Effect of cigarette smoking on blood coagulation

Eighteen medical students who were not smokers were asked to smoke a cigarette, inhaling as much as possible. Blood samples were obtained before and 5 minutes after smoking. A significant increase was observed in platelet adhesiveness. Whole blood coagulation time, recalcified plasma coagulation time, platelet count, partial thromboplastin time, thromboplastin generation time, and tensile strength of the clot showed changes compatible with increased coagulability; however, these were statistically not significant.