A double-blind, randomized comparison of low-dose rocuronium and atracurium in a desflurane anesthetic.

STUDY OBJECTIVES: To compare the neuromuscular and hemodynamic effects of rocuronium and atracurium when administered during a desflurane-based anesthetic. DESIGN: Randomized, double-blind clinical trial. PATIENTS: 51 adult ASA physical status I and II patients scheduled for general surgical operations. SETTING: University-based NCI-designated cancer center. INTERVENTIONS: Patients received either 0.45 mg/kg rocuronium (n = 28) or atracurium 0.5 mg/kg (n = 23). Induction of anesthesia was accomplished by 2 microg/kg fentanyl intravenously (IV) and 1.5 mg/kg propofol IV and maintained by a nitrous oxide/oxygen desflurane anesthetic. MEASUREMENTS AND MAIN RESULTS: A neuromuscular monitor was used at the adductor pollicis to monitor and record twitch response to train-of-four electrical stimulation. Baseline heart rate (HR) and blood pressure (BP) were measured and again at 2, 5, 10, and 15 minutes after muscle relaxant administration. Patients in the rocuronium group were found to have shorter times to 80%T(1)depression (109 +/- 53 vs. 135 +/- 47 sec), although those differences did not reach statistical significance (p = 0.07). Percent of the first twitch (T(1) ) was significantly lower in the patients receiving rocuronium at 60 seconds (53 +/- 24 vs. 73 +/- 27 sec; p = 0.006) and 90 seconds (25 +/- 22 vs. 47 +/- 29 sec; p = 0.003) than in the patients receiving atracurium. Duration was shorter in rocuronium-treated patients (25% T(1) recovery = 32 +/- 12 vs. 54 +/- 14 min; p < 0.001) than the patients receiving atracurium. Intubation scores were better at 60 seconds after muscle relaxant administration in the rocuronium group. No significant differences in HR or BP were seen between the patients in the two groups. CONCLUSIONS: Rocuronium at a dose of 0.45 mg/kg possesses a fairly rapid onset of neuromuscular blockade and has short:intermediate duration of action when used with a desflurane anesthetic. This quality makes it a desirable drug for operations of relatively short duration. Rocuronium at a dose of 0.45 mg/kg has a faster onset and shorter duration than atracurium, at 0.5 mg/kg, when used with a desflurane anesthetic.

A multicenter evaluation of remifentanil for early postoperative analgesia.

We evaluated the use of an infusion of remifentanil to provide postoperative analgesia during recovery from total intravenous anesthesia (TIVA) with remifentanil and propofol. One hundred fifty-seven patients from seven medical centers underwent abdominal, spine, joint replacement, or thoracic surgery. Remifentanil was titrated in an effort to limit pain to 0 or 1 on a 0-3 scale. At the end of the 30-min titration period, 78% of infusion rates were in the range of 0.05 to < or = 0.15 microgram.kg-1.min-1, 5% were < 0.05 microgram.kg-1.min-1, and 17% were > 0.15 microgram.kg-1.min-1. Pain scores were 0 or 1 in 64% of patients. Nausea occurred in 35% and emesis in 8% of patients; the peak incidence of nausea followed discontinuation of the remifentanil infusion at the time of administering morphine. Respiratory adverse events (oxygen saturation by pulse oximetry [Spo2] < 90% or respiratory rate < 12) affected 29% of patients. Apnea occurred in 11 patients (7.0%). There was a large variation in the incidence of respiratory depression between the centers, ranging from 0 to 75%. The explanation for the large variability in respiratory outcome was not evident.

The effect of d-tubocurarine priming on an ED95 dose of vecuronium bromide.

STUDY OBJECTIVE: To examine how priming with ED10 d-tubocurarine prior to the administration of ED95 vecuronium bromide affects onset and duration of neuromuscular blockade. DESIGN: Prospective, randomized, observer-blinded study. SETTING: Operating room at a university cancer center. PATIENTS: 40 ASA physical status I and II patients undergoing ambulatory surgical procedures. INTERVENTIONS: Patients were randomized to one of two groups. Group 1 patients received d-tubocurarine 50 micrograms/kg intravenously (IV), followed by vecuronium 60 micrograms/kg IV. Group 2 patients received vecuronium 60 micrograms/kg IV without priming. All patients received a total IV anesthetic consisting of alfentanil and propofol for induction of anesthesia and propofol alone for maintenance of anesthesia. MEASUREMENTS AND MAIN RESULTS: Onset of muscle relaxation was determined with an electromyograph (Datex Relaxograph), documenting time to 80% depression of the first twitch in a train-of-four (T(1)80%), percent depression of T1 at 60 and 90 seconds (T(1)60 and T(1)90, respectively), T4:T1 ratio at 90 seconds, and time to achieve maximal blockade (Bmax). Recovery was evaluated by measuring the time required for return of T1 to 25% of the baseline value. Intubating conditions were assessed at 90 seconds after vecuronium administration and graded on a 1 (jaw tight, impossible to intubate) to 4 (jaw relaxed, vocal cords immobile) scale. All criteria measuring onset of neuromuscular blockade (i.e., T(1)80%, T(1)60, T(1)90, T4:T1, and Bmax) were significantly shorter (p < 0.05) in patients who received d-tubocurarine. Recovery was similar in both groups. Intubation scores were significantly better 90 seconds after priming (p < 0.05). CONCLUSIONS: These results indicate that crossover dosing of nondepolarizing muscle relaxants may have synergistic effects. Priming with ED10 d-tubocurarine prior to an ED95 dose of vecuronium shortens the time to 80% T1 depression and produces satisfactory intubating conditions at 90 seconds, without prolonging the duration of the Therefore, d-tubocurarine is an attractive drug for priming vecuronium in short operative procedures that require muscle relaxation.

Emergency management of tracheal rupture.

We have described a patient in whom tracheal rupture occurred during prolonged mechanical ventilation. Appropriate intensive respiratory care management, including the use of the minimal leak technique, was used. Our patient unfortunately had nearly every known predisposing factor for tracheal damage.