Hypertonic solution decreases extravascular lung water in cardiac patients undergoing cardiopulmonary bypass surgery.

OBJECTIVE: To test the hypothesis that the infusion of hypertonic solution would decrease extravascular lung water postoperatively and thus improve pulmonary function. DESIGN: Prospective, randomized, blinded trial. SETTING: Tertiary cardiothoracic referral center. PARTICIPANTS: Twenty-six patients with coronary artery disease who underwent surgery with cardiopulmonary bypass (CPB). INTERVENTIONS: Patients were allocated randomly to receive 4 mL/kg of 7.2% NaCl/hydroxyethyl starch, 200/0.5 (HSH group) or an equal volume of 0.9% NaCl (control group) for 30 minutes starting after anesthesia induction. The extravascular lung water index, hemodynamic and biochemical data, and the rate of complications were analyzed. MEASUREMENTS AND MAIN RESULTS: The extravascular lung water index was significantly lower (7 v 9.5 mL/kg) in the HSH group at the first postoperative day (p < 0.01). The index of arterial oxygenation efficiency was significantly higher at 5 minutes and 2 and 4 hours after cardiopulmonary bypass (CPB) in the HSH group (p < 0.05). The alveolar-arterial oxygen tension difference was significantly lower at 5 minutes and 2 and 4 hours after CPB in the HSH group (p < 0.01). The cardiac index was significantly higher at 5 minutes after infusion in the HSH group (p < 0.05). CONCLUSIONS: The infusion of HSH leads to significant decreases in the extravascular lung water index during and after cardiac surgery and is associated with better preservation of pulmonary function and transient increases in the cardiac index. Further trials are needed to clarify the clinical advantages of hypertonic solution administration in patients undergoing surgery with CPB.

Oxidative stress and liver monooxygenase function after heart valve surgery.

BACKGROUND AND OBJECTIVES: this prospective study was carried out to evaluate oxidative stress and liver monooxygenase function after cardiac surgery in patients with acquired valvular heart disease. METHODS: 97 patients were studied. Oxidative stress was quantified with malondialdehyde, coupled trienes, hepatocuprein, and catalase activity. Liver monooxygenase function was evaluated with antipyrine pharmacokinetics. For statistical analyses, the Dunnett test and Pearson's correlation coefficient were used. RESULTS: on the 1st-2nd postoperative days, high lipid peroxidation activation (malondialdehyde: 9.6 ± 2.7 vs. 6.9 ± 2.0 nmol mL(-1), p <0.05) and a significant decrease in liver monooxygenase function (antipyrine clearance: 18.3 ± 11.1 vs. 39.0 ± 18.9 mL kg(-1)h(-1), p <0.05) were revealed. On the 3rd-4th and 11th-12th postoperative days, the intensity of oxidative stress decreased and monooxygenase function returned to baseline (antipyrine clearance: 45.6 ± 17.9 vs. 39.0 ± 18.9 mL kg(-1)h(-1)). The analysis showed a negative relationship between oxidative stress and liver monooxygenase function. CONCLUSION: patients undergoing surgery for acquired valvular heart disease have considerable oxidative stress and a decrease in liver monooxygenase function on the 1st-2nd postoperative days. Activation of lipid peroxidation is one of the main reasons for suppression of microsomal monooxygenases activity. A slowdown of liver microsomal oxidation might change the pharmacokinetic response of patients under drug therapy.