The effectiveness of high-flow nasal cannula during sedated digestive endoscopy: a systematic review and meta-analysis

Abstract

Background Studies evaluating the role of high-flow nasal cannula (HFNC) in sedated digestive endoscopy have reported conflicting results. This meta-analysis evaluates the effectiveness of HFNC in patients undergoing digestive endoscopy procedures under sedation. Methods PubMed, Medline, EMBASE, Cochrane Central Register of Controlled Trials and Web of Science, were searched from inception to 31 July 2021. Only randomized clinical trials comparing HFNC with standard nasal cannula oxygen (SNC) during sedated digestive endoscopy were included. The incidence of hypoxemia was the primary outcome, and the secondary outcome was the percentage of patients who needed airway interventions. Results Seven studies that enrolled 2998 patients were included. When compared to SNC, HFNC was associated with a significant reduction in hypoxemia incidence (OR 0.24, 95% CI 0.09 to 0.64) and airway intervention requirements (OR 0.15, 95% CI 0.03 to 0.69), with both high heterogeneity (I2 = 81% and 94%). In subgroup analysis, when hypoxemia was defined as pulse oxygen saturation (SpO2) < 90%, low risk of hypoxemia subjects who received HFNC were associated with a significant reduction in hypoxemia incidence (OR 0.02, 95% CI 0.00 to 0.07; heterogeneity I2 = 39%) and airway intervention requirements (OR 0.02, 95% CI 0.01 to 0.04; heterogeneity I2 = 15%). However, in the high risk of hypoxemia subjects, there were no significant differences between the two oxygen administration techniques in both primary (OR 0.81, 95% CI 0.36 to 1.78; heterogeneity I2 = 0%) and secondary outcomes (OR 0.85, 95% CI 0.46 to 1.59; heterogeneity I2 = 0%). Conclusions Compared to SNC, HFNC not only reduce the incidence of hypoxemia but also reduce the requirements for airway interventions during sedated digestive endoscopy procedures, especially in patients at low risk for hypoxemia. In high risk of hypoxemia patients, there were no significant differences between the two oxygen administration techniques. Trial registration PROSPERO International prospective register of systematic reviews on 28 July 2021, registration no. CRD42021264556.

Should We Use High-Flow Nasal Cannula in Patients Receiving Gastrointestinal Endoscopies? Critical Appraisals through Updated Meta-Analyses with Multiple Methodologies and Depiction of Certainty of Evidence

“…In contrast to previous SRs, our analysis showed HFNC did not reduce the overall incidence of hypoxemia [19][20][21]. This phenomenon could be explained by the different statistical models used by each SR, especially when the included studies had heterogenous study designs or zero events (i.e., zero incidence in one or both study group) [33].…”

“…However, the study designs were heterogeneous, and study results were inconsistent. Four recent systematic reviews (SRs) were published to demonstrate the benefit in use of HFNC for prevention of hypoxemia in patients who received GI endoscopies [19][20][21][22]. Based on the tool of "A Measurement Tool to Assess Systematic Reviews II" (AMSTAR2) [23], these SRs were appraised as critically low or of low quality, mainly due to lack of discussing the influence of RoB on the pooled estimates (Table A1).…”

“…Boldface of the words in the domains indicates the critical domain of AMSTAR2.Critically low is rated when a S/R has more than one flaw in critical domain, which may not provide an accurate and comprehensive summary in this topic. Hung et al[19], Zhang et al[21], Gu et al[22].…”

Effect of high‐flow nasal oxygen on hypoxaemia during procedural sedation: a systematic review and meta‐analysis

“…Six systematic reviews have been published exploring the effects of HFNO during gastrointestinal, bronchoscopy and dental interventions [ 15 , 16 , 17 , 18 , 19 , 20 ]. Although these reviews were in favour of HFNO in mitigating the risk of hypoxaemia, there was a paucity of subgroup analyses exploring the influence of covariates and how it may influence the overall interpretation of data.…”

Utility of high-flow nasal oxygen in comparison to conventional oxygen therapy during upper gastrointestinal endoscopic procedures under sedation: A systematic review and meta-analyses

“…Similarly, another systematic review also reported a lesser incidence of hypoxia (OR 0.02, 95% CI 0.00 to 0.07; heterogeneity I 2 = 39%) and airway interventions (OR 0.02, 95% CI 0.01 to 0.04; heterogeneity I 2 = 15%) with the use of high-flow nasal cannula in comparison to standard nasal cannula during digestive endoscopic procedures under sedation [ 30 ].…”