极低出生体重婴儿脐动脉导管血液采集量和速度对脑血容量和氧合度的影响

Aim:Blood sampling from umbilical artery catheters decreases cerebral blood volume and cerebral oxygenation.The aim of this study was to assess the impact of sampling volume and velocity.Methods:Forty-eight infants,median birthweight 965 g(480-1500 g),median gestational age 27 wk(23-34 wk),were studied during routine blood sampling from umbilical artery catheters.The sampling procedure was performed following a strict protocol for draw-up volume(1.6 ml),sampling volume(1.7 ml or 0.2 ml),re-injection volume(1.6 ml)and flushing volume(0.6 ml),time of aspiration(40 s or 80 s),reinjection(30 s)and flushing(6 s).In each infant,sampling volume and aspiration time were subject to sequential variation in a randomized fashion(1.7 ml/40 s,1.7 ml/80 s,0.2 ml/30 s).Using near-infrared spectroscopy,changes in concentrations of cerebral oxygenated and deoxygenated haemoglobin were measured,and changes in cerebral blood volume and cerebral oxygenation were calculated.Results:During all three sampling procedures,oxygenated haemoglobin decreased significantly from baseline,whereas deoxygenated haemoglobin did not change.Correspondingly,a decrease in cerebral blood volume and cerebral oxygenation occurred.This decrease was not affected significantly by extending the sampling time from 40 s to 80 s,whereas it was blunted by reducing the amount of blood withdrawn.Conclusion:Blood sampling from umbilical artery catheters induces a decrease in cerebral blood volume and cerebral oxygenation.The magnitude of the decrease depends on the blood volume withdrawn but not on sampling velocity.

早产儿脑萎缩的超声诊断结果与神经发育结果相关

Abstract Abstract Background: Intraventricular haemorrhage and periventricular leukomalacia are associated with poor outcome of very preterm infants, while the role of more subtle cerebral alterations, as detected by cranial ultrasound, is less clear. Aim: In this study, we related periventricular echodensities and signs of brain atrophy to neurodevelopmental outcome at 3 y of age. Patients and methods: All preterm infants born in 1997 in our institution with a gestational age < 32 wk or birthweight < 1500 g were subjected to repeated standardized cranial ultrasound examinations until discharge. Survivors were examined at 3 y of age employing the Bayley Scales of Infant Development II. Results: Eighty-seven infants were enrolled (birthweight 430-2500 g (median 1200 g), gestational age 24-34 wk (median 29 wk)). Periventricular echodensities were detected in 42 infants (48%); in 12 cases persisting < 7 d, in 30 cases > 7 d. At discharge, 18 infants (22%) had signs of brain atrophy. Neurodevelopmental outcome was assessed in 64 infants. Infants with signs of brain atrophy scored significantly lower on MDI (atrophy 91.8, no atrophy 101.9; P = 0.02), PDI (atrophy 91.4, no atrophy 106.5; P = 0.001) and Behaviour Rating Scale (atrophy 41.1, no atrophy 66.4; P = 0.01) than infants without atrophy. Periventricular echodensities were not related to outcome. Conclusion: Our data show that infants with sonographic signs of brain atrophy at discharge achieve lower scores in neurodevelopmental testing at 3 y.