Effects of diagnostic procedures during fiberoptic bronchoscopy on heart rate, blood pressure, and blood gases.

To investigate the effects of several endoscopic procedures like introduction of the bronchoscope, removal of the instrument, catheter suction, bronchoalveolar lavage and transbronchial biopsy on heart rate, systemic blood pressure, and transcutaneously measured blood gases 77 consecutive patients (age, 20-83 years) were studied. All patients received 101 O2/min via face mask during bronchoscopy. Sedation was performed with midazolam or diazepam. The different characteristics of each patient, e.g. age, sex, smoking habits, baseline values of heart rate and systemic blood pressure, underlying pulmonary disease and kind of premedication were examined separately to analyse their special effects on the course of bronchoscopy. During the fiberoptic bronchoscopy neither a slight decrease in transcutaneous pO2 nor a small increase in transcutaneous pCO2 led to a critical situation. Nevertheless it should be stressed that the time after removal of the instrument and finishing supplemental oxygen may be critical regarding hypoxia and hypercapnia especially in older patients with hypoxia being already present before starting the endoscopy. The hemodynamic indices did not change significantly. There was no difference between midazolam or diazepam concerning the parameters under study. If supplemental oxygen is given and adequate premedication is performed, monitoring of hemodynamics and blood gases during fiberoptic bronchoscopy is not necessary in patients without cardiovascular or respiratory risk.