Biswadev Mitra

Fresh frozen plasma (FFP) use during massive blood transfusion in trauma resuscitation.

INTRODUCTION Recent retrospective studies have found high fresh frozen plasma (FFP) to packed red blood cell (PRBC) ratios during trauma resuscitation to be associated with improved mortality. Whilst this association may be related to a mortality bias present in these studies, there has been an overall tendency towards a 1:1 FFP:PRBC ratio in massive transfusion guidelines worldwide. The aim of this study was to retrospectively review the administration of FFP in patients undergoing massive transfusion during trauma resuscitation, to add to the evidence base for massive transfusion guidelines. MATERIALS AND METHODS Multi-trauma patients who were administered blood transfusions of 5units or more of packed red blood cells (PRBCs) in the first 4h were included in this study. Mortality was the primary endpoint with length of hospital stay, ICU hours and mechanically ventilated hours secondary endpoints. RESULTS There were 331 patients included in this study with a median Injury Severity Score (ISS) of 36 (25-50) and a mortality of 29.9%. There was little change in the ratio of FFP:PRBC transfused per patient from 2005 to 2008. A low FFP:PRBC ratio in the first 4h of resuscitation, older age, low initial GCS and coagulopathy on presentation were significant independent factors associated with mortality. When deaths in the first 24h were excluded, the FFP:PRBC ratio had no association with mortality. DISCUSSION This study has shown increased initial survival in association with higher FFP:PRBC ratios during massive transfusion in a population with a high proportion of blunt injuries. The association is difficult to interpret because of an inherent survival bias. The optimal ratio of FFP:PRBC during massive transfusion may be different to 1:1 and further prospective research is required. There is now an increasing need for well designed randomised controlled trials to determine the best FFP:PRBC ratio for the resuscitation of blunt multi-trauma patients.

Acute coagulopathy and early deaths post major trauma.

INTRODUCTION AND AIMS Acute traumatic coagulopathy is observed in 10-25% of patients post major trauma and its management forms an integral part of haemostatic resuscitation. The identification and treatment of this coagulopathy is difficult and there is uncertainty regarding optimal therapeutic guidelines during the early phases of trauma resuscitation. This study aimed to examine the association between acute coagulopathy and early deaths post major trauma. METHODS A retrospective review of data over a 5 year period was performed to determine the associations between variables considered to contribute to mortality for adult major trauma patients (Injury Severity Score (ISS)>15) receiving blood transfusions as part of their initial resuscitation. Early death, defined as death in ED, or death in the operating theatre (OT), Intensive Care Unit (ICU) or wards within 24 h of admission was the primary end-point. Patients with non-survivable head injury on initial imaging were excluded. Univariate associations were calculated and multivariable logistic regression analysis was used to determine independent associations with mortality. RESULTS There were 772 patients included in this study with a median ISS of 29 (19-41), with 91.7% blunt trauma. All-cause in-hospital mortality was 17.5%, while 77 (9.7%) patients died early. Increasing age (OR 1.04), a GCS of 3-8 (OR 5.05), and the presence of acute coagulopathy (OR 8.77) were significant independent variables associated with early death. CONCLUSIONS Acute traumatic coagulopathy, independent of injury severity, transfusion practice or other physiological markers for haemorrhage, was associated with early death in major trauma patients requiring a blood transfusion. Early recognition and management of coagulopathy, independent of massive transfusion guidelines, may improve outcome from trauma resuscitation. Further studies are required for the early recognition of acute traumatic coagulopathy to enable the development of an evidence base for management.

The definition of massive transfusion in trauma: a critical variable in examining evidence for resuscitation.

Objectives ‘Massive’ transfusion is a poorly defined inclusion criteria for studies examining the blood and blood product that are used during trauma resuscitation. We aimed to compare the traditional definition of massive transfusion (≥10 units in 24 h) to a more acute definition of at least 5 units in 4 h. Methods Multitrauma patients were subgrouped according to the traditional definition and compared with the acute definition. Demographics, presenting vital signs and blood results, management including transfusion practice and outcomes were retrospectively studied. Associations of transfused fresh frozen plasma:packed red blood cells (PRBC) ratios with mortality were studied. Results There were 927 patients who received PRBCs in the first 24 h, with 314 patients identified using the traditional definition and 303 patients using the acute definition. The patients identified using the traditional definition received 18 (12–29) units of PRBC in 24 h, significantly higher than those identified using the acute definition [15 (9–29) units, P<0.001]. The traditional definition excluded a significant proportion of patients who died in the emergency department. By using the acute definition to select a study sample, there seems to be an increase in mortality with fresh frozen plasma:PRBC ratio of 1 : 1 ratio compared with a 1 : 2 ratio. Conclusion The traditional ‘massive’ transfusion definition not only ‘dilutes’ the potential study samples with a less acute group of patients, but also further excludes patients who die early. This latter group is most likely to be benefitted from any change to resuscitation practice. An acute definition of massive transfusion should be adopted when examining clinical practice during initial trauma resuscitation.

Acute traumatic coagulopathy in the setting of isolated traumatic brain injury: A systematic review and meta-analysis

BACKGROUND AND OBJECTIVES Acute traumatic coagulopathy (ATC) has been reported in the setting of isolated traumatic brain injury (iTBI) and associated with high mortality and poor outcomes. The aim of this systematic review was to examine the incidence and outcome of patients with ATC in the setting of iTBI. METHODS We conducted a search of the MEDLINE database and Cochrane library, focused on subject headings and keywords involving coagulopathy and TBI. Design and results of each study were described. Studies were assessed for heterogeneity and the pooled incidence of ATC in the setting of iTBI determined. Reported outcomes were described. RESULTS There were 22 studies selected for analysis. A statistically significant heterogeneity among the studies was observed (p<0.01). Using the random effects model the pooled proportion of patients with ATC in the setting of iTBI was 35.2% (95% CI: 29.0-41.4). Mortality of patients with ATC and iTBI ranged between 17% and 86%. Higher blood transfusion rates, longer hospital stays, longer ICU stays, decreased ventilator free days, higher rates of single and multiple organ failure and higher incidence of delayed injury and disability at discharge were reported among patients with ATC. CONCLUSIONS ATC is commonly associated with iTBI and almost uniformly associated with worse outcomes. Any disorder of coagulation above the normal range appears to be associated with worse outcomes and therefore a clinically important target for management. Earlier identification of patients with ATC and iTBI, for recruitment into prospective trials, presents avenues for further research.

Fluid resuscitation in major burns.

Background:  The Parkland formula is established as the ‘gold standard’ for initial fluid resuscitation for major burns. The purpose of this study was to review our fluid resuscitation practice for major burns to determine whether anecdotal observations of significant variations from the Parkland formula were wide spread and whether any difference could be used as a basis for a revision of fluid resuscitation in major burns.

Early prediction of acute traumatic coagulopathy

INTRODUCTION The inability to accurately predict acute traumatic coagulopathy (ATC) has been a key factor in the low level of evidence guiding its management. The aim of this study was to develop a tool to accurately identify patients with ATC using pre-hospital variables without the use of pathology or radiological testing. METHODS Retrospective data from the trauma registry on major trauma patients were used to identify variables independently associated with coagulopathy. These variables were clinically evaluated to develop a scoring system to predict ATC, which was prospectively validated in the same setting. RESULTS There were 1680 major trauma patients in the derivation dataset, with 151 patients being coagulopathic. Pre-hospital variables independently associated with ATC were entrapment (OR 1.85; 95% CI: 1.12-3.06), temperature (OR 0.60; 95% CI: 0.60-0.72), systolic blood pressure (OR 0.99; 95% CI: 0.98-0.99), abdominal or pelvic content injury (OR 2.0; 95% CI: 1.27-3.12) and pre-hospital chest decompression (OR 4.99; 2.77-8.99). The COAST score was developed, scoring points for entrapment, temperature <35°C, systolic blood pressure < 100 mm Hg, abdominal or pelvic content injury and chest decompression. Prospectively validated using 1225 major trauma patients, a COAST score of ≥ 3 had a specificity of 96.4% with a sensitivity of 60.0%, with an area under the receiver operating characteristic curve of 0.83 (0.78-0.88). CONCLUSIONS The COAST score accurately identified a group of patients with ATC using pre-hospital observations. This predictive tool can be used to select patients for inclusion into prospective studies examining management options for ATC. Mortality in these patients is high, potentially improving feasibility of outcome studies.

Review article: Shock Index for prediction of critical bleeding post‐trauma: A systematic review

Early diagnosis of haemorrhagic shock (HS) might be difficult because of compensatory mechanisms. Clinical scoring systems aimed at predicting transfusion needs might assist in early identification of patients with HS. The Shock Index (SI) – defined as heart rate divided by systolic BP – has been proposed as a simple tool to identify patients with HS. This systematic review discusses the SIs utility post‐trauma in predicting critical bleeding (CB). We searched the databases MEDLINE, Embase, CINAHL, Cochrane Library, Scopus and PubMed from their commencement to 1 September 2013. Studies that described an association with SI and CB, defined as at least 4 units of packed red blood cells (pRBC) or whole blood within 24 h, were included. Of the 351 located articles identified by the initial search strategy, five met inclusion criteria. One study pertained to the pre‐hospital setting, one to the military, two to the in‐hospital setting, and one included analysis of both pre‐hospital and in‐hospital values. The majority of papers assessed predictive properties of the SI in ≥10 units pRBC in the first 24 h. The most frequently suggested optimal SI cut‐off was ≥0.9. An association between higher SI and bleeding was demonstrated in all studies. The SI is a readily available tool and may be useful in predicting CB on arrival to hospital. The evaluation of improved utility of the SI by performing and recording at earlier time‐points, including the pre‐hospital phase, is indicated.

Predicting massive blood transfusion using clinical scores post‐trauma

Background and Objectives  Early prediction of massive transfusion (MT) post‐trauma may reduce mortality by earlier delivery of blood products. A clinical prediction tool (PWH score) for this purpose was developed at the Prince of Wales Hospital, Hong Kong. The aims of this study were to apply this tool to major trauma patients in Victoria, Australia and compare the score to the Assessment of Blood Consumption (ABC) score and the Trauma‐Associated Severe Haemorrhage (TASH) score.

Trauma patients with the ‘triad of death’

Introduction Injured patients presenting with hypothermia, acidosis and coagulopathy have been identified at high risk of death. This study aimed to describe the presentation, management and outcome of major trauma patients presenting with the ‘triad of death’ and identify ways to improve survival. Methods A retrospective, explicit chart review was undertaken on patients presenting to a level I adult major trauma centre with the ‘triad of death’. These patients presented directly from the scene, were coagulopathic (international normalised ratio (INR) >1.5), hypothermic (temperature <35°C) and acidotic (pH <7.2) on arrival. Results There were 90 patients over an 8-year period, with an overall mortality of 47.8%. No significant differences were observed among demographics and injury severity scores between survivors and non-survivors. Extremes of systolic blood pressure and heart rate, a high activated partial thromboplastin time activated partial thromboplastin time, low fibrinogen counts, pH, bicarbonate, base excess and haemoglobin were present among survivors. There were no survivors in our cohort with an initial INR greater than 3.2. Survivors received significantly lower volumes of packed red blood cells. Conclusions There has been little change in mortality over time in this subgroup of major trauma patients. While the presence of the triad alone does not determine futility, there were no survivors over 8 years with extreme coagulopathy with concurrent hypothermia and acidosis.

The utility of a shock index ≥ 1 as an indication for pre-hospital oxygen carrier administration in major trauma.

INTRODUCTION AND AIMS The use of intravenous oxygen carriers (packed red blood cells (PRBC), whole blood and synthetic haemoglobins (HBOCs) for selected pre-hospital trauma resuscitation cases has been reported, despite a lack of validated clinical indications. The aim of this study was to retrospectively identify a sub-group of adult major trauma patients most likely to benefit from pre-hospital oxygen carrier administration and determine the predictive relationship between pre-hospital shock index (SI) [pulse rate/systolic blood pressure] and haemorrhagic shock, blood transfusion and mortality. METHODS A retrospective review of adult major trauma patients recorded in The Alfred Trauma Registry was conducted. Patients were included if they received at least 1L of pre-hospital crystalloid and spent over 30 min in transit. The association of shock index and transfusion was determined. Patients were further sub-grouped by mode of transport to determine the population of trauma patients who could be included into prospective studies of intravenous oxygen carriers. RESULTS There were 1149 patients included of whom 311 (21.9%) received an acute blood transfusion. The SI correlated well with transfusion practice. A SI ≥ 1.0, calculated after at least 1L of crystalloid transfusion, identified patients with a high specificity (93.5%; 95% CI: 91.8-94.8) for receiving a blood transfusion within 4h of hospital arrival. While patients transported by helicopter had higher injury severity and blood transfusion requirement, there were no difference in physiological variables and outcomes when compared to patients transported by road car. CONCLUSIONS A shock index ≥ 1.0 is an easily calculated variable that may identify patients for inclusion into trials for pre-hospital oxygen carriers. Shocked patients have high mortality rates whether transported by road car or by helicopter. The efficacy of pre-hospital intravenous oxygen carriers should be trialled using a shock index ≥ 1.0 despite fluid resuscitation as the clinical trigger for administration.