Left ventricular performance during propofol or methohexital anesthesia: isotopic and invasive cardiac monitoring.

Using gated radionuclide ventriculography and invasive cardiac monitoring, the effects of propofol and methohexital on left ventricular volumes and function were investigated in 22 unpremedicated patients (ASA physical status III, 50-78 yr) with chronic coronary artery disease (NYHA class II-III). Anesthesia was induced with either propofol or methohexital (2 mg/kg), followed by a maintenance infusion of 100 micrograms.kg-1.min-1. Vecuronium (0.05 mg/kg) was administered and ventilation (FIO2, 1.0) was manually controlled (FECO2, 0.04-0.05). Data acquisitions were serially obtained over 15 min. Propofol and methohexital anesthesia caused an average 15% decrease in mean arterial pressure, associated with a 20% decrease in cardiac index without a decrease in systemic vascular resistance index. It is interesting that the determinants of these hemodynamic effects were different. Heart rate did not change during propofol infusion despite the decrease in mean arterial pressure, whereas heart rate increased during methohexital infusion. In the propofol group, the decrease in cardiac index was associated with decreases in indicators of preload (end-diastolic volume and pulmonary capillary wedge pressure), whereas end-systolic volume and global ejection fraction did not change statistically. In the methohexital group, the decrease in cardiac index was associated with a decrease in global ejection fraction and an increase in end-systolic volume, whereas indicators of preload remained unchanged. It is concluded that methohexital reduces left ventricular performance. In contrast, propofol preserves left ventricular performance despite a likely negative inotropic effect.

Left ventricular function during propofol and fentanyl anesthesia in patients with coronary artery disease: assessment with a radionuclide approach.

Using gated radionuclide ventriculography and invasive cardiac monitoring, the effects of propofol alone and in combination with fentanyl on left ventricular (LV) volumes and function were investigated in 10 ASA III, unpremedicated patients (51-75 years) with coronary artery disease (NYHA II-III). Anesthesia was induced with propofol (2 mg/kg) followed by an infusion (100 micrograms.kg-1.min-1). Vecuronium (0.05 mg/kg) was administered and ventilation (FIO2, 1.0) was manually controlled via a face mask (FECO2, 4-5%). Data acquisitions were serially obtained over 15 minutes after the bolus IV injection of propofol and 5 minutes after the injection of fentanyl (5 micrograms/kg). Propofol induced a rapid decrease (15%) in mean arterial pressure (MAP) exclusively related to a decrease in cardiac index (CI), without reduction in indexed systemic vascular resistances (SVRI). Despite the decrease in MAP, heart rate did not change. The decrease in CI was associated with a lower preload. After the addition of fentanyl, MAP decreased significantly (35%) below the last set of propofol measurements. The decrease in MAP was associated with a reduction in CI and SVRI. Fentanyl was also associated with a significant decrease in heart rate (16%) resulting in a decrease in CI, whereas stroke index and end diastolic volume did not change. Neither global ejection fraction (EF) nor end systolic volume changed significantly at any time, nor were there changes in the ECG or in regional ejection fractions (REF). The absence of changes in REF was consistent with lack of wall motion abnormalities of the left ventricle. Propofol alone and in combination with fentanyl does not alter LV performance in patients with good LV function.(ABSTRACT TRUNCATED AT 250 WORDS)

[Spinal anesthesia with bupivacaine in lower urologic surgery. Our experience apropos of 500 cases]. / La rachianesthésie à la bupivacaäine en chirurgie urologique basse. Notre expérience à propos de 500 cas.

Rachianesthesia was used for 500 lower urinary tract operations, including 50 repeat procedures, the anesthetic employed being bupivacaine. Patients were frequently hypertensive and presented cardiopathies, usually ischemic in origin. The surgical procedure generally involved transurethral prostate resection for adenoma or carcinoma, or endoscopic resection of a bladder tumor, and all patients received preventive heparin therapy using Kakkar's method. Induction of anesthesia occurs between 30 seconds and one minute after completing the injection a procedure lasting 2 to 5 minutes. Full anesthesia is obtained after 2 to 3 minutes, and is maintained during the mean operation period of 69 +/- 32 minutes by regular intraspinal injections of anesthetic. Results were perfect in 425 cases, 48 patients required additional sedatives, 23 a potent analgesic and 4 a general anesthetic after an operating time extending beyond 100 minutes heart rate remained fairly regular while diminishing slightly in frequency (an average of 4 beats/min). The fall in blood pressure was globally moderate (296 patients) and was unaltered in 204 cases. Hemodynamic modifications lasted for 3 à 4 minutes only and were corrected by appropriate therapy. Postoperative complications were mainly of the headache type (26 cases: 5%), but three patients developed angina from a coronary ischemic accident. Myocardial infarction was not observed, and no particularly incidents were reported in the 32 patients requiring repeat rachianesthesia. The simple execution and efficacy of this mode of anesthesia is emphasized, an additional need for general anesthesia being a rare event. The compound is well tolerated, hemodynamic modifications are moderate and neurological sequelae lacking. Rachianesthesia with bupivacaine appears to be among the methods of choice for lower urinary tract surgery.