The Effect of Continuous PEEP Administration during Surfactant Instillation on Cerebral Hemodynamics in Intubated Preterm Infants: A NIRS Study.

OBJECTIVE: There is an ongoing debate about the best and comfortable way to administer surfactant. We hypothesized that uninterrupted respiratory support and continuous PEEP implementation while instilling surfactant via endotracheal tube (ETT) with side port will result in higher regional cerebral tissue oxygenation (rcSO2) and the alterations in cerebral hemodynamics will be minimal. STUDY DESIGN: Preterm infants who required intubation in the delivery room and/or in the first 24 hours of life with gestational age <32 were enrolled. Patients were intubated either via conventional ETT or ETT with side port (Vygon) with appropriate sizes. Following neonatal intensive care unit admission a near-infrared spectroscopy (NIRS) probe was placed on the forehead and each infant was started to be monitored with NIRS. In conventional ETT group, patients separated from the ventilator while surfactant was instilled. In ETT with side port group, respiratory support was not interrupted during instillation. Heart rate, oxygen saturation, rcSO2, cerebral fractional tissue oxygen extraction (cFTOE), and blood pressures were recorded. RESULTS: A total of 46 infants were analyzed. Surfactant was instilled with conventional ETT in 23 and ETT with side port in 23 infants. Birth weights (1,037 ± 238 vs. 1,152 ± 277 g) and gestational ages (28 ± 2.3 vs. 29 ± 1.6 weeks) did not differ between groups. During instillation of surfactant, rcSO2 levels [61.5 (49-90) vs. 70 (48-85)] and cFTOE levels 0.28 (0.10-0.44) vs. 0.23 (0.03-0.44)] were similar (p = 0.58 and 0.82, respectively). CONCLUSION: Interruption of respiratory support during surfactant instillation did not significantly alter the cerebral tissue oxygenation. These results did not support our hypothesis and should be confirmed with further studies. KEY POINTS: · Monitoring intracerebral oxygenation changes during surfactant administration with NIRS is feasible.. · The surfactant administration method does not significantly alter the cerebral oxygenation.. · Surfactant administration itself rather than the method caused a transient drop in cerebral NIRS readings..

Brain Volumes of very Low Birth Weight Infants Measured by Two-dimensional Cranial Ultrasonography: A Prospective Cohort Study.

BACKGROUND: Cranial ultrasonography is the main neuroimaging technique for very low birth weight infants. Low brain volume is associated with poor neurologic outcome. This study aimed to calculate brain volumes of preterm infants with two-dimensional measurements of cranial ultrasonography. METHODS: Intracranial height, anteroposterior diameter, bi-parietal diamater, ventricular height, thalamo-occipital distance and ventricular index were measured with routine cranial ultrasonographic scanning. Brain considered a spheric, ellipsoid model and estimated brain volume (EBV) was calculated by subtracting two lateral ventricular volumes from the total brain volume. RESULTS: One hundred and twenty-one preterm infants under a birth weight of 1500 g and 32 weeks of gestational age were included in this study. The mean gestational age of study population was 27.7 weeks, and mean birthweight was 1057 grams. Twenty-two of 121 infants had dilated ventricle, in this group, EBV was lower than normal group (202 ± 58 cm3 vs 250 ± 53 cm3, respectively, p<0.01). Advanced resuscitation, bronchopulmonary dysplasia and late-onset sepsis were found to be independent risk factors for low brain volume in our data. CONCLUSION: Estimated brain volume can be calculated by two-dimensional measurements with cranial ultrasonography.