Doppler sonographic study of the effect of indomethacin on cardiac and pulmonary hemodynamics of the preterm infant.
OBJECTIVE
Indomethacin (INDO) causes an increase in systemic vascular resistance and decrease in perfusion of important organ systems in preterm infants treated for patent ductus arteriosus (PDA). Information on the effect of INDO on cardiac and pulmonary hemodynamics of these babies is scarce.


METHODS
The left ventricular output (LVO), resistance in the ascending aorta (R(Ao)), determined mean cerebral blood velocity (cerebral-mv), ductal-peak and mean blood velocity (ductal-pv and -mv) and pulmonary artery peak and mean blood velocity (pulmonary pv and -mv) were measured, before, and up to 12 h after 0.1 mg/kg of INDO in 20 preterm infants with PDA using Doppler echocardiography.


RESULTS
LVO was abnormally high (mean+/-S.E.M.: 354+/-50 ml/min/kg) before INDO treatment, and an important left-to-right shunt through the ductus was detectable in all infants. At 1 h after INDO treatment, R(Ao) had significantly increased with a significant decrease in LVO and cerebral-mv. Ductal patency and pulmonary vascular resistance seemed not to be affected at this early stage, as indicated by unchanged ductal and pulmonary arterial blood velocities. At 4 h post-INDO, ductal-pv and -mv, and to a lesser extent pulmonary-pv and -mv, were transiently lower as compared to pre-INDO, 1 and 12 h post-INDO values. This coincided with a transient absence of clinical signs of PDA at 4 h post-INDO in a substantial number of infants. R(Ao) steadily decreased and LVO steadily increased, whereas cerebral-mv normalized from 4 h post-INDO onward.


CONCLUSIONS
no important action of INDO was detected on pulmonary arterial blood velocity or pulmonary function.
Department of Pediatrics, Division of Neonatology, University Hospital Leiden, Leiden, The Netherlands.
M J
MJ
Benders
M
M
van de Bor
F
F
van Bel
D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging; D002560:Cerebrovascular Circulation / Q000187:drug effects; D004374:Ductus Arteriosus, Patent / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000503:physiopathology*; D004452:Echocardiography; D006334:Heart Function Tests; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D007213:Indomethacin / Q000494:pharmacology* / Q000627:therapeutic use; D007231:Infant, Newborn; D011652:Pulmonary Circulation / Q000187:drug effects*; D018608:Ultrasonography, Doppler; D016277:Ventricular Function, Left / Q000187:drug effects*
D007213:Indomethacin