CONTINUOUS NEGATIVE CHEST-WALL PRESSURE THERAPY FOR ASSISTING VENTILATION IN OLDER CHILDREN WITH PROGRESSIVE RESPIRATORY INSUFFICIENCY1

Abstract. Continuous negative chest-wall pressure (CNP) was used to assist ventilation in 14 children, 6 months to 14 years of age, who had progressive respiratory insufficiency caused by diffuse bilateral alveolar disease. Before the start of CNP therapy, each child had a respiratory rate>50/min, arterial oxygen tension (PaO₂)<70 mmHg (FIO₂≥50%), and arterial carbon dioxide tension (PaCO₂)<45 mmHg. The mean intrapulmonary right-to-left shunt was 28.7±3.8%. Within 6 hours after therapy was started, PaO₂ increased from 55.4±15.9 to 81.6±17.7 mmHg (p<0.005). This improvement was sustained and within 24 hours permitted a decrease in fractional concentration of inspired oxygen (FIO₂) from 51.8±6.2 to 41.0±8.4% (p<0.001) and in respiratory rate from 78.1±23.0 to 56.4±21.3 (p<0.01). There was a concomitant decrease in intrapulmonary right-to-left shunt. Four of the 14 patients developed pneumothorax that was successfully decompressed. Ten patients survived. These observations establish CNP therapy as an effective means of improving arterial oxygenation in spontaneously breathing older children. Of added significance, this mode of therapy eliminates the need for endotracheal intubation and prolonged use of muscle relaxants and sedatives. It also minimizes exposure to high FIO₂, thereby minimizing the hazards of pulmonary oxygen toxicity.