General anesthesia medications can be inhaled or
injected into a vein. They affect your entire body, making you unconscious.
General anesthesia also causes forgetfulness (amnesia) and relaxation of the
muscles throughout your body. Under anesthesia, you should be completely
unaware and should not feel pain during childbirth. Although general anesthesia
takes effect much faster than epidural or spinal anesthesia, it has more risks.
General anesthesia is therefore rarely used during childbirth. It is generally
used when an emergency caesarean delivery is necessary and an
epidural catheter, which can provide numbing
anesthesia from the waist down, has not been installed in advance.
General anesthesia is commonly started through a vein (intravenous anesthetic), but it may also be inhaled
(inhalation anesthetic). Once you are unconscious, anesthesia may be maintained
with an inhalant anesthetic alone, with one or more intravenous anesthetics, or
a combination of the two.
General anesthesia slows many of your body’s normal automatic
functions, such as those that control breathing, heartbeat, circulation of the
blood (such as blood pressure), movements of the digestive system, and throat
reflexes such as swallowing, coughing, or gagging that prevent foreign material
from being inhaled into your lungs (aspiration). Because anesthesia has such a
powerful influence on your body, an anesthesia specialist must carefully
maintain a balance of medications while monitoring your heart, breathing, blood
pressure, and other vital functions. A tube inserted into the nose or mouth and
into the windpipe, or trachea (called an
endotracheal, or ET, tube), or a shorter tube with a
mask inserted as far as the larynx (laryngeal mask airway) is usually used to
give an inhalant anesthetic and oxygen, to control and assist breathing. An ET
tube is used to prevent breathing in stomach acid, which would damage the
lungs.
How quickly you recover from general anesthesia depends on the dose
of medication you received, your body's response to it, and whether you
received other medications that may prolong your recovery. As you begin to
awaken from general anesthesia, you may experience some confusion,
disorientation, or difficulty thinking clearly. This is normal. It is also
fairly common to have nausea, vomiting, or a slightly lowered body temperature.
It may take some time before the effects of the anesthesia are completely
gone.