SUMMARY Sequential real-time ultrasound examinations were performed in 174 neonates to determine the time of occurrence of cerebroventricular haemorrhage (CVH). Of Real-time ultrasound equipment has assumed an important role in the detection of intraventricular haemorrhage in preterm infants. Since there is no known risk ofthe procedure and minimal disturbance to the neonate during its use, we considered it could be employed serially to time the occurrence of cerebroventricular haemorrhages (CVH) (that is germinal layer or intraventricular haemorrhage). Subjects and methodsDuring a 12-month period all infants weighing less than 1500 g at birth, together with those exceeding this weight who had other risk factors-such as severe hyaline membrane disease requiring assisted ventilation-were examined using an ADR real-time ultrasound scanner with a 7 MHz linear array transducer. Examinations were performed as soon as possible after birth, repeated daily for 3 days, and then again at one week. The brain was examined using a series of oblique coronal sections through the anterior fontanelle by angling the transducer forwards then slowly rotating it backwards with the anterior fontanelle as the fulcrum. CVH was diagnosed when the appearance of echogenic blood clot was visible in, or immediately inferolateral to, the lateral ventricle. The extent of the haemorrhage in the anteroposterior direction was assessed by an oblique parasagittal scan. We had confirmed the accuracy of our technique previously by comparison with computerised tomography (CT) scans and necropsy results.' Results A total of 174 infants was studied. In 47 CVH was detected. Of the 124 infants of birthweight less than 1500 g, 38 (31°) developed CVH. Of the 16 infants of birthweight less than 1500 g who were outbom, 9 (56%) developed CVH (all these being present at the time of admission to our hospital), while haemorrhage occurred in 29 (27%) of the 108 very low birthweight infants born within the hospital. This difference was statistically significant (P = 0.04,

Lung function abnormalities occur in children with sickle cell disease (SCD) and may be associated with elevated pulmonary blood volume. To investigate that association, we determined whether blood transfusion in SCD children acutely increased pulmonary capillary blood volume (PCBV) and increased respiratory system resistance (Rrs5). Measurements of Rrs5 and spirometry were made before and after blood transfusion in 18 children, median age 14.2 (6.6-18.5) years. Diffusing capacity for carbon monoxide and nitric oxide were assessed to calculate the PCBV. Post transfusion, the median Rrs5 had increased from 127.4 to 141.3% predicted (p<0.0001) and pulmonary capillary blood volume from 39.7 to 64.1 ml/m2 (p<0.0001); forced expiratory volume in one second (p=0.0056) and vital capacity (p=0.0008) decreased. The increase in Rrs5 correlated with the increase in PCBV (r=0.50, p=0.0493). Increased pulmonary capillary blood volume may at least partially explain the lung function abnormalities in SCD children.

AimsSickle cell disease is the most common inherited disorder in African and Caribbean populations. Restrictive lung function abnormalities become increasingly common in older patients and indeed are characteristic of sickle chronic lung disease. Young children with SCD, however, frequently have obstructive lung function abnormalities. It is not clear whether the obstructive abnormalities are due to asthma or the elevated pulmonary capillary blood volume seen in SCD children because of their chronic anaemia. Such data are essential to determine the most effective preventative strategies. Hence, our aim was to investigate whether blood transfusion in SCD children acutely increased pulmonary capillary blood volume (PCBV) and this was associated with increased airways obstruction.MethodsMeasurements of respiratory system resistance and spirometry were made before and after blood transfusion in 18 children, median age 14.2 (6.6–18.5) years. The respiratory system resistance was measured using impulse oscillometry and a frequency of 5 Hz (Rrs5) and was used to assess small airway function. Lung function results were expressed as the percent predicted for height. Pulmonary capillary blood volume was measured using the single breath-hold method for gas transfer for carbon monoxide (DLCO) and nitric oxide (DLNO). Pulmonary membrane diffusing capacity (DMCO) and pulmonary capillary blood volume (PCBV) were then determined using the Roughton-Forster model.ResultsPost transfusion, the median Rrs5 increased from 127.4 to 141.3% predicted for height (p < 0.0001) and pulmonary capillary blood volume from 39.7 to 64.1 ml/m2 (p < 0.0001). Forced expiratory volume in one second (p = 0.0056) and vital capacity (p = 0.0008) decreased. The increase in Rrs5 correlated with the increase in PCBV (r = 0.50, p = 0.0493).ConclusionSignificant increases in pulmonary capillary blood volume and respiratory system resistance occurred immediately following blood transfusion in children with SCD. Furthermore, the increase in respiratory system resistance significantly correlated with the increase in pulmonary capillary blood volume. These results provide evidence of a potential interaction between the increased pulmonary capillary blood volume and pulmonary function abnormalities seen in SCD children.

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