Update on PPHN: mechanisms and treatment

Semin Perinatol. 2014 Mar;38(2):78-91. doi: 10.1053/j.semperi.2013.11.004.

Abstract

Persistent pulmonary hypertension of the newborn (PPHN) is a syndrome of failed circulatory adaptation at birth, seen in about 2/1000 live born infants. While it is mostly seen in term and near-term infants, it can be recognized in some premature infants with respiratory distress or bronchopulmonary dysplasia. Most commonly, PPHN is secondary to delayed or impaired relaxation of the pulmonary vasculature associated with diverse neonatal pulmonary pathologies, such as meconium aspiration syndrome, congenital diaphragmatic hernia, and respiratory distress syndrome. Gentle ventilation strategies, lung recruitment, inhaled nitric oxide, and surfactant therapy have improved outcome and reduced the need for extracorporeal membrane oxygenation (ECMO) in PPHN. Newer modalities of treatment discussed in this article include systemic and inhaled vasodilators like sildenafil, prostaglandin E1, prostacyclin, and endothelin antagonists. With prompt recognition/treatment and early referral to ECMO centers, the mortality rate for PPHN has significantly decreased. However, the risk of potential neurodevelopmental impairment warrants close follow-up after discharge for infants with PPHN.

Keywords: Hypoxic respiratory failure; Nitric oxide; Persistent fetal circulation; Pulmonary vascular resistance; Systemic vasodilators.

MeSH terms

  • Administration, Inhalation
  • Alprostadil / therapeutic use
  • Asphyxia Neonatorum / complications
  • Endothelium-Dependent Relaxing Factors / therapeutic use*
  • Epoprostenol / therapeutic use
  • Extracorporeal Membrane Oxygenation / methods*
  • Hernia, Diaphragmatic / complications
  • Hernias, Diaphragmatic, Congenital
  • Humans
  • Infant, Newborn
  • Meconium Aspiration Syndrome / complications
  • Nitric Oxide / therapeutic use
  • Oxygen Inhalation Therapy / methods
  • Oxygen Inhalation Therapy / nursing*
  • Persistent Fetal Circulation Syndrome / etiology
  • Persistent Fetal Circulation Syndrome / physiopathology
  • Persistent Fetal Circulation Syndrome / therapy*
  • Piperazines / therapeutic use
  • Pulmonary Surfactants / therapeutic use*
  • Purines / therapeutic use
  • Respiration, Artificial / methods*
  • Respiratory Distress Syndrome, Newborn / complications
  • Sildenafil Citrate
  • Sulfones / therapeutic use
  • Vascular Resistance / physiology
  • Vasodilator Agents / therapeutic use*

Substances

  • Endothelium-Dependent Relaxing Factors
  • Piperazines
  • Pulmonary Surfactants
  • Purines
  • Sulfones
  • Vasodilator Agents
  • Nitric Oxide
  • Sildenafil Citrate
  • Epoprostenol
  • Alprostadil