Anesthesia and analgesia
-
Anesthesia and analgesia · Sep 1993
Randomized Controlled Trial Comparative Study Clinical TrialSerial intravenous doses of dezocine, morphine, and nalbuphine in the management of postoperative pain for outpatients.
Adult patients who had arthroscopic surgery under general anesthesia and requested postoperative pain relief were randomized to receive treatment in a double-blind protocol with 5 mg of intravenous dezocine (20 patients), morphine (22 patients), nalbuphine (18 patients), or saline (24 patients). At 10-min intervals, starting with the first dose of analgesic, patients could choose up to three additional doses of the primary treatment, or choose an alternative analgesic if the primary drug was unsatisfactory. One to four doses of morphine were given as the alternate treatment if the initial treatment was dezocine or nalbuphine, and one to four doses of dezocine were given if the initial treatment was saline or morphine. ⋯ As an alternate analgesic in this study, dezocine required fewer doses to achieve patient satisfaction and was thus more efficacious than morphine. The incidence of treatment-related, adverse effects was different from that of saline or other treatments only for nalbuphine-related pain or burning on injection and dezocine-related facial itching. With respect to analgesic actions and side effects, dezocine seems more like morphine than nalbuphine.
-
Anesthesia and analgesia · Sep 1993
Comparative StudyRocuronium onset of action: a comparison with atracurium and vecuronium.
The onset, maximal neuromuscular block, and duration of rocuronium were compared with atracurium and vecuronium during enflurane anesthesia. Sixty patients received rocuronium (80, 100, 120, or 160 micrograms/kg). Enflurane enhanced a rocuronium neuromuscular block in a dose-related manner; the ED50 was 104 +/- 11 and 83 +/- 7 micrograms/kg (SEM) during 1% and 2% enflurane anesthesia, respectively. ⋯ Time to 90% of final block was 1.35 min for rocuronium, 3.06 min for atracurium, and 3.71 min for vecuronium. Using these equipotent doses, atracurium also had a shorter time to develop neuromuscular block than vecuronium (P < 0.05). For these three intermediate duration neuromuscular blockers, speed of onset was inversely related to their potency, confirming a relationship that had been demonstrated for the long-acting drugs pancuronium, d-tubocuranine, and gallamine.
-
Anesthesia and analgesia · Sep 1993
Randomized Controlled Trial Comparative Study Clinical TrialMuscle paralysis by rocuronium during halothane, enflurane, isoflurane, and total intravenous anesthesia.
We determined the dose-response relationship, the onset time, the duration, and the recovery time of a rocuronium neuromuscular block under four anesthesia techniques. Patients were equally randomized to four different groups (n = 20) receiving 0.5%-1% halothane, 1.5%-2% enflurane, 1.2%-1.8% isoflurane end-tidal concentration in 34%/66% O2/N2O, or 6.0 mg.kg-1 x h-1 propofol without N2O for anesthesia and alfentanil for analgesia. Strength of thumb adduction in response to single and train-of-four stimulation of the ulnar nerve was quantitated. ⋯ There was a statistically significant difference between the halothane and TIVA, and between the enflurane and TIVA groups (P < 0.05). Rocuronium has a short onset time and an intermediate duration of action. The neuromuscular blocking potency and pharmacodynamic profile are moderately influenced by volatile anesthetics.
-
Anesthesia and analgesia · Sep 1993
Selecting ventilator settings according to variables derived from the quasi-static pressure/volume relationship in patients with acute lung injury.
Knowledge of the pressure/volume (P/V) relationship of the lung may allow selection of tidal volume and positive end-expiratory pressure (PEEP) to optimize gas exchange without adversely affecting lung function or hemodynamics. Ten patients with acute lung injury were stabilized on controlled mechanical ventilation, based on conventional practice, using criteria from arterial blood gas data. The P/V relationship was determined under quasi-static conditions (end-expiratory and end-inspiratory, no flow periods > 0.8 s) during mechanical ventilation with an automated procedure that changed PEEP in a stepwise fashion. ⋯ Intrapulmonary shunt decreased from 0.28 +/- 0.08 (baseline) to 0.14 +/- 0.05 (12 h) (P < 0.001). Hemodynamic variables did not change. Our data suggest that using variables derived from a quasi-static P/V loop during mechanical ventilation under muscle paralysis is clinically superior compared to blood gas criteria for titration of ventilator settings.
-
Anesthesia and analgesia · Sep 1993
Randomized Controlled Trial Comparative Study Clinical TrialA clinical and laboratory study to compare the addition of 0.2 mg of morphine, 0.2 mg of epinephrine, or their combination to hyperbaric bupivacaine for spinal anesthesia in cesarean section.
The aim of this prospective, randomized, double-blind study was to compare the effects of adding either preservative-free morphine, 0.2 mg (n = 20), epinephrine, 0.2 mg (n = 21), or a combination of both (n = 29) to hyperbaric bupivacaine in parturients having elective cesarean sections during spinal anesthesia. Ten additional patients receiving spinal bupivacaine alone were studied as the Control Group. High-pressure liquid chromatography with a sensitivity of 20 micrograms/mL was used to measure serum bupivacaine in all subjects. ⋯ The concentrations of bupivacaine in umbilical arterial and venous sera were less than the sensitivity level of the analytical method. We conclude that the addition of 0.2 mg of morphine plus 0.2 mg of epinephrine to hyperbaric bupivacaine improves the intra- and postoperative analgesia without an added risk. This improvement is not due to vasoconstriction and a reduction in the absorption of bupivacaine from the subarachnoid space.