Does The Choice of Muscle Relaxants Really Affect Postoperative Recovery Time?

Abstract

To the Editor: Data published in Ballantyne and Chang's article demonstrate that the length of procedures differed greatly between the short- and intermediate-acting muscle relaxants (169 +/- 6.8 min) and the longacting muscle relaxants (256 +/- 16 min) with little, if any, overlap [1]. Regression analysis performed under these circumstances requires extrapolation well beyond the range of observation for each group-a well known pitfall in regression analysis, which should be performed only with extreme caution [2]. In addition, no information about the regression model assumed, or the corresponding parameter estimates, is given. Only the adjusted mean recovery times are given. This is especially important because the relationship as presented between length of surgery and recovery time is exponential, not linear. Furthermore, these huge differences in surgical times probably represent surgical procedures of a significantly higher complexity that result in differences in the entire associated anesthetic plan, not just the choice of muscle relaxants. Are these two groups really comparable? This article may overestimate the effect of pancuronium usage on readiness to discharge. David Bronheim, MD Mark Abel, MD Carol Bodian, PhD Department of Anesthesiology; Mount Sinai Medical Center; New York, NY 10029