Coagulopathy Is a Strong Independent Predictor Of In-Hospital Mortality Following Massive Transfusion: Initial Results From The Australian and New Zealand Massive Transfusion Registry (ANZ-MTR)

In trauma, the presence of coagulopathy with or without critical bleeding (CB) is associated with poorer outcomes. However in non-trauma patients, it is unknown what proportion of CB patients are coagulopathic. We aimed to characterise the presence of coagulopathy in a representative cohort of massive transfusion (MT) recipients and explore what factors, including coagulopathy, were associated with in-hospital mortality.

The Australian and New Zealand Massive Transfusion Registry (ANZ-MTR), established in 2011, collects information on CB in all clinical contexts. In the pilot phase, all adult CB patients who received a MT (defined as ≥5 units of red blood cells [RBC] in 4hrs) were identified at 9 Australian hospitals. Transfusion history, laboratory results and hospital administrative data were extracted. Coagulopathy was defined as INR >1.5 or aPTT >60 s using the most recent laboratory test results following the onset of MT (post-MT). The association between mortality and patient characteristics and therapy were explored using multiple logistic regression.

A total of 1263 MT cases occurred in 1242 patients (1% had 2x MTs). Median age was 64 (IQR 49-76) years; 64% were male. The majority of cases of CB were surgical (total 55%) followed by GI bleeding (17%). Of the 1147 (91%) MT cases with an aPTT or INR result available post-MT, 37% (n=472) were coagulopathic. Of these, 44% (n=209) were also coagulopathic preceding the onset of MT (pre-MT). Of the total group, 474 (38%) had no recorded pre-MT coagulation results. Patient characteristics are presented in Table 1. Presence of coagulopathy post-MT was associated with surgical causes of CB, low post-MT Hb level, higher use of all fresh blood components, increased prothrombinex use and in-hospital mortality. Independent predictors of in-hospital mortality following multivariate logistic regression were coagulopathy (OR= 2.94; 95%CI=2.09-4.16, p<0.001), certain causes of CB including medical (mainly hem/onc & liver disease; OR= 4.63; 95%CI=1.85-11.60, p=0.001), vascular surgery (OR= 2.44; 95%CI=1.27-4.66, p=0.007), GI bleeding (OR= 2.12; 95%CI=1.31-3.43, p=0.002), liver surgery (OR= 0.40; 95%CI=0.18-0.90, p=0.03), age (OR= 1.02; 95%CI=1.01-1.03, p<0.001), and units of RBC (OR= 1.01; 95%CI=1.00-1.02, p=0.03) and cryo (OR= 1.02; 95%CI=1.00-1.03, p<0.001).

Presence of coagulopathy early in MT varied accordingly to clinical context, with surgical causes of CB having the highest rates of coagulopathy and obstetric haemorrhage the lowest. Coagulopathy remained a predictor of in-hospital mortality independent of the clinical context. Data generated by the Australian and New Zealand Massive Transfusion Registry, provides a unique opportunity to explore differences in the pathophysiology of CB across clinical settings and the management and outcomes of this diverse patient population.

Zatta:CSL Behring: Research Funding. Andrianopoulos:Monash University: Consultancy, Honoraria. Phillips:CSL Behring: Research Funding. Isbister:Johnson & Johnson: Honoraria. Wood:CSL Behring: Research Funding.