Resuscitation with whole blood or blood components improves survival and lessens the pathophysiological burden of trauma and haemorrhagic shock in a pre-clinical porcine model

Abstract

Purpose: In military trauma, disaster medicine, and casualties injured in remote locations, times to advanced medical and surgical treatment are often prolonged, potentially reducing survival and increasing morbidity. Since resuscitation with blood/blood components improves survival over short pre-surgical times, this study aimed to evaluate the quality of resuscitation afforded by blood/blood products or crystalloid resuscitation over extended 'pre-hospital' timelines in a porcine model of militarily relevant traumatic haemorrhagic shock.

Methods: This study underwent local ethical review and was done under the authority of Animals (Scientific Procedures) Act 1986. Forty-five terminally anaesthetised pigs received a soft tissue injury to the right thigh, haemorrhage (30% blood volume and a Grade IV liver injury) and fluid resuscitation initiated 30 min later [Group 1 (no fluid); 2 (0.9% saline); 3 (1:1 packed red blood cells:plasma); 4 (fresh whole blood); or 5 (plasma)]. Fluid (3 ml/kg bolus) was administered during the resuscitation period (maximum duration 450 min) when the systolic blood pressure fell below 80 mmHg. Surviving animals were culled with an overdose of anaesthetic.

Results: Survival time was significantly shorter for Group 1 compared to the other groups (P < 0.05). Despite the same triggers for resuscitation when compared to blood/blood components, saline was associated with a shorter survival time (P = 0.145), greater pathophysiological burden and significantly greater resuscitation fluid volume (P < 0.0001).

Conclusion: When times to advanced medical care are prolonged, resuscitation with blood/blood components is recommended over saline due to the superior quality and stability of resuscitation achieved, which are likely to lead to improved patient outcomes.

Keywords: Haemorrhagic shock; Porcine model; Prolonged care; Resuscitation; Trauma.

Fig. 1

A time line of the experimental protocol including blood sample time points. ‘Prolonged care’ as applied to this experimental study is defined as a delay to DCS beyond the 2 h defined in NATO medical planning guidelines 1. “Buddy Aid” Phase of 30 min, resuscitation phase of 450 min and termination of experiment at 480 min from the onset of resuscitation. DCR damage control resuscitation, DCS damage control surgery, CC critical care

Fig. 2

Quantity and effect of fluid resuscitation. A Number of boluses given from R0 to attain target SBP; B SBP before and after the following fluid bolus; C time to the subsequent bolus; D number of boluses given in the first and second hour from the onset of the resuscitation phase; E cumulative fluid total during the resuscitation phase; F arterial haemoglobin concentration

Fig. 3

Haemodynamic changes from baseline to the end of the resuscitation phase (450min) with the grey-shaded area representing the shock phase. A systolic blood pressure (SBP); B mean arterial blood pressure (MBP); and C cardiac output (CO)

Fig. 4

Oxygen transport from baseline to the end of the resuscitation phase (450min) with the grey-shaded area representing the shock phase. A Mixed venous oxygen saturation; B oxygen extraction ratio (OER); C oxygen delivery (DO₂); and D oxygen consumption (VO₂)

Fig. 5

Arterial blood biochemistry and degree of acidosis from baseline to the end of the resuscitation phase (450min) with the grey-shaded area representing the shock phase. A Actual base excess (ABE); B lactate; C pH; and D arterial partial pressure of carbon dioxide (PaCO₂)

Fig. 6

Kaplan–Meier survival curve showing the survival time from the onset of resuscitation. No Tx = No treatment group. There were no deaths in the blood/blood products groups and the survival curves overlap