Questionable benefit of the pulmonary artery catheter after cardiac surgery in high-risk patients

Objective The aim of this study was to determine the effect of pulmonary artery catheterization on clinical outcomes after cardiac surgery in higher-risk patients. Design Retrospective national database analysis. Setting U.S. hospitals. Participants A weighted sample of 2,063,337 patients undergoing cardiac surgery identified from the Nationwide Inpatient Sample (NIS) from January 1, 2000 to December 31, 2010. Interventions Pulmonary artery catheterization. Measurements and Main Results Compared to patients who did not receive a pulmonary artery catheter, those who did on the whole were on average slightly older (66.6±11.9 years v 65.5±12.8 years, p<0.001), more likely to have pulmonary hypertension (7.5% v 5.1%, p<0.001), chronic obstructive pulmonary disease (24.6% v 20.7%, p<0.001), obesity (15.0% v 13.1%, p<0.001), and chronic renal failure (10.9% v 9.2%, p<0.001). In multivariate analysis, the risk of operative mortality in patients who underwent pulmonary artery catheterization was significantly higher than in those who did not (4.6% v 3.1%, p<0.001), adjusted OR 1.34 (95% CI 1.26-1.43, p<0.001). In propensity matched subgroup analysis operative mortality risk was higher in octogenarian patients (OR 1.24, p = 0.24), and patients with congestive heart failure (OR 1.39, p = 0.023) who underwent pulmonary artery catheterization. No significant difference in operative mortality was observed in low-risk patients according to whether or not they underwent pulmonary artery catheterization. The incidence of prolonged mechanical ventilation and length of stay>30 days was higher in patients who underwent pulmonary artery catheterization in all subgroups. Conclusions In contemporary practice pulmonary artery catheters do not appear to be associated with reductions in operative mortality or morbidity and are associated with increases in duration of ventilation and length of stay in the intensive care unit.