PULSE OXIMETRY DURING FIBEROPTIC BRONCHOSCOPY IN LOCAL-ANESTHESIA - FREQUENCY OF HYPOXEMIA AND EFFECT OF OXYGEN SUPPLEMENTATION

The indication for oxygen supplementation during diagnostic fibreoptic bronchoscopy (FOB) in local anaesthesia was evaluated by means of pul se oximetry in 160 patients (108 men, 52 women), median age 62 years. The patients were allocated at random into four groups of each 40 pers ons, which were comparable concerning pulmonary function and the dose of benzodiazepine used for premedication. The oxygen saturation of the haemoglobin (SpO(2)) in the tip of the index finger and the pulse rat e were continuously recorded. Group 1 was examined without O-2 supplem ent. Group 2a received O-2 2 litres/min through a pharyngeal catheter. Group 3 received O-2 3 litres/min through a pharyngeal catheter. SpO( 2) mean values during FOB were 92 +/- (SD) 3% in group 1 and 96 +/- 2% in groups 2a, 2b and 3 (p<0.001). SpO(2) <85%, occurred with a freque ncy of 35% in group 1, 2.5% in group 2a, 0% in group 2b, and 2.5% in g roup 3. Tachycardia and bradycardia during FOB occurred with a frequen cy of 20% in group 1, 25% in group 2a, 18% in group 2b, and 10% in gro up 3. Pulse oximetry increases the safety of FOB, and is recommended f or routine use. During FOB, oxygen supplement 2-3 litres/min should be administered to all patients, preferably through a pharyngeal cathete r, as a preventive measure against hypoxaemia.