Monday, November 30, 2015
What Exactly is Monitored During MAC?
I am having lacrimal duct surgery performed for a blocked tear duct. The surgeon is using monitored care anesthesia with sedatives. He said I would be very drowsy and possibly asleep. This is unclear to me. I would like to be prepared to ask the anesthesiologist a few questions regarding this type of anesthesia. Any light you can shed on the topic would be helpful. Will I need to be intubated? Will I be monitored? Is this type of anesthesia suitable for this surgery? What is the recovery like? Will I remember the procedure? How is the anesthesia administered?
The following detailed definition of "monitored anesthesia care" (MAC) is from the American Society of Anesthesiologists:
"Monitored anesthesia care is a specific anesthesia service in which an anesthesiologist has been requested to participate in the care of a patient undergoing a diagnostic or therapeutic procedure.
Monitored anesthesia care includes all aspects of anesthesia care - a preprocedure visit, intraprocedure care and postprocedure anesthesia management.
During monitored anesthesia care, the anesthesiologist or a member of the anesthesia care team provides a number of specific services, including but not limited to:
- Monitoring of vital signs, maintenance of the patient`s airway and continual evaluation of vital functions
- Diagnosis and treatment of clinical problems which occur during the procedure
- Administration of sedatives, analgesics, hypnotics, anesthetic agents or other medications as necessary to ensure patient safety and comfort
- Provision of other medical services as needed to accomplish the safe completion of the procedure.
Monitored anesthesia care often includes the administration of doses of medications for which the loss of normal protective reflexes or loss of consciousness is likely.
Monitored anesthesia care refers to those clinical situations in which the patient remains able to protect the airway for the majority of the procedure. If, for an extended period of time, the patient is rendered unconscious and/or loses normal protective reflexes, then anesthesia care shall be considered a general anesthetic."
The choice of a particular anesthetic technique (MAC, general anesthesia, regional anesthesia) is normally a decision made by the anesthesiologist, taking into account the type of surgery as well as the needs and preferences of both the patient and the surgeon.
A monitored anesthesia care technique usually involves the administration of intravenous anesthetic drugs, oxygen (given with a nasal cannula or face mask), and standard patient monitoring procedures similar to those used during a general anesthetic. MAC implies that the trachea (windpipe) is not intubated. Because MAC usually entails the administration of lower doses of anesthetic drugs than with a general anesthetic, the recovery period tends to be shorter. The drugs that are used definitely affect one`s ability to remember the procedure, but periods of awareness can occur.
Please consult your anesthesiologist before your surgery to establish what is planned for you and to answer any other specific questions.
Gareth S Kantor, MD
Assistant Professor of Anesthesiology
School of Medicine
Case Western Reserve University