5 LUNG FUNCTION TESTING(LFT) IN UPPER AIRWAY OBSTRUCTION(UAO) AND FLEXIBLE BRONCHOSCOPY(FB) IN PRETERM AND TERM INFANTS

Typical deformation of tidal breathing flow-volume-loops (TBFV) and passive expiration loops (single breath occlusion technique) are suspicious of UAO. FB identifies the pathoanatomic structure. Aim of the study was to determine the usefulness of LFT for identification and follow-up of UAO.Methods: The UAO was initially verified by LFT, FB, chest X-ray, blood-gas-analysis. In certain cases CT-Scanning or angiography were included. LFT was performed with SensorMedics2600, USA. FB (Olympus BF-N20, Japan) was executed bedside through nostril or endotracheal tube after sedation. Indication for LFT/FB was hoarseness, cough, stridor. From 4/93 to 2/94 ten infants were studied in the neonatal intensive care unit. At first LFT/FB actual weight was 3840g(median), 1760g/8400g(min/max);age 30 days(median), 4/311 (min/max). 4 infants had congenital malformations (3 oesophageal atresia, 1 vascular malformation), 6 acquired lesions (4 post intubation, 2 infections).Results: TBFV-loops and passive expiratory loops show typical alteration with UAO. FB confirmed subglottic stenosis(3), laryngeal(3) and tracheal malacia(4). In serial LFT's restitution can be demonstrated, conclusion: LFT is valuable for detection and follow-up in UAO, FB can be planned according to the LFT results.