Acute withdrawal syndrome related to the administration of analgesic and sedative medications in adult intensive care unit patients.

OBJECTIVES: To estimate the frequency of acute withdrawal syndrome related to the administration of analgesic and sedative medications in mechanically ventilated adult intensive care unit (ICU) patients; to identify associated clinical factors. DESIGN: Retrospective review of medical records. SETTING: An adult trauma/surgical ICU in an urban Level I trauma center. PATIENTS: Twenty-eight mechanically ventilated adult trauma/ surgical ICU patients requiring >7 days of ICU care. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Daily doses of all opioid, sedative, hypnotic, and major tranquilizer drugs administered to each patient were measured, as was duration of ICU stay, duration of mechanical ventilation, and duration of the administration of analgesic, sedative, and neuromuscular blocking agents (NMBAs) for each patient. All opioids and benzodiazepines were converted to their respective fentanyl and lorazepam equivalent units based on potency and bioavailability. Calculation of the weaning rate for each patient during tapering from opioid and benzodiazepine medications was performed. The presence or absence of acute withdrawal syndrome was identified for each patient. Nine (32.1%) patients developed acute withdrawal syndrome potentially related to the administration of analgesic or sedative medications. Patients in the withdrawal group received significantly higher mean daily (p = .049) and peak (p = .032) doses of fentanyl equivalents, as well as higher mean daily lorazepam equivalents (p = .049) compared with patients not experiencing withdrawal. Patients in the withdrawal group were also significantly more likely to have received neuromuscular blocking agents (p = .004) or propofol (p =.026) for >1 day during ICU admission compared with patients not experiencing withdrawal. Duration of mechanical ventilation (p = .049), benzodiazepine therapy (p = .048), and propofol therapy (p = .049) was also significantly longer in the group experiencing withdrawal. Withdrawal patients received a significantly lower mean daily dose of haloperidol (p = .026). There was a significant association between the development of withdrawal syndrome and the presence of ARDS (p = .017). Finally, the slopes of the lines representing opioid and benzodiazepine drug weaning were more steep for the withdrawal group, although these results did not achieve statistical significance. CONCLUSIONS: These results suggest that mechanically ventilated adult patients with extended ICU care (> or =7 days) who receive large doses of analgesic and sedative medications are at risk for acute withdrawal syndromes during drug weaning. The association between ARDS and withdrawal syndrome, combined with the observation that withdrawal syndromes were also associated with the use of neuromuscular blocking agents and prolonged mechanical ventilation, suggests that patients with ARDS may be more likely to receive high doses of analgesic and sedative medications, and are therefore at increased risk for withdrawal syndrome.

Anesthesia for combined cesarean section and extra-adrenal pheochromocytoma resection: a case report and literature review.

Pheochromocytoma during pregnancy is unusual, with approximately 250 cases now reported in the literature. The current case describes the anesthetic management of a patient with a large extra-adrenal pheochromocytoma who underwent a combined cesarean section and tumor removal in which perioperative hemodynamic control was difficult despite high-dose a-adrenergic blockade. In this case it is believed that difficulty in perioperative hemodynamic management was related to mechanical stimulation of the tumor by the gravid uterus. Review of published case reports since 1980 reveals that a pheochromocytoma during pregnancy may be diagnosed in an extra-adrenal location relatively more commonly compared to non-pregnant patients. Established criteria exist for the adequacy of alpha- and beta-adrebergic blockade for the management of pheochromocytoma in the non-pregnant patient. We discuss how these criteria apply to pregnant patients with pheochromocytoma, and suggest possible modifications to the criteria.