To the Editor:-We read with great interest the study by Gautier et al. in the March issue of Anesthesiology. Clinical trials to evaluate the interactions of analgesics at the spinal cord level are very important. Gautier et al. present only the maximum pain relief score, the time at which this occurred, and the duration of adequate analgesia (i.e., time to first analgesic request after intrathecal injection). However, two agents that share these three parameters may not be equally effective (as illustrated in Figure 1using hypothetical data). A similar comprehensive description of side effects may be useful in analyzing their incidence and severity. Furthermore, such analysis may provide useful information on possible synergistic or additive interactions between sufentanil and clonidine in this particular clinical setting.
Leonidas C. Goudas, M.D., Ph.D.
Assistant Professor, Research
Daniel B. Carr, M.D., F.A.B.P.M.
Saltonstall Professor of Pain Research; Department of Anesthesia; New England Medical Center; Boston, Massachusetts;firstname.lastname@example.org
(Accepted for publication August 6, 1998.)