Postoperative urinary retention in a dog following morphine with bupivacaine epidural analgesia

Urinary retention, overflow incontinence, and subsequent detrusor atony were observed following surgery in which a morphine with bupivacaine epidural injection was used for perioperative analgesia. The premise that the urinary retention may have been due to the effects of the morphine component of the epidural is discussed, along with other possible causes.