A Study on the Effect of the Combined Use of Gentle Ventilation and High-requency ntilation on the Incidence of Chronic Lung Disease

ABSTRACT

PURPOSE: This study was conducted to determine the correlation between the incidence of chronic lung disease and the combined use of gentle ventilation and high-frequency ventilation. METHODS: The subject group consisted of 63 very low birthweight infants of less than 1500gm who were born and survived through ventilator treatment in the Fatima neonatal intensive care unit for four years from January 1995 to December 1998. The analysis was performed retrospectively with medical records. Ventilator treatment was based on the combined use of gentle ventilation and high-frequency ventilation by means of the flow interruptor type of Infant star. High- frequency ventilation was carried out for 24 hours after surfactant replacement, when PaCO2 exceeded 60mmHg, or if the period of gentle ventilation exceeded one week. When the results of arterial blood gas analysis and the state of the body became stable, the aggressive weaning was performed. RESULTS: For 49(77.8%) of 63 infants, the weaning was possible within seven days. The other 14 infants(22.2%) needed ventilator treatment for more than seven days. The mean duration of ventilator treatment was 12.3 days. The causes of weaning failure included sepsis, patent ductus arteriosus, chronic lung disease, and intraventricular hemorrhage. Two infants who had received ventialtor treatment for more than two weeks were found to have incidence of chronic lung disease. CONCLUSION: It is suggested that the combined use of gentle ventilation and high-frequency ventilation can help reduce pulmonary damage, and it will be important to shorten the period of ventilator treatment.