Objective Intrathoracic pressure influences CBF in adults. The aim of the present study was to evaluate brain hemodynamics in preterm newborn with or without nCPAP in different head positions.
Methods THI and TOI were recorded using NIRS (NIRO 200 Hamamatsu) in 18 newborns (GA 22–32 weeks) in different head positions. 9 were on nCPAP (group 1) and 9 were breathing spontaneously (group 2). The effect of nCPAP, GA and systemic blood pressure on brain hemodynamics in neutral position was analyzed in a multiple regression analysis model. A repeated measures ANOVA was performed to evaluate the influence of positions on brain hemodynamics.
Results In neutral position THI was higher in group 1 than in group 2 and showed a negative correlation with GA (r = 0.6, p = 0.005). TOI showed a positive correlation only with GA (r = 0.6, p = 0.01). Head of the bed tilting but not head rotation significantly affected THI both in prone and supine position. THI decreased by tilting the head of the bed 30° upward in newborns in prone position or in supine head turned 90°.
Conclusions In neutral position very preterm newborns on nCPAP showed higher THI and lower TOI compared to those of higher GA breathing spontaneously, suggesting a reduced CBF in the first cases. Reduced venous return due to increased intrathoracic pressure may explain such findings. Tilting the head of the bed 30° upward may improve venous return. Our results support current recommendations to elevate the head of the bed 30°C in order to prevent brain injury in VLBWI.