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Effect of lung recruitment on pulmonary, systemic, and ductal blood flow in preterm infants

Koert de Waal1, Nick Evans, Johanna van der Lee

  • 1Emma Children's Hospital AMC, Department of Neonatology, Amsterdam, The Netherlands. koert.dewaal@hnehealth.nsw.gov.au

The Journal of Pediatrics
|April 15, 2009
PubMed

Insights

Lung recruitment during high-frequency ventilation (HFV) in preterm infants did not significantly alter pulmonary, systemic, or ductal blood flow. This suggests HFV is safe for circulatory function in neonates.

Area of Science:

  • Neonatal Physiology
  • Respiratory Medicine
  • Pediatric Cardiology

Background:

  • High-frequency ventilation (HFV) is used for preterm infants with respiratory distress.
  • Understanding the impact of lung recruitment maneuvers on circulatory function is crucial.

Purpose of the Study:

  • To assess the effects of lung recruitment on pulmonary, systemic, and ductal blood flow in preterm infants receiving primary HFV.

Main Methods:

  • Prospective cohort study of 34 preterm infants (median gestational age 28 weeks).
  • Lung recruitment monitored via oxygenation changes with stepwise continuous distending pressure (CDP).
  • Ultrasound measured right ventricular output (RVO), superior vena cava (SVC) flow, and ductus arteriosus (DA) flow at specific CDP levels.

Main Results:

  • Increasing CDP from 8 to 20 cmH2O decreased RVO by 17% but did not change SVC flow or ductal shunting.
  • Transiently low RVO and SVC flow occurred in a small number of infants at opening pressure (CDPo).

Conclusions:

  • Lung recruitment during HFV in preterm infants does not lead to clinically significant changes in circulatory blood flow.
  • HFV appears to maintain stable pulmonary, systemic, and ductal blood flow during recruitment.
Abstract

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