Early vs Late/No PAC Use in Cardiogenic Shock Patients on ECMO: Mortality and Renal Outcome

Introduction: Cardiogenic shock (CS) carries high in-hospital mortality. The optimal timing of pulmonary artery catheter (PAC) placement in patients on extracorporeal membrane oxygenation (ECMO) is unclear. This study examines whether early PAC placement (before or within 24 hours of ECMO) is associated with higher continuous renal replacement therapy (CRRT) initiation and improved mortality and renal outcomes compared to late or no PAC use.


Methods: This retrospective cohort study included adults with CS who received ECMO at UPMC Harrisburg (Jan 2020–Jun 2024). Data on demographics, comorbidities, labs, and outcomes were extracted from electronic records. Patients were grouped by PAC timing: early (≤24h of ECMO) vs. late/no PAC. Charlson Comorbidity Index and SOFA scores assessed baseline risk. Renal deterioration was defined as ≥2× baseline creatinine and/or CRRT initiation. Multivariable logistic regression analyzed associations between PAC timing and in-hospital mortality, adjusting for confounders.


Results: Of the 77 patients studied, 15 (19.5%) received early PAC placement, while 62 (80.5%) underwent late or no PAC placement. Compared to the late/no PAC group, those receiving early PAC were younger and more likely to be male, with similar Charlson Comorbidity Index and SOFA scores. Early PAC placement was associated with higher rates of CRRT initiation (53.3% vs. 35.5%), whereas rates of creatinine-based renal deterioration were comparable between groups (26.7% vs. 24.2%). Crude in-hospital mortality was lower among early PAC recipients (33.3% vs. 48.4%). Adjustment for comorbidity burden and illness severity (Charlson Index, SOFA) accentuated the mortality benefit associated with early PAC (unadjusted OR 0.91, 95% CI 0.76–1.09; adjusted OR 0.84, 95% CI 0.70–1.02). After further adjustment for CRRT use, early PAC placement remained significantly associated with reduced in-hospital mortality (adjusted OR 0.80, 95% CI 0.65–0.98).


Conclusions: Early PAC placement in CS patients on ECMO was associated with a trend toward lower in-hospital mortality, possibly due to earlier hemodynamic optimization and CRRT initiation. However, given the small sample and retrospective design, findings are preliminary. Larger prospective studies are needed to confirm clinical benefit and inform practice.