Preoperative anemia displays a dose-dependent effect on complications in head and neck oncologic surgery

Introduction: Anemia's effect on head and neck surgical complications is unknown. Methods: Head and neck cancer operations were acquired from the 2006 to 2013 American College of Surgeons National Surgical Quality Improvement Program databases. Anemia was defined as <39% or <36% hematocrit in men and women, respectively. Multivariable logistic regression analyses were performed. Results: Major head and neck surgery patients had a 44.2% anemia incidence (n = 527 of 1193). Anemic patients had increased complication rates (27.1%) and mortality (2.1%) vs non-anemic patients at 19.8% (P =.003) and 0.5% (P =.009), respectively. There was a significant difference in morbidity odds with hematocrit >27% (odds ratio [OR] = 1.09) vs <27% (OR = 4.22). Complication odds were further increased with hematocrit between 24% and 27% (OR = 8.94). There were increased rates of wound dehiscence (6.6% vs 2.7%, P <.001), pneumonia (8.5% vs 4.7%, P =.006), and myocardial infarction (1.7% vs 0.3%, P =.01) in anemic vs non-anemic patients. Conclusion: Anemia was associated with increased morbidity at hematocrit <27%. An inverse dose-dependent effect of decreasing hematocrit was observed for overall morbidity.