Fragmentation of practice: The adverse effect of surgeons moving around

Whether surgical team familiarity is associated with improved postoperative outcomes remains unknown. We sought to characterize the impact of fragmented surgical practice on the likelihood that a patient would experience a textbook outcome, which is a validated patient-centric composite outcome representing an "ideal" postoperative outcome.

Medicare beneficiaries aged 65 and older who underwent elective inpatient abdominal aortic aneurysm repair, coronary artery bypass graft, cholecystectomy, colectomy, or lung resection were identified. Rate of fragmented practice was calculated based on the total number of surgical procedures of interest performed over the study period (2013-2017) divided by the number of different hospitals in which the surgeon operated. Surgeons were categorized into "low," "average," "above average," or "high" rate of fragmented practice categories using an unsupervised machine learning technique known k-medians cluster analysis.

Among 546,422 Medicare beneficiaries who underwent an elective surgical procedure of interest (coronary artery bypass graft: n = 156,384, 28.6%; lung resection: n = 83,164, 15.2%; abdominal aortic aneurysm: n = 112,578, 20.6%; cholecystectomy: n = 42,955, 7.9%; colectomy: n = 151,341, 27.7%), median patient age was 74 years (interquartile range: 69-80), and most patients were male (n = 319,153, 58.4%). Machine learning identified 3 cutoffs to categorize rate of fragmented practice: 2.8%, 5.6%, and 10.6%. Overall, the majority of surgical procedures were performed by surgeons with a low rate of fragmented practice (n = 382,504, 70.0%); other surgical procedures were performed by surgeons with average (n = 109,141, 20.0%), above average (n = 44,249, 8.1%), or high (n = 10,528, 1.9%) rate of fragmented practice. On multivariable analyses, after controlling for patient demographics, individual surgeon volume, procedure type, and a random effect for hospital, patients who underwent a surgical procedure by a high versus low rate of fragmented practice surgeon had lower odds to achieve a postoperative textbook outcome (odds ratio 0.71, 95% confidence interval 0.77-0.84). Patients who underwent a procedure by a high rate of fragmented practice surgeon also had increased odds of a perioperative complication (odds ratio 1.30, 95% confidence interval: 1.23-1.37), extended length of stay (odds ratio 1.17, 95% confidence interval: 1.11-1.24), 90-day readmission (odds ratio 1.17, 95% confidence interval: 1.11-1.23), and 90-day mortality (odds ratio 1.29, 95% confidence interval: 1.17-1.42) (all P < .05).

Patients undergoing a surgical procedure by a surgeon with a high rate of fragmented practice had lower odds of achieving an optimal postoperative textbook outcome. Surgical team familiarity, measured by a surgeon rate of fragmented practice, may represent a modifiable mechanism to improve surgical outcomes.