High-flow versus conventional nasal cannula oxygen supplementation therapy and risk of hypoxia in gastrointestinal endoscopies: a systematic review and meta-analysis

ABSTRACT

Background

Gastrointestinal endoscopy (GIE) represents a mainstay diagnostic and therapeutic procedure in clinical practice. Hypoxemia constitutes a major complication for endoscopists. Emerging evidence supports the utilization of high-flow nasal cannula (HFNC) over conventional nasal cannula (CNC) for avoidance of hypoxemia. Our aim was to compare the hypoxemia risk in patients undergoing GIE with HFNC versus CNC oxygen supplementation recruited by randomized controlled trials (RCTs).

Methods

We searched in medical databases PubMed, EMBASE and Cochrane to identify RCTs investigating the abovementioned association. Enrolled studies were evaluated for risk of bias and inserted into a random effects model for meta-analysis; subgroup analyses and publication bias were also assessed.

Results

Out of 271 articles, five RCTs were eligible (patients n=2656, HFNC 1299 and CNC 1357). A statistically significant reduced relative risk (RR) of hypoxemia among HFNC patients was revealed (RR=0.18, CI95%: 0.05–0.61), whilst with high heterogeneity (I2:79.94%, p<0.01). Patients undergoing upper GIE with HFNC displayed a significantly lower hypoxemia risk (96%, p<0.001, I2:15.59%), even after exclusion of endoscopic retrograde cholangiopancreatography cases (RR:0.03, CI95%:0.01–0.21), albeit with higher heterogeneity (I2:41.82%).     

Conclusion

Patients undergoing upper GIE with HFNC experience significantly less hypoxemia burden than CNC counterparts. Further research is warranted to target optimal safety during endoscopy.

Abbreviations: ASA, American Society of Anesthesiologists; ASGE, American Society for Gastrointestinal Endoscopy; BMI, Body Mass Index; CI, confidence interval; CNC, conventional nasal cannula; ERCP, endoscopic retrograde cholangiopancreatography; FiO_2, fraction of inspired O₂; GI, gastrointestinal; GIE, gastrointestinal endoscopies; HFNC, High-Flow nasal cannula; ICU, intensive care unit; PEEP, positive end-expiratory pressure; PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analysis; RCTs, randomized control trials; RR, relative risk (or risk ratio)

KEYWORDS:

• Gastrointestinal endoscopies
• high-flow
• HFNC
• EGD
• colonoscopy
• ERCP
• hypoxemia
• hypercapnia
• high-flow nasal cannula
• digestive endoscopies

Declaration of interest

M. Doulberis has received travel grants by Gilead Sciences Switzerland Sàrl. T. Kuntzen has received travel grants by Gilead Sciences, Vifor, Roche, Merck, Sharp & Dohme and Amgen, and Research grants by the Novartis Stiftung für klinische Forschung, and Merck, Sharp & Dohme. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Authors contributions

Conceptualization of this study belongs to F. Sampsonas. Data extraction was performed by M, Doulberis and F. Sampsonas and validation of them through V. Karamouzos and A. Tzouvelekis. Statistical analysis was performed by A. Papaefthymiou and V. Karamouzos. Manuscript was drafted – written by M. Doulberis, F. Sampsonas, A. Papaefthymiou and T. Kuntzen. M. Lagadinou, T. Karampitsakos and G. Stratakos substantially revised and critically reviewed the manuscript. All authors have read and agreed to the published version of the manuscript.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Supplementary material

Supplemental data for this article can be accessed here.

Additional information

Funding

This paper was not funded.