Anesthesia Management: One-Size-Fits-All Hydromorphone Dosing?
Authors: Xia S et al., Ann Emerg Med 2013 Nov 11;
Pain relief from a 1 mg dose did not vary by patient body weight.
Because hydromorphone is distributed widely into multiple tissues, weight-based dosing would seem to be the safest and most effective strategy when treating acute pain. Investigators at a single urban emergency department tested this theory by giving adults of varying weight the same dose and assessing pain relief.
They conducted a prospective, observational study involving 163 adults who required intravenous opioids for initial treatment of acute pain. All patients — ranging in weight from 45 kg to 157 kg — received the same dose of hydromorphone (1 mg). Improvement was measured on a numeric pain rating scale.
No correlation was observed between weight and change in pain at 30 minutes (the primary outcome). Only one patient (weight, 64 kg) had respiratory suppression.
This result suggests that the onset of effect of hydromorphone may not be dose-related. Instead, any dose above some threshold might activate pathways that begin to decrease pain perception. The clinical take-home message is that larger patients might not necessarily need larger initial doses; however, this does not alter the need to administer additional, individualized doses, titrating to an endpoint of pain relief for the patient.