Low-Dose Ketamine in Chronic Critical Illness.

We report a case series on the observed effects of low-dose ketamine infusions in 4 critically ill patients with varying complications related to prolonged critical illness. Doses of ketamine infusion ranged from 0.5 to 4 µg/kg/min. A low-dose ketamine infusion was used to reduce agitation in a patient requiring high doses of sedatives and analgesics. In a second patient, ketamine improved depression and anxiety symptoms. In a third patient, ketamine may have facilitated liberation from mechanical ventilation. In a fourth patient, ketamine was used for palliation to avoid lethargy. Ketamine may be considered to help decrease agitation, manage pain, facilitate opioid and benzodiazepine withdrawal, prevent respiratory depression, and potentially manage depression and anxiety in chronically critically ill patients.

Postoperative urinary retention.

Postoperative urinary retention (PUR) is a common complication of surgery and anesthesia. The risk of retention is especially high after anorectal surgery, hernia repair, and orthopedic surgery and increases with advancing age. Certain anesthetic and analgesic modalities, particularly spinal anesthesia with long-acting local anesthetics and epidural analgesia, promote the development of urinary retention. Portable ultrasound provides rapid and accurate assessment of bladder volume and aids in the diagnosis and management of PUR. Catheterization is recommended when bladder volume exceeds 600 mL to prevent the negative sequelae of prolonged bladder overdistention.