Anesthesia and analgesia
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Anesthesia and analgesia · Aug 1985
Temperature and ventilation after hypothermic cardiopulmonary bypass.
Rewarming in the postoperative period after hypothermic cardiopulmonary bypass is often associated with hemodynamic and ventilatory instability. Temperature changes, PaCO2 values, and delivered mechanical ventilation were observed for the first 12 hr in the intensive care unit in 73 patients who had undergone cardiac surgery with hypothermic cardiopulmonary bypass. ⋯ During rewarming, the most common abnormality of PaCO2 on mechanical ventilation was acute respiratory acidosis (PaCO2 greater than 45 mm Hg, pH less than 7.35), which occurred in 42% of patients. This suggests that ventilatory management in the early postoperative period after hypothermic cardiopulmonary bypass should be carefully adjusted to the increased metabolic rate during rapid rewarming.
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Anesthesia and analgesia · Aug 1985
Randomized Controlled Trial Clinical TrialEpidural morphine: a clinical double-blind study of dosage.
The purpose of this randomized double-blind study was to determine the optimal dose of epidural morphine by establishing a dose-effect relationship. The 139 patients, who had orthopedic operations on the lower extremities, received continuous lumbar epidural anesthesia with bupivacaine, 0.75%, with or without the addition of 1, 2, 3, 4, or 5 mg of morphine hydrochloride. Analgesia and side effects were determined during the first 24 hr postoperatively. ⋯ Frequency of catheterization and pruritus increased dose-dependently. The mean PaCO2 after 5 mg of epidural morphine averaged 5 mm Hg higher than in the control group, indicating minor respiratory depression, better analgesia, or both. The dose of 3 mg of epidural morphine added to the local anesthetic is recommended for postoperative analgesia after surgery of the lower extremity; it is a compromise that provides adequate analgesia with an acceptably low frequency and intensity of side effects.
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Anesthesia and analgesia · Aug 1985
Clinical Trial Controlled Clinical TrialEffects of colloid or crystalloid administration on pulmonary extravascular water in the postoperative period after coronary artery bypass grafting.
The effect of postoperative fluid management on pulmonary extravascular thermal volume (ETVL) as in index of pulmonary extravascular water after coronary artery bypass grafting was compared, using the thermal-dye technique, among five patients who received 5% albumin (group A), five patients who received 6% hydroxyethyl starch (group H), and five who received lactated Ringer's solution (group C). Intraoperatively, all patients received lactated Ringer's solution intravenously, and the cardiopulmonary bypass (CPB) circuit prime included 5% albumin. No statistically significant changes in ETVL occurred postoperatively in any group, nor did ETVL differ significantly between groups. ⋯ PaO2 decreased significantly, and alveolar-arterial oxygen partial pressure difference increased significantly in all groups on AM1. In Group H, Qsp/Qt returned to levels observed before CPB by AM1 (0.27 +/- 0.09). We conclude that in patients without postoperative increases in WP, ETVL changes minimally during CPB and is not influenced by the type of fluid administered as the primary volume replacement in the postoperative period.
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Anesthesia and analgesia · Aug 1985
Comparative StudyRegional blood flows during induced hypotension produced by nitroprusside or trimethaphan in the rhesus monkey.
In monkeys anesthetized with 70% nitrous oxide and 0.5% inspired halothane in oxygen, we measured changes in systemic hemodynamics and regional blood flows produced by nitroprusside and trimethaphan. Regional blood flow measurements were made using the radioactive microsphere technique. Control measurements were made before infusion of nitroprusside and trimethaphan into each animal in sequence in amounts adequate to reduce mean arterial pressure to approximately 55 +/- 5 mm Hg. ⋯ Neither drug produced changes in renal or total hepatic blood flows. We conclude that brain oxygen reserve is decreased during hypotension induced by trimethaphan. Blood flows to other organs are not significantly impaired in monkeys during hypotension to a mean arterial pressure of approximately 55 mm Hg induced by either nitroprusside or trimethaphan.