The most frequent cause of delayed emergence (when the patient fails to regain consciousness within an expected period of time after general anesthesia) is residual drug effect. Delayed emergence may occur as a result of an absolute or relative drug overdose. The effects of preoperative sleep deprivation or drug ingestion (alcohol, sedatives) can be additive to those of anesthetic agents in producing prolonged emergence. Intravenous naloxone (in 80 μg increments in adults) and flumazenil (in 0.2 mg increments in adults) will readily reverse the effects of an opioid or benzodiazepine, respectively. Intravenous physostigmine (1–2 mg) may partially reverse the effect of other agents. A nerve stimulator can be used to exclude persisting neuromuscular blockade in poorly responsive patients on a mechanical ventilator who have inadequate spontaneous tidal volumes. Less common causes of delayed emergence include hypothermia, marked metabolic disturbances, and perioperative stroke.
TRANSPORT FROM THE OPERATING ROOM TO THE PACU
Patients emerging from anesthesia should not leave the operating room until they have a patent airway, have adequate ventilation and oxygenation, and are hemodynamically stable; qualified anesthesia personnel must attend the transfer to the PACU. Transient hypoxemia (SpO2 < 90%) may develop in as many as 30–50% of otherwise “normal” patients during transport while breathing room air; we recommend supplemental oxygen for all transported patients, especially if the PACU is not in immediate proximity to the operating room. Unstable patients should remain intubated and should be transported with a portable monitor (ECG, SpO2, and blood pressure) and a supply of emergency drugs.
Airway patency, vital signs, oxygenation, and level of consciousness must be assessed immediately upon PACU arrival. Subsequent blood pressure, heart rate, and respiratory rate measurements are routinely made at least every 5 min for 15 min, or until stable, and every 15 min thereafter. Pulse oximetry and ECG are monitored continuously in all patients. In awake PACU patients, neuromuscular function should be assessed clinically (eg, head-lift and grip strength). At least one temperature measurement must also be obtained. Pain, the presence or absence of nausea or vomiting, and the adequacy of hydration and output (including urine flow, surgical drainage, and bleeding) should be assessed. After initial vital signs have been recorded, the anesthesia provider should give a report to the PACU nurse that includes (1) relevant preoperative history (including mental status and any communication problems, such as language barriers, deafness, blindness, or mental disability); (2) pertinent intraoperative events (type of anesthesia, the surgical procedure, blood loss, fluid replacement, antibiotic and other relevant medication administration, and any complications); (3) any expected postoperative problems; (4) any anticipated need for PACU medication administration, such as antibiotics; and (5) postanesthesia orders. Postoperative orders should address analgesia and nausea/vomiting therapy; epidural or perineural catheter care, including the need for acute pain service involvement; ...