- Patients should not leave the operating room
unless they have a stable and patent airway, have adequate ventilation
and oxygenation, and are hemodynamically stable.
- 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.
- 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.
- 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.
- Hypoventilation in the PACU is most commonly
due to the residual depressant effects of anesthetic agents on respiratory
- Obtundation, circulatory depression, or severe
acidosis (arterial blood pH < 7.15) is an indication for immediate
endotracheal intubation in patients suffering from hypoventilation.
- 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.
- Increased intrapulmonary shunting from a decreased
functional residual capacity relative to closing capacity is the
most common cause of hypoxemia following general anesthesia.
- 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.
- Hypovolemia is by far the most common cause
of hypotension in the PACU.
- 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% ...