Pulmonary Hypertension and the Risk of 30-day Postoperative Pulmonary Complications after Gastrointestinal Surgical or Endoscopic Procedures: A Retrospective Propensity Score Weighted Cohort Analysis.

Background: Pulmonary hypertension (PH) patients are at higher risk of postoperative complications. We analyzed the association of PH with 30-day postoperative pulmonary complications (PPC). Methods: A single-center propensity score overlap weighting (OW) retrospective cohort study of 164 patients with mean pulmonary artery pressure (mPAP) of >20 mmHg within 24 months of procedure and a control cohort (N=1981), undergoing elective inpatient abdominal surgery or endoscopic procedures under general anesthesia. The primary outcome was PPC, and the secondary outcomes were PPC sub-composites; respiratory failure (RF), pneumonia (PNA), aspiration pneumonia/pneumonitis (ASP), pulmonary embolism (PE), length of stay (LOS), and 30-day mortality. Results: PPC was higher in the PH cohort (29.9% vs. 11.2%, p<0.001). When sub-composites were analyzed, higher rates of RF (19.3% vs. 6.6%, p<0.001) and PNA (11.2% vs. 5.7%, p=0.01) were observed. After OW, PH was still associated with higher PPC [RR 1.66, 95% CI (1.05 - 2.71), p=0.036] and increased LOS (median 8.0 days vs. 4.9 days) but not 30-day mortality. Sub-cohort analysis showed no difference in PPC between pre- and post-capillary PH patients. Conclusions: After covariate balancing, PH was associated with a higher risk for PPC and pro-longed LOS. This elevated PPC risk should be considered during preoperative risk assessment.