Alina M. Grigore

The rewarming rate and increased peak temperature alter neurocognitive outcome after cardiac Surgery

UNLABELLED Neurocognitive dysfunction is a common complication after cardiac surgery. We evaluated in this prospective study the effect of rewarming rate on neurocognitive outcome after hypothermic cardiopulmonary bypass (CPB). After IRB approval and informed consent, 165 coronary artery bypass graft surgery patients were studied. Patients received similar surgical and anesthetic management until rewarming from hypothermic (28 degrees -32 degrees C) CPB. Group 1 (control; n = 100) was warmed in a conventional manner (4 degrees -6 degrees C gradient between nasopharyngeal and CPB perfusate temperature) whereas Group 2 (slow rewarm; n = 65) was warmed at a slower rate, maintaining no more than 2 degrees C difference between nasopharyngeal and CPB perfusate temperature. Neurocognitive function was assessed at baseline and 6 wk after coronary artery bypass graft surgery. Univariable analysis revealed no significant differences between the Control and Slow Rewarming groups in the stroke rate. Multivariable linear regression analysis, examining treatment group, diabetes, baseline cognitive function, and cross-clamp time revealed a significant association between change in cognitive function and rate of rewarming (P = 0.05). IMPLICATIONS Slower rewarming during cardiopulmonary bypass (CPB) was associated with better cognitive performance at 6 wk. These results suggest that a slower rewarming rate with lower peak temperatures during CPB may be an important factor in the prevention of neurocognitive decline after hypothermic CPB.

Prospective Randomized Trial of Normothermic versus Hypothermic Cardiopulmonary Bypass on Cognitive Function after Coronary Artery Bypass Graft Surgery

Background Despite significant advances in cardiopulmonary bypass (CPB) technology, surgical techniques, and anesthetic management, central nervous system complications occur in a large percentage of patients undergoing surgery requiring CPB. Many centers are switching to normothermic CPB because of shorter CPB and operating room times and improved myocardial protection. The authors hypothesized that, compared with normothermia, hypothermic CPB would result in superior neurologic and neurocognitive function after coronary artery bypass graft surgery. Methods Three hundred patients undergoing elective coronary artery bypass graft surgery were prospectively enrolled and randomly assigned to either normothermic (35.5–36.5°C) or hypothermic (28–30°C) CPB. A battery of neurocognitive tests was performed preoperatively and at 6 weeks after surgery. Four distinct cognitive domains were identified and standardized using factor analysis and were then compared on a continuous scale. Results Two hundred twenty-seven patients participated in 6-week follow-up testing. There were no differences in neurologic or neurocognitive outcomes between normothermic and hypothermic groups in multivariable models, adjusting for covariable effects of baseline cognitive function, age, and years of education, as well as interaction of these with temperature treatment. Conclusions Hypothermic CPB does not provide additional central nervous system protection in adult cardiac surgical patients who were maintained at either 30 or 35°C during CPB.

Clevidipine effectively and rapidly controls blood pressure preoperatively in cardiac surgery patients: the results of the randomized, placebo-controlled efficacy study of clevidipine assessing its preoperative antihypertensive effect in cardiac surgery-1.

BACKGROUND:Clevidipine is an ultrashort-acting, third-generation IV dihydropyridine calcium channel blocker that exerts rapid and titratable arterial blood pressure reduction, with fast termination of effect due to metabolism by blood and tissue esterases. As an arterial-selective vasodilator, clevidipine reduces peripheral vascular resistance directly, without dilating the venous capacitance bed. In this randomized, double-blind, placebo-controlled multicenter trial we evaluated the efficacy and tolerability of clevidipine in treating preoperative hypertension. METHODS:One-hundred-fifty-two patients scheduled for cardiac surgery with current or recent hypertension were randomized to receive clevidipine or placebo preoperatively. One-hundred-five patients met postrandomization entrance criteria (systolic blood pressure [SBP] ≥160 mm Hg after inserting an arterial catheter) for reduction by ≥15% from baseline in SBP. The patients thus received infusions of clevidipine (0.4–8.0 &mgr;g · kg−1 · min−1) or 20% lipid emulsion (placebo) for at least 30 min. Treatment failure was defined as failure to reduce SBP by ≥15% from baseline or discontinuance of drug for any reason. RESULTS:Patients treated with clevidipine demonstrated a 92.5% rate of treatment success and a significantly lower rate of treatment failure (7.5%, 4 of 53) than patients receiving placebo (82.7%, 43 of 52; P < 0.0001). Clevidipine achieved target blood pressures (SBP reduced by ≥15%) at a median of 6.0 min (95% confidence interval 6–8 min). A modest increase in heart rate from baseline occurred during clevidipine administration. Adverse events for each treatment group were similar. CONCLUSIONS:Clevidipine was effective in rapidly decreasing blood pressure preoperatively to targeted blood pressure levels and was well tolerated in patients scheduled for cardiac surgery.