Risk factor analysis of pneumothorax associated with persistent pulmonary hypertension of the newborn in Thai neonates

Abstract

Objective: To determine the risk factors and outcomes of persistent pulmonary hypertension of the newborn (PPHN)-associated pneumothorax (PTX).

Study design: The medical records of infants diagnosed with PPHN with or without PTX from January 2012 to July 2017 were retrospectively reviewed.

Results: Of the 102 included PPHN infants, PTX was found in 32 (31.4%) infants with 43.8% (14/32) mortality. PTX was significantly associated with increased mortality with an odds ratio (OR) of 5.27 (95% confidence interval [CI] 1.96–14.17). Unilateral PTX was more common than bilateral PTX (53.1 versus 46.9%, respectively). Multivariate logistic regression analysis indicated that a 1-minute Apgar score of ≤7 was associated with an increased risk for PTX (adjusted OR = 2.67 [95% CI 1.14–6.25]). In subgroup analysis, each increase of maximum peak inspiratory pressure (PIP) of 1 cmH₂O significantly increased the odds of PTX by 1.46 (95% CI 1.02–2.07), while each 1 mmHg increase in arterial partial pressure of oxygen (P_aO₂) decreased the odds of PTX (adjusted OR = by 0.98 [95% CI 0.97–0.99]).

Conclusions: PTX was significantly associated with higher mortality in PPHN infants. Lower Apgar score and increasing PIP in conventional mechanical ventilation were risk factors for PTX. Higher P_aO₂ was associated with a decreased rate of PTX.

Keywords:

• Neonatal mortality
• neonatal pneumothorax
• newborn infant
• persistent pulmonary hypertension of the newborn
• pneumothorax

Acknowledgments

The authors thank Mr. Wasan Punyasang, M.S. Statistics, Research Affairs, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand, for statistical analysis, and also thank Mr. David Patterson for English advice on the manuscript.

Disclosure statement

None of the authors have any conflicts of interest.