title: Does caffeine impair cerebral oxygenation and blood flow velocity in preterm infants?
abstract: OBJECTIVE
  The aim of the study is to assess the effects of an intravenous 10 mg/kg loading dose of caffeine base in cerebral oxygenation, cerebral Doppler blood flow velocity and cardiac output in preterm infants.
  
  
  METHODS
  Preterm neonates <34 weeks gestation were investigated at 1 and 4 h following the loading dose of caffeine using Doppler cerebral sonography, cardiac echocardiography and cerebral spatially resolved near-infrared spectroscopy.
  
  
  RESULTS
  Forty infants were studied with a mean gestational age (mean ± standard deviation) of 27.7 (±2.5) weeks, birth weight of 1155 (±431) g and a postnatal age of 2.8 (±2.2) days. Mean Anterior Cerebral Artery peak and time average mean blood flow velocity fell significantly by 14% and 17.7%, respectively at 1 h post-caffeine loading dose, which recovered partially by 4 h. Cerebral Tissue Oxygenation Index fell from pre-dose levels by 9.5% at 1 h with partial recovery to 4.9% reduced at 4 h post-dose. There were no significant changes in left or right ventricular output, transcutaneous oxygen saturation, transcutaneous PCO(2) or total vascular resistance.
  
  
  CONCLUSIONS
  A loading dose of 10 mg/kg caffeine base resulted in significant reduction at 1 h post-dose in cerebral oxygenation and cerebral blood flow velocity with partial recovery at 4 h.
authors.affiliation: Nepean Hospital Sydney West Area Health Service, Sydney, NSW, Australia. mark.tracy@ozemail.com.au
authors.forename: M B
authors.initials: MB
authors.lastname: Tracy
authors.forename: J
authors.initials: J
authors.lastname: Klimek
authors.forename: M
authors.initials: M
authors.lastname: Hinder
authors.forename: G
authors.initials: G
authors.lastname: Ponnampalam
authors.forename: S K
authors.initials: SK
authors.lastname: Tracy
mesh_terms: D001783:Blood Flow Velocity; D001921:Brain / Q000098:blood supply* / Q000187:drug effects; D002110:Caffeine / Q000008:administration & dosage / Q000009:adverse effects*; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D010101:Oxygen Consumption; D012039:Regional Blood Flow
chemical_list: D002110:Caffeine