Anesthesia and analgesia
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Anesthesia and analgesia · May 2001
Randomized Controlled Trial Clinical TrialDuration of action of vecuronium after an intubating dose of rapacuronium, vecuronium, or succinylcholine.
Rapacuronium (RAP) is a new, rapid-onset, short-duration, nondepolarizing neuromuscular blocker. If RAP is used to facilitate endotracheal intubation, what will the duration of a subsequent maintenance dose of vecuronium (VEC) be? We investigated the duration of action of a maintenance dose of VEC after intubation with RAP, VEC, or succinylcholine (SUC). Adult surgical patients under general anesthesia were randomly allocated to receive a tracheal intubating dose of RAP 1.5 mg/kg, VEC 0.1 mg/kg, or SUC 1 mg/kg. The anesthetic was induced with propofol and maintained with propofol, nitrous oxide, and oxygen. Neuromuscular function was monitored with electromyography. Recovery of the intubating dose of neuromuscular blocker was allowed to occur spontaneously until the first twitch of the train-of-four (T1) reached 50% of baseline, and then VEC 0.025 mg/kg (0.5 x 95% effective dose [ED(95)]) was administered. The onset, duration, and recovery to T1 = 25% and 50% were recorded. The durations of action (recovery of T1 25%) after intubating doses of RAP, VEC, and SUC were 13.7 +/- 5.3, 43.2 +/- 13.2, and 9.2 +/- 3.7 min (mean +/- SD), respectively (P < 0.0001). The times to maximum depression of T1 after a maintenance dose of VEC (0.5 x ED(95)) were 5.4 +/- 2.9, 5.1 +/- 2.5, and 5.3 +/- 2.8 min (mean +/- SD) for the RAP, VEC, and SUC groups, respectively. Recoveries to T1 25% after VEC for the RAP, VEC, and SUC groups were 18.9 +/- 11.5, 21.5 +/- 8.03, and 12.8 +/- 8.4 min, and at T1 50% they were 21.5 +/- 9.1, 30.8 +/- 9.5, and 15.5 +/- 9.7 min (mean +/- SD), respectively (P < 0.001, RAP and VEC versus SUC). The duration of action of a maintenance dose of VEC was similar after an intubating dose of RAP or VEC but was shortened when preceded by an intubating dose of SUC. ⋯ The duration of action of a maintenance dose of vecuronium was longer after an endotracheal intubating dose of rapacuronium compared with succinylcholine.
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Anesthesia and analgesia · May 2001
Randomized Controlled Trial Multicenter Study Comparative Study Clinical TrialA randomized double-blinded multicenter comparison of remifentanil versus fentanyl when combined with isoflurane/propofol for early extubation in coronary artery bypass graft surgery.
We compared a fentanyl/isoflurane/propofol regimen with a remifentanil/isoflurane/propofol regimen for fast-track cardiac anesthesia in a prospective, randomized, double-blinded study on patients undergoing elective coronary artery bypass graft surgery. Anesthesia was induced with a 1-min infusion of 0.5 mg/kg propofol followed by 10-mg boluses of propofol every 30 s until loss of consciousness. After 0.2 mg/kg cisatracurium, a blinded continuous infusion of remifentanil at 1 microg. kg(-1). min(-1) or the equivalent volume rate of normal saline was then started. In addition, a blinded bolus syringe of 1 microg/kg remifentanil or 10 microg/kg fentanyl, respectively, was given over 3 min. Blinded remifentanil, 1 microg. kg(-1). min(-1) (or the equivalent volume rate of normal saline), together with 0.5% isoflurane, were used to maintain anesthesia. Significantly more patients (P < 0.01) in the fentanyl regimen experienced hypertension during skin incision and maximum sternal spread compared with patients in the remifentanil regimen. There were no differences between the groups in time until extubation, discharge from the surgical intensive care unit, ST segment and other electrocardiogram changes, catecholamine levels, or cardiac enzymes. The remifentanil-based anesthetic (consisting of a bolus followed by a continuous infusion) resulted in significantly less response to surgical stimulation and less need for anesthetic interventions compared with the fentanyl regimen (consisting of an initial bolus, and followed by subsequent boluses only to treat hemodynamic responses) with both drug regimens allowing early extubation. ⋯ Both fentanyl and the newer opioid remifentanil, when each is combined with isoflurane and propofol, allowed for fast-track cardiac anesthesia. The remifentanil regimen used in this study resulted in significantly less hemodynamic response to surgical stimulation.
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Anesthesia and analgesia · May 2001
Randomized Controlled Trial Multicenter Study Clinical TrialProlonged epidural infusions of ropivacaine (2 mg/mL) after colonic surgery: the impact of adding fentanyl.
We evaluated the safety and efficacy of a 72-h epidural infusion of ropivacaine and measured the impact of adding fentanyl 2 microg/mL to the required infusion rate, on the quality of postoperative pain relief and the incidence of side effects, after colonic surgery. One hundred fifty-five patients scheduled for elective colonic surgery were randomized in this trial. Epidural infusions of ropivacaine 2 mg/mL with fentanyl 2 microg/mL (R + F) and without fentanyl (R) were commenced during surgery and continued for 72 h postoperatively. This was a prospective, randomized, double-blinded, multi-center trial. The median infusion rate required was less in the R + F group (9.3 vs 11.5 mL/h, P < 0.001). Median pain scores at rest and on coughing were lower in the R + F group (P < 0.0001). The incidence of hypotension was more in the R + F group (P = 0.01). Time to readiness for discharge was delayed in the R + F group (median 6.6 vs 5.5 days, P = 0.012). The addition of fentanyl to ropivacaine resulted in decreased infusion rates and enhanced pain control; however, adverse effects were increased and readiness to discharge was delayed. ⋯ Epidural infusions of ropivacaine with and without fentanyl were administered to patients to control pain after colonic surgery. Patients who received ropivacaine with fentanyl had better pain control, increased side effects, and delayed readiness to discharge. This study questions the value of adding opioids to epidural infusions of local anesthetics.
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Anesthesia and analgesia · May 2001
Randomized Controlled Trial Multicenter Study Clinical TrialThe efficacy and resource utilization of remifentanil and fentanyl in fast-track coronary artery bypass graft surgery: a prospective randomized, double-blinded controlled, multi-center trial.
We compared (a) the perioperative complications; (b) times to eligibility for, and actual time of the following: extubation, less intense monitoring, intensive care unit (ICU), and hospital discharge; and (c) resource utilization of nursing ratio for patients receiving either a typical fentanyl/isoflurane/propofol regimen or a remifentanil/isoflurane/propofol regimen for fast-track cardiac anesthesia in 304 adults by using a prospective randomized, double-blinded, double-dummy trial. There were no differences in demographic data, or perioperative mortality and morbidity between the two study groups. The mini-mental status examination at postoperative Days 1 to 3 were similar between the two groups. The eligible and actual times for extubation, less intense monitoring, ICU discharge, and hospital discharge were not significantly different. Further analyses revealed no differences in times for extubation and resource utilization after stratification by preoperative risk scores, age, and country. The nurse/patient ratio was similar between the remifentanil/isoflurane/propofol and fentanyl/isoflu-rane/propofol groups during the initial ICU phase and less intense monitoring phase. Increasing preoperative risk scores and older age (>70 yr) were associated with longer times until extubation (eligible), ICU discharge (eligible and actual), and hospital discharge (eligible and actual). Times until extubation (eligible and actual) and less intense monitoring (eligible) were significantly shorter in Canadian patients than United States' patients. However, there was no difference in hospital length of stay in Canadian and United States' patients. We conclude that both anesthesia techniques permit early and similar times until tracheal extubation, less intense monitoring, ICU and hospital discharge, and reduced resource utilization after coronary artery bypass graft surgery. ⋯ An ultra-short opioid technique was compared with a standard fast-track small-dose opioid technique in coronary artery bypass graft patients in a prospective randomized, double-blinded controlled study. The postoperative recovery and resource utilization, including stratification of preoperative risk score, age, and country, were analyzed.
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Anesthesia and analgesia · May 2001
Randomized Controlled Trial Comparative Study Clinical TrialA comparison of 0.0625% bupivacaine with fentanyl and 0.1% ropivacaine with fentanyl for continuous epidural labor analgesia.
We compared the analgesic efficacy and the degree of motor block achieved with epidural infusion of 0.0625% bupivacaine (Group B) versus 0.1% ropivacaine (Group R), both with 0.0002% fentanyl (2 microg/mL) in laboring patients. A prospective, double-blinded study was performed in 98 ASA physical status I-II parturients who were divided randomly into two groups to receive either bupivacaine or ropivacaine after catheter location had been tested with an initial bolus of lidocaine and fentanyl. The infusion rate was 15 mL/h in every case. When pain was perceived, 5-mL boluses of the assigned epidural analgesic were administered every 10 min until analgesia was achieved. We recorded pain intensity, level of sensory block, degree of motor block, hemodynamic variables, secondary effects, mode of delivery, neonatal outcome, and patient satisfaction. There were no statistically significant differences in any of the factors analyzed. Highly effective analgesia was achieved in both groups with a small incidence of motor block. These findings suggest that bupivacaine may be more potent than ropivacaine. ⋯ We compared different concentrations of epidural bupivacaine and ropivacaine thought to be equipotent. Both solutions were equally efficient in providing highly effective epidural analgesia for labor with minimal motor block. These findings suggest that bupivacaine may be more potent than ropivacaine.