Anesthesia: Types, Side Effects, And Other Information to Know

Medically reviewed by Elizabeth M. Rickerson, MD

Anesthesia is a medical treatment used to block a patient’s awareness of pain during a surgical procedure.

Are there different types of anesthesia?

There are three different types of anesthesia (or, anesthetics):

General anesthesia puts the patient in a deep sleep, and a ventilator is provided to provide the patient with oxygen during the procedure.

Local anesthesia is used for small procedures, such as mole removal, and is administered to numb the specific site of the procedure. During the procedure, the patient most often remains awake, though the doctor may provide a sedative to help the patient relax. Numbing can wear off quickly or last several hours, depending on various factors.

Regional anesthesia is similar to local anesthesia, but it numbs a larger part of the body. If a patient needs surgery on their thumb, the entire arm would be numbed. It makes recovery easier, as the injection provides pain relief both during and after surgery.

There are two types of regional anesthesia: peripheral nerve block anesthesia and epidural and spinal anesthesia. Peripheral nerve block anesthesia prevents feeling in the limbs; epidural and spinal anesthesia prevents midsection and lower-body pain.

Sedation

Sedation is also important to consider when undergoing anesthesia, according to Rickerson. Sedatives are provided by a nurse to produce a state of calm or sleep, and are often combined with anesthesia to reduce pain. 

Sedatives are given by mouth, as a liquid or a pill, or through a vein, known as intravenous (IV) medication. Sedation causes the patient to feel relaxed and sleepy and can be combined with local or regional anesthesia to reduce pain

There are three levels of sedation, based on the patient’s awareness:

Minimal sedation relaxes the patient and reduces anxiety. This is typically used for tests or procedures where the patient may feel uncomfortable, but still allows them to remain awake and to speak.

Moderate sedation, also known as conscious sedation, reduces pain and lowers awareness. Often used for minor surgeries, patients respond differently in this level of sedation. Some can still speak and respond, where others fall into a light sleep; some patients do not remember the procedure afterwards.

Deep sedation makes the patient unaware of the procedure. The patient can respond to pain; however, pain medication is used to limit discomfort. It is unlikely the patient can speak or answer questions, and they are usually given drugs that affect memory, preventing them from remember the procedure afterwards.

Which anesthetic is best for me?

The best type of anesthesia for you depends on four main factors:

  • The type of surgery you are having
  • The state of your heath
  • What your surgeon needs in order to do the procedure

These factors provide a baseline for choosing an anesthetic. “There are a lot of factors when it comes to choosing an anesthetic: it depends on what you’re having done and who is willing to do what,” Rickerson says. “If you walk in and want a procedure done, one doctor may suggest one anesthetic, while another might suggest a different one.”

Can I eat or drink before undergoing anesthesia?

It is recommended you stop eating at least eight hours before your procedure, Rickerson notes. To prevent vomiting during surgery, it is best to receive anesthesia on an empty stomach. Unless instructed otherwise by your doctor, you may drink clear fluids (water, black coffee, fruit juice without pulp) up to two hours before surgery.

Who provides anesthesia?

An anesthesiologist or a certified registered nurse anesthetist (CRNA) administers anesthesia to patients prior to the procedure.

What are the side effects of anesthesia?

Side effects of anesthesia can occur during and after the procedure. Most are minor, temporary, and result from general anesthesia. These can include nausea and vomiting, sore throat, postoperative delirium (confusion after regaining consciousness), muscle aches, itching, chills and shivering.

“Patients undergoing anesthesia can reduce their risk of side effects by ensuring a physician anesthesiologist is involved in their care,” Rickerson advises. “Before surgery or undergoing a procedure, discuss with them any medical history or health and lifestyle habits. This information helps the physician anesthesiologist know how the patient might react to anesthesia, and therefore can take steps to lower the risk of side effects.”