Mortality of civilian patients with suspected traumatic haemorrhage receiving pre-hospital transfusion of packed red blood cells compared to pre-hospital crystalloid

Abstract

BackgroundMajor haemorrhage is a leading cause of mortality following major trauma. Increasingly, Helicopter Emergency Medical Services (HEMS) in the United Kingdom provide pre-hospital transfusion with blood products, although the evidence to support this is equivocal. This study compares mortality for patients with suspected traumatic haemorrhage transfused with pre-hospital packed red blood cells (PRBC) compared to crystalloid.MethodsA single centre retrospective observational cohort study between 1 January 2010 and 1 February 2015. Patients triggering a pre-hospital Code Red activation were eligible. The primary outcome measure was all-cause mortality at 6 hours (h) and 28 days (d), including a sub-analysis of patients receiving a major and massive transfusion. Multivariable regression models predicted mortality. Multiple Imputation was employed, and logistic regression models were constructed for all imputed datasets.ResultsThe crystalloid (n = 103) and PRBC (n = 92) group were comparable for demographics, Injury Severity Score (p = 0.67) and mechanism of injury (p = 0.73). Observed 6 h mortality was smaller in the PRBC group (n = 10, 10%) compared to crystalloid group (n = 19, 18%). Adjusted OR was not statistically significant (OR 0.48, CI 0.19–1.19, p = 0.11). Observed mortality at 28 days was smaller in the PRBC group (n = 21, 26%) compared to crystalloid group (n = 31, 40%), p = 0.09. Adjusted OR was not statistically significant (OR 0.66, CI 0.32–1.35, p = 0.26). A statistically significant greater proportion of the crystalloid group required a major transfusion (n = 62, 60%) compared to the PRBC group (n = 41, 40%), p = 0.02. For patients requiring a massive transfusion observed mortality was smaller in the PRBC group at 28 days (p = 0.07).ConclusionIn a single centre UK HEMS study, in patients with suspected traumatic haemorrhage who received a PRBC transfusion there was an observed, but non-significant, reduction in mortality at 6 h and 28 days, also reflected in a massive transfusion subgroup. Patients receiving pre-hospital PRBC were significantly less likely to require an in-hospital major transfusion. Further adequately powered multi-centre prospective research is required to establish the optimum strategy for pre-hospital volume replacement in patients with traumatic haemorrhage.

Pre‐hospital transfusion of red blood cells. Part 2: A systematic review of treatment effects on outcomes

“…However, in six other studies reporting matched or adjusted data, no significant effect on mortality was found, either at 3 hours, 6 hours, 24 hours, 28 days or 30 days post‐infusion, for in‐hospital mortality or overall mortality (Table ). Conversely, Kim et al found significantly lower mortality at 24 hours and a lower mortality overall for patients transfused with both PHT‐plasma and PHTRBC compared with patients receiving PHTRBC only.…”

“…Five analyses found the RBC requirement in‐hospital or in the first 24 hours to be significantly higher for PHTRBC patients, whereas five others found it to be significantly lower . One of these studies noted that taking the prehospital transfused volume into account, the cumulative 24 hours RBC requirement was not significantly different .…”

“…Blunt injury was most prevalent in the included studies, ranging from 55% to 100% of trauma patients . The mean or median injury severity score (ISS) varied from 18 to 43 (Table ) . The most frequent mechanisms of injury were motor vehicle collisions (42%‐88%) and falls from a height (3.4%‐13%) …”

“…The mean or median injury severity score (ISS) varied from 18 to 43 (Table ) . The most frequent mechanisms of injury were motor vehicle collisions (42%‐88%) and falls from a height (3.4%‐13%) …”

“…In the first 24 hours after admission to hospital, civilian patients received a median of 0 to 14 U of RBC, and paediatric patients received a mean of 3.6 U …”