Elevated international normalised ratios correlate with severity of injury and outcome

Haemorrhagic shock is the leading cause of preventable early deaths from trauma. Acute coagulopathy on admission to a trauma unit is associated with worse outcomes. The relationship of haemorrhage to early mortality remains consistent regardless of mechanism of injury. Haemorrhage and haemorrhagic shock are increasingly amenable to interventions that result in reductions in morbidity and mortality.

To assess the prevalence of coagulopathy in patients admitted to the level 1 trauma unit at Inkosi Albert Luthuli Central Hospital, Durban, South Africa, and correlate it with in-hospital mortality.

A retrospective analysis of the first 1 000 patients admitted to the trauma unit during the years 2007 - 2011 was performed. The admission international normalised ratios (INRs) were correlated with Injury Severity Scores (ISSs) and in-hospital mortality. A multivariable Poisson model with robust standard errors was used to assess the relationship between coagulopathy and mortality after adjustment for the confounding influence of age and gender. The data were analysed using the R statistics program.

Of the 1 000 patients, 752 were male. There were 261 admissions directly from the scene and 739 inter-hospital transfers (non scene). The mean INRs among survivors for all, scene and non-scene patients were 1.33, 1.30 and 1.34, respectively, and those among non-survivors 1.92, 2.01 and 1.88, respectively (p<0.001). The overall prevalence of coagulopathy was 48.7%, 46.9% in scene patients and 49.2% in non-scene patients. The mortality rate of scene patients with abnormal INR levels was 41.1% (adjusted relative risk (aRR) 3.59, 95% confidence interval (CI) 2.11 - 6.44; p<0.001) v. 25.1% for non-scene patients (aRR 1.67, 95% CI 1.15 - 2.05; p=0.004) (p=0.001).

There was a high prevalence of coagulopathy in our study. Raised admission INRs were associated with worse outcomes. There was a direct correlation between the INR and the ISS. INRs may offer predictive capabilities in resource-depleted environments where the ISS is not routinely calculated. Early recognition of acute coagulopathy may help reduce morbidity and mortality.