Impact of preoperative anemia on postoperative outcomes in patients undergoing video-assisted thoracoscopic surgery: a multi-institutional retrospective study.

BACKGROUND

Video-assisted thoracoscopic surgery (VATS) involves unique physiological challenges, including single-lung ventilation, that may amplify the effects of reduced oxygen-carrying capacity in anemic patients. Despite the minimally invasive nature of VATS, the specific impact of preoperative anemia on outcomes following these procedures remains inadequately characterized.

METHODS

We conducted a multi-institutional retrospective cohort study using TriNetX research network data (2010-2024). Adults undergoing VATS with preoperative hemoglobin measurements were included. The anemia group (hemoglobin 8-12 g/dL) was compared to the control group (hemoglobin ≥12 g/dL) using 1:1 propensity score matching.

RESULTS

After matching, 8,346 pairs of patients were analyzed. Patients with preoperative anemia had significantly higher 30-day mortality (odds ratio [OR] 3.20, 95% confidence interval [CI] 2.33-4.39, P<0.0001) (primary outcome), intensive care unit admission (OR 1.46, 95% CI 1.27-1.67, P<0.0001), acute kidney injury (AKI) (OR 1.92, 95% CI 1.58-2.32, P<0.0001), pneumonia/respiratory failure (OR 1.73, 95% CI 1.53-1.95, P<0.0001), and sepsis (OR 1.79, 95% CI 1.36-2.36, P<0.0001). These associations remained consistent in sensitivity analyses restricted to academic medical centers, patients without blood transfusions, and those with stable hemoglobin levels throughout the perioperative period. Sex-specific analyses revealed higher risks of respiratory complications, AKI, sepsis, and deep vein thrombosis in males, while females with anemia demonstrated higher mortality risk. Even mild anemia was associated with significantly increased complications.

CONCLUSIONS

Preoperative anemia is strongly associated with adverse outcomes following VATS, with an over threefold increased mortality risk. These findings highlight the importance of preoperative anemia assessment and management in patients undergoing VATS.