Impact of point-of-care B-type natriuretic peptide (BNP) measurement on medical decision-making for older Emergency Department patients with dyspnea

Measurement of B-type natriuretic peptide (BNP) has been shown to aid in the Emergency Department (ED) diagnosis of heart failure. We sought to determine how point-of-care BNP measurement influences real-world medical decision-making. Using a commercially available, point-of-care assay, BNP levels were measured in a convenience sample of ED patients over the age of 55 years who complained of dyspnea. Blinded to BNP results, emergency physicians were asked to formulate a differential diagnosis and management plan for each patient. Immediately thereafter, BNP results were disclosed and the physicians were asked what (if any) decisions they would change. With physicians blinded to BNP results, 24 of 88 patients (27%) were given a primary diagnosis of heart failure, and 18 patients (20%) were given a secondary or alternative diagnosis of heart failure. For the former group, disclosure of BNP results resulted in no changes in diagnosis or management. For the latter group, disclosure of BNP results caused heart failure to become the primary diagnosis in 4 patients (22%), and led to five changes in medical management. For the 46 patients initially given neither a primary nor secondary diagnosis of heart failure, disclosure of BNP results caused heart failure to become the primary diagnosis in one patient (2%) and a secondary diagnosis in 4 patients (9%), and led to five changes in medical management. Thus, for ED patients with a primary clinical diagnosis of heart failure, BNP testing had no impact on medical decision-making. However, for other patients with dyspnea, elevated BNP levels did influence medical decision-making, particularly when heart failure was in the differential diagnosis.