GENERAL ANESTHESIA--this is when a patient is asleep deeply to the
point of unconsciousness. It is deeper than when you are asleep at
night. General Anesthesia is administered by an intravenous induction
or a gas induction. Induction means the patient is placed into the
sleeping state of unconsciousness. IV induction is done by giving
medications into the IV that quickly puts the patient to sleep (10-12
seconds). A gas induction is performed with a mask, where the patient,
usually a child, breaths gases from a mask until they fall asleep.
This take longer than the IV induction, on the order of a few minutes.
Mask inductions are done for children because they don’t have
an IV in place. Most infants and young children do not tolerate being
prodded or poked with needles while they are awake--so the IV is started
after they go to sleep.
Now that the patient is asleep, they need to stay asleep for the
entire time of the surgery. This is accomplished with anesthesia gases
(commonly, sevoflurane, isoflurane) or with a continuous intravenous
infusion of induction agents (usually propofol, diprivan).
How do patients wake up from this general anesthesia? In the case
of anesthesia gases, they are turned off at the end of the surgery
and the patient awakens slowly as they breathe off the gases. In the
case of IV infusions, the medicine infusion is stopped and the patient
awakens slowly as their body redistributes the medications away from
the brain, and metabolizes these medicines in the liver and excretes
them through the kidney.
During general anesthesia there is intense monitoring of the patients
vital signs: every heartbeat, every breath, is followed, along with
the exact concentration of oxygen in the patients bloodstream. These
and many other vital signs and parameters are checked frequently to
ensure they stay fully asleep during the surgery, tolerate it well,
then a safe return of the patient to consciousness when the surgeon
is finished with the procedure.
Examples of types of surgeries that are performed under general anesthesia
include: gynecologic surgery BTL's laparoscopy, laparoscopic cholecystectomy
(gallbladder surgery), inguinal and ventral hernia repairs, abdominal
surgery like colon resections, appendectomy, small and large bowel
surgery, head and neck surgery such as tonsillectomy and adenoidectomy(T/A
or TA), bilateral myringotomy tube placements (BMT's, children’s
ear tubes), thyroidectomy, gastric bypass, peptic ulcer and duodenal
ulcer surgery, gastroesophageal surgery, orthopedic surgery, plastic
surgery like breast implants/augmentation, facial and facelifts, abdominoplasty,
and of course heart/lung/cardiac/thoracic surgery, and neurosurgery.
