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Overview of complications in adults admitted to the post-anesthesia care unit

David B Glick, MD, MBA
Section Editor
Natalie F Holt, MD, MPH
Deputy Editor
Nancy A Nussmeier, MD, FAHA


Timely recognition and management of issues that arise in the immediate postoperative period saves lives, time, and money. The likelihood that a specific complication will arise for a given patient is determined by the nature of the procedure, the anesthetic techniques used, and the patient's preoperative comorbidities. The risk of some complications can be reduced with appropriate preoperative assessment and medical optimization.

The most common postoperative problems encountered in the post-anesthesia care unit (PACU) will be reviewed here. Preoperative evaluation and preventive strategies are discussed elsewhere. (See "Preoperative medical evaluation of the adult healthy patient" and "Management of cardiac risk for noncardiac surgery" and "Evaluation of preoperative pulmonary risk".)


The most common complication in the post-anesthesia care unit (PACU) is postoperative nausea and vomiting (PONV), with incidences reported between 10 and 30 percent [1,2]. A retrospective review involving 18,473 patients found an overall incidence of PACU complications of 23 percent [1]. After PONV, the most common complications were upper airway problems (6.9 percent), hypotension (2.7 percent), dysrhythmias (1.4 percent), hypertension (1.1 percent), altered mental status (0.6 percent), and suspected or major cardiac events (0.6 percent). The complications of awareness during anesthesia and visual loss may first present in the PACU and, although rare, these have received considerable attention in both the medical and lay press. (See 'Intraoperative awareness with recall' below and 'Visual disturbance' below.)

Discharge criteria scoring systems (eg, Modified Aldrete Scoring System and Postanesthetic Discharge Scoring System (table 1)) have been developed to ensure the absence of clinically significant complications in the PACU [3].


Postoperative nausea and vomiting (PONV) is the most common complication in the immediate postoperative period. Control of PONV is a necessary criterion for discharge from the post-anesthesia care unit (PACU), regardless of whether the patient is going home or will be admitted to the hospital as an inpatient. Risk factors, preventive strategies, and treatment of PONV in adults and children are discussed separately. (See "Postoperative nausea and vomiting".)


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Literature review current through: Nov 2016. | This topic last updated: Tue Nov 29 00:00:00 GMT+00:00 2016.
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