The Cost of the "July Effect" in Microsurgery.

The existence of the "July effect," or the idea that the new academic year intrinsically has an increased complication rate is evaluated in microsurgical free tissue transfer procedures. The National Surgical Quality Improvement Program registry was queried for all free flap procedures performed between 2005 and 2016 (n = 3405). Cases were grouped as having occurred in the first academic quarter (Q1: July 1-September 30) or fourth quarter (Q4: April 1-June 30). Demographical data and complications were compared using univariate χ analysis, multivariate logistic regression was used to control for confounding variables, and inpatient stay and operating cost estimates were created. Of a total of 1722 cases, 905 were performed in the first academic quarter and 817 were performed in the fourth academic quarter. There was no significant difference between Q1 and Q4 in readmission rate (P = 0.378) or reoperation rate (P = 0.730). Patients in Q1 had significantly longer operative times (P = 0.001) and length of stay (P = 0.002) compared with those in Q4. In addition, cost of inpatient stay and operating costs associated with each free flap were significantly increased in Q1 compared with Q4 (P = 0.029; P = 0.001). The total cost per quarter for free flaps was also significantly more expensive in Q1 vs Q4, with the highest average difference in cost of $350,010.64 (P = 0.001). Having surgery early in the academic year does not put patients at any increased risk for major complications but is associated with increased operating time, length of stay, and total cost.