This study aimed to elucidate the influential parameter, acquired from the analyses of nasal capnography waveforms, for the elevated plasma brain natriuretic peptide (BNP) levels in patients (n = 34) with heart failure (HF). The capnography waveforms were analyzed to evaluate changes in end-tidal CO₂ (ETCO₂) values and expiratory and inspiratory durations. The relationship between these parameters, estimated from capnography analyses and plasma BNP, was then evaluated. Mean ETCO₂ values and BNP levels showed a strong negative correlation (R² = 0.6355, p < 0.0001) in HF patients with chronic kidney disease (CKD) (R² = 0.6355, p < 0.0001). The ETCO₂ value was the most influential parameter that indicated elevated BNP levels in HF patients with CKD (β = − 0.577; p = 0.031). The mean ETCO₂ level could be a potentially influential parameter reflecting elevated BNP levels in HF patients, especially in HF patients with CKD. Respiratory parameters, acquired from detailed nasal capnography analyses, might be reasonable for evaluating the severity of HF.

Graphical abstract

这项研究旨在阐明从鼻二氧化碳波形分析获得的影响参数，用于心力衰竭（HF）患者（n = 34）血浆脑利钠肽（BNP）水平升高。分析了二氧化碳分析波形，以评估潮气末CO ₂（ETCO ₂）值以及呼气和吸气时间的变化。然后，对通过二氧化碳分析和血浆BNP估计的这些参数之间的关系进行了评估。在患有慢性肾脏病（CKD）的HF患者中，平均ETCO ₂值与BNP水平呈强负相关（R ² = 0.6355，p <0.0001）（R ² = 0.6355，p <0.0001）。ETCO ₂值是最有影响力的参数，表明CKD HF患者的BNP水平升高（β = − 0.577；p = 0.031）。平均ETCO ₂水平可能是潜在影响因素，反映了HF患者（尤其是CKD HF患者）的BNP水平升高。通过详细的鼻二氧化碳图分析获得的呼吸参数对于评估HF的严重性可能是合理的。

图形概要