PATIENT CARE

Patient Care in the Post Anesthetic Care Unit

Patient Care in the Post Anesthetic Care Unit

Introduction

General anesthesia is the method used when the surgery requires that the patient be unconscious and/or paralyzed. The patient is usually given an intravenous (IV), sedative/amnesic drug like midazolam first, then quickly paralylzed, intubated, and anesthetized. The patient is kept asleep with an anesthetic gas or some combination of narcotics, propofol, and neuromuscular blocking agents (see Table 1). Most of the inhalant is excreted initially through the lungs, but takes up to 24 hours to be entirely cleared. The paralyzers are reversed with an anticholinergic drug like neostigmine. This drug causes bradycardia and, therefore, is given simultaneously with glycopyrrolate or atropine. Timing is critical, as the duration of action of the paralyzing agents is longer than that of the reversal. If the reversal agent is given too soon, the patient can become reparalyzed and stop breathing when the reversal wears off.

Monitored Anesthesia Care

Monitored anesthesia care (MAC) is similar to general anesthesia in that the patient loses consciousness completely, including loss of reflexes. It requires some type of airway device, such as an oral, nasal, or laryngeal mask airway (a device that occludes the esophagus, and sits in the oropharynx). The airway does not pass through the vocal cords, and does not completely prevent aspiration of stomach contents). Usually the patient is sedated, having been given a fast-acting narcotic such as fentanyl, and a propofol infusion. When the infusion is stopped, the patient regains consciousness within minutes, without the disorientation usually associated with general anesthesia. MAC is used for short procedures such as D&Cs, foreign body removal, or implanting a venous port.

IV Sedation

With this type of anesthesia, the patient is deeply sedated, but retains reflexes. Recovery from sedation only requires oxygen, time, and monitoring of vital signs every 15 minutes for a short while. It is not considered true anesthesia, and will not be discussed further in this article.

Spinal or Epidural

Spinal or epidural anesthesia involves injecting local anesthetic and/or narcotic into the subarachnoid or epidural space. Epinephrine is sometimes used in conjunction with the anesthetic to extend its duration of action. The patient is usually sedated to a degree. This form of anesthesia is favored for orthopedic procedures involving the lower extremities, and urologic procedures. Epidurals are sometimes used for gynecologic procedures, and are also used for certain thoracic procedures for postoperative pain control. The effects of the spinal anesthetic wear off in a descending pattern, with the perineal and coccygeal areas being the last to regain sensation. Because of the loss of sympathetic tone, these patients develop a relative hypovolemia, and are given large amounts (1500-3000 cc) of IV fluid during surgery. They often need adrenergic drugs such as ephedrine or phenylephrine. Therefore, it is not uncommon for the uncatheterized patient to retain large amounts of urine. When the spinal begins to wear off, the kidneys begin to process all the fluid that was given in the OR, but the bladder is unable to function for ...