Is pneumothorax size on chest x-ray a predictor of neonatal mortality?

Pneumothorax in newborns may result in a significant mortality and morbidity. To predict who will survive or die is of great importance in the clinical management. The aim of this study is to address whether assessment of pneumothorax size on chest X-ray may be a predictor of prognosis in newborns presenting with pneumothorax.

Of 5929 infants admitted to our neonatal intensive care unit (NICU) from January 2007 to April 2011, 60 (1.0%) newborns presenting with pneumothorax were included in the present study. Pneumothorax size was calculated by measuring the widest transverse diameter of pneumothorax area in the posteroanterior view and dividing it by the widest transverse diameter of thoracic cavity above the diaphragm. Clinical data were collected from the patients' records.

Overall mortality rate was 30% (18 patients). Pneumothorax size was significantly higher in nonsurvivors (31.1±2.8 vs 16.4±1.4, P < 0.001). The cut-off point of pneumothorax size for predicting survival was determined as 20%. The sensitivity was 72% whereas the specificity 83%. Preterm birth, low birth weight, resuscitation at birth, need for mechanical ventilation and chest tube insertion were of great significance in predicting mortality. However, of overall significant parameters, only pneumothorax size was the independent prognostic factor by regression analysis (P = 0.02).

We conclude that the calculation of pneumothorax size in the newborns is a predictor of prognosis with high sensitivity and specificity. Furthermore newborns with pneumothorax size greater than 20% are likely to have worse prognosis.