Respiratory distress in neonates with special reference to pneumonia.

OBJECTIVE: (i) To find causes of respiratory distress in neonates brought to a referral neonatal unit with symptoms suggestive of respiratory disorder; (ii) to evaluate clinical signs for diagnosis of neonatal pneumonia; (iii) To determine bacterial etiology of neonatal pneumonia; and (iv) To determine indicators of fatality in neonatal pneumonia.

DESIGN: Prospective descriptive.

SETTING: Referral neonatal unit of a teaching hospital.

SUBJECTS: 150 neonates admitted with respiratory symptoms consecutively.

METHODS: All neonates presenting with respiratory symptoms were included in the study. The diagnosis of the cause of respiratory distress was based on guidelines recommended by the National Neonatology Forum. Clinical features, FiO2 requirement, sepsis screen, X-ray chest, blood culture and antibiotic sensitivity, arterial blood gases and other relevant investigations were documented in a structured proforma. The neonates were regularly followed up for outcome. Multivariate unweighted logistic regression was done to find out the indicators of fatality in neonatal pneumonia for those variables which were significantly associated with outcome on univariate analysis.

RESULTS: Pneumonia was found to be the most common cause (68.6%) of respiratory distress in neonates. Other conditions included hydline membrane disease (HMD), transient tachypneia of new born (TTNB), birth asphyxia with hypoxic ischemic encephalopathy (HIE) and meconium aspiration syndrome (MAS). Clinical signs and symptoms were non specific and did not differentiate between pneumonia and other causes of respiratory distress. Respiratory rate was less than 60 per minute in 11.6% neonates with pneumonia. The most common organism responsible for neonatal pneumonia was Klebsiella pneumoniae. Chest X-ray was clear in 15% of neonates with pneumonia. On univariate analysis weight < 2000 g, gestation age < 34 weeks, age at presentation < 72 hours, lethargy, absent neonatal reflexes, shock, positive C-reactive protein, positive ventilatory support, blood culture positivity, Silverman Score >3, FiO2 >40%, pH < 7.2, alveolar arterial gradient (AaDO2) > 250 mmHg and arterial alveolar tension ratio (a/A) of < 0.25 were significantly associated with mortality in neonates with pneumonia. However, on multivariate analysis, only AaDO2 of > 250 mmHg was found to be independent predictor of fatality in neonatal pneumonia.

CONCLUSION: Pneumonia was the most common cause of respiratory distress in neonates. Clinical features and X-ray chest missed the diagnosis of pneumonia in 15 cases and had to be corroborated with sepsis screen and blood culture. AaDO2 > 250 mmHg was an independent predictor of fatality in neonatal pneumonia