Efficacy of High Flow Nasal Cannula in Reducing Hypoxemia in Children Undergoing Elective Flexible Fibreoptic Bronchoscopy as Compared to Conventional Low Flow Nasal Cannula: A Randomized Controlled Trial

BACKGROUND: Flexible fibreoptic bronchoscopy (FFB) is widely used in pediatric pulmonology, though hypoxemia remains a primary concern during the procedure. High-flow nasal cannula (HFNC) has shown potential in reducing hypoxemia in adults undergoing FFB. This study evaluates the efficacy and safety of HFNC versus low-flow nasal cannula (LFNC) for preventing hypoxemia during elective FFB in children. METHODS: Children aged 1 month to 18 years scheduled for elective FFB were enrolled, excluding those ineligible for sedation or requiring prior respiratory support. Participants were randomized to HFNC or LFNC groups. The Chi-Square test was used for bivariate analysis; Yates' correction or Fisher's exact test was applied where assumptions were violated. Multivariate analysis was performed to identify clinically significant factors associated with hypoxemia. RESULTS: Of 206 screened children, 122 were randomized (54.1% male; median age 39 months), with 61 in each group. Hypoxemia occurred in 37 (60.66%) HFNC and 34 (55.74%) LFNC patients, with no significant difference (p = 0.59; OR: 0.59-2.53). Complication rates-bradycardia, tachycardia, bradypnea, tachypnea, laryngospasm, and blood pressure changes were similar in both groups. Among those undergoing BAL, hypoxemia did not differ between groups (p = 0.57). No HFNC patient required resuscitation, whereas three LFNC patients developed apnea, interrupting the procedure. Multivariable analysis showed no independent predictors of hypoxemia severity (age, anemia, sedation depth; all p > 0.05). CONCLUSION: HFNC did not show superiority over LFNC in preventing hypoxemia during elective FFB in children, however, the study may have been underpowered to detect modest differences. CLINICAL TRIAL REGISTRATION: Clinical Trials Registry-India (CTRI) Registration No: CTRI/2022/08/044772 Dated: 22-08-2022). URL: https://ctri.nic.in/Clinicaltrials/rmaindet.php?trialid=71295&EncHid=72590.52664&modid=1&compid=19.