Flexible bronchoscopy is a common and well-tolerated diagnostic procedure in respiratory diseases. However, it can cause some distasteful effects such as cough, smother and anxiety for patients, especially during the processing of bronchoscope passing through the vocal area. The factors that affect patient satisfaction with bronchoscopy can be divided into patient characteristic, process or procedure factors, and operative experience of bronchoscopist [1,5]. A questionnaire to assess patient satisfaction with FB conducted under conscious sedation, found that male gender, shorter examination time, excellent bronchoscopist quality and less discomfort from coughing, pharyngeal pain and swallowing were associated with greater patient satisfaction . During bronchoscopy, the patients have a more intense reaction when bronchoscope passes through the glottis and then some even need to repeatedly insert the bronchoscope. Therefore, it is essential to master the ability of successfully passing through the glottic.
The main cardiac bronchoscopy complications are arrhythmias and myocardial ischemia, clinically manifest in the increasing of blood pressure and heart rate . Hypoxemia, resulting from respiratory depression by sedative drugs using and worsening on passage through the vocal cords, is also common during bronchoscopy. The majority of desaturations are transient and do not require specific intervention. In addition, oxygen desaturation is associated with an increase in cardiac workload with elevations of blood pressure and heart rate. Atrial arrhythmias occur at widely differing stages of the procedure, and ventricular arrhythmias occur mainly on passage through the vocal cords. In our study, 78.5% patients underwent bronchoscope passing through the glottis successfully at one time. There was no instance of severe complications among 200 patients. Moreover, we did not find significant cardiac complications and hypoxemia differences in the 2 groups during bronchoscope passing through vocal cords. However, one-time success passing showed statistically significantly decrease in the procedural time, and the probability of bleeding in nasal mucosa and cough of patients.
Laryngeal exposure has been classically regarded as a key factor in bronchoscope passing through glottis. Therefore, the proper positioning of a patient before bronchoscopy is a critical step. During laryngoscopy and intubation, the sniffing and simple extension positions are considered as the optimal patient positions to attain adequate visualization of the entire vocal area [8,9]. Bronchoscopy is typically performed either in the supine or the semi-recumbent or sitting posture, mainly depended on the bronchoscopist habit in different institutions . Various studies have investigated the influence of posture on the oxygen desaturation and patient satisfaction. Van Zwam et al. showed the sitting position was associated with oxygen desaturation with a relative risk of 2.46 compared to the supine position, whereas patient comfort showed no difference . However, a prospective study by Meghjee S.P et al. described there was no significant difference on oxygen desaturation between supine and semi-recumbent position . In our study, the supine positions were divided into neutrality and extension depending on with or without pillow. The extend supine position was more beneficial to successfully passing through glottis when compared to neutral supine position during bronchoscopy.
Cough has been found to be reliably associated with the level of patient discomfort during bronchoscopy . With the development of painless technology, patients and physicians usually prefer sedation for bronchoscopy to reduce discomfort . The anesthesia methods used for bronchoscopy mainly include general and local anesthesia. Lidocaine is the most commonly used for local anesthesia which applied via the bronchoscope working channel. Antoniades N et al. found that local lidocaine administered to the larynx and tracheobronchial tree significantly decreased cough frequency and reduced the requirement for sedative drugs in a randomized controlled trial . A recent study reported that the patients who was given 1% tetracaine injection pure liquid as local anesthesia had better glottis opening, mild cough response and better tolerance, and the bronchoscope was easier to pass through the glottis . In our study, cough was a higher risk factor of bronchoscope failing to pass through the glottis. The difficultly of passage process would be increased when patient coughing. Conversely, successful passage through the glottis could reduce irritation on the vocal cords and decrease the occurrence of cough. Therefore, it is crucial to adopt appropriate local anesthesia in vocal area during bronchoscopy for further study.
In conclusion, flexible bronchoscopy is a safe diagnostic procedure in respiratory diseases. Successfully passage through the glottis can save procedural time and decrease the rate of cough and bleeding of nasal mucosa during bronchoscopy. Meanwhile, the neutral position of patient and cough are two risk factors associated with failure to pass through the glottis at one time.