Neutrophil to Lymphocyte (N/L) and Platelet to Lymphocyte (P/L) Ratios in Differentiating Acute Heart Failure from Respiratory Infection.

BACKGROUND: The clinical manifestations of acute heart failure (AHF) and respiratory infection (RI) frequently overlap in patients presenting with dyspnoea at the emergency department (ED). The neutrophil to lymphocyte (N/L) and platelet to lymphocyte (P/L) ratios have been proposed as diagnostic and prognostic indices in this setting. OBJECTIVE: To evaluate the ability of N/L and P/L ratios to discriminate the cause of dyspnoea in patients admitted with an initial diagnosis of AHF-RI. METHODS: 100 consecutive dyspnoeic chronic heart failure (CHF) patients diagnosed as AHF-RI in the ED of Sotiria Chest Diseases General Hospital were monitored for a series of parameters. The diagnostic efficacy of the registered parameters in discriminating the AHF from RI patients was evaluated. RESULTS: The N/L and P/L ratios did not differ statistically depending on the pharmaceutical therapy applied in the study population, with the exception of furosemide and spironolactone-treated patients, who both had higher ratio values. In the AHF patients, only N/L was influenced by the pharmaceutical treatment administered. Patients with higher N/L ratio values were more likely to have RI-triggereddyspnoea (odds ratio, OR=1.35, 95% confidence interval-CI: 0.99-1.42, p=0.047). ROC curve (receiver operating characteristic curve) analysis revealed a significant ability of the N/L ratio to differentiate pure AHF from RI (area under the curve AUC=0.773, p<0.001, cut-off value N/L= 3.15). CONCLUSION: The N/L ratio, a cheap and easily assessed biomarker, warrants further investigation as a potential diagnostic tool for the ED physician facing dyspnoeic CHF patients.

Emergency department triage of acute heart failure triggered by pneumonia; when an intensive care unit is needed?

Community acquired pneumonia (CAP) is a frequent triggering factor for decompensation of a chronic cardiac dysfunction, leading to acute heart failure (AHF). Patients with AHF exacerbated by CAP, are often admitted through the emergency department for ICU hospitalization, even though more than half the cases do not warrant any intensive care treatment. Emergency department physicians are forced to make disposition decisions based on subjective criteria, due to lack of evidence-based risk scores for AHF combined with CAP. Currently, the available risk models refer distinctly to either AHF or CAP patients. Extrapolation of data by arbitrarily combining these models, is not validated and can be treacherous. Examples of attempts to apply acuity scales provenient from different disciplines and the resulting discrepancies, are given in this review. There is a need for severity classification tools especially elaborated for use in the emergency department, applicable to patients with mixed AHF and CAP, in order to rationalize the ICU dispositions. This is bound to facilitate the efforts to save both lives and resources.