Objective: 

To associate surgeon-anesthesiologist team familiarity with cardiac surgery outcomes.

Background: 

Team Familiarity (TF), a measure of repeated team member collaborations, has been associated with improved operative efficiency; however, examination of its relationship to clinical outcomes has been limited.

Methods: 

This retrospective cohort study included Medicare beneficiaries undergoing coronary artery bypass grafting (CABG), surgical aortic valve replacement (SAVR), or both (CABG+SAVR) between 01/01/2017-09/30/2018. Team familiarity was defined as the number of shared procedures between the cardiac surgeon and anesthesiologist within six months of each operation. Primary outcomes were 30- and 90-day mortality, composite morbidity, and 30-day mortality or composite morbidity, assessed before and after risk adjustment using multivariable logistic regression.

Results: 

The cohort included 113,020 patients (84,397 CABG; 15,939 SAVR; 12,684 CABG+SAVR). Surgeon-anesthesiologist dyads in the highest [31631 patients, TF median(interquartile range)=8(6,11)] and lowest [44307 patients, TF=0(0,1)] TF terciles were termed familiar and unfamiliar, respectively. The rates of observed outcomes were lower among familiar versus unfamiliar teams: 30-day mortality (2.8% vs. 3.1%, P=0.001), 90-day mortality (4.2% vs. 4.5%, P=0.023), composite morbidity (57.4% vs. 60.6%, P<0.001), and 30-day mortality or composite morbidity (57.9% vs. 61.1%, P<0.001). Familiar teams had lower overall risk-adjusted odds of 30-day mortality or composite morbidity [aOR 0.894(0.868,0.922), P<0.001], and for SAVR significantly lower 30-day mortality [aOR 0.724(0.547,0.959), P=0.024], 90-day mortality [aOR 0.779(0.620,0.978), P=0.031], and 30-day mortality or composite morbidity [aOR 0.856(0.791,0.927), P<0.001].

Conclusions: 

Given its relationship with improved 30-day cardiac surgical outcomes, increasing TF should be considered among strategies to advance patient outcomes.