Hartford Hospital

Search for

Moderate Sedation

(Conscious Sedation; Monitored Anesthesia Care; MAC; Sedation, Conscious; Sedation, Moderate)

En Español (Spanish Version)

Definition | Reasons for Procedure | Possible Complications | What to Expect | Call Your Doctor


Moderate sedation is used during surgery. It will put you in a comfortable, sleepy, and pain-free state. Moderate sedation is different from general anesthesia because it does not require breathing support. It will also be easy to arouse you, so you can respond to questions or commands during surgery.

Reasons for Procedure

Moderate sedation can be used for a range of procedures. If your overall health is poor, your doctor may recommend this type of sedation instead of general anesthesia.

The potential benefits include:

  • Faster recovery time
  • Fewer complications

Also, moderate sedation does not require you to be connected to a ventilator.

Possible Complications

Potential problems are rare. But all procedures have some risk. Your doctor will review potential problems, like:

  • Nausea and vomiting
  • Headache
  • Temporary memory problems—you may be unable to recall the surgery
  • Breathing problems during the surgery

Factors that may increase the risk of problems include:

  • Smoking
  • Advanced age
  • Obesity
  • Poor overall health, such as cardiovascular disease

Talk to your doctor about these risks before the procedure.

What to Expect

You will meet with an anesthesiologist who will evaluate you and ask about:

  • Your medical history, including any previous reaction to anesthetics
  • Medicines that you are currently taking (including prescription drugs, over-the-counter products, herbs, and supplements)

You may be instructed to:

  • Avoid eating and drinking 8-12 hours before the surgery
  • Take an anesthetic the morning of the surgery

The anesthetic drugs and other medicines will be delivered by an IV in your arm. The doctor may also use local anesthesia at the surgery site.


Copyright © Nucleus Medical Media, Inc.

You will be carefully monitored during the surgery. Your medicines may need to be adjusted to keep a certain level of sedation. The goal will be to make sure you are comfortable and pain-free.

Your sedation may be increased so that you are fully asleep. If this is the case, a ventilator will be used to support your breathing.

The hospital staff will monitor your vital signs.

You will not have any pain during the surgery.

The length of your stay will depend on the reason you had surgery. You may be able to go home the same day as the procedure. However, you may need to stay a few nights.

If you are discharged on the same day as the surgery, do not drive or operate machinery. The medicines can affect your mental and physical abilities.

Call Your Doctor

Call your doctor if any of these occur:

  • Signs of infection (such as, fever, chills)
  • Nausea and vomiting
  • Pain that cannot be controlled with the medicines that you were given
  • Cough, shortness of breath, chest pain
  • Dizziness, lightheadedness

If you have an emergency, call for medical help right away.


American Association of Nurse Anesthetists


American Society of Anesthesiologists


Canadian Resources:

Canadian Anesthesiologists' Society



American Society of Anesthesiologists. Distinguishing monitored anesthesia care (MAC) from moderate sedation/analgesia (conscious sedation). 2009;Oct 21.

Bayman E, Dexter F, et al. National incidence of use of monitored anesthesia care. Anesth Analg. 2011;113(1):165-169.

Furstein J, Patel M, et al. Use of dexmedetomidine for monitored anesthesia care for diskography in adolescents. AANA Journal. 2011;79(5):421-425.

Ghisi D, Fanelli A, et al. Monitored anesthesia care. Minerva Anestesiol. 2005;71(9):533-538.

Monitored anesthesia care. Northeastern Anesthesia Services website. Available at: http://www.northeasternanesthesia.com/youranasthesia/care.php. Accessed August 1, 2012.

Monitored anesthesia care (MAC). Berkshire Health Systems website. Available at: http://www.bhs1.org/body.cfm?id=1664. Accessed August 1, 2012.

Thompson K. Monitored anesthesia care. University of North Carolina at Chapel Hill website. Available at: http://www.unc.edu/~rvp/old/RP_Anesthesia/Barash/Ch47_MAC.html. Accessed August 1, 2012.

Last reviewed September 2013 by Marcin Chwistek, MD

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.

CreativeChangePowered by: Creative Change, Inc.