title: Aminophylline and Doppler time-averaged mean velocity in the middle cerebral artery in preterm neonates.
abstract: OBJECTIVE
  The purpose of this study was to assess the effect of an intravenous loading dose of aminophylline (6 mg/kg) on Doppler time-averaged mean velocity in the middle cerebral artery in ventilated preterm neonates.
  
  
  METHODS
  Twenty infants were studied by colour/duplex Doppler technique prior to and at 5, 10, 30 and 60 min after the administration of aminophylline.
  
  
  RESULTS
  Aminophylline treatment was associated with a statistically significant reduction in time-averaged mean velocity from baseline (P < 0.001) and an increase in heart rate (P < 0.001) at all timepoints. The largest reduction in time-averaged mean velocity of 19% (95% confidence interval -10 to -28%) occurred at 10 min post-dose. There were no statistically significant changes in transcutaneous PCO2 or mean arterial blood pressure.
  
  
  CONCLUSIONS
  The observed reduction of 19% from baseline in time-averaged mean velocity following treatment with aminophylline alone is unlikely to be of clinical importance. Whether aminophylline in combination with other drugs that decrease central blood flow velocity such as indomethacin and/or dexamethasone could result in a clinically significant reduction deserves further study.
authors.affiliation: Department of Newborn and Developmental Paediatrics, University of Toronto, Ontario, Canada.
authors.forename: J J
authors.initials: JJ
authors.lastname: Govan
authors.forename: A
authors.initials: A
authors.lastname: Ohlsson
authors.forename: M L
authors.initials: ML
authors.lastname: Ryan
authors.forename: T
authors.initials: T
authors.lastname: Myhr
authors.forename: K
authors.initials: K
authors.lastname: Fong
mesh_terms: D000628:Aminophylline / Q000008:administration & dosage / Q000494:pharmacology*; D000704:Analysis of Variance; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000494:pharmacology*; D002536:Cerebral Arteries / Q000187:drug effects* / Q000502:physiology; D002560:Cerebrovascular Circulation / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology*; D011446:Prospective Studies; D011659:Pulmonary Gas Exchange / Q000187:drug effects; D012121:Respiration, Artificial; D017585:Ultrasonography, Doppler, Transcranial
chemical_list: D001993:Bronchodilator Agents; D000628:Aminophylline