Abstract
Background: High frequency jet ventilation (HFJV) is an open ventilating technique to maintain ventilation for emergency or difficult airway. However, it is unclear whether jet ventilation or conventional oxygen therapy (COT) is more effectively and safely to maintain adequate oxygenation in patients with airway stenosis during bronchoscopic intervention (BI) under deep sedation.Methods: A prospective randomized cohort study was conducted to compare HFJV with normal frequency jet ventilation (NFJV) and COT (high flow oxygen) in oxygen supplementation during BI under deep sedation from March 2020 to August 2020. Patients receiving BI under deep sedation were randomly divided into 3 parallel groups of 50 patients each: the COT group (FiO21.0, 12 L/min), the NFJV Group (FiO2 1.0, driving pressure 0.1MPa, respiratory rate (RR) 15bpm) and HFJV Group (FiO2 1.0, driving pressure 0.1MPa, RR 1200bpm). SpO2, MBP and HR were recorded during the whole procedure. Arterial blood gas was examined and recorded at 15 minutes after initiation of procedure. Procedure duration, dose of anesthetics and adverse events during BI in the three groups were also recorded.Results: A total of 161 patients were enrolled with 11 patients excluded. Clinical characteristics were similar among the three groups. PaO2 of HFJV group was significantly higher than that of COT and NFJV group (P<0.001). PaO2 was significantly correlated with ventilation mode (P<0.001), BMI (P=0.019) and procedure duration (P=0.001). Multiple linear regression showed that only BMI and procedure duration were independent influencing factors of arterial blood gas PaO2 (P=0.040, P=0.002). The location of airway lesions and severity of airway stenosis were no statistical correlation with PaCO2 and PaO2.Conclusions: HFJV can effectively and safely improve intra-operative PaO2 in patients with airway stenosis during BI in deep sedation, and doesn’t increase intra-operative PaCO2 and the risk of hypercapnia. The location of airway lesions and severity of airway stenosis may not affect oxygenation maintain during basic and some advanced BI.Trial registration: Chinese Clinical Trial Registry. Registration number, ChiCTR2000031110, registered on March 22, 2020.
Specific changes in the partial pressure of arterial blood carbon dioxide observed during high-frequency jet ventilation in dogs.