Anesthesia and analgesia
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The aim of this study was to determine the need for supplemental oxygen during recovery from general anesthesia for ambulatory surgery in healthy women without obesity or respiratory disease. Arterial oxygen saturation by pulse oximetry (SpO2) was monitored throughout the first postoperative hour in 164 patients. The patients breathed room air during recovery. ⋯ The need for supplemental oxygen increased with increasing age (P less than 0.05) but was not associated with a history of cigarette smoking, tracheal intubation, amount of opioids or sedatives given intraoperatively, anesthetic duration, or level of consciousness during recovery. Hypoxemia was neither predictable nor clinically apparent. We recommend that, unless arterial oxygenation is monitored, ambulatory patients should routinely receive supplemental oxygen during recovery from general anesthesia.
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Anesthesia and analgesia · Oct 1988
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%). ⋯ 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)
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Anesthesia and analgesia · Sep 1988
Epidural blood flow and regression of sensory analgesia during continuous postoperative epidural infusion of bupivacaine.
Epidural blood flow was measured in seven patients undergoing elective abdominal surgery during combined lumbar epidural and general anesthesia. After an initial dose of 20 ml plain bupivacaine 0.5%, a continuous epidural infusion of bupivacaine 0.5% (8 ml/hr) was given for 16 hours for postoperative pain relief. The epidural blood flow was measured by a local 133Xe clearance technique in which 15-35 MBq 133Xe diluted in 1 ml saline was injected through the epidural catheter on the day before surgery (no bupivacaine), 30 minutes after the initial dose of bupivacaine on the morning before surgery, and 8, 12, and 16 hours later during the continuous infusion. ⋯ In these two patients epidural blood flow remained constant after the initial increase. Flow increased further to 10.3 +/- 0.8 ml/min per 100 g tissue (P less than 0.03) in the other five patients as the level of sensory analgesia regressed postoperatively. These data suggest that changes in epidural blood flow during continuous epidural infusion of bupivacaine, and thus changes in rates of vascular absorption of bupivacaine from the epidural space, may be an important factor contributing to differences in rates of regression of sensory analgesia.