The pulmonary artery catheter (PAC) is an invasive device that enables real-time monitoring of cardiac physiological parameters, including pulmonary artery pressure, pulmonary capillary wedge pressure, and cardiac output, among others. Although its use is fully embedded in cardiac anesthesia practice, its routine intraoperative use remains controversial. Multiple observational studies have reported conflicting results regarding the clinical benefit of PAC use. In fact, in noncardiac surgery and in intensive care units, its use declined substantially over the past 2 decades after the publication of several clinical trials showing no clinical benefit and a possible increase in device-related complications. More recently, several meta-analyses have suggested that its use may be beneficial in appropriately selected critically ill patients.

Nevertheless, in the setting of cardiac surgery, PAC use remains very common, although reported utilization rates differ substantially across registries, ranging from 7% to 75%. Given these marked discrepancies, this study sought to provide a clearer picture of current PAC utilization rates in a representative sample of cardiac surgery departments at US university hospitals and to assess which factors influence its intraoperative use during cardiac surgery.

This was a cross-sectional observational study based on data from the US MPOG registry. The analysis included data from 145,343 patients who underwent open cardiac surgery between 2016 and 2023 at 53 university hospitals in the United States. The primary objective was to quantify intraoperative PAC use in cardiac surgery and to identify factors associated with its use at the hospital, anesthesiologist, and patient levels. To that end, 2- and 3-level hierarchical models were developed, and their effects were assessed using the median odds ratio (MOR).

PACs were used intraoperatively in 72% of the included patients, although utilization varied significantly across hospitals (0%-98%) and anesthesiologists (0%-100%). Patients in whom a PAC was used had a greater baseline comorbidity burden and were also more likely to have undergone surgery at higher-volume hospitals. PAC utilization also varied according to procedure type, with the lowest rates observed in pulmonic valve procedures and coronary artery bypass surgery, and the highest rates in patients undergoing thoracic organ transplantation.

The 2-level predictive model (fixed effects: patient and hospital; random effect: anesthesiologist) identified anesthesiologist as an independent predictor of PAC use (MOR 7.70; 95% confidence interval 6.82-8.76), as well as heart transplantation (MOR 9.70; 95% confidence interval 7.12-13.30) and lung transplantation (MOR 9.58; 95% confidence interval 7.58-12.15). However, in the 3-level model (fixed effects: patient and hospital; random effects: anesthesiologist nested within hospital), the main source of variability was shown to be the hospital itself (MOR 15.00; 95% confidence interval 8.98-28.32), and the effect previously attributed to the anesthesiologist was actually explained by interhospital differences. Indeed, the effect attributable to anesthesiologists within the same hospital was only 1.70 (95% confidence interval 1.61-1.81). In this model, heart and lung transplantation remained the leading predictors of PAC use.

The authors concluded that PAC use in cardiac surgery remains very common in US university hospitals and that its use is driven far more by hospital-level institutional factors than by patient clinical characteristics or anesthesiologist-related factors.

COMMENTARY:

The findings of this study highlight a well-recognized feature of contemporary clinical practice: the performance of certain procedures and the adoption of certain medical decisions do not always depend on the patient’s clinical profile or the treating physician alone, but are often closely linked to structural factors and resource availability within the hospital or healthcare environment in which care is delivered.

This is clearly illustrated by the fact that the strongest predictor of PAC use was the hospital itself, even after adjustment for other factors such as patient clinical complexity and procedural complexity, reflecting that PAC use is strongly shaped by local institutional practice and staff training.

There was, however, some internal consistency in that PAC use increased with greater procedural difficulty and higher patient clinical complexity.

Altogether, these findings illustrate that, given the lack of strong evidence, clinical trials and studies capable of generating high-quality evidence are still needed to determine whether routine PAC use provides real benefit and, if so, which patients are most likely to benefit from it.

REFERENCE:

MacKay EJ, Zhang B, Beaty JM, Devine KA, O’Reilly-Shah V, Mathis MR, Szeto WY, Groeneveld PW, Augoustides JG. Practice Pattern Variability in the Use of Pulmonary Arterial Catheters in Cardiac Surgery. J Cardiothorac Vasc Anesth. 2025 Dec;39(12):3268-3276. doi: 10.1053/j.jvca.2025.08.013.