PNEUMATOCELE FORMATION COMPLICATING HYDROCARBON PNEUMONITIS

Pneumatoceles in preterm infants-incidence and outcome in the post-surfactant era

OBJECTIVE

Pneumatoceles are gas-filled cysts within the lung parenchyma resulting mostly from ventilator-induced lung injury and air-leak in premature infants with respiratory distress syndrome. The use of surfactant in the treatment of respiratory distress syndrome has resulted in a decrease in the incidence of air-leak disease. Our aim was to study the incidence and clinical course of pneumatoceles in the surfactant era.

STUDY DESIGN

A retrospective study of infants born at < or =30 weeks gestational age was admitted to the University of Connecticut Health Center NICU from 1998 to 2007. Pneumatoceles and other intrathoracic air-leaks were identified and comparisons were made with infants without these conditions.

RESULT

Pneumatoceles were identified in 19 preterm infants, born at gestational age < or =30 weeks, needing positive pressure ventilation for respiratory distress syndrome between the years 1998 to 2007. Pneumatoceles appeared early (median, 7th day of life; range, 1st to 28th day of life) and usually resolved with decrease in mean airway pressure (median, 4 days; range, 3 to 125 days). The majority of pneumatoceles were located in the right parahilar region (18/19). Associated intrathoracic air-leaks were pulmonary interstitial emphysema (5/19), pneumothorax (10/19), and pneumomediastinum (1/19). None of the infants required any invasive procedures to alleviate the pneumatoceles. In infants who survived, most pneumatoceles resolved with a decrease in mean airway pressure or extubation (14/15). One infant had a persistent pneumatocele for 125 days without any cardiopulmonary compromise and five infants died as a result air-leaks along with other complications of prematurity.

CONCLUSION

Pneumatoceles are a manifestation of intrathoracic air-leaks of prematurity. They are markers for ventilator-induced lung injury and are associated with significant mortality similar to other intrathoracic air-leaks. However, conservative management with reduction in mean airway pressure is effective in the resolution of this condition and interventional decompression of the pneumatocele is generally not necessary.

Computerized tomography in pneumatocoeles after paraffin ingestion

Paraffin pneumonia is a common form of poisoning but pneumatocoeles are an uncommon complication. This is a report of the computerized tomography (CT) of seven patients who developed pneumatocoeles after the ingestion of paraffin. The finding on the CT are presented and the situation and characteristics of the pneumatocoeles are indicated.

Pulmonary toxicity following gastrointestinal ingestion of kerosene

The continuous controversy concerning the treatment for acute hydrocarbon ingestions led to a study of the pulmonary effects of kerosene absorption from the gastrointestinal tract in dogs. Gastrostomies and cervical esophageal transections with a proximal esophageal fistula were performed on 11 dogs under general anesthesia. Following a return of normal bowel function each animal was given 20 cc/kg of a commercial-grade kerosene by gastrostomy tube. The dogs were randomly divided into two groups for necropsy at 24 and at 72 hours, and each dog had chest radiographs prior to instillation of the kerosene and at 6, 24, 48, and 72 hours, depending on their group. The dogs were given an overdose of barbiturate for euthanasia. Tissue was randomly selected from the lungs and examined using standard microscopic and histologic techniques. No clinical complications were observed in any of the animals following the kerosene instillation. No radiologic or histologic evidence of pulmonary changes due to kerosene was found. The lack of pulmonary pathologic changes following kerosene ingestion in dogs protected from aspiration suggests that the treatment for kerosene poisoning should be confined to supportive measures. Induction of emesis is contraindicated in the management of hydrocarbon ingestion.