Delayed respiratory depression associated with 0.15 mg intrathecal morphine for cesarean section: a review of 1915 cases

PURPOSE: A low dose of morphine, given intrathecally is an effective postoperative analgesic technique and is widely used in cesarean section. Delayed respiratory depression is the most feared side effect of this technique. However, this side effect has not been thoroughly reported in the obstetric population. The aim of this study was to describe respiratory depression associated with intrathecal morphine in postcesarean women, and to estimate its incidence. METHODS: We retrospectively reviewed the obstetric anesthesia database at our institution from April 2000 to December 2006. Patients who were given 0.15 mg intrathecal morphine for cesarean section were identified. From this group, we identified patients who developed bradypnea (respiratory rate