Effects of resident involvement on complication rates after laparoscopic gastric bypass

Abstract

Background: Although resident involvement has been shown to be safe for most procedures, the impact of residents on outcomes after complex laparoscopic procedures is not well understood. We sought to examine the impact of resident involvement on outcomes after bariatric surgery using a population-based clinical registry.

Study design: We analyzed 17,057 patients who underwent a primary laparoscopic gastric bypass in the 35-hospital Michigan Bariatric Surgery Collaborative from July 2006 to August 2012. Resident involvement was characterized at the surgeon level. Using hierarchical logistic regression, we examined the influence of resident involvement on 30-day complications, accounting for patient characteristics as well as hospital and surgeon case volume. To evaluate potential mediating factors for specific complications, we also adjusted for operative duration.

Results: Risk-adjusted 30-day complication rates with and without residents were 13.0% and 8.5%, respectively (p < 0.01). Resident involvement was independently associated with wound infection (odds ratio [OR] = 2.06; 95% CI, 1.24-3.43) and venous thromboembolism (OR = 2.01; 95% CI, 1.19-3.40), but not with any other medical or surgical complications. Operative duration was longer with resident involvement (median duration with residents 129 minutes vs 88 minutes without; p < 0.01). After adjusting for operative duration, resident involvement was still independently associated with wound infection (OR = 1.67; 95% CI, 1.01-2.76), but not venous thromboembolism (OR = 1.73; 95% CI, 0.99-3.04).

Conclusions: Resident involvement in laparoscopic gastric bypass is independently associated with wound infections and venous thromboembolism. The effect appears to be mediated in part by longer operative times. These findings highlight the importance of strategies to assess and improve resident technical proficiency outside the operating room.

Figure 1

Risk-adjusted 30-day complication rates by resident involvement. Dark gray bar, no residents; light gray bar, resident involvement. *p < 0.05 compared with risk-adjusted complication rate without resident involvement. Variables included in risk-adjustment model: renal insufficiency, non-insulin–requiring diabetes, earlier venous thromboembolism, mobility limitations, age older than 50 years, pulmonary disease, male sex, psychological disease, earlier upper abdominal wall hernia repair, body mass index quintile, current smoking status, cardiovascular disease, presence of >4 comorbidities as a dichotomous variable, surgeon procedure volume tercile, and hospital procedure volume (<200 or >200 cases/y).

Figure 2

Risk-adjusted surgical and medical complication rates by resident involvement. (A) Surgical complications; (B) medical complications. Dark gray bar, no residents; light gray bar, resident involvement. *p < 0.05 compared with risk-adjusted complication rate without resident involvement. Variables included in risk-adjustment model: renal insufficiency, non-insulin–requiring diabetes, earlier venous thromboembolism, mobility limitations, age older than 50 years, pulmonary disease, male sex, psychological disease, earlier upper abdominal wall hernia repair, body mass index quintile, current smoking status, cardiovascular disease, presence of >4 comorbidities as a dichotomous variable, surgeon procedure volume tercile, and hospital procedure volume (<200 or >200 cases/y).