Different hypotensive responses to intravenous bovine and human thrombin preparations in swine

Background: Accidental intravenous introduction of commercial bovine thromb in (BT) during use of fibrin glue may result in profound hypotension. Comme rcial human thrombin (HT) is now available. This study compared the effects of intravenous BT versus HT in swine. Methods: Swine received 30 U/kg BT, 60 U/kg BT, 30 U/kg HT, or 60 U/kg HT i ntravenously. Mean arterial pressure (MAP) and survival were monitored for 30 minutes. Thrombin purities and in vitro activities were examined, Results: MAP nadir was lower (p < 0.05) after BT, 27.7 +/- 3.3% (mean +/- S EM) of pretreatment MAP, compared,vith 41.1 +/- 3.7% after HT, Five of six animals died after 60 U/kg BT, whereas all others survived (p < 0.05), Hist ology suggested more severe disseminated intravascular coagulation after BT , HT was purer than BT, In vitro activities were similar. Conclusion: Both BT and HT produced hypotension. HT appeared safer, because of higher purity, Regardless of source and purity, thrombin must be used w ith caution.