Anesthesia and analgesia
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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.
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Anesthesia and analgesia · Aug 1985
Decreased sensitivity to metocurine in patients with upper motoneuron disease.
Responses to the nondepolarizing muscle relaxant, metocurine, were studied in eight hemiplegic and eight unmatched patients with normal motor strength during the general anesthetic given for various neurosurgical operations. Metocurine, 0.3 mg/kg, was administered intravenously, and indirectly evoked thumb twitch tensions were measured on both sides in the hemiplegic patients, and on one side in the normal patients. Arterial blood samples were obtained as twitch tension was recovering, and serum metocurine concentrations were determined using a specific radioimmunoassay. ⋯ We were, however, unable to detect any significant deviation from parallelism among the three regression lines. We also measured time to 50% return of single twitch height for each data group as follows (mean +/- SEM: for NMS patients, 242 +/- 73 min; for the unaffected arm of hemiplegic patients, 116 +/- 60 min; and for the affected arm of hemiplegic patients, 59 +/- 36 min. By ANOVA and the Bonferroni test, each value was different from the other at P less than or equal to 0.01.(ABSTRACT TRUNCATED AT 250 WORDS)
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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
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.