The effects of advanced monitoring on hemodynamic management in critically ill patients: a pre and post questionnaire study

In critically ill patients, many decisions depend on accurate assessment of the hemodynamic status. We evaluated the accuracy of physicians' conventional hemodynamic assessment and the impact that additional advanced monitoring had on therapeutic decisions. Physicians from seven European countries filled in a questionnaire in patients in whom advanced hemodynamic monitoring using transpulmonary thermodilution (PiCCO system; Pulsion Medical Systems SE, Feldkirchen, Germany) was going to be initialized as part of routine care. The collected information included the currently proposed therapeutic intervention(s) and a prediction of the expected transpulmonary thermodilution-derived variables. After transpulmonary thermodilution measurements, physicians recorded any changes that were eventually made in the original therapeutic plan. A total of 315 questionnaires pertaining to 206 patients were completed. The mean difference (±standard deviation; 95 % limits of agreement) between estimated and measured hemodynamic variables was -1.54 (±2.16; -5.77 to 2.69) L/min for the cardiac output (CO), -74 (±235; -536 to 387) mL/m(2) for the global end-diastolic volume index (GEDVI), and -0.5 (±5.2; -10.6 to 9.7) mL/kg for the extravascular lung water index (EVLWI). The percentage error for the CO, GEDVI, and EVLWI was 66, 64, and 95 %, respectively. In 54 % of cases physicians underestimated the actual CO by more than 20 %. The information provided by the additional advanced monitoring led 33, 22, 22, and 13 % of physicians to change their decisions about fluids, inotropes, vasoconstrictors, and diuretics, respectively. The limited clinical ability of physicians to correctly assess the hemodynamic status, and the significant impact that more physiological information has on major therapeutic decisions, support the use of advanced hemodynamic monitoring in critically ill patients.