Background: Understanding the relationships among right ventricle (RV) function, pulmonary hypertension, pneumonia, and respiratory failure is highly important in the management of these patients in the Pediatric Intensive Care Unit (PICU). We aimed to investigate the associations between right ventricular dysfunction and/or pulmonary hypertension in addition to lower respiratory tract infection and respiratory failure.

Methods: We conducted this cross-sectional study on 56 patients who had lower respiratory tract infections as well as respiratory failure and who were admitted to the PICU. Routine laboratory investigations and chest X-rays were performed on all patients. The Pediatric Risk of Mortality (PRISM) score was assessed in addition to conventional echocardiographic evaluation for the assessment of RV systolic function and pulmonary hypertension (PH).

Results: Increasing the PRISM-III score significantly independently correlated with increased the risk of pulmonary hypertension by 3.459-fold. Significant relationships were revealed between the presence of pulmonary hypertension and Fractional Area Change (FAC), Tricuspid Annular Plane Systolic Excursion (TAPSE), Tricuspid Regurgitation (TR) velocity, Peak Atrial A Wave Velocity (PAAT), and Tissue Doppler Imaging of the Aortic Valve (TAS); changes in Inferior Vena Cava (IVC) diameter; respiration; and the E/A ratio. The TAPSE, FAC, PAAT, TAS velocity and Early Mitral Inflow Velocity (E) to Late Mitral Inflow Velocity (A) E/A ratio were significantly greater among patients without pulmonary hypertension.

Conclusions: High rates of PH leading to respiratory insufficiency among children with lower respiratory tract infections affect a number of clinical outcomes, including mortality, PICU stay length, and duration of mechanical ventilation.