Abstract 19052: Preoperative Non-invasive RVSP Correlates Poorly with Invasively Measured Pulmonary Artery Systolic Pressure During General Anesthesia
Introduction: Pulmonary hypertension (PH) is an independent marker of surgical morbidity. Right ventricular systolic pressure (RVSP) measured by transthoracic echocardiography (TTE), correlates poorly with pulmonary artery systolic pressure (PASP) measured by right heart catheterization, especially in PH. The correlation between TTE derived RVSP and intraoperative PASP, while under general anesthesia, is not known. In this study, the association between preoperative RVSP and intraoperative PASP was tested.
Methods: All consenting adult surgical patients requiring intraoperative pulmonary pressure monitoring in a 2 year period were retrospectively identified. Patients who had TTE estimated RVSP ≥ 40 mmHg, measured within a week prior to the index surgery, were included. RVSP was calculated from tricuspid regurgitant velocity using the modified Bernoulli equation. For intraoperative PASP, the median of the first 10 minutes after PAC placement was used. CVP, arterial systolic pressure, minimum alveolar concentration of anesthetic (MAC) and basic demographic data were also collected. Agreement between RVSP and PASP was tested using the concordance correlation coefficient. Multivariate linear regression and Bland-Altman plot were used to further refine the analysis.
Results: 129 patients met inclusion criteria. Median age (IQR) was 73 (62 - 79) years; TTE was performed a median (IQR) of 2 (1 - 3) days prior to surgery; mean (SD) RVSP was 56.1 (±12.4) mmHg and mean (SD) PASP was 42.1 (±14.9) mmHg. Concordance correlation coefficient between RVSP and PASP was only 0.13 (95% CI 0.02 - 0.24). On multivariate linear regression, PASP was significantly associated with RVSP and CVP (p < 0.01), but not anesthetic MAC, age or proximity of measurements. Bland-Altman bias was -13.9 mmHg; 95% limits of agreement were -48.0 to +20.1 mmHg.
Conclusion: Preoperative RVSP measured by TTE correlates poorly with intraoperative PASP measured by PAC during general anesthesia.
- © 2012 by American Heart Association, Inc.