Introduction: Use of Single-Use Flexible Bronchoscopes (SUFBs) is increasing in ICU settings because of the ease of setup, lack of reprocessing, and to reduce the risk of infections. Since SUFBs are commonly used for airway inspection and clearance of secretions in intubated patients, their suction capabilities in relation to the outer diameters are important. We conducted a bench study to assess the suction capacity of the currently available SUFBs at various fluid viscosities. Methods: A pseudo-mucus substance with a viscosity of 500 cP was made. A custom-made Smart Scale system to measure the mass of pseudo-mucus that could be suctioned by a bronchoscope in a standardized 30-second timeframe was utilized. Suction pressure of -200 mm Hg, which matches a hospital wall outlet was utilized. The suction pressure was confirmed using a manometer before each bronchoscope test. Each SUFB was tested four times, and the mean value of the mass suctioned was recorded. Suction testing was performed with the bronchoscopes in a neutral position and in a fully flexed position to evaluate the effects of flexion on the suction capability. A viscosity of 10 cP was used for the slim bronchoscopes to obtain meaningful data that could be compared. Results: Table: List of bronchoscopes tested and categorized as Large, Regular, and slim, based on the outer diameter of the scope and the diameter of the working channel. Scopes tested: Ambu aScope 4, BSCI Exalt Model B, Olympus H-Steriscope, Verathon BFlex, TSC Broncoflex, Ambu aScope 5. Figures 1,2,4, and 4 compare the amount of pseudo-mucus suctioned by large, regular, slim SUFBs, and in normal vs. flexed positions respectively. Among Large Bronchoscopes, BSCI Exalt B provided the most suction capability, followed by Bflex2.. Among Regular Bronchoscopes, TSC Xflo provided the most suction capability, followed by BSCI Exalt B. Among Slim Bronchoscope, BSCI Exalt B provided the most suction capability, followed by TSC Bronchoflex Agile. When the bronchoscopes are fully flexed, there is a reduction in the suction capability, which varies between different models. Conclusions: Knowledge of the suction capability in relation to the outer diameter is important in choosing the right bronchoscope. Our study provides the information for the currently existing bronchoscopes on the market.
Reddy et al. (Sun,) studied this question.