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  • Image not available.Patients should not leave the operating room unless they have a stable and patent airway, have adequate ventilation and oxygenation, and are hemodynamically stable.
  • Image not available.Before the patient is fully responsive, pain is often manifested as postoperative restlessness. Serious systemic disturbances (such as hypoxemia, acidosis, or hypotension), bladder distention, or a surgical complication (such as occult intraabdominal hemorrhage) should always be considered as well.
  • Image not available.Intense shivering causes precipitous rises in oxygen consumption, CO2 production, and cardiac output. These physiological effects are often poorly tolerated by patients with preexisting cardiac or pulmonary impairment.
  • Image not available.Respiratory problems are the most frequently encountered serious complications in the postanesthesia care unit (PACU). The overwhelming majority are related to airway obstruction, hypoventilation, or hypoxemia.
  • Image not available.Hypoventilation in the PACU is most commonly due to the residual depressant effects of anesthetic agents on respiratory drive.
  • Image not available.Obtundation, circulatory depression, or severe acidosis (arterial blood pH < 7.15) is an indication for immediate endotracheal intubation in patients suffering from hypoventilation.
  • Image not available.Following administration of naloxone to increase respiration, patients should be watched carefully for recurrence of opioid-induced respiratory depression (renarcotization), as naloxone has a shorter duration than most opioids.
  • Image not available.Increased intrapulmonary shunting from a decreased functional residual capacity relative to closing capacity is the most common cause of hypoxemia following general anesthesia.
  • Image not available.The possibility of a postoperative pneumothorax should always be considered following central line placement, intercostal blocks, rib fractures, neck dissections, tracheostomy, nephrectomies, or other retroperitoneal or intraabdominal procedures (including laparoscopy), particularly when the diaphragm might be penetrated.
  • Image not available.Hypovolemia is by far the most common cause of hypotension in the PACU.
  • Image not available.Noxious stimulation from incisional pain, endotracheal intubation, or bladder distention is usually responsible for cases of postoperative hypertension.


Recovery rooms have been in existence for less than 50 years in most medical centers. Prior to that time, many early postoperative deaths occurred immediately after anesthesia and surgery. The realization that many of these deaths were preventable emphasized the need for specialized nursing care immediately following surgery. A nursing shortage in the United States following World War II may also have contributed to centralization of this care in the form of recovery rooms where one or more nurses could pay close attention to several patients at one time. As surgical procedures became increasingly complex and were performed on sicker patients, recovery room care was often extended beyond the first few hours after surgery, and some critically ill patients were kept in the recovery room overnight. The success of these early recovery rooms was a major factor in the evolution of modern surgical intensive care units (ICU, see Chapter 49). Ironically, the recovery rooms received intensive care status relatively recently in most hospitals, where they are referred to as postanesthesia care units (PACUs). In some centers the PACU may function as overflow ICU beds (overnight) when the ICUs are full.


One of the most dramatic transformations in health care delivery during the past two decades has been a shift from inpatient to outpatient surgery (also called ambulatory surgery). It is estimated that 60–70% ...

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