Monitored Anesthesia Care for Abdominal Surgery
Monitored anesthesia care is a mode of anesthesia in which an anesthesia clinician continually monitors and supports a patient’s vital functions, diagnoses and treats clinical problems, administers sedative or analgesic medications, and converts to general anesthesia as needed 1. Nearly one-third of ambulatory anesthesia services for diagnostic or therapeutic procedures in the United States are provided in the form of monitored anesthesia care, most often in locations outside of the operating room 2. This approach is suitable for many different procedures. This article will discuss the use of monitored anesthesia care for abdominal surgery.
In general, deciding on the anesthesia strategy requires careful consideration of the type of procedure, patient co-morbidities, and individual preferences. In monitored anesthesia care (MAC), the choice of a sedative or analgesic and dosage is based on the required depth of sedation and analgesia. Sedatives and analgesics should only be infused after carefully assessing the patient’s level of consciousness and hemodynamic variables, since excessively heavy sedation could result in central respiratory depression or airway obstruction. The presence of a sufficiently experienced anesthesiologist, as well as oxygen supply, monitoring devices and emergency equipment, are essential during the entire course of MAC 3.
Patients presenting for abdominal surgery (such as abdominal wall reconstruction) are clinically complex. For example, obesity, sleep apnea, hypertension, and cardiovascular disease commonly affect patients with an abdominal wall defect. As a result, cardiac output and pulmonary function may be compromised. Patients with chronic obstructive pulmonary disease are also more likely to cough during the postoperative awakening process, which can affect the smooth reconstruction of the abdominal fascia. It is important that the surgical team remain acutely aware of the challenges associated with abdominal surgery and anesthesia for the procedure. A collaborative, cross-specialty effort is necessary to maximize patient outcomes in the context of abdominal surgery.
Patients who need abdominal surgery, such an abdominal wall reconstruction, may warrant special preoperative considerations. Patients with obesity are at a greater risk for other health complications, including coronary artery disease, hyperlipidemia, degenerative disk disease, diabetes, obstructive sleep apnea, and hypertension. Hypertension should be controlled preoperatively. Patients who may have undergone bariatric surgery prior to an abdominoplasty should be assessed for vitamin and nutritional deficiencies. Intraoperatively, obstructive sleep apnea should also be prevented, and the airway very carefully managed 4.
Monitored anesthesia care for abdominal surgery means that an anesthesia provider will be with the patient throughout the entire procedure to provide sedatives and medications. The amount of medication will be carefully measured to yield moderate to deep sedation such that the procedure is guaranteed to be performed with minimal anxiety or discomfort. The patient will not be under general anesthesia, though the anesthesia provider and surgical team must be ready to transition to general anesthesia if needed. Both during and following the procedure, the anesthesiologist will continuously monitor a patient’s heart rate, blood pressure, breathing, and level of alertness 5.
The use of monitored anesthesia care for abdominal surgery presents a number of benefits compared to general anesthesia, including reduced postoperative pain, a faster recovery, and a lower risk of complications. However, monitored anesthesia care is not suitable for all abdominal surgery patients, and the decision to use it should be carried out by the anesthesia care team on an individual basis, based on the clinical context 6.
In many cases, MAC is preferred over general or regional anesthesia due to its cost-effectiveness and rapid recovery rate. Additional clinical research remains to be conducted in order to specify its range of applications and optimal context-dependent parameters, especially in more invasive procedures like abdominal surgery.
References
1. Monitored anesthesia care in adults – UpToDate [Internet]. [cited 2023 Mar 31]. Available from: https://www.uptodate.com/contents/monitored-anesthesia-care-in-adults
2. Bayman EO, Dexter F, Laur JJ, Wachtel RE. National Incidence of Use of Monitored Anesthesia Care. Surv Anesthesiol. 2012; doi: 10.1213/ANE.0b013e31821c3e8e.
3. Sohn HM, Ryu JH. Monitored anesthesia care in and outside the operating room. Korean Journal of Anesthesiology. 2016.
4. Slabach R, Suyderhoud JP. Anesthetic Considerations for Abdominal Wall Reconstructive Surgery. Semin Plast Surg. 2012;26(1):12. doi: 10.1055/s-0032-1302460
5. Types of Anesthesia Care | Department of Anesthesiology [Internet]. [cited 2023 Mar 31]. Available from: https://anesthesiology.weill.cornell.edu/patients/types-anesthesia
6. Das S, Ghosh S. Monitored anesthesia care: An overview. Journal of Anaesthesiology Clinical Pharmacology. 2015. doi: 10.4103/0970-9185.150525