title: Effects of phenobarbital on cerebral blood flow velocity after endotracheal suctioning in premature neonates.
abstract: OBJECTIVE
  To examine the effect of phenobarbital administration on anterior cerebral artery blood flow velocity before and after endotracheal suctioning in premature neonates.
  
  
  METHODS
  Transcutaneous PO(2) (TcPO(2)), heart rate, mean arterial blood pressure (MABP), and Doppler velocimeter blood flow of the left anterior cerebral artery were measured before and immediately after 3 consecutive endotracheal suctioning procedures in premature neonates. Intravenous phenobarbital (20 mg/kg) was administered immediately after the first procedure.
  
  
  METHODS
  Neonatal intensive care unit.
  
  
  METHODS
  Nine neonates with a mean birth weight of 807 g (range, 620-1060 g) and a mean gestational age of 27 weeks (range, 25-30 weeks) were studied at age 8 to 12 hours.
  
  
  RESULTS
  Transcutaneous PO(2) decreased in response to endotracheal suctioning at each of the suctioning procedures before and after phenobarbital was given (P<.001). Changes in heart rate were not observed. There were increases in MABP and area under the velocity curve (AUVC) per minute in response to endotracheal suctioning before but not after phenobarbital administration (P=.046). Use of phenobarbital lowered the overall peak systolic blood flow velocity in response to endotracheal suctioning (P =.02, analysis of variance, interactions for the effect of phenobarbital therapy on the response to suctioning). Changes in end-diastolic blood flow velocity were not observed. There were decreases in the differences before and after endotracheal suctioning for MABP at 2 and 4 hours and for AUVC and peak systolic blood flow velocity 4 hours after phenobarbital was given (P =.04).
  
  
  CONCLUSIONS
  In very low-birth-weight neonates, endotracheal suctioning is associated with decreases in TcPO(2) and increases in MABP and AUVC. Treatment with phenobarbital attenuates the increases in MABP and AUVC but not the decreases in TcPO(2) after endotracheal suctioning.
authors.affiliation: Department of Pediatrics, Brown University School of Medicine, Women and Infants Hospital of Rhode Island, 101 Dudley St, Providence, RI 02905-240, USA. bstonest@wihri.org
authors.forename: G H
authors.initials: GH
authors.lastname: Burgess
authors.forename: W
authors.initials: W
authors.lastname: Oh
authors.forename: B S
authors.initials: BS
authors.lastname: Brann
authors.forename: A M
authors.initials: AM
authors.lastname: Brubakk
authors.forename: B S
authors.initials: BS
authors.lastname: Stonestreet
mesh_terms: D000704:Analysis of Variance; D019540:Area Under Curve; D001783:Blood Flow Velocity / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage*; D007231:Infant, Newborn; D007234:Infant, Premature; D019102:Infant, Very Low Birth Weight; D007442:Intubation, Intratracheal; D010100:Oxygen / Q000378:metabolism; D010634:Phenobarbital / Q000008:administration & dosage*; D013396:Suction; D018608:Ultrasonography, Doppler
chemical_list: D006993:Hypnotics and Sedatives; D010100:Oxygen; D010634:Phenobarbital