Anesthesia and analgesia
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Anesthesia and analgesia · Nov 1995
Randomized Controlled Trial Clinical TrialEpidural ropivacaine infusion for postoperative analgesia after major lower abdominal surgery--a dose finding study.
Ropivacaine exhibits less cardiotoxicity and causes less motor block than bupivacaine when used in equianalgesic doses. This makes ropivacaine potentially well suited for epidural infusion for postoperative analgesia. The aim of this study was to determine which of three concentrations of epidurally administered ropivacaine infused for postoperative analgesia would attenuate intravenous opioid analgesia requirements while also minimizing motor block. ⋯ Total PCA morphine use was more over the 21-h period in Group S than all the ropivacaine groups, being significantly so for Group 2 (median values: Group S, 43.3 mg; Group 1, 18.7 mg; Group 2, 7.5 mg; Group 3, 19 mg; for Group 2, P = 0.03). Visual analog scale (VAS) scores on coughing were significantly lower (i.e., less pain) than control for all ropivacaine groups after 4 h of infusion and also for Groups 2 and 3 after 8 h of infusion. (Median VAS (mm) on coughing at 8 h: Group S = 70, Group 1 = 56, Group 2 = 32, Group 3 = 0; for Groups 2 and 3, P < 0.05 compared to Group S). There was a dose-related increase in the amount of motor block, with Group 3 having significantly more motor block than all other groups at 4 and 8 h.(ABSTRACT TRUNCATED AT 250 WORDS)
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Anesthesia and analgesia · Nov 1995
Randomized Controlled Trial Clinical TrialThe effects of anesthetic technique on the hemodynamic response and recovery profile in coronary revascularization patients.
This study was undertaken to assess the effects of propofol (versus enflurane, fentanyl, and thiopental) on hemodynamic stability and recovery characteristics when used for maintenance of anesthesia during elective coronary artery bypass grafting (CABG) procedures. Ninety premedicated patients scheduled for elective coronary revascularization had anesthesia induced with fentanyl 25 micrograms/kg intravenously (i.v.). When the mean arterial blood pressure (MAP) increased 10% above preoperative baseline values, patients were randomized to receive one of four anesthetic treatments: enflurane, 0.25-2.0%; fentanyl, 10-20 micrograms/kg i.v. bolus doses; propofol, 50-250 micrograms.kg-1.min-1 i.v.; or thiopental, 100-750 micrograms.kg-1.min-1 i.v.. ⋯ During CPB, fentanyl-treated patients required vasoconstrictors more often than patients in the other three treatment groups (14/22 vs 6/24, 4/23, and 5/21 in the enflurane, propofol, and thiopental groups, respectively) (P < 0.01). Although fentanyl-treated patients had significantly greater requirements for inotropic support during weaning from CPB than propofol-treated patients (14/22 vs 7/23) (P < 0.038), there were no significant differences among the groups in the postbypass or ICU periods. Propofol-treated patients responded to verbal stimuli (2.1 +/- 1.3h vs 4.0 +/- 3.5h, 4.7 +/- 2.7h, and 5.6 +/- 3.6h in the enflurane, fentanyl, and thiopental groups, respectively) (P = 0.01) and followed commands earlier (propofol 7.3 +/- 5.2h vs enflurane 12.5 +/- 5.7h, fentanyl 13.1 +/- 6.6h, and thiopental 12.8 +/- 6.7 h) (P = 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)
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Anesthesia and analgesia · Nov 1995
Randomized Controlled Trial Clinical TrialEfficacy of simulated epidural test doses in adult patients anesthetized with isoflurane: a dose-response study.
A recent study demonstrated that an epidural test dose containing 15 micrograms epinephrine was an imperfect marker for intravascular injection during isoflurane anesthesia based on the conventional heart rate (HR) criterion (positive if > or = 20 bpm increase). We have determined the effects of epinephrine doses and isoflurane concentrations on these efficacies in healthy adult patients during isoflurane anesthesia. Eighty patients were randomly assigned to one of four groups according to the simulated test dose injected intravenously (IV) under 1% end-tidal isoflurane and nitrous oxide after endotracheal intubation. ⋯ Although none in the saline group developed a HR increase > or = 20 bpm, 2, 14, and 12 patients elicited positive responses in the epinephrine 7.5, 15, and 22.5 groups (10%, 70%, and 60% sensitivities), respectively. If a positive HR response was defined by an increase of 10 bpm, sensitivities were 55%, 100%, and 100% in the epinephrine 7.5, 15, and 22.5 groups, respectively. On the other hand, none in the saline group, 12 in the epinephrine 7.5 group, and all patients in the epinephrine 15 and 22.5 groups developed maximum SBP increases > or = 15 mm Hg.(ABSTRACT TRUNCATED AT 250 WORDS)
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Anesthesia and analgesia · Nov 1995
Randomized Controlled Trial Clinical TrialIntraperitoneal application of bupivacaine during laparoscopic cholecystectomy--risk or benefit?
We investigated, in a double-blind study, the effects of intraperitoneal local anesthetics during laparoscopic cholecystectomy. In Part A of the study 30 patients received 50 mL saline 0.9% (A 0), bupivacaine 0.125% (A 125), or bupivacaine 0.25% (A 25) intraperitoneally at the end of surgery. Mean maximum plasma concentrations of bupivacaine reached 0.48 mg/L (range 0.15-0.90 mg/L) in Group A 125 and 1.0 mg/L (0.35-2.10 mg/L) in Group A 25 within 15 min (range, 5-30 min). ⋯ In Part B, 24 patients received placebo (B 0) or bupivacaine 0.25% (B 25). Postoperative hypoxemic periods (oxygen saturation < 92%) were significantly more frequent in Group B 25. Considering the questionable benefits and the potential risks, we would not recommend the application of intraperitoneal bupivacaine during laparoscopic cholecystectomy.
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Anesthesia and analgesia · Nov 1995
Aprotinin prolongs whole blood activated partial thromboplastin time but not whole blood prothrombin time in patients undergoing cardiac surgery.
Aprotinin is being used increasingly to limit cardiopulmonary bypass (CPB)-induced coagulation derangements. Since whole blood prothrombin time (PT) and activated partial thromboplastin time (APTT) assays are beneficial in the treatment of bleeding after CPB, we studied the potential effect of aprotinin on these whole blood assays. Blood specimens from 151 cardiac surgical patients were obtained in two phases: prior to heparin administration, before CPB, and subsequent to heparin neutralization after CPB. ⋯ Whole blood PT results were similar between normal saline. (NS)- and aprotinin-spiked specimens before CPB (A, 12.9 +/- 1.5s; NS, 12.8 +/- 1.5s; P = 0.76) and after CPB (A, 17.5 +/- 2.4s; NS, 17.7 +/- 2.4s; P = 0.58). In contrast, whole blood APTT results were prolonged in aprotinin-spiked specimens prior to CPB (A, 63.3 +/- 32.2s; NS, 38.6 +/- 16.3s; P < 0.0001) and after CPB (A, 65.9 +/- 23.7s; NS, 45.7 +/- 14.4s; P < 0.0001). A dose-dependent prolongation of whole blood APTT by aprotinin was demonstrated by a greater mean difference in APTT (P = 0.0001) between specimens spiked with NS or 200 KIU (17.5 +/- 12.2s) vs 400 KIU (27.8 +/- 21.5s) of aprotinin.(ABSTRACT TRUNCATED AT 250 WORDS)