Targeted resuscitation improves coagulation and outcome.

BACKGROUND: Acute trauma coagulopathy in seriously injured casualties may be initiated by tissue hypoperfusion. A targeted (or novel hybrid [NH]) resuscitation strategy was developed to overcome poor tissue oxygen delivery associated with prolonged hypotension. METHODS: Under the Animals (Scientific Procedures) Act 1986, terminally anesthetized large white pigs were divided into four groups (n = 6). Groups 1 and 2 received blast injury and 3 and 4 no blast (sham). All were given a controlled hemorrhage (35% blood volume) and an uncompressed grade IV liver injury. Five minutes later, all were resuscitated with 0.9% saline to a systolic arterial pressure (SAP) of 80 mm Hg. After 60 minutes, the NH groups (1 and 3) were resuscitated to a SAP (110 mm Hg), whereas hypotensive groups (2 and 4) continued with SAP 80 mm Hg for up to 8 hours from onset of resuscitation. RESULTS: Mean survival time was shorter in group 2 (258 minutes) compared with groups 1, 3, and 4 (452 minutes, 448 minutes, and 369 minutes). By the end of the study, hypotension was associated with a significantly greater prothrombin time (1.73 ± 0.10 and 1.87 ± 0.15 times presurgery, groups 2 and 4) compared with NH (1.44 ± 0.09 and 1.36 ± 0.06, groups 1 and 3, p = 0.001). Blast versus sham had no significant effect on prothrombin time (p = 0.56). Peak levels of interleukin 6 were significantly lower in NH groups. Arterial base excess was significantly lower with hypotension (-18.4 mmol/L ± 2.7 mmol/L and -12.1 mmol/L ± 3.2 mmol/L) versus NH (-3.7 mmol/L ± 2.8 mmol/L and -1.8 mmol/L ± 1.8 mmol/L, p = 0.0001). Hematocrit was not significantly different between groups (p = 0.16). CONCLUSION: Targeted resuscitation (NH) attenuates the development of acute trauma coagulopathy and systemic inflammation with improved tissue perfusion and reduced metabolic acidosis in a model of complex injury. This emphasizes the challenge of choosing a resuscitation strategy for trauma patients where the needs of tissue perfusion must be balanced against the risk of rebleeding during resuscitation.

Feasibility of using rotational thromboelastometry to assess coagulation status of combat casualties in a deployed setting.

BACKGROUND: Coagulopathy in trauma patients is currently defined by the results of standard laboratory tests (prothrombin time and activated partial thromboplastin time). These results offer little in the hemostatic resuscitation that occurs in the treatment of battlefield patients who receive massive transfusions. Thromboelastometry (TEM) is a technique that can offer rapid, near-patient testing of coagulation status. METHODS: A prospective observational field study was performed in a deployed military setting to determine the feasibility of using TEM to assess the coagulation status of patients admitted to the emergency department and who subsequently received a massive transfusion. RESULTS: TEM was performed on 31 patients, 25 were direct admissions to the emergency department, 19 of whom were enrolled into the massive transfusion protocol, and 60% were involved in a blast incident. Standard laboratory testing showed that 10% of all patients were coagulopathic on admission compared with 64% with an abnormal TEM trace (p = 0.0005). All patients had abnormal maximum clot firmness. The TEM amplitude at 10 minutes is associated with the subsequent development of abnormal maximum clot firmness. Two exemplar cases are discussed, which illustrate the potential benefit of using TEM to monitor and guide and individualize therapy during a massive transfusion. CONCLUSIONS: It is feasible to use TEM in a deployed military setting. We have shown that rotational thromboelastometry significantly detects more abnormalities in the coagulation status than the standard laboratory tests (prothrombin time, and activated partial thromboplastin time).