Neuraxial Morphine Anesthesia Given During Cesarean Delivery and Risk of Urinary Retention: A Retrospective Study.

Background: Cesarean deliveries (CD) are commonly performed using neuraxial anesthesia. The use of neuraxial morphine has proven beneficial in terms of postoperative pain management; however, its effect on postoperative urine retention remains unclear.
Objectives: To determine whether morphine injection into the neuraxis during CD influences postoperative urinary retention rate.
Methods: We conducted a retrospective case-control observational study of patients undergoing CD. We compared patients using morphine injected into the intrathecal or epidural spaces (November 2020 to October 2021) to a historical cohort of patients undergoing CD without morphine (November 2019 to October 2020). The primary outcome was the rate of postoperative overt urinary retention necessitating bladder catheterization.
Results: The study group comprised 283 patients, and 313 patients in the control group were eligible for analysis. No differences were found with respect to the baseline demographic and indication for CD. The number of postpartum urinary bladder catheterizations due to urine retention was higher in the study group (5% vs. 1%, P-value = 0.003). No cases of 30-day readmission were recorded. Moreover, patients treated with neuraxial morphine required fewer repeat doses of postoperative anesthesia (oral analgesia 7.4 vs. 10.1, intravenous analgesia 0.29 vs. 0.31, oral opioids 0.06 vs. 3.70, intravenous opioids 0.01 vs. 0.45, P-value < 0.001 for all).
Conclusions: While neuraxial morphine used during CD appears to be safe and effective, the risk of postoperative urinary retention seems to be increased due to its use. Cases of overt urinary retention treated by bladder catheterization does not lead to short-term complications.