The Systemic and Brain Oxygen Stauration Change During Bronchoscopy

Bronchofiberoscopy is a widespread invasive intervention in clinical practice with a number of diagnostic and therapeutic indications. The Clinic of Pulmonary Medicine in Debrecen carries out nearly 2000 examinations a year. The intervention is guided by the recommendation of the Vocational College for Pulmonary Medicine in 2005, but it does not contain a clear recommendation on the oxygen therapy used during the intervention. The Hungarian recommendation states that pulsoximetry is mandatory in bronchoscopy, but it does not contain information on the indications and the implementation of oxygen suplementation. The British Thoracic Society Guideline 2013 deals with the issue and makes the following statements:

• patients should be monitored for oxygen saturation under bronchofiberoscopy
• oxygen supplementation during the test is recommended if the patient's desaturation is significant (greater than 4% or less than 90%) and is over 1 minute
• during the bronchoscopy, the occurrence of oxygen saturation decreases depending on the level of initial oxygen saturation, respiratory function, co-morbidity, sedation and the course of intervention.

The aim of our study is to investigate the frequency with which systemic hypoxia occurs during bronchoscopy, what factors may contribute to its development and how the level of cerebral oxygen saturation changes with systemic desaturation (in the case of NIRS, a 20% reduction from baseline is considered significant).