Neuraxial opioids for post-cesarean delivery analgesia: can hydromorphone replace morphine? A retrospective study.

Background: Cesarean delivery is the most common surgical procedure performed in the USA. We evaluated the postoperative analgesic properties of neuraxial hydromorphone compared to neuraxial morphine for post-cesarean delivery analgesia.

Methods: A retrospective chart review was performed of women who underwent cesarean delivery and received neuraxial anesthesia from March to November 2011 and from March to November 2012. A total of 450 patients received intrathecal morphine 200μg and 387 patients received intrathecal hydromorphone 60μg. Eighty-one patients received epidural morphine 3mg and 102 patients received epidural hydromorphone 0.6mg.

Results: Median time to first opioid after intrathecal morphine was 17.0h versus 14.6h after intrathecal hydromorphone (P<0.0001). Patients who received intrathecal hydromorphone consumed more opioids in the first 24h; 37.0mg versus 26.4mg oral morphine equivalents (P<0.001). The side effect profile between the intrathecal groups was similar. Median time to first opioid with epidural morphine was 20.1h versus 13.0h with epidural hydromorphone (P=0.0007). Total opioid consumption was not significantly different between the epidural groups. The side effect profiles were similar.

Conclusions: Hydromorphone is a reasonable alternative to morphine for post-cesarean delivery analgesia. With the dosing used in our study, analgesia from morphine lasted longer than hydromorphone via intrathecal and epidural routes; however, neuraxial hydromorphone remains a reasonable option for long-acting analgesia post cesarean delivery.