Controversy in Trauma Resuscitation: Do Ratios of Plasma to Red Blood Cells Matter?

Successful recovery from delayed amniotic fluid embolism with prolonged cardiac resuscitation

Amniotic fluid embolisms (AFE) are one of the most fatal complications of pregnancy. We describe a case of AFE that occurred 2 h after vaginal delivery at 41 weeks of gestation. The diagnosis of AFE was made by symptoms of dyspnea, coagulopathy, and severe hypotension. ZnCP-1, the characteristic component of meconium, was elevated in the serum. Cardiac compressions after repeated cardiac arrests were required during the initial 2 h of resuscitation. Primary resuscitation was performed with airway management and aggressive fluid management, including infusion of 33 units of red cell concentrates and 57 units of fresh frozen plasma. The patient recovered without any aftereffects. This case report warrants that AFE should be considered when coagulopathy and dyspnea are observed during the postpartum period.

The acute management of trauma hemorrhage: a systematic review of randomized controlled trials

Introduction

Worldwide, trauma is a leading cause of death and disability. Haemorrhage is responsible for up to 40% of trauma deaths. Recent strategies to improve mortality rates have focused on optimal methods of early hemorrhage control and correction of coagulopathy. We undertook a systematic review of randomized controlled trials (RCT) which evaluated trauma patients with hemorrhagic shock within the first 24 hours of injury and appraised how the interventions affected three outcomes: bleeding and/or transfusion requirements; correction of trauma induced coagulopathy and mortality.

Methods

Comprehensive searches were performed of MEDLINE, EMBASE, CENTRAL (The Cochrane Library Issue 7, 2010), Current Controlled Trials, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform (ICTRP) and the National Health Service Blood and Transplant Systematic Review Initiative (NHSBT SRI) RCT Handsearch Database.

Results

A total of 35 RCTs were identified which evaluated a wide range of clinical interventions in trauma hemorrhage. Many of the included studies were of low methodological quality and participant numbers were small. Bleeding outcomes were reported in 32 studies; 7 reported significantly reduced transfusion use following a variety of clinical interventions, but this was not accompanied by improved survival. Minimal information was found on traumatic coagulopathy across the identified RCTs. Overall survival was improved in only three RCTs: two small studies and a large study evaluating the use of tranexamic acid.

Conclusions

Despite 35 RCTs there has been little improvement in outcomes over the last few decades. No clear correlation has been demonstrated between transfusion requirements and mortality. The global trauma community should consider a coordinated and strategic approach to conduct well designed studies with pragmatic endpoints.

Trauma-induced coagulopathy--a review of the systematic reviews: is there sufficient evidence to guide clinical transfusion practice?

Systematic reviews are accepted as a robust and less biased means of appraising and synthesizing results from high-quality studies. This report collated and summarized all the systematic review evidence relating to the diagnosis and management of trauma-related coagulopathy and transfusion, thereby covering the widest possible body of literature. We defined 4 key clinical questions: (1) What are the best methods of predicting and diagnosing trauma-related coagulopathy? (2) Which methods of clinical management correct coagulopathy? (3) Which methods of clinical management correct bleeding? and (4) What are the outcomes of transfusion in trauma? Thirty-seven systematic reviews were identified through searches of MEDLINE (1950-July 2010), EMBASE (1980-July 2010), The Cochrane Library (Issue 7, 2010), National Guidelines Clearing House, National Library for Health Guidelines Finder, and UKBTS SRI Transfusion Evidence Library (www.transfusionevidencelibrary.com). The evidence from the systematic review literature was scanty with many gaps, and we were not able to conclusively answer any of our 4 questions. Much more needs to be understood about how coagulopathy and bleeding in trauma are altered by transfusion practices and, most importantly, whether this translates into improved survival. There is a need for randomized controlled trials to answer these questions. The approach described in this report provides a framework for incorporating new evidence.

Blood product use in trauma resuscitation: plasma deficit versus plasma ratio as predictors of mortality in trauma (CME)

BACKGROUND

Resuscitation of rapidly bleeding trauma patients with units of red blood cells (RBCs) and plasma given in a 1:1 ratio has been associated with improved outcome. However, demonstration of a benefit is confounded by survivor bias, and past work from our group has been unable to demonstrate a benefit.

STUDY DESIGN AND METHODS

We identified 438 adult direct primary trauma admissions at risk for massive transfusion who received 5 or more RBC units in the first 24 hours and had a probability of survival of 0.010 to 0.975. We correlated survival with RBC and plasma use by hour, both as a ratio (units of plasma/units of RBC) and as a plasma deficit (units of RBC - units of plasma) in the group as a whole and among those using 5 to 9 and more than 9 units of RBCs.

RESULTS

Resuscitation was essentially complete in 58.3% by the end of the third hour and 77.9% by the end of the sixth hour. Mortality by hour was significantly associated with worse plasma deficit status in the first 2 hours of resuscitation (p < 0.001 and p < 0.01) but not with plasma ratio. In a subgroup with a Trauma Revised Injury Severity Score of 0.200 to 0.800, early plasma repletion was associated with less blood product use independently of injury severity (p < 0.001).

CONCLUSIONS

1) The efficacy of plasma repletion plays out in the first few hours of resuscitation, 2) plasma deficit may be a more sensitive marker of efficacy in some populations, and 3) early plasma repletion appears to prevent some patients from going on to require massive transfusion.

Damage control in trauma and abdominal sepsis

Damage control surgery, initially formalized <20 yrs ago, was developed to overcome the poor outcomes in exsanguinating abdominal trauma with traditional surgical approaches. The core concepts for damage control of hemorrhage and contamination control with abbreviated laparotomy followed by resuscitation before definitive repair, although simple in nature, have led to an alteration in which emergent surgery is handled among a multitude of problems, including abdominal sepsis and battlefield surgery. With the aggressive resuscitation associated with damage control surgery, understanding of abdominal compartment syndrome has expanded. It is probably through avoiding this clinical entity that the greatest improvement in surgical outcomes for various emergent surgical problems has occurred in the past two decades. However, with its success, new problems have emerged, including increases in enterocutaneous fistulas and open abdomens. But as with any crisis, innovative strategies are being developed. New approaches to control of the open abdomen and reconstruction of the abdominal wall are being developed from negative pressure dressing therapies to acellular allograft meshes. With further understanding of new resuscitative strategies, the need for damage control surgery may decline, along with its concomitant complications, at the same time retaining the success that damage control surgery has brought to the critically ill trauma and general surgery patient in the past few years.

Changing paradigms in surgical resuscitation

Patients undergoing emergency surgery typically require resuscitation, either because they are hemorrhaging or because they are experiencing significant internal fluid shifts. Intravascular hypovolemia is common at the time of anesthesia induction and can lead to hemodynamic collapse if not promptly treated. Central pressure monitoring is associated with technical complications and does not improve outcomes in this population. Newer modalities are in use, but they lack validation. Fluid resuscitation is different in bleeding and septic patients. In the former group, it is advisable to maintain a deliberately low blood pressure to facilitate clot formation and stabilization. If massive transfusion is anticipated, blood products should be administered from the outset to prevent the coagulopathy of trauma. Early use of plasma in a ratio approaching 1:1 with red blood cells (RBCs) has been associated with improved outcomes. In septic patients, early fluid loading is recommended. The concept of "goal-directed resuscitation" is based on continuing resuscitation until venous oxygen saturation is normalized. In either bleeding or septic patients, however, the most important goal remains surgical control of the source of pathology, and nothing should be allowed to delay transfer to the operating room. We review the current literature and recommendations for the resuscitation of patients coming for emergency surgery procedures.