Introduction
Cardiac injury may occur in ARDS patients with structurally normal hearts and may be correlated with respiratory parameters [1]. We aimed at observing NT-proBNP, troponin I and troponin T relations with different respiratory parameters in ARDS.
Methods
Inclusion criteria were any adult patient diagnosed to have ARDS according to the criteria of the American-European Consensus Conference in 1994. Exclusion criteria were any structural heart disease by echo, pulmonary embolism, atrial fibrillation, renal insufficiency, and age <18. All patients benefited from a lung protective ventilation strategy. Plasma NT-proBNP, troponin I and troponin T were measured on day 0 and on day 2 and day 7 of ARDS diagnosis. PH, PaCO2, PaO2, P(A-a)O2 (alveolar-arterial gradient), PaO2/FiO2 ratio, a/A ratio, PEEP, PIP (peak airway pressure), Pmean, Pplat (plateau pressure) and Ceff (effective compliance), and Raw (airway resistance) were monitored daily.
Results
The study comprised 20 patients with mean age of 58.9 ± 20.69 years, 11 men versus nine women (P >0.05). NT-proBNP was negatively correlated with PH on day 2 (P = 0.008, r = -0.53) and day 7 with (P = 0.02, r = -0.50). NT-proBNP was positively correlated with PEEP on day 2 (P = 0.05, r = 0.46) and day 7 (P = 0.035, r = 0.48). NT-proBNP was negatively correlated with the PaO2/FiO2 ratio on day 7 (P = 0.0035, r = 0.60). However, there was no significant correlation between NT-proBNP and other respiratory indices including PaCO2, HCO3, PaO2, SaO2, FiO2, PAO2, P(A-a)O2 and a/A ratio (P >0.05). Neither troponin I nor troponin T showed any significant correlation with any respiratory indices PH, PEEP, PaO2/FiO2, PaCO2, HCO3, PaO2, SaO2, FiO2, PAO2, P(A-a) O2 and a/A ratio on any day (P >0.05). None of the cardiac markers NT-proBNP, troponin I or troponin T showed any significant correlation with the lung mechanics parameters Cdyn, Raw, Ceff, PIP, Pplat, and Pmean (P >0.05).
Conclusion
High NT-proBNP level was correlated with high PEEP, low PH and low PaO2/FiO2 ratio while troponin T and troponin I did not show significant correlations with respiratory parameters in ARDS patients with structurally normal hearts.
References
- Mitaka C. et al. Increased plasma concentrations of BNP in patients with ALI. J Crit Care. 1997;12:66–71. doi: 10.1016/S0883-9441(97)90003-4. [DOI] [PubMed] [Google Scholar]