title: Inotropes do not increase cardiac output or cerebral blood flow in preterm piglets.
abstract: The preterm newborn is at high risk of developing cardiovascular compromise during the first day of life and this is associated with increased risk of brain injury. Standard treatments are volume expansion and administration of inotropes, typically dopamine and/or dobutamine, but there is limited evidence that inotropes improve clinical outcomes. This study investigated the efficacy of dopamine and dobutamine for the treatment of cardiovascular compromise in the preterm newborn using a piglet model.
  
  
  
  Preterm and term piglets were assigned to either dopamine, dobutamine or control infusions. Heart rate, left ventricular contractility, cardiac output, blood pressure, and cerebral and regional blood flows were measured during baseline, low (10 µg/kg/h), and high (20 µg/kg/h) dose infusions.
  
  
  
  At baseline, preterm piglets had lower cardiac contractility, cardiac output, blood pressure, and cerebral blood flow compared to term piglets. The response of preterm piglets to either dopamine or dobutamine administration was less than in term piglets. In both preterm and term piglets, cardiac output and cerebral blood flow were unaltered by either inotrope.
  
  
  
  In order to provide better cardiovascular support, it may be necessary to develop treatments that target receptors with a more mature profile than adrenoceptors in the preterm newborn.
authors.affiliation: UQ Centre for Clinical Research, The University of Queensland, Brisbane, Australia.|Perinatal Research Centre, School of Medicine, The University of Queensland, Brisbane, Australia.
authors.forename: Yvonne A
authors.initials: YA
authors.lastname: Eiby
authors.affiliation: UQ Centre for Clinical Research, The University of Queensland, Brisbane, Australia.|Perinatal Research Centre, School of Medicine, The University of Queensland, Brisbane, Australia.
authors.forename: Nicole Y
authors.initials: NY
authors.lastname: Shrimpton
authors.affiliation: School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia.|Graduate School of Medicine and Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, Australia.
authors.forename: Ian M R
authors.initials: IM
authors.lastname: Wright
authors.affiliation: UQ Centre for Clinical Research, The University of Queensland, Brisbane, Australia.|School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia.
authors.forename: Eugenie R
authors.initials: ER
authors.lastname: Lumbers
authors.affiliation: UQ Centre for Clinical Research, The University of Queensland, Brisbane, Australia.|Perinatal Research Centre, School of Medicine, The University of Queensland, Brisbane, Australia.
authors.forename: Paul B
authors.initials: PB
authors.lastname: Colditz
authors.affiliation: UQ Centre for Clinical Research, The University of Queensland, Brisbane, Australia.|Department of Obstetrics and Gynaecology, Royal Brisbane and Womens Hospital, Brisbane, Australia.
authors.forename: Greg J
authors.initials: GJ
authors.lastname: Duncombe
authors.affiliation: UQ Centre for Clinical Research, The University of Queensland, Brisbane, Australia.|Perinatal Research Centre, School of Medicine, The University of Queensland, Brisbane, Australia.
authors.forename: Barbara E
authors.initials: BE
authors.lastname: Lingwood
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects*; D002316:Cardiotonic Agents / Q000494:pharmacology*; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D003326:Coronary Circulation / Q000187:drug effects; D004280:Dobutamine / Q000494:pharmacology; D004298:Dopamine / Q000494:pharmacology; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007234:Infant, Premature; D008297:Male; D023421:Models, Animal; D009200:Myocardial Contraction / Q000187:drug effects; D012079:Renal Circulation / Q000187:drug effects; D034421:Sus scrofa; D014655:Vascular Resistance / Q000187:drug effects
chemical_list: D002316:Cardiotonic Agents; D004280:Dobutamine; D004298:Dopamine