title: The influence of ductal left-to-right shunting during extracorporeal membrane oxygenation.
abstract: OBJECTIVE
  The aim of this study was to analyze whether a ductal left-to-right (L-R) shunt will prolong extracorporeal membrane oxygenation (ECMO) in neonates with severe pulmonary hypertension. This report discusses the onset and termination of a ductal L-R shunt and its potential influences on ECMO when pulmonary hypertension decreases during venoarterial bypass.
  
  
  METHODS
  Twenty-nine neonates were monitored during veno-arterial ECMO, using bedside echocardiography with 12-hour interval observations.
  
  
  RESULTS
  Up to 43% of the patients showed this type of shunt already after 12 hours on bypass. In total, this type of ductal shunt was found between 12 and 72 hours on ECMO in 62% of the patients. After 72 hours, the ductal L-R shunt no longer was detected. In 38% of the patients, no ductal L-R shunt was found during ECMO. Comparisons between these 2 patient groups showed a significantly longer ECMO duration in patients with ductal L-R shunt (P <.007). The mean prolongation time was 46 hours. Also, a significant decrease of left atrium to aorta ratio (P <.01) was observed during ECMO in the ductus group after closure of the duct, illustrating the decrease in volume load for the left heart and lungs.
  
  
  CONCLUSIONS
  Ductal L-R shunting is related with a substantial prolongation of the ECMO course (mean prolongation of almost 2 days). The authors suggest that on one side, the ductal L-R shunt will lead to pulmonary hypercirculation and on the other side, postductal stealing from the descending aortic circulation will lead to prerenal failure. Possibly because of interactions with pulmonary and renal function, a ductal L-R shunt will, among other factors, interfere with weaning from ECMO, resulting in a prolonged bypass time.
authors.affiliation: Department of Neonatology, Children's Heart Center, Nijmegen, The Netherlands.
authors.forename: R
authors.initials: R
authors.lastname: Tanke
authors.forename: O
authors.initials: O
authors.lastname: Daniels
authors.forename: A
authors.initials: A
authors.lastname: Van Heyst
authors.forename: H
authors.initials: H
authors.lastname: Van Lier
authors.forename: C
authors.initials: C
authors.lastname: Festen
mesh_terms: D004452:Echocardiography; D015199:Extracorporeal Membrane Oxygenation / Q000379:methods*; D005260:Female; D006439:Hemodynamics; D006548:Hernia, Diaphragmatic / Q000628:therapy; D065630:Hernias, Diaphragmatic, Congenital; D006801:Humans; D006976:Hypertension, Pulmonary / Q000503:physiopathology* / Q000517:prevention & control; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000628:therapy*; D008297:Male; D008471:Meconium Aspiration Syndrome / Q000628:therapy; D011446:Prospective Studies; D012127:Respiratory Distress Syndrome, Newborn / Q000628:therapy; D018805:Sepsis / Q000628:therapy