Assessment of liver function test change after open heart surgery

ABSTRACT

Open heart surgery requires using cardiopulmonar bypass [CPB]. CPB stimulates complement, coagulation and immune systems and non-pulsatile flow has an important effect on body organs, like liver. Activation of this system produces severe inflammatory reaction with subsequent organ damage. This study was designated to examine the influence of CPB on simple liver function test. A total of 100 patients with coronary artery disease [CAD] and valvular heart disease were scheduled for surgery and entered in a clinical study to assess the effects of intra-operative variables on simple liver function tests [SGOT, SGPT, alkaline phosphatase, and bilirubin] measured after three consecutive days with an auto-analyzer device. Patients with a past medical history of right heart failure, jaundice or hepatitis were excluded from our study. Independent and continuous variables, such as age, gender, pump time, temperature in pump, transfusion, were measured and recorded, and effect of these variables on mean values of liver function test after operation was evaluated by generalized linear method [GLM] and two way methods. This test entered to model as dependent variables and other variables as fixed or co-variables. The mean values of liver function test before and after operation were compared by ANOVA and Turkey's post hoc test and p-value <0.05 was considered significant. The pump hypotension [BP<50mmHg] had an effect on SGPT 1 and SGOT 2 and SGOT 3 [P<0.004]. Change of SGOT 2 test was significant in the pump time longer than 100 minutes. SGOT 1, SGOT 3, SGPT 1, alkaline phosphatase 1 changes related to CPB temperature was seen in temperature less than 28, rise of alkaline phosphatase 1,2, 3 was significant [P<0.01] with long anesthesia time. Type of operation had a significant effect on direct bilirubin 2, 3 and type of pump had an effect on SGOT 2 and direct bilirubin 1. Sex had effect on SGOT 2 but age did not have any effect on liver function test. Transfusion volume raised SGOT 1 and alkaline phosphatase 1 and direct bilirubin 2 and long pump time raised SGOT 2. Age had no influence on liver function test. The most sensitive tests to find hepatic injury with hypothermia were SGPT 1 and alkaline phosphstase 1 and SGOT 1. In CPB hypotension, SGPT 1, 2 tests were significant and in long pump time, SGOT 2 was sensitive for knowing hepatic cell damage