improving survival. It greatly reduces the need for uncrossmatched blood and the possibility of transfusion reactions. Oliguric renal failure complicating shock is virtually eliminated. Rapid intravenous infusion of lactated Ringer's solution is a main feature of this technic.