Surgery risks go up depending upon the anesthesiologist's workload

A new study appearing in JAMA Surgery from a team at the University of Michigan examines whether the number of overlapping procedures managed by the anesthesiologist increases the risk of death or complications after surgery.

Using data from the Multicenter Perioperative Outcomes Group electronic health record registry, the team investigated surgical procedures that involved an anesthesiologist directing a CRNA or an anesthesiology resident. This anesthesia care team model is the most common model used to deliver anesthesia in the United States.

Focusing their analysis on cases with CRNA involvement and minimal anesthesiology resident involvement they identified patients with similar demographics and health statuses who underwent surgical cases of various types, including general, gynecologic, neurologic, otolaryngologic, orthopedic, urologic and vascular procedures. For each patient, they calculated the average number of concurrent surgeries that were managed by that patient's anesthesiologist during the patient's procedure. They then compared instances where the anesthesiologist was directing one, between one to two, two to three, or three to four cases at a time.

Overall, 5.19% of cases resulted in some form of post-surgical complication (30-day mortality or one of six major surgical morbidities: cardiac, respiratory, gastrointestinal, urinary, bleeding, and infectious complications).

When compared to an anesthesiologist directing anesthesia for one to two overlapping surgeries, directing anesthesia for two to three or three to four overlapping surgeries led to an increase in the rate of morbidity and mortality. Instances where the anesthesiologist was directing three to four surgeries at a time had a complication rate of 5.75%, a 14% increase compared to the complication rate of 5.06% for one to two overlapping surgeries.

Researchers concluded that anesthesiologists have been saying for a long time that covering four rooms is possible but should be reserved for situations where we think it's safe. Increasing overlapping responsibilities may have some potential downsides that balance the advantages of potential cost savings and access to care.

Reference: "Surgery risks go up depending upon the anesthesiologist's workload"; JAMA Surgery DOI-10.1001/jamasurg.2022.2804.