HEMODYNAMIC ASSESSMENT IN MANAGING THE CRITICALLY ILL - IS PHYSICIAN CONFIDENCE WARRANTED

Prior to right-heart catheterization of 846 patients, 198 study physic ians estimated values of pulmonary capillary wedge pressure (WP), card iac index (CI), and systemic vascular resistance index (VRI). The phys icians also expressed their confidence in these estimates. Actual valu es of WP, CI, and VRI as determined by catheterization enabled the aut hors to evaluate the quality of the physicians' judgments. The discrim ination of the judgments was modest; areas under the ROC curves for WP , CI, and VRI were 0.724, 0.681, and 0.656, respectively. Calculated u sing clinically relevant cutoff values, sensitivities were 64%, 50%, a nd 64%, and specificities were 71%, 75%, and 63%, respectively. Calibr ation of the estimates of WP, CI, and VRI was also modest; physicians tended to overestimate low values and underestimate high values. Physi cians were generally confident of their estimates, but there was no re lation between confidence and accuracy. Experienced physicians were no more accurate than less experienced ones, although they were signific antly more confident. The authors conclude that physicians should not use their levels of confidence in their subjective estimates of cardia c function in deciding whether to base therapy on these estimates.