[Can administration of trasylol in reduced Hammersmith dosage with simultaneous transfusion of autologous blood meet the requirements of open heart surgery?].

Problem: The general positive effect of the proteinase inhibitor trasylol on blood loss and transfusion demand in cardiac surgery has been demonstrated in several placebo-controlled studies. Given the possibility of cardiac and renal side effects associated with a high dose of trasylol (Hammersmith dosage: 6 x 10(6) kallikrein inactivator units KIU), the question of a dose reduction was raised.

Methods: Being designed as a randomized double-blind comparative group study, the investigation included 120 patients with elective primary cardiac surgery from November 1990 to April 1992. One characteristic aspect of this study was the combined administration of trasylol and autologous blood transfusions. To compare the efficacy and safety of different doses of trasylol, two groups, each with 60 patients, were created: the former with the full Hammersmith dose (high dose group = HD group), the latter with half of the Hammersmith dose (los dose group = LD group). A placebo group had to be excluded for ethical reasons.

Results: The trasylol plasma levels showed a good dose correlation for the complete interval. The intra-operative bleeding tendency, as judged by the surgeons in charge, did not show any statistical significant difference between the HD group and the LD group. As to the post-operative blood loss via thoracic drainage, the early collection periods did not show any difference between both study groups. Starting at 6 hours post-operatively, the drainage losses showed a tendency towards lower volumes in the HD group. This difference was statistically significant for the time period "6-12 hours post-operatively". The analysis of the post-operative complications did not show any difference.

Summary: In this study with a high percentage of autologous blood transfusions, a lower dose of trasylol seemed to be nearly as effective as a full Hammersmith dose. However, such a reduced dose did not demonstrate any advantage regarding the complication rate in comparison with the conventional high dose.