[Persistent pulmonary hypertension in newborn infants].
BACKGROUND
Persistent pulmonary hypertension of the newborn is a clinical syndrome caused by failure in the transition from fetal to neonatal circulation either to achieve or to maintain low pulmonary vascular resistance after birth. The syndrome is a complex condition associated with different cardiopulmonary disorders.


METHODS
This article presents a review of the literature and the author's own experience regarding the fetal circulation, the transition to the newborn circulation, and the mechanical and molecular regulatory factors, including a discussion of the pathophysiology, aetiology, diagnostics and main goal of treatment for persistent pulmonary hypertension of the newborn.


RESULTS
The pathophysiology of persistent pulmonary hypertension is characterised by high pulmonary vascular resistance and high pulmonary artery pressure. The blood is shunted from the right to the left circuit through the foramen ovale, ductus arteriosus and also by intrapulmonal shunts. The aetiologies can be classified as underdevelopment, maldevelopment and maladaptation of the pulmonary vasculature. The clinical signs are hypoxaemia, higher oxygenation tension and saturation in the upper rather than the lower limbs, respiratory failure, systemic hypotension and systolic cardiac murmur. The differential diagnoses are primarily serious lung disorders without persistent pulmonary hypertension, and congenital cyanotic heart defects. The diagnostic investigations are blood gas analysis, X-ray of the lung, and Doppler echocardiographic examination of the heart.


CONCLUSIONS
The main treatment goal is good oxygenation, pH in upper normal and pCO2 in lower normal levels. Positive pressure ventilation, sedation, NO gas inhalation and supporting treatment of the systemic blood pressure are usually necessary. Extracorporeal membrane oxygenation is considered as a last option.
Fugelseth
D
D
Barneintensivavdelingen Kvinne-Barn klinikken Ullevål universitetssykehus 0407 Oslo. drude.fugelseth@ulleval.no
D003937:Diagnosis, Differential; D006801:Humans; D007231:Infant, Newborn; D010547:Persistent Fetal Circulation Syndrome / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000628:therapy