Is Elective Nighttime Operation Associated With Adverse Outcomes? Analysis in Immediate Tissue Expander–Based Breast Reconstruction

Background: Despite the long-standing presumption that nighttime surgery could affect adverse outcomes, its association independent of patient’s general condition and disease severity remains unclear. We hypothesized that conducting elective surgery for subjects with good physical status at nighttime was not associated with increased risks of postoperative complications and aimed to examine it in tissue-expander-insertion (TEI) operation for breast reconstruction. Method: Patients who underwent immediate unilateral TEI-based breast reconstruction between 2014 and 2019 were enrolled. They were categorized into 3 groups based on the starting time of the TEI operation: 8 AM to 6 PM (group 1), 6 PM to 8 PM (group 2), and after 8 PM (group 3). The postoperative complication rates were compared among the groups. The independent associations of each variable, including the operation starting time and adverse outcomes, were analyzed. Results: In total, 1458 patients were analyzed, including 970 in group 1, 358 in group 2, and 130 in group 3. The groups showed similar baseline characteristics regarding comorbidities and the American Society of Anesthesiologists classification. Compared with group 1, group 3 was associated with significantly increased rates of overall complications including infection, reoperation, and premature removal of the tissue expander. These differences retained influences in the multivariable analyses. Group 3 showed a significantly longer hospitalization period than the other 2 groups. The complication rates did not differ between groups 1 and 2. Conclusions: Conducting TEI operation at nighttime seems to be associated with increased risks of adverse postoperative outcomes compared with conducting it during regular working hours.