Study objectives: To assess the utility of nasopharyngeal tube insertion in the management of hypoxemia during flexible bronchoscopy (FB) in lung transplant recipients, and to determine the incidence and risk factors of upper-airway obstruction (UAO) leading to significant hypoxemia during FB.
Setting: Heart-lung transplant unit of a university hospital.
Patients and methods: Ninety-six lung transplant recipients (47 men and 49 women; mean +/- SD age, 41.4 +/- 13.1 years) underwent 714 FB procedures from January 1997 to May 2000.
Intervention: A fall in oxygen saturation (< or = 90%) in patients receiving 6 L/min of oxygen via nasal prongs was treated with insertion of a nasopharyngeal tube, continued oxygen supplementation, and withdrawal of the bronchoscope to the trachea. If oxygen desaturation persisted at < 90% despite additional oxygen administration via a 7F catheter placed either just above the larynx or in the proximal trachea, the bronchoscope was withdrawn, reversal of sedation was administered, and bag and mask ventilation was instituted until satisfactory spontaneous ventilation was achieved.
Results: Forty-six patients (47.9%) were treated with nasopharyngeal tube insertion on 102 occasions at a mean duration of 168 +/- 178 days after lung transplantation. In 90 of 102 procedures (88.2%), significant hypoxemia due to UAO was successfully treated with nasopharyngeal tube insertion. The mean oxygen saturation after nasopharyngeal tube insertion was 97 +/- 3%. Male gender, increase in body mass index after lung transplantation, and presence of obstructive sleep apnea were significant factors associated with the need for nasopharyngeal tube insertion during FB in lung transplant recipients.
Conclusions: Significant oxygen desaturation during FB in lung transplant recipients is mainly due to UAO. Insertion of a nasopharyngeal tube is a novel and a highly effective approach to the management of acute hypoxemia during FB.