G30. TRANSIENT ADRENOCORTICAL INSUFFICIENCY OF PREMATURITY (TAP) AND SYSTEMIC HYPOTENSION IN VERY LOW BIRTH WEIGHT INFANTS

P.C. Ng, C.H. Lee, C.W.K. Lam, K.C. Ma, T.F. Fok, I.H.S. Chan, E. Wong.

Department of Paediatrics, Department of Chemical Pathology and Centre for Clinical Trials and Epidemiological Research, Prince of Wales Hospital, Chinese University of Hong Kong

Aims: Human corticotrophin releasing hormone (hCRH) stimulation test was used: (i) to determine the relation between pituitary-adrenal response and systemic blood pressure in very low birth weight (VLBW) infants, and (ii) to characterise the endocrinological features of ‘Transient Adrenocortical insufficiency of Prematurity (TAP)’.

Study design: hCRH tests were performed on 137 VLBW infants at day 7 and 14 of life in a tertiary neonatal centre.

Results: Basal and peak serum cortisol at day 7 were associated significantly with the lowest blood pressures recorded during the first two weeks of postnatal age (r > 0.38, p < 0.0001 and r > 0.41, p < 0.0001 for basal and peak levels, respectively). These cortisol levels were also correlated significantly but negatively, with the maximum and total cumulative dose of inotropes (r > −0.22, p < 0.02), total volume of crystalloid (r > −0.22, p < 0.02), and duration of inotropic treatment (r > −0.25, p < 0.006). Although the hypotensive infants (Group 2) were significantly less mature and more sick than infants with normal blood pressure (Group 1), their basal plasma ACTH at day 14 and the peak levels at day 7 and 14 were significantly higher than infants of Group 1 (p = 0.03, p = 0.001 and p = 0.01, respectively). In contrast, both basal and peak serum cortisol at day 7 were significantly lower in Group 2 than in Group 1 infants (p = 0.004 and p = 0.001, respectively). There was, however, no significant difference in serum cortisol between the groups at day 14.

Conclusions: This study characterises the fundamental …