Effects of simvastatin on systemic inflammatory responses after cardiopulmonary bypass.

AIM: Cardiopulmonary bypass is associated with a complex systemic inflammatory response and the extent of their increase has been correlated with the development of postoperative complications. Recent studies suggest that treatment with statins is associated with a significant and marked decrease in inflammation-associated variables such as cytokines. Therefore, we investigated the effects of preoperative simvastatin treatment on systemic inflammatory response and perioperative morbidity after cardiopulmonary bypass. METHODS: A prospective, randomized study, was designed. Forty-four subjects undergoing elective coronary artery bypass grafting who fulfilled the inclusion criteria were randomized to treatment with simvastatin (20 mg/day, group A, N. 22) or control (group B, N. 22) before surgery. Plasma levels of interleukins (IL-6, IL-8, TNF-alpha), and systemic inflammatory response score (SIRS) were measured during the surgical intervention and over the following 48 postoperative hours. Cytokine levels were measured by enzyme-linked assays from plasma samples obtained at specific time points pre- and post-operation. RESULTS: In both groups the serum levels of the proinflammatory cytokines (IL-6, IL-8, TNF-alpha), and leukocytes, and the SIRS score increased significantly over the baseline, though no significant differences were observed between the two groups. The preoperative and postoperative course did not differ between both groups. CONCLUSIONS: In patients undergoing coronary artery bypass grafting with cardiopulmonary bypass, the administration of simvastatin doses not produce any changes in the inflammatory response as measured by the levels of IL-6, IL-8, TNF-alpha and SIRS score, nor does it reduce the complications after cardiac surgery.

[Central venous pressure, rewarming time, and total fluid replacement volume are predictors of mortality and complications after cardiac surgery]. / Presión venosa central, tiempo de recalentamiento y líquidos totales son factores postoperatorios de morbi-mortalidad en cirugía cardiaca.

OBJECTIVE: To analyze the influence of early (first day) postoperative factors on postoperative course in patients who have undergone heart surgery. PATIENTS AND METHODS: A cross-sectional study of consecutively enrolled heart surgery patients was designed. We recorded central venous pressure, time required for rewarming to a core temperature of 35.5degrees C, and total fluids administered in 24 hours. We then analyzed their influence on mortality and cardiac, pulmonary, and renal complications. RESULTS: Two hundred thirty-six patients were included. Central venous pressure over 18 mm Hg, time to rewarming over 6 hours, and administration of more than 5 L of fluids in the first 24 hours were factors associated with increased mortality and the development of cardiovascular, pulmonary, and renal complications. CONCLUSIONS: Central venous pressure, rewarming time, and fluid replacement volume required on the first day are predictors of postoperative course.

[Postoperative analgesia in cardiac surgery: spinal versus intravenous morphine]. / Analgesia postoperatoria en cirugía cardiaca: comparación de morfina intratecal versus morfina intravenosa.

OBJECTIVE: To compare the effects of spinal and intravenous administration of morphine to supplement anesthesia with remifentanil in terms of analgesia during early postoperative recovery and considering time until extubation. MATERIAL AND METHODS: This prospective, randomized, blinded trial enrolled 59 patients scheduled for cardiac surgery. The patients were assigned to receive either a spinal infusion of morphine (15 microg x Kg(-1)) or an intravenous infusion (0.3 mg x Kg(-1)). Anesthesia was maintained with 0.15 to 0.50 microg x Kg(-1) x min(-1) of remifentanil and 2 to 4 mg x Kg(-1) x h(-1) of propofol in perfusion. After the period of extracorporeal circulation, all patients were given an intravenous infusion of 30 mg of ketorolac. Later intravenous ketorolac was ministered at a dose of 30 mg per 8 hours; intravenous morphine (bolus dose of 3 mg) was also administered until pain was relieved. RESULTS: The same quality of postoperative analgesia and anesthetic recovery was achieved with both spinal and intravenous administration. The incidence of side effects was also similar. Likewise, the extubation times were similar in the 2 groups (spinal infusion group: 294.5 [SD, 150.5] minutes; intravenous group: 325.0 [139.9] minutes; P>0.05). Less postoperative intravenous morphine was administered in the first 24 hours to patients in the spinal morphine group (P<0.05) and fewer patients in that group required intravenous morphine boluses (P<0.05). CONCLUSIONS: Our study suggests that spinal morphine does not offer advantages over intravenous morphine with regard to postoperative analgesia, hemodynamic stability and respiratory parameters, time until extubation, or adverse effects.

[The effect of isoflurane on coronary autoregulation in hypothermia]. / Efecto del isoflurano sobre la autorregulación coronaria en hipotermia.

OBJECTIVES: To analyze the effect of isoflurane on myocardial metabolism and coronary hemodynamics during the reheating phase after heart surgery. PATIENTS AND METHODS: Sixteen patients (12 women and 4 men), with cardiac output greater than 0.5 undergoing aortic and/or mitral valve surgery, were studied prospectively. A retrograde thermodilution catheter was placed in the heart and a Swan-Ganz catheter was inserted in the pulmonary artery to determine coronary blood flow and pulmonary wedge pressure, respectively, as well as myocardial and systemic parameters. After surgery, and with hemodynamic variables stable and rectal temperature at 34 +/- 0.5 degrees C, 0.4% isoflurane was administered at the end of expiration. Variables were recorded before administering isoflurane and 20 minutes afterwards. RESULTS: Isoflurane administration decreased coronary perfusion pressure, coronary vascular resistance, regional myocardial oxygen consumption and myocardial oxygen output. Increases in coronary oxygen saturation and in large coronary vein saturation were also observed. No patient experienced significant changes in ST segment, enzymes or decreased clearance of lactic acid. CONCLUSIONS: Administering 0.4% isoflurane at the end of expiration effected coronary vasodilation without altering oxygenation or myocardial metabolism. Moreover, no electrocardiographic, enzymatic or metabolic signs of myocardial ischemia were observed.