Monitored Anesthesia Cared2017-07-20T01:09:57+08:00

What is Monitored Anesthesia Care?

Monitored anesthesia care (MAC) is a specific type of anesthesia service wherein an anesthesiologist is requested to participate in the care of a patient who is undergoing a diagnostic or therapeutic procedure.

Effects of Monitored Anesthesia Care

MAC provides the patient with anxiety relief, amnesia, pain relief, comfort, and safety during the entire procedure.

Candidates for Monitored Anesthesia Care

MAC is ideal for patients undergoing uncomfortable procedures and minor surgeries that do not require the use of general anesthesia. Sometimes, MAC is solely used for non-painful procedures and often to supplement local anesthetic injections for painful ones.

Your Consultation

The anesthesiologist will interview the patient about his general health before starting the procedure. The patient will be asked about his current medical history, medications, allergies, and past medical, surgical and anesthetic information. The patient should also prepare his old medical records and lab tests in case these are needed. The doctor will give the patient instructions for taking medications, restrictions on eating and drinking prior to the procedure.

The Monitored Anesthesia Care Procedure

On the day of the procedure, the patient will receive medications through an intravenous line (IV) and the anesthesia care provider may give the patient a sedative before entering the operating suite. Inside the operating suite, monitors will be placed on the patient to assess his vital signs (blood pressure, heart rate and rhythm, oxygenation and respiration). Also, supplemental oxygen may be given if indicated. More sedation is given and then the procedure begins.

The anesthesia care provider will select the appropriate medication depending on the type of procedure and the medical condition of the patient. Local anesthetics are usually given as local injections or as nerve blocks by the surgeon or anesthesiologist. The injections used with local anesthesia will create numbness at the surgical site and provide pain relief.

The effect of MAC may range from a mild sedation to a deeper sleep. With MAC, the patient may or may not wake up from time to time during the procedure when he is stimulated. Either he may or may not remember the experience but he should remain comfortable throughout the entire procedure.


The recovery period of the patient depends on the type and length of procedure and on the kind of sedation employed. The patient’s overall tolerance to anesthetic agents and the ability to metabolize these chemicals for excretion from the body are other factors to be considered. Also, the concomitant use of other pharmaceutical agents and body habitus can affect the rate of anesthetic metabolism and overall tolerance to these agents.


Some side effects from anesthetic medications may include prolonged sedation, agitation, confusion, nausea, vomiting and respiratory depression.


What happens during monitored anesthesia care?

The monitored anesthesia care method normally involves the administration of intravenous anesthetic drugs, oxygen (given with a nasal cannula or face mask), and standard patient monitoring procedures like those used during a general anesthesia. MAC implies that the trachea is not intubated. Since MAC usually entails the administration of lower doses of anesthetic drugs compared to general anesthetic, the recovery period tends to be shorter. The drugs used can definitely affect the patient’s ability to remember the procedure, but periods of awareness can occur.

What is the state of the patient during MAC?

A patient under MAC is sedated and amnestic but remains responsive when stimulated to do so. The patient is in a light sleep and may or may not wake up from time to time during the procedure even if he does not recall doing so. The patient is able to breathe on his own and ventilation is not assisted. The patient is usually awake at the end of the procedure and can promptly be discharged from the recovery room. When a patient is undergoing a procedure with MAC, he is evaluated and monitored in the same manner as if he is having any other form of anesthesia.

What are the advantages of this procedure?

IV sedation is a good middle ground between local anesthesia (the patient is awake) and general anesthesia (the patient is asleep). This is sometimes preferred more than general anesthesia because patients have quick recovery with less nausea and vomiting. And unlike general anesthesia, the dosage of the twilight anesthesia can be limited to a level that allows the patient to respond to verbal commands and move with assistance. This would be especially helpful when the surgeon wants to see what the operative area would look like in a sitting or standing position, or with contraction of particular muscles (a technique commonly used with liposuction, breast surgery and facelift surgery).