The use of pulmonary artery catheter and clinical outcomes in older adults with cardiogenic shock

Background: Evidence is lacking regarding the benefits of pulmonary artery catheter (PAC) for cardiogenic shock (CS). Methods: We analyzed the data on Medicare fee-for-service beneficiaries aged 65-99 admitted with CS from 2016 to 2020 to compare outcomes of patients monitored with versus without PAC. We implemented propensity score matching weight (PSMW) analysis with hospital fixed effects (effectively comparing outcomes within the same hospital) and quasi-experimental instrumental variable (IV) analysis (accounting for potential unmeasured confounders) with the probability of using PAC for CS in the previous year as the instrument. Results: We included 4668 and 78,502 patients admitted with CS, monitored with and without PAC, respectively. We found no evidence that the use of PAC was associated with mortality either in PSMW (adjusted absolute risk difference [aRD], +0.5-percentage-points [pp]; 95 % confidence interval [CI], -1.1 to +2.1) or IV (aRD, -2.5 pp.; 95 % CI, -8.2 to +3.2) analyses. While consistent associations were not observed between the use of PAC and major bleeding and sepsis, the use of PAC was associated with a higher risk of all-bleeding (PSMW: aRD, +1.5 pp.; 95 % CI, +0.1 to +2.9; IV: +13.3 pp.; 95 % CI, +7.7 to +18.8) and longer LOS (PSMW: adjusted mean difference, +1.6 days; 95 % CI, +1.1 to +2.0; IV: +6.9 days; +4.9 to +9.0). Conclusions: We found no evidence that the use of PAC was associated with lower mortality in patients with CS. While high-quality randomized trials are needed, providers should be careful about appropriate settings and indications of the use of PAC for the management of CS.