Time-varying analysis of readmission and mortality during the first year after pneumonectomy.

OBJECTIVES: Mortality rates of 5% to 10% after pneumonectomy have remained constant during the last decade. To understand the patterns of outcomes after pneumonectomy, we investigated the time-varying risks of readmission and death during the first postoperative year and examined the contributions of specific causes to these patterns over time.
METHODS: We retrospectively reviewed all pneumonectomies for lung cancer at our institution from 2000 to 2018. The time-varying instantaneous risk of all-cause readmission and mortality up to 1 year after pneumonectomy was estimated using parametric analyses and was repeated for each primary cause of readmission (oncologic, infectious, pulmonary, cardiac, or other) and death (oncologic or nononcologic).
RESULTS: In our cohort of 355 patients who underwent pneumonectomy, risk of readmission was highest immediately after discharge and was halved by 14 days. This risk reached a nadir and remained constant from 4 to 8 months, after which it gradually increased. Pulmonary causes accounted for most readmissions within 90 days, after which oncologic causes predominated. Likewise, the overall risk of death was highest immediately after surgery, was halved by 7 days, reached a nadir at 90 days, and then increased throughout the remainder of the first year. All deaths during the first 90 days after surgery were due to nononcologic causes.
CONCLUSIONS: Nononcologic causes of readmission and death predominate in the first 90 days after pneumonectomy, after which oncologic causes prevail. We also identify specific causes that pose the highest risk of readmission immediately after discharge. Efforts are warranted to define the effects of specific causes of readmission on overall mortality after pneumonectomy.