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News • Workload evaluation

When anaethesiologists are spread too thin, more surgeries go wrong

Most major surgeries would not be possible without anaesthesia to render a patient unconscious and pain free and to ensure that their vital functions—including blood pressure, breathing, and heart rate and rhythm—remain stable throughout the procedure. As the demand for such surgical care grows, many clinicians, including anaesthesia care teams, are being asked to take care of more patients, all while maintaining patient safety.

An anaesthesia clinician – a certified registered nurse anaesthetist, certified anaesthesia assistant, anaesthesiology resident or anaesthesiologist – is continuously present in the operating room and delivering important care during every surgery requiring anaesthesia. However, it is not uncommon to have one anaesthesiologist directing the anaesthesia care delivered by other anaesthesia clinicians for multiple surgical cases at a time, according to Sachin Kheterpal, M.D. M.B.A., associate dean for Research Information Technology and professor of Anaesthesiology at Michigan Medicine. 

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 anaesthesiologist increases the risk of death or complications after surgery. 

We now have evidence to support the idea that in some situations, increasing overlapping responsibilities may have some potential downsides that balance the advantages of potential cost savings and access to care

Sachin Kheterpal

Using data from the Multicenter Perioperative Outcomes Group electronic health record registry, the team investigated surgical procedures that involved an anaesthesiologist directing a CRNA or an anaesthesiology resident. This anaesthesia care team model is the most common model used to deliver anaesthesia in the United States. Focusing their analysis on cases with CRNA involvement and minimal anaesthesiology resident involvement, the authors looked at data from more than 570,000 surgical cases at 23 hospitals in the United States between 2010 and 2017. They identified patients with similar demographics and health statuses who underwent surgical cases of various types, including general, gynaecologic, neurologic, otolaryngologic, orthopaedic, urologic and vascular procedures. For each patient, they calculated the average number of concurrent surgeries that were managed by that patient’s anaesthesiologist during the patient’s procedure. They then compared instances where the anaesthesiologist 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 anaesthesiologist directing anaesthesia for one to two overlapping surgeries, directing anaesthesia for two to three or three to four overlapping surgeries led to an increase in the rate of morbidity and mortality. Instances where the anaesthesiologist 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. “Anaesthesiologists have been saying for a long time that covering four operating rooms is possible but should be reserved for situations where we think it’s safe,” said Kheterpal. In fact, U-M Health rarely uses this model. “We now have evidence to support the idea that in some situations, increasing overlapping responsibilities may have some potential downsides that balance the advantages of potential cost savings and access to care.”

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The team notes that the study has several limitations, including the fact that the data analysis was limited to specific types of surgeries and may not reflect outcomes for all surgeries. Michael Burns, M.D., Ph.D., with the Department of Anesthesiology, noted, “While these results are important, they are limited to the data that was available in the study: anaesthesia care team models with a single anaesthesiologist directing up to 4 overlapping surgeries.” 

“Millions of patients receive care from an anaesthesiologist directing more than two overlapping anaesthetics,” noted Kheterpal. “Addressing any differences in care underlying the observed differences in outcome could reduce adverse events for hundreds of thousands of patients.” And while Kheterpal acknowledges that more research is needed to replicate and further explore the differences found in this study, he does have advice for families who may be concerned about the increased risk: “If you are having high risk surgery or you are a medically complex patient, it may be prudent to ask your anaesthesia care team about their typical anaesthesia care processes.” 

Source: University of Michigan


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