Non-Invasive Bed-side assessment of pulmonary vascular resistance in critically I11 pediatric patients with acute respiratory distress syndrome

Abstract

Aim: To evaluate the degree of pulmonary hypertension as well as alterations in the pulmonary vascular resistance in critically ill children with acute respiratory distress syndrome (ARDS) using bed-side echocardiography. Methods: The study included 20 consecutive critically ill mechanically ventilated ARDS pediatric patients selected from the PICU of Ain Shams University Hospital. Patients with underlying heart disease or chronic pulmonary disease were excluded. Doppler echocardiography was done to assess the pulmonary artery pressure. Pulmonary vascular resistance was calculated using the equation (PVR= TRV/TVI (RVOT) xlO + 0.16) with a cut off value of 0.175 to determine PVR > 2 wood unit. Age and sex matched children were assessed by echocardiography as a control group. Results: Ninety percent of patients had elevated RVSP and PVR when compared to normal standard values. The median and IQR of RVSP were higher among patients 44.5 (36.348?. SmmHģ) when compared to controls 25 (23.5-26 mmHg) (pO.OOl) as well as the median and IQR of the PVR 2.6(2.1-3.4) when compared to controls 1.5(1.1- 1.6) (p<0.001).There was a significant negative correlation between hypoxemic index (Pa02 /F102) and TRV (r = - 0.474,P =0.035) and a significant positive correlation between Fİ02 and TRV(r =0.469, P =0.037), Fİ02 and Pulmonary artery end-diastolic pressure (PAEDP) (r =0.529. P = 0.017) and between Peak inspiratory pressure (PIP) and PVR (10.513= , P = 0.021). Conclusion: Hypoxemia resulted from ARDS can adversely affect the pulmonary vascular bed. Management of pulmonary vascular dysfunction could represent a future therapeutic target for patients with ARDS.

Keywords

• ards
• pulmonary vascular resistance
• echocardiography