Pulmonary Risk Stratification in Open Thoracoabdominal Aortic Aneurysm Repair.

Background/

Objectives

The aim of this study was to assess whether preoperative pulmonary function testing (PFT) is related to postoperative complications after open thoracoabdominal aortic aneurysm (TAAA) repair.

Methods

This study was conducted as a retrospective cohort analysis of 205 patients undergoing open TAAA repair (2006-2024) with preoperative spirometry and body plethysmography with at least one value available. Patients were classified by ventilation patterns: obstructive (n = 85, 45.2%), restrictive (n = 26, 14.1%), and hyperinflation (n = 56, 30.3%). Primary endpoints included in-hospital mortality, pulmonary complications (pneumonia, ARDS), and multi-organ outcomes. Associations were analyzed using chi-square and Spearman correlation tests and multivariable linear regression adjusted for age, smoking status, COPD, emergency operation, and time period.

Results

Postoperative pulmonary complications occurred in 126 patients (61.5%), including pneumonia (46.8%) and ARDS (15.1%). Reduced vital capacity and FEV1 expressed as a percentage of the lower limit of normal (%LLN) were related to postoperative pneumonia (p = 0.031 and p = 0.003) and ARDS (p = 0.038). Both obstructive and restrictive ventilation patterns were related to acute kidney injury after surgery (all KDIGO stage) (p = 0.044 and p = 0.043, respectively). Hyperinflation was related to atrial fibrillation (p = 0.039) and stroke (p = 0.034). FEV1 < 2.0 L was related to increased mortality risk (p = 0.037), and FEV1 < 1.5 L predicted acute kidney injury (p = 0.017), spinal cord ischemia (p = 0.035), and mortality (p = 0.023). Prolonged mechanical ventilation correlated with reduced preoperative lung function (VC %LLN ρ = -0.288, p = 0.002; FEV1 %LLN ρ = -0.286, p = 0.001). During median follow-up of 6.35 years, patients in the highest FEV1 quartile demonstrated substantially reduced long-term mortality (HR 0.27, 95% CI 0.10-0.73, p = 0.01). These associations between lower FEV1 and VC (expressed as %LLN) with pneumonia, ARDS, in-hospital mortality, and prolonged ventilation remained significant after multivariable analysis.

Conclusions

Preoperative pulmonary function assessment may help identify TAAA patients at increased risk of postoperative complications and mortality. Combining percentage-predicted spirometry, ventilation patterns, and hyperinflation markers may support individualized treatment selection, prehabilitation, and perioperative monitoring based on each patient's specific risk profile.