Monitoring changes in individual surgeon’s workloads using anesthesia data

Association of surgeons' gender with elective surgical lists in the State of Florida is explained by differences in mean operative caseloads

BACKGROUND

A recent publication reported that at three hospitals within one academic health system, female surgeons received less surgical block time than male surgeons, suggesting potential gender-based bias in operating room scheduling. We examined this observation's generalizability.

METHODS

Our cross-sectional retrospective cohort study of State of Florida administrative data included all 4,176,551 ambulatory procedural encounters and inpatient elective surgical cases performed January 2017 through December 2019 by 8875 surgeons (1830 female) at all 609 non-federal hospitals and ambulatory surgery centers. There were 1,509,190 lists of cases (i.e., combinations of the same surgeon, facility, and date). Logistic regression adjusted for covariables of decile of surgeon's quarterly cases, surgeon's specialty, quarter, and facility.

RESULTS

Selecting randomly a male and a female surgeons' quarter, for 66% of selections, the male surgeon performed more cases (P < .0001). Without adjustment for quarterly caseloads, lists comprised one case for 44.2% of male and 54.6% of female surgeons (difference 10.4%, P < .0001). A similar result held for lists with one or two cases (difference 9.1%, P < .0001). However, incorporating quarterly operative caseloads, the direction of the observed difference between male and female surgeons was reversed both for case lists with one (-2.1%, P = .03) or one or two cases (-1.8%, P = .05).

CONCLUSIONS

Our results confirm the aforementioned single university health system results but show that the differences between male and female surgeons in their lists were not due to systematic bias in operating room scheduling (e.g., completing three brief elective cases in a week on three different workdays) but in their total case numbers. The finding that surgeons performing lists comprising a single case were more often female than male provides a previously unrecognized reason why operating room managers should help facilitate the workload of surgeons performing only one case on operative (anesthesia) workdays.

Benchmarking Surgeons’ Gender and Year of Medical School Graduation Associated With Monthly Operative Workdays for Multispecialty Groups

Background

Female surgeons reportedly receive less surgical block time and fewer procedural referrals than male surgeons. In this study, we compared operative days between female and male surgeons throughout Florida. Our objective was to facilitate benchmarking by multispecialty groups, both the endpoint to use for statistically reliable results and expected differences.

Methodology

The historical cohort study included all 4,060,070 ambulatory procedural encounters and inpatient elective surgical states performed between January 2017 and December 2019 by 8,472 surgeons at 609 facilities. Surgeons’ gender, year of medical school graduation, and surgical specialty were obtained from their National Provider Identifiers.

Results

Female surgeons operated an average of 1.0 fewer days per month than matched male surgeons (99% confidence interval 0.8 to 1.2 fewer days, P < 0.0001). The mean differences were 0.8 to 1.4 fewer days per month among each of the five quintiles of years of graduation from medical school (all P ≤ 0.0050). Results were comparable when repeated using the number of monthly cases the surgeons performed.

Conclusions

An average difference of ≤1.4 days per month is a conservative estimate for the current status quo of the workload difference in Florida. Suppose that a group’s female surgeons average more than two fewer operative days per month than the group’s male surgeons of the same specialty. Such a large average difference would call for investigation of what might reflect systematic bias. While such a difference may reflect good flexibility of the organization, it may show a lack of responsiveness (e.g., fewer referrals of procedural patients to female surgeons or bias when apportioning allocated operating room time).

More surgery in December among US patients with commercial insurance is offset by unrelated but lesser surgery among patients with Medicare insurance

Study Objective

Evaluate whether there is more surgery (in the US State of Florida) at the end of the year, specifically among patients with commercial insurance.

Design

Observational cohort study.

Setting

The 712 facilities in Florida that performed inpatient or outpatient elective surgery from January 2010 through December 2019.

Results

Among patients with commercial insurance, December had more cases than November (1.108 [1.092–1.125]) or January (1.257 [1.229–1.286]). In contrast, among patients with Medicare insurance (traditional or managed care), December had fewer cases than November (ratio 0.917 [99% confidence interval 0.904–0.930]) or January (0.823 [0.807–0.839]) of the same year. Summing among all cases, December did not have more cases than November (ratio 1.003 [0.992–1.014]) or January (0.998 [0.984–1.013]). Comparing December versus November (January) ratios for cases among patients with commercial insurance to the corresponding ratios for cases among patients with Medicare, years with more commercial insurance cases had more Medicare cases (Spearman rank correlation +0.36 [+0.25], both p < 0.0001).

Conclusions

In the US State of Florida, although some surgeons' procedural workloads may have seasonal variation if they care mostly for patients with one category of insurance, surgical facilities with patients undergoing many procedures will have less variability. Importantly, more commercial insurance cases were not causing Medicare cases to be postponed or vice‐versa, providing mechanistic explanation for why forecasts of surgical demand can reasonably be treated as the sum of the independent workloads among many surgeons.

In US State of Florida, patients with commercial insurance had more surgery in December

Patients with US Medicare insurance had less surgery in December than other months

Years with more commercial insurance cases in December had more US Medicare cases too

Implication for surgical suites: busier months for some patient groups balanced by less busy for others

Most surgeons' daily elective lists in Florida comprise only 1 or 2 elective cases, making percent utilization unreliable for planning individual surgeons' block time

STUDY OBJECTIVE

Operating room (OR) utilization has been shown in multiple studies to be an inappropriate metric for planning OR time for individual surgeons. Among surgeons with low daily caseloads, percentage utilization cannot be measured accurately because confidence limits are extremely wide. In Iowa, a largely rural state, most surgeons performed only 1 or 2 elective cases on their OR days. To assess generalizability, we analyzed Florida, a state with many high-population density areas.

DESIGN

Observational cohort study.

SETTING

The 602 facilities in Florida that performed inpatient or outpatient elective surgery from January 2010 through December 2019.

SUBJECTS

The providers licensed to perform surgery in Florida (physician, oral surgeons, dentists, and podiatrists) were identified by their national provider number. Hospitals were deidentified before analysis.

MEASUREMENTS

The primary endpoint was the mean among facilities in percentages of surgeon-day combinations ("lists") containing 1 or 2 cases. Proportions were calculated using Freeman-Tukey transformation and the harmonic mean of the number of lists at each facility. Comparison to "most" (>50%) used Student's two-sided one-group t-test.

MAIN RESULTS

Averaging among hospitals, most surgeons' lists included 1 or 2 cases (64.4%; 99% confidence interval [CI] 61.3%-67.4%) P < 0.00001). Many lists had 1 case (44.2%, 99% CI 41.2%-47.2%). Nearly all (96.7%) surgeons operated at just one hospital on their OR days.

CONCLUSIONS

Most surgeons' lists of elective surgical cases comprised 1 or 2 cases in the largely urban state of Florida, as previously found in the largely rural state of Iowa. Results were insensitive to organizational size or county population. Thus, our finding is generalizable in the United States. Consequently, neither adjusted nor raw utilization should be used solely when allocating OR time to individual surgeons. Anesthesia and nursing coverage of cases can be based on maximizing the efficiency of use of OR time.

Appropriate operating room time allocations and half-day block time for low caseload proceduralists, including anesthesiologist pain medicine physicians in the State of Florida

STUDY OBJECTIVE

We analyzed University of Iowa operating room data to estimate whether it would be economically rational to allocate, every two weeks, an operating room to anesthesiology pain medicine physicians or a half-day session to individual proceduralists. We investigated the generalizability of the results by studying anesthesiologist pain medicine physicians working at all hospitals and ambulatory surgery centers in the State of Florida.

DESIGN

Observational, cohort study of spinal neuromodulation procedures.

MEASUREMENTS

Hours of daily operating room time and cases by anesthesiologist pain medicine physicians at the University of Iowa, and in Florida in 2018. For each two-week period, we calculated the difference in hours between (1) the under-utilized time from allocating 8 h and (2) time-and-a-half times the over-utilized time from no allocated time.

MAIN RESULTS

The mean greater cost from allocating 8 h vs 0 h equaled 3.89 h, significantly >0 (P = 0.0001, N = 77 periods). Sample mean activities were 0.79 cases and 1.64 h, <2.00 cases and 4.00 h, respectively (both P < 0.0001). Thus, no allocated time or block time should be planned. At least 76.6% (95% lower confidence limit) of Florida surgical facilities performing ≥1 neuromodulation procedures averaged <1.08 cases per two weeks. At least 89.6% of the facilities averaged <2 cases per two weeks. At least 88.8% of combinations of anesthesiologist and facility in Florida averaged fewer cases per two weeks than anesthesiologist proceduralists at the University of Iowa. At least 96.5% of the proceduralists averaged <2 cases per two weeks at each facility where they operated.

CONCLUSIONS

Among anesthesiologist proceduralists in Florida using operating room time for neurostimulator procedures, most perform too few cases weekly for the economically appropriate planning of block time. Few Florida facilities would have enough cases, even potentially, to warrant allocating operating room time.