The protective effect of propofol on erythrocytes during cardiopulmonary bypass.

To evaluate the relationship between erythrocyte injury and intracellular calcium ion overload, and the protective effect of propofol on erythrocytes during cardiopulmonary bypass (CPB), 40 children with congenital heart diseases who underwent surgical repair under CPB were studied. The patients were randomly divided into two groups: control group (group C) and propofol group (group P). Anesthesia was maintained in the patients in group P with 6 mg.kg-1.h-1 propofol, and those in the group C inhaled 1%-2% isoflurane. The blood samples were taken before CPB, at the 30th min of CPB, at the end of CPB, and 2 h and 24 h after CPB to measure the content of erythrocyte intracellular calcium ion (E-Ca2+), Ca(2+)-Mg(2+)-ATPase and Na(+)-K(+)-ATPase activities, index filtration of erythrocytes (IF), mean corpuscular volume (MCV) and the concentration of plasma free hemoglobin (F-HB). Results showed that in the control group, E-Ca2+, IF, MCV and F-Hb were gradually increased and Ca(2+)-Mg(2+)-ATPase and Na(+)-K(+)-ATPase activities were decreased. The increase of E-Ca2+ was linearly paralleled to IF, MCV and F-Hb. In propofol group, all the above-mentioned parameters were significantly improved (P < 0.05). This study suggests that erythrocyte injury is related to elevation of intracellular calcium during CPB and propofol has a protective effect on erythrocyte injury.