Physical examination, central venous pressure, and chest radiography for the prediction of transpulmonary thermodilution-derived hemodynamic parameters in critically ill patients: a prospective trial

PURPOSE: Physical examination, assessment of central venous pressure (CVP) and chest radiography are diagnostic tools for estimation of volume status in intensive care unit (ICU) patients. Passive leg raising (PLR) is a test to estimate fluid responsiveness. Transpulmonary thermodilution (TPTD) is established for measurement of cardiac index (CI), global end-diastolic volume index (GEDVI), and extravascular lung water index (EVLWI). This study compares the estimation of volume status using physical examination, CVP, chest radiography, PLR, and TPTD.

MATERIALS AND METHODS: This study was a prospective trial. Seventy-one patients in a medical ICU were studied. Interventions were as follows: physical examination by 2 independent examiners. CVP was measured. TPTD was performed. In 2 patient subgroups PLR and chest radiography was performed. Comparison of clinical and x-ray-based estimation of volume status, CVP, PLR, and TPTD variables was performed.

RESULTS: Estimation of volume status based on physical examination showed a poor interobserver agreement between the examiners. There was no significant correlation between physical examination-based estimation of volume status and CVP or TPTD-derived GEDVI. There was no significant correlation between CVP and GEDVI, EVLWI or CI. PLR did not indicate fluid responsiveness. Radiographically estimated and TPTD-GEDVI/EVLWI values were significantly different.

CONCLUSIONS: In ICU patients, assessment of volume status remains difficult. Physical examination, CVP, and portable radiography do not correlate with TPTD assessment of volume status, preload, or pulmonary hydration.