Effect of postoperative extradural morphine on lower urinary tract function

Area of Science:

• Anesthesiology
• Urology
• Pharmacology

Background:

• Postoperative pain management often involves opioids.
• Epidural morphine is used for analgesia after gynecological surgery.
• Potential side effects on lower urinary tract function require investigation.

Purpose of the Study:

• To evaluate the impact of extradural morphine on lower urinary tract function post-uterine surgery.
• To assess the incidence and characteristics of urinary retention associated with epidural morphine.
• To explore the efficacy of naloxone in managing morphine-induced urinary retention.

Main Methods:

• Urodynamic measurements (cystometry, urethral pressure profilometry) were performed preoperatively and postoperatively.
• Patients received extradural morphine for pain management.
• Comparison of urodynamic parameters between patients with and without urinary retention.
• Administration of intravenous naloxone to patients with retention.

Main Results:

• Ten patients showed no significant changes in cystometry with morphine.
• Two patients developed acute urinary retention, characterized by increased bladder capacity and detrusor pressure.
• Urethral pressure profiles remained unchanged in all patients.
• Naloxone administration showed a trend towards normalizing bladder capacity in patients with retention.

Conclusions:

• Extradural morphine can significantly affect lower urinary tract function in a subset of patients.
• Acute urinary retention following extradural morphine is a potential complication.
• Naloxone may be an effective treatment for morphine-induced urinary retention.