[Postoperative restcurarization]

Abstract

Objective: Muscle relaxants have been used during anesthesia for the past 50 years but in the last decades it has been realised that their use can lead to complications. Studies have shown 20-40% incidence of restcurarization in postanesthesia care units (PACU) even if neuromuscular monitors are used during anesthesia. The purpose of this study was to estimate the frequency of postoperative muscle weakness at the Reykjavik Hospital in Iceland.

Material and methods: Sixty patients, operated for laparoscopic cholecystectomy or lumbal disc prolapse, given muscle relaxants (vecuronium or pancu notronium) during anesthesia were studied in the PACU. The 5-sec headlift test has been shown to be the best clinical sign of recovery and this sign was used to find patients with muscle weakness. Glasgow coma score (GCS) was used to evaluate if patients were too drowsy to co-operate and patients with GCS <12 were excluded. Measurements were made after arrival to the PACU and every 30 minutes thereafter until headlift was at least five seconds.

Results: Incidence of restcurarization was 17% on arrival to the PACU and these patients were significantly lower in oxygen saturation before oxygen supplementation was started. Thirty minutes after arrival 6% were still restcurarized and 3% after 60 minutes. All patients had recovered after 90 minutes. No difference was found between patients given vecuronium or pancuronium in the first two measurements but those with longest duration of muscle weakness had received pancuronium.

Conclusion: The study shows that the incidence of muscle weakness is too high, which might increase the risk for complications such as hypoxia or respiratory failure. To increase patient safety, shorter acting drugs are recommended and the use of new nervestimulators giving the train-of-four(TOF)-ratio during muscle blockade could possibly improve the situation.