The efficacy of B-type natriuretic peptide for early identification of blood loss in traumatic injury

Background Because B-type natriuretic peptide (BNP) secretion has a direct linear correlation with intravascular volume status, it was assessed as an initial marker for blood loss (BL) in polytrauma patients. Methods Hemodynamically unstable trauma patients between 18 and 45 years had serial BNP levels and hemoglobin (Hgb) levels obtained on admission, at 8 and 24 hours, and every morning during resuscitation. Results The 14 patients were categorized into 2 groups based on the 24-hour trend in Hgb levels: clinically significant blood loss (Hgb decrease >3 g/dL) or no clinical blood loss (Hgb decrease <3 g/dL). On admission, the 5 patients in the no blood loss group had normal BNP levels, whereas the 9 patients in the BL group had below-normal BNP levels. Because patients in the BL category were resuscitated, their BNP levels normalized. Conclusions BNP levels below normal are indicative of intravascular volume loss in traumatically injured patients.