Prophylactic Intrathecal Morphine and Prevention of Post–Dural Puncture Headache: A Randomized Double-blind Trial

Abstract

Background: Prophylactic epidural morphine administration after unintentional dural puncture with a large-bore needle has been shown to decrease the incidence of post–dural puncture headache. The authors hypothesized that prophylactic administration of intrathecal morphine would decrease the incidence of post–dural puncture headache and/or need for epidural blood patch after unintentional dural puncture. Methods: Parturients with an intrathecal catheter in situ after unintentional dural puncture with a 17-g Tuohy needle during intended epidural catheter placement for labor analgesia were enrolled in this randomized, double-blind trial. After delivery, subjects were randomized to receive intrathecal morphine 150 µg or normal saline. The primary outcome was the incidence of post–dural puncture headache. Secondary outcomes included onset, duration, and severity of post–dural puncture headache, the presence of cranial nerve symptoms and the type of treatment the patient received. results: Sixty-one women were included in the study. The incidence of post–dural puncture headache was 21 of 27 (78%) in the intrathecal morphine group and 27 of 34 (79%) in the intrathecal saline group (difference, −1%; 95% CI, −25% to 24%). There were no differences between groups in the onset, duration, or severity of headache, or presence of cranial nerve symptoms. Epidural blood patch was administered to 11 of 21 (52%) of the intrathecal morphine group and 10 of 27 (37%) of subjects in the intrathecal saline and (difference 15%; 95% CI, −18% to 48%). conclusions: The present findings suggest that a single prophylactic intrathecal morphine dose of 150 µg administered shortly after delivery does not decrease the incidence or severity of post–dural puncture headache after unintentional dural puncture. This study does not support the clinical usefulness of prophylactic intrathecal morphine after an unintentional dural puncture.