EFFECT OF MASK VENTILATION ON CEREBRAL BLOOD VOLUME (CBV) IN PRETERM INFANTS STUDIED BY NEAR INFRARED SPECTROSCOPY (NIRS)

Abstract

Mask ventilation has been reported to cause cerebral haemorrhage in preterm infants, possibly due to head compression. We used NIRS (1) to measure the effect of mask ventilation on CBV in 8 preterm infants born at 23-32 (median 27) weeks of gestation and studied aged 10-67 (23.5) days. The mask (Laerdal) was gently attached with ties and a wool bonnet. Observations were made in random order during spontaneous breathing with the mask either loosely applied, or tightly -with or without continuous positive airway pressure (CPAP) of 2-4 cm H2O or intermittent positive pressure ventilation (IPPV) at a peak airway pressure of 10-14 cm H2O, using a pressure limited ventilator. CBV changes from the loose mask mode were recorded from observations made over 5 minute periods during each mode of ventilatory support (table). The changes were very small, although ANOVA with the Scheffe test showed that CBV during CPAP differed significantly from the other periods (p<0.05). We conclude that mask ventilation had no important effect on CBV. (1) J.S.Wyatt et al. j Appl Physiol 1990;68:1086-1091.