Evaluation of alcohol intoxication on primary and secondary haemostasis - results from comprehensive coagulation testing.

Background: Alcohol intoxication is known to affect blood coagulation. The specific effects remain poorly understood. Here, we investigate the impact of severe alcohol intoxication on blood clotting by comprehensive coagulation testing.

Methods: A prospective study included 21 patients admitted to the emergency department of University Hospital Düsseldorf with severe alcohol intoxication (target blood alcohol concentration > 2 g/l). Platelet function and coagulation was compared between states of alcohol intoxication and soberness using multiple platelet function analysis, thrombelastography and determination of single coagulation factors. The same test panel was used to study in vitro-effects of ethanol on coagulation.

Results: Blood alcohol was correlated with impaired platelet aggregation determined in vivo by functional testing employing ADP and ASPI stimulation. Blood alcohol-associated coagulation impairment was not detectable by thrombelastography or clotting factor measurements. Blood alcohol was negatively correlated with von Willebrand factor ratio and clot strength. The association of elevated blood alcohol with impaired coagulation could not be replicated in vitro.

Discussion: Our findings suggest that alcohol impairs primary hemostasis by reducing platelet function, while secondary hemostasis remains largely unaffected. Reversion of effects upon sobering suggest a rather direct impact of alcohol on platelet function. That effect was, however, not replicated in vitro possibly implicating involvement of vascular factors.

Conclusion: Blood alcohol has a potentially negative impact on platelet function, which should be considered in the clinical management of intoxicated patients, especially in emergency settings. Potential bleeding risks due to increased blood alcohol are possibly detected by analysis of platelet function, while not by thrombelastography or plasmatic coagulation tests.