special subjects
Postoperative Care
Urinary retention and constipation
Urinary retention and constipation are common after surgery. Causes include Anticholinergics Opioids Immobility Decreased oral intake Urine output must be monitored. Straight catheterization is typically necessary for patients who have a distended bladder and are uncomfortable or who have not urinated for 6 to 8 hours after surgery; the Credé maneuver (application of suprapubic pressure during voiding) sometimes helps and may make catheterization unnecessary. Chronic retention is best treated by avoiding causative drugs and by having patients sit up as often as possible.Bethanechol5 to 10 mg orally can be tried in patients unlikely to have any bladder obstruction and who have not had a laparotomy; doses can be repeated every hour up to a maximum of 50 mg/day. Sometimes an indwelling bladder catheter is needed, especially if patients have a history of retention or a large initial output after straight catheterization. However, an indwelling catheter should be removed as soon as possible to decrease the risk of infection. Constipationis common and typically secondary to anesthetic drugs, bowel surgery, postoperative immobility, and opioids. Constipation is treated by minimizing use of opioids and other constipating drugs, by beginning postoperative ambulation early, and, if patients have not had gastrointestinal surgery, by giving stimulant laxatives (eg,bisacodyl,senna, cascara). Stool softeners (eg,docusate) do not alleviate postoperative constipation. 