Effects of small doses of prostaglandin E(1) on systemic hemodynamics and jugular venous oxygen saturation during cardiopulmonary bypass

STUDY OBJECTIVE: To examine the effects of small doses of prostaglandin E(1) (PGE(1)) on systemic hemodynamics and cerebral oxygenation during cardiopulmonary bypass(CPB). DESIGN: Randomized, prospective study. SETTING: Cardiac surgery at Saitama Cardiovascular and Pulmonary Center. PATIENTS: Forty patients who underwent elective coronary artery bypass surgery. INTERVENTIONS: The study was performed at the stable CPB period. Patients were randomly divided into four groups: control group (n = 10) received an infusion of saline, PGE(1) 10 group (n = 10) received an infusion of PGE(1) 10 ng/kg/min, PGE(1) 25 group (n = 10) received an infusion of PGE(1) 25 ng/kg/min, and the PGE(1) 50 group (n = 10) received an infusion of PGE(1) 50 ng/kg/min. MEASUREMENTS: After measuring the baseline partial pressure of the arterial oxygen saturation (SpO(2)), mixed venous oxygen saturation (SvO(2)), and jugular venous oxygen saturation (SjvO(2)), blood gases, and cardiovascular hemodynamic values, PGE(1) was infused intravenously at rate of between 10 and 50 ng/kg/min. PGE(1) infusion continued 30 minutes after the start of drug infusion, and the blood gas analysis and cardiovascular hemodynamic values were simultaneously determined together with the hemodynamic values at 2, 5, 10, 20, and 30 minutes during drug infusion. At 30 minutes after discontinuation of the drug infusion, the blood gas analyses were simultaneously determined together with the hemodynamic values. MAIN RESULTS: Mean arterial pressure (MAP) in PGE(1) 25 and 50 groups was decreased 20 and 30 minutes after the start of PGE(1) infusion compared with the baseline value (p < 0.05). In contrast, SvOm(2) in PGE(1) 25 and 50 groups was increased 20 and 30 minutes after the start of PGE(1) infusion compared with the baseline value (p < 0.05). There was no change in SjO(2) value despite a decrease in MAP during the study. CONCLUSIONS: Cerebral oxygenation estimated by SjvO(2) was maintained despite a decrease in MAP during the administration rate of PGE(1) between 10 and 50 ng/kg/min.