Effects of Prostacyclin on Heparin Reversal with Protamine

Abstract

This study was planned to show the beneficial effects of prostacyclin (PGI2) utilization on adverse effects of protamine. PGI2 was administered at a rate of 5 ng/kg/min. Twenty patients entered this study. Half of them received PGI2 whereas the others did not. Right ventricular end-diastolic volume index and right ventricular stroke work index were 72 mL/m2 and 2.2 g.m/m2, respectively, after patients were weaned off the bypass and 79 and 1.5, respectively, at five minutes after pro tamine administration in the control group; these values were 88 and 3.2, re spectively, and 86 and 3, respectively, in the PGI2 group. Left ventricular stroke work index (g.m/m2) was 27.9 in the control group and 36.7 in the PGI2 group (p < 0.05) after protamine administration. Thromboxane B2 levels (pmoL/mL) in coronary sinus (CS) blood were 251 in the control group and 90 in the PGI2 group at five minutes after protamine administration (p < 0.05). Myocardial blood flow was 174 mL in the control group and 245 mL in the PGI2 group at five minutes after protamine adminis tration (p < 0.05). Cyclic adenosine monophosphate (cAMP) and cyclic guano- sine monophosphate (cGMP) levels in CS blood were 17 pmoL/mL and 2.1 pmoL/mL, respectively, in the control group and 36 and 0.3, respectively, in the PGI2 group at five minutes after protamine administration. Leukotriene B4 level was 129 and 57 pmoL/mL in the control and PGI2 groups, respectively (at the same time as the cAMP measurement) (p < 0.05). From the results of this study the authors conclude that adverse effects of heparin reversal with protamine can be reduced with the use of PGI2.

Beneficial Effects of Aminophylline on Ischemia-Reperfusion in Isolated Rabbit Heart

“…In previous studies, it was shown that aminophylline and prostacyclin protected the heart from protamine cardiotoxicity by elevating the cAMP level. 14,15 The most marked effects of aminophylline were observed during the early reperfusion period in terms of volume-pressure relationship and myocardial metabolism. In group 2 under maximal volume loading conditions, there was better contractile activity, increased oxidative activity, and less lactate release compared with the other groups, indicating reduced injury.…”