{'fraction_non_alphanumeric': 0.025466893039049237, 'fraction_numerical': 0.013016411997736276, 'mean_word_length': 4.9932203389830505, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
119 Doppler Assessment of Pulmonary Artery Pressure in Very Low Birth Weight Infants at Risk of Chronic Lung Disease

Background: Chronic lung disease (CLD) is mainly confined to very low birthweight (VLBW) infants and is a significant cause of morbidity and mortality. It appears that pulmonary hypertension plays an important part in the physiopathology of CLD and has been linked to the increased incidence of death in infants with CLD. Doppler echocardiography allows to assess non-invasively pulmonary artery pressure in these infants. The objectives are: first, to evaluate the pulmonary artery pressure changes in VLBW infants at risk of CLD, and second, to determine whether Doppler evaluation can detect the infants at risk to develop CLD.Methods: In a prospective study, all infants with a birth weight of less than 1500g were studied by serial Doppler echocardiography on day 15, 28 of life and at 36 weeks corrected age. Pulmonary artery pressure was assessed by its inverse relationship with the ratio of pulmonary artery Doppler time to peak velocity: right ventricular ejection time which was corrected for heart rate (TPV: RVET (c)). CLD was defined as oxygen dependency at 36 weeks corrected age with characteristic chest X-ray.Results: One hundred eleven infants have been studied over one year. Thirteen infants developed CLD. The TPV: RVET(c) ratios were only significantly different between the CLD group and the control group at 36 weeks corrected age. Data are presented as median [minimal-maximal] range. (* p value by Mann-Whitney test)Conclusion: This study shows that infants with CLD develop signs of elevated pulmonary artery pressure at 36 weeks corrected age, but Doppler examination at 15 and 28 d post natal age failed to predict CLD.