General anesthesia is a treatment that uses a combination of intravenous drugs and inhaled gases in order to render patients unconscious during medical procedures, according to MayoClinic.com. Throughout the procedure, the patient's muscles are paralyzed, breathing must be controlled by mechanical ventilation, and vital functions must be monitored. General anesthesia is administered by a trained anesthesiologist, usually with the assistance of a certified registered nurse anesthetist.
Peripheral Nerve Damage
Peripheral nerve damage is caused by nerve compression and can occur with any form of anesthesia, as noted by Patient UK. Usually, it is brought about by the patient maintaining an exaggerated body position for long periods of time.
The extent of damage depends on the individual and the length of time spent in the position, but in some cases the recovery time may be prolonged. The nerves that are most commonly affected are the ulnar nerve and common peroneal nerve, which are nerves in the arm and leg, respectively.
Experience and research suggest potential concerns about cognitive function for patients who undergo surgery under general anesthesia, according to Harvard Health Publications. A decline in cognitive ability after surgery has been observed in both major and more minor surgical procedures.
In about 25 percent of people older than 60, cognitive difficulties may arise one week after major non-cardiac surgery. These include problems with concentration and attention. Further research has shown that this decline is usually temporary, though still long-term. After three months, the rate of affected individuals goes down to 10 percent, and after one to two years, to 1 percent.
Due to the patient's greatly reduced level of consciousness, the airway is left unprotected, according to Patient UK. If the patient vomits, there is a risk of the vomitus contents entering the lungs. This in turn can lead to lung inflammation and infection, or aspiration pneumonitis. To reduce the risk of this occurrence, patients are instructed to fast for several hours before surgery.
Complications of Anesthesia Awareness
Despite being under general anesthesia, every year nearly 30,000 patients in the U.S. "wake up" during the operation, according to Surgery Encyclopedia. Usually, the patient does not feel any pain, but is simply able to sense the surrounding environment. A minority feel the full, excruciating pain that the anesthesia was supposed to avert, however, while remaining paralyzed and unable to signal for help during the entire procedure.
Most people who experience anesthesia awareness suffer long-term psychological effects, as noted by the Royal College of Anaesthetists. These include anxiety, nightmares, sleep disturbances, fear of anesthesia, flashbacks of the event and post-traumatic stress disorder.