Anesthesia and analgesia
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Anesthesia and analgesia · Oct 1993
Randomized Controlled Trial Comparative Study Clinical TrialA comparative study of analgesia after knee surgery with intraarticular bupivacaine, intraarticular morphine, and lumbar plexus block.
Following arthroscopic surgery of the knee, 60 ASA I-II patients were randomly allocated to three different groups (n = 20 each) in an attempt to establish the best postoperative analgesic protocol: 20 ml of bupivacaine (0.25%; 50 mg) intra-articularly (IA) (Group 1); continuous three-in-one lumbar plexus block using a catheter to administer 0.25 ml/kg of bupivacaine (0.25%; single-shot) plus continuous pump infusion of the same drug (0.03 ml.kg-1 x h-1 of 0.25% bupivacaine for 24 h) (Group 2); or 1 mg of morphine with 20 ml of saline IA (Group 3). The results were appraised in a double-blind manner, and the degree of postoperative pain was evaluated by visual analog scale (VAS) at constant hourly intervals for the first 24 h, by the incidence of secondary effects, and by the need for complementary analgesia. Group 2 (three-in-one) VAS values were lower 16 and 24 h after surgery and also globally (P < 0.05), with respect to the other two groups. ⋯ No other secondary effects were observed. We conclude that all three analgesic methods proved efficient, as reflected by the scant requirements for additional analgesics and the degree of expressed patient satisfaction. However, lumbar plexus block (three-in-one) with continuous bupivacaine infusion was most effective, and, although it constitutes an added technique, its scant complications and easy performance make its use advisable.
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Anesthesia and analgesia · Oct 1993
Multicenter Study Clinical TrialAdverse events in a multicenter phase IV study of propofol: evaluation by anesthesiologists and postanesthesia care unit nurses.
Phase II and III studies are tightly controlled trials investigating adverse effects before government approval of a new drug. However, because postapproval Phase IV studies involve a much larger and more complex population, the true nature of adverse effects can be seen. We analyzed Phase IV data for the new drug propofol with regard to the incidence of adverse events, and evaluations of such events by anesthesiologists versus postanesthesia care unit (PACU) nurses. ⋯ The PACU nurse was more influenced by nausea, vomiting, or postoperative pain; and the anesthesiologist was more influenced by postoperative confusion or delayed emergence from anesthesia. For only 0.6% of patients did both evaluators rate recovery as poor. Anesthesiologists gave more weight to intraoperative adverse events, and nurses to postoperative events.(ABSTRACT TRUNCATED AT 250 WORDS)
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Anesthesia and analgesia · Oct 1993
Clinical pharmacology of mivacurium in pediatric patients less than off years old during nitrous oxide-halothane anesthesia.
We determined the dose-response relationship of mivacurium in infants 2-6 and 7-11 mo of age during nitrous oxide-halothane anesthesia. The neuromuscular and cardiovascular effects of a bolus dose of mivacurium larger than the ED95 in infants and young children from 2-23 mo of age were observed. The infusion rate of mivacurium required to maintain approximately 95% neuromuscular block was determined. ⋯ The time to onset of maximum block was 1.6 +/- 0.3 (0.7-2.7) (mean, SEM [range]) min, and time to recovery to 25% of T1 (T25) was 7.5 +/- 0.7 (5.5-11) min after 150 micrograms/kg in these patients. A bolus dose of 200 micrograms/kg mivacurium in infants and young children (7-23 mo) produced 100% depression of T1 in 14 of 17 patients, 97% depression in 2, and 90% depression in 1. The time to onset of maximum block was 1.5 +/- 0.1 (0.8-3) min and T25 was 10.3 +/- 1.5 (4.8-30.5) min after 200 micrograms/kg in these patients.(ABSTRACT TRUNCATED AT 250 WORDS)
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Anesthesia and analgesia · Oct 1993
Predictive accuracy of continuous alfentanil infusion in volunteers: variability of different pharmacokinetic sets.
To evaluate the variability of the predictive accuracy of alfentanil by using different pharmacokinetic data sets, eight healthy young male adult volunteers were given the same alfentanil infusion for 4 h. Nineteen venous blood samples were taken from each volunteer, and alfentanil concentrations were titrated by radioimmunoassay. For each volunteer, the pharmacokinetic variables of a two-compartment model were calculated, averaged, and considered as a reference set. ⋯ The reference set had the best predictive accuracy (MDAPE, 23.6%). Five sets from the literature also showed a reliable predictive accuracy but four other sets with a clearance more than 5 mL.kg-1.min-1 and derived from a large bolus injection were inaccurate (MDAPE > 50%) as they underestimated the alfentanil concentrations. We conclude that pharmacokinetic sets derived from large bolus should not be selected to accurately predict alfentanil infusion.
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Anesthesia and analgesia · Oct 1993
Multicenter Study Clinical TrialHemodynamic effects of propofol: data from over 25,000 patients.
To investigate clinically important hypotension and bradycardia after induction of anesthesia with propofol, we analyzed data from a Phase IV stepwise study involving 25,981 patients, 1722 institutions, and 1819 anesthesiologists. In Step 1, propofol was used for induction only. In Step 2, propofol was used for induction and then maintenance by intermittent injection. ⋯ Giving this new drug by protocol, even inexperienced anesthesiologists incurred few adverse hemodynamic changes. Hemodynamic changes were transient and rarely (< 0.2%) required drug therapy. Cardiovascular changes and drug interactions were predictable and manageable based on knowledge of the pharmacology of propofol.