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

Place of high-flow nasal oxygen in nonoperating room anesthesia

PURPOSE OF REVIEW

This article aims to assess the utility of high-flow nasal oxygen (HFNO) therapy in nonoperating room anesthesia (NORA) settings.

RECENT FINDINGS

The number of procedural interventions under deep sedation in NORA is still increasing. Administration of oxygen is recommended to prevent hypoxemia and is usually delivered with standard oxygen through nasal cannula or a face mask. HFNO is a simple alternative with a high warmed humidified flow (ranging from 30 to 70 l/min) with a precise fraction inspired of oxygen (ranging from 21 to 100%). Compared to standard oxygen, HFNO has demonstrated efficacy in reducing the incidence of hypoxemia and the need for airway maneuvers. Research on HFNO has primarily focused on its application in gastrointestinal endoscopy procedures. Yet, it has also shown promising results in various other procedural interventions including bronchoscopy, cardiology, and endovascular procedures. However, the adoption of HFNO prompted considerations regarding cost-effectiveness and environmental impact.

SUMMARY

HFNO emerges as a compelling alternative to conventional oxygen delivery methods for preventing hypoxemia during procedural interventions in NORA. However, its utilization should be reserved for patients at moderate-to-high risk to mitigate the impact of cost and environmental factors.

The periprocedural respiratory safety of propofol sedation in patients with a motor neuron disease undergoing percutaneous endoscopic gastrostomy insertion

Motor neuron diseases (MND), such as Amyotrophic Lateral Sclerosis (ALS) and Primary Lateral Sclerosis (PLS), may cause swallowing and respiratory problems, due to muscle weakness. Chronic enteral feeding via percutaneous endoscopic gastrostomy (PEG) is often indicated in these patients. PEG insertion is normally performed with sedation. Some guidelines withhold sedation in MND patients, due to the risk of respiratory complications. These guidelines seem to be defensive however and evidence is lacking. Our aim was to examine periprocedural respiratory complications occurring in MND patients undergoing PEG insertion with propofol sedation. A retrospective monocentre study was conducted in a referral hospital with an experienced PEG team. Patients with MND who underwent PEG insertion with propofol sedation between January 1. 2016 to January 1. 2023 were analysed to identify periprocedural respiratory complications. 46 patients were included. In five patients (10.9%) respiratory adverse events (AE) occurred, of which two serious (4.3%) and four AE (8.7%). Serious AE (SAE) were fatal in both cases: aspiration pneumonia (2.2%) and hypercapnia (2.2%) a few days after insertion. Sedation may have influenced the first case. Respiratory AE consisted of desaturation in two (4.3%), mild aspiration pneumonia in one (2.2%), and apnea in one patient (2.2%). Compared to previous studies respiratory complications and mortality had comparable prevalences.

Bilevel positive airway pressure ventilation in patients susceptible to hypoxemia during procedural sedation for colonoscopy: a prospective randomized controlled study

BACKGROUND AND AIMS

Hypoxemia is one of the most common adverse events during colonoscopy, particularly among patients who are diagnosed with obstructive sleep apnea (OSA) or are overweight. Consequently, the objective of this study was to evaluate the effectiveness of bilevel positive airway pressure (BPAP) ventilation for patients with high-risk hypoxemia during colonoscopy with sedation.

METHODS

In this trial, 127 patients who met the eligibility criteria were randomly assigned to the BPAP oxygen group and nasal cannula (NC) group. The primary endpoint was the incidence of hypoxemia.

RESULTS

Compared with the use of NC, BPAP ventilation exhibited a significant reduction in the incidence of hypoxemia, decreasing it from 23.8% to 6.3% (absolute risk difference, 17.5%; 95% confidence interval, 5.4-29.6; P = .006). Importantly, BPAP ventilation prevented the occurrence of severe hypoxemia (9.5% vs 0%; absolute risk difference, 9.5%; 95% confidence interval, 2.3-16.7; P = .035). In addition, the BPAP group required fewer airway interventions (P < .05).

CONCLUSIONS

In individuals with OSA or overweight status, the use of BPAP ventilation during colonoscopy significantly reduced the incidence of hypoxemia. (Clinical trial registration number: ChiCTR2300073193.).

Efficiency and safety of nasal positive airway pressure systems during endoscopic procedures in high-risk patients: Endo-Breath study

Background and study aims Sedation of high-risk patients is a relevant issue in interventional endoscopy. This is especially because standard oximetric monitors display only hypoxia and not the preceding hypercapnia. Therefore, the question arises whether use of a nasal positive airway pressure (nPAP) system can decrease the rate of sedation-associated events. Patients and methods A randomized, prospective trial was conducted at University Hospital Ulm, including 98 consecutive patients, identified as high-risk (American Society of Anesthesiologists physical status ≥3) and scheduled for prolonged (>15 minutes) endoscopic procedures. Patients underwent 1:1 randomization to two groups: interventional (nPAP-Mask) and control (conventional oxygen supplementation). Levels of CO 2 were measured noninvasively by transcutaneous capnometry device. The primary outcome was incidence of hypoxia (SpO 2 <90% over 10 seconds) and incidence of severe hypoxia was incidence of SpO 2 <80% over 10 seconds. One of our secondary objectives was to determine if the nPAP-Mask could result in significant CO 2 retention among high-risk patients. Results Data analysis showed lower incidence of hypoxia in the interventional group (10/47 vs. 31/251) P <0.05. Episodes of severe hypoxia (SpO 2 <80% over 10 seconds) were more frequent in the control group (8/51) compared with the intervention group (2/47) P <0.05. There was no significant difference in ΔCO 2 levels in the interventional vs. control group (-6.01±7.66 vs. -7.35±8.59 mm Hg). Conclusions In high-risk patients use of a nasal positive airway pressure system could significantly lower risk of hypoxia, especially in prolonged procedures. The nPAP-Mask does not induce CO 2 retention when compared with conventional oxygen supplementation.

High-Flow Nasal Cannula Therapy as an Adjuvant Therapy for Respiratory Support during Endoscopic Techniques: A Narrative Review

High-flow nasal cannula (HFNC) is a respiratory support technique that delivers a controlled concentration of oxygen with high flow, heat, and humidity via the nasal pathway. As it has many physiological effects, its use has increased for a variety of clinical indications; however, there is limited guidance on using HFNC as a respiratory support tool during endoscopic procedures. We conducted a narrative review to evaluate the effect of HFNC as an adjuvant tool during fiberoptic bronchoscopy (FOB), upper gastrointestinal tract endoscopy, and surgical procedures in adults. A search of the PubMed and Cochrane databases were performed. Approximately 384 publications were retrieved, and 99 were selected (93 original works and 6 case reports with a literature review). In patients who underwent FOB, HFNC appears to be superior to conventional oxygen therapy (COT) in preventing hypoxaemia. In contrast, for gastrointestinal endoscopy, the current evidence is insufficient to recommend HFNC over COT in a cost-effective manner. Finally, in surgical procedures such as laryngeal microsurgery or thoracic surgery, HFNC has been shown to be a safe and effective alternative to orotracheal intubation. As the results are heterogeneous, we advocate for the need for more quality studies to understand the effectiveness of HFNC during endoscopic procedures.

Hypercarbia and high-flow nasal oxygen use during anaesthesia - risking a failure to thrive?

Prevention of arterial oxygen desaturation during anaesthesia with high-flow nasal oxygen (HFNO) has gained greater acceptance for a widening range of procedures. However, during HFNO use there remains the potential for development of significant anaesthesia-associated apnoea or hypoventilation and the possibility of hypercarbia, with harmful cardiovascular or neurological sequelae. The aim of this study was to determine whether any HFNO-related hypercarbia adverse incidents had been reported on webAIRS, an online database of adverse anaesthesia-related incidents. Two relevant reports were identified of complications due to marked hypercarbia during HFNO use to maintain oxygenation. In both reports, HFNO and total intravenous anaesthesia were used during endoscopic procedures through the upper airway. In both, the extent of hypoventilation went undetected during HFNO use. An ensuing cardiac arrest was reported in one report, ascribed to acute hypercarbia-induced exacerbation of the patient's pre-existing pulmonary hypertension. In the other report, hypercarbia led to a prolonged duration of decreased level of consciousness post procedure, requiring ventilatory support. During the search, an additional 11 reports of postoperative hypercarbia-associated sedation were identified, unrelated to HFNO. In these additional reports an extended duration of severe acute hypercarbia led to sedation or loss of consciousness, consistent with the known effects of hypercarbia on consciousness. These 13 reports highlight the potential dangers of unrecognised and untreated hypercarbia, even if adequate oxygenation is maintained.

Examination of stabilization of sedation by Nasal High Flow in patients with endoscopic retrograde cholangiopancreatography during sedation using Dexmedetomidine

INTRODUCTION

Dexmedetomidine is used for the sedation method in the case of endoscopic retrograde cholangiopancreatography (ERCP) for the purpose of relieving patient anxiety. It has been reported that CO2 accumulated during sedation causes an arousal reaction, so how to normalize CO2 during sedation can be improved by administration of the minimum necessary sedative.Nasal High Flow oxygen therapy (NHF) uses a mild positive pressure load that improves carbon dioxide washout and reduces rebreathing to improve respiratory function and therefore is widely used to prevent hypoxemia and hypercapnia. In this study, we will investigate whether the upper airway patency would be maintained and the hypercapnia and hypoxemia during sedation would be prevented, by applying NHF as a respiratory management method to patients undergoing ERCP under sedation.

METHODS/DESIGN

In a randomized comparative study of 2 groups, the NHF device use group and the nasal cannula use group, for adult patients who visited the Nagasaki University Hospital and underwent ERCP examination under sedation. For sedation, Dexmedetomidine will be used in combination with and Midazolam and evaluation by anesthesiologist. In addition, as an analgesic, pethidine hydrochloride was administered intravenously. The total dose of the analgesic pethidine hydrochloride used in combination is used as the primary endpoint. As a secondary evaluation item, the percutaneous CO2 concentration is evaluated with a TCO2 monitor to examine whether it is effective in preventing hypercapnia. Furthermore, we will evaluate the incidence of hypoxemia with a percutaneous oxygen saturation value of 90% or less, and examine whether the use of equipment is effective in preventing the occurrence of hypercapnia and hypoxemia.

DISCUSSION

The purpose of this study was to obtain evidence for the utility of NHF as a potential therapeutic device for patients undergoing an ERCP under sedation, assessed by determining if the incidence rates of hypercapnia and hypoxemia decreased in the NHF device group, compared to the control group that did not use of this device.

Bilevel positive airway pressure for gastroscopy with sedation in patients at risk of hypoxemia: A prospective randomized controlled study

STUDY OBJECTIVE

Hypoxemia is one of the most frequent adverse events during sedated gastroscopy, and there is still no effective means to prevent and cure it. Therefore, we conducted this randomized trial to confirm our hypothesis that, compared with the nasal cannula group, bilevel positive airway pressure (BPAP) would decrease the incidence of hypoxemia in patients with obstructive sleep apnea (OSA) or overweight status undergoing gastroscopy.

DESIGN

In a single-center, prospective, randomized controlled clinical trial, 80 patients aged 18-65 years and with OSA or overweight status who underwent gastroscopy with sedation were randomly assigned to two groups: the nasal cannula and BPAP groups. The primary outcome was the incidence of hypoxemia (75% < peripheral oxygen saturation [SpO2] < 90% for >5 sand <60 s).

MAIN RESULTS

Compared to the nasal cannula group, BPAP therapy significantly decreased the incidence of hypoxemia from 40.0% to 2.5% (absolute risk difference [ARD], 37.5% [95% confidence interval (CI), 21.6 to 53.4], p < 0.001), decreased subclinical respiratory depression from 52.5% to 22.5% (ARD, 30.0% [95% CI, 9.8 to 50.2], p = 0.006), and decreased severe hypoxemia from 17.5% to 0% (ARD, 17.5% [95% CI, 5.7 to 29.3], p = 0.006). The BPAP intervention also decreased the total propofol dosage and operation time and improved anesthesiologist's satisfaction.

CONCLUSION

BPAP therapy significantly decreased the incidence of hypoxemia in patients with OSA or overweight status who underwent gastroscopy.

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

BACKGROUND

Sedation and analgesia are the integral components of modern-day upper gastrointestinal (GI) endoscopic procedures. Irrespective of the sedative agent, hypoxia is the most commonly encountered unwarranted event with sedation. The current study intends to scrutinize whether high-flow nasal oxygen (HFNO) is advantageous for providing respiratory support during upper GI endoscopic procedures over other conventional low-flow oxygen delivery modalities, e.g. nasal cannula, facemask, etc. METHODS: An extensive screening of electronic databases was done till July 31, 2022, after enlisting in International prospective register of systematic reviews (PROSPERO) (CRD42021245409). Randomized controlled trials (RCT), comparative cohort studies, case series, cross-sectional studies and case-control studies evaluating the utility of HFNO during upper GI endoscopy under sedation were included in this meta-analysis.

RESULTS

We retrieved eight randomized control studies and one longitudinal study with 3294 patients. The application of HFNO during endoscopy led to lesser incidence of desaturation spells (odds ratio [OR] = 0.23; 95% CI 0.11-0.48; I² = 71%), reduced procedural interruption (OR = 0.11; 95% CI 0.02-0.60; I² = 88%), better nadir SpO² level during procedure (mean difference [MD] = 3.16; 95% CI 0.54-5.78; I² = 73%), overall lesser incidence of sedation-related adverse events (OR = 0.63; 95% CI 0.42-0.93; I² = 25%), with no significant impact on the duration of endoscopy (MD = 0.15; 95% CI - 0.02 to 0.31, I² = 0%).

CONCLUSION

HFNO is a novel option for upper GI endoscopy under sedation.

CLINICAL TRIAL NUMBER AND REGISTRY URL

CRD42021245409 ( https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021245409 ).

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

We conducted a systematic review to evaluate the effect of high-flow nasal oxygen and conventional oxygen therapy during procedural sedation amongst adults and children. We searched MEDLINE, EMBASE and CINAHL for randomised controlled trials that reported the effects of high-flow nasal oxygen during procedural sedation. The primary outcome measure was hypoxaemia and the secondary outcomes were minimum oxygen saturation; hypercarbia; requirement for airway manoeuvres; and procedure interruptions. The quality of evidence was assessed using the revised Cochrane risk-of bias tool and grading of recommendations, assessment, development and evaluation (GRADE). Nineteen randomised controlled trials (4121 patients) including three in children were included. Administration of high-flow nasal oxygen reduced hypoxaemia, risk ratio (95%CI) 0.37 (0.24-0.56), p < 0.001; minor airway manoeuvre requirements, risk ratio (95%CI) 0.26 (0.11-0.59), p < 0.001; procedural interruptions, risk ratio (95%CI) 0.17 (0.05-0.53), p = 0.002; and increased minimum oxygen saturation, mean difference (95%CI) 4.1 (2.70-5.50), p < 0.001; as compared with the control group. High-flow nasal oxygen had no impact on hypercarbia, risk ratio (95%CI) 1.24 (0.97-1.58), p = 0.09, I²  = 0%. High-flow nasal oxygen reduced the incidence of hypoxaemia regardless of the procedure involved, degree of fractional inspired oxygen, risk-profile of patients and mode of propofol administration. The evidence was ascertained as moderate for all outcomes except for procedure interruptions. In summary, high-flow nasal oxygen compared with conventional oxygenation techniques reduced the risk of hypoxaemia, increased minimum oxygen saturation and reduced the requirement for airway manoeuvres. High-flow nasal oxygen should be considered in patients at risk of hypoxaemia during procedural sedation.

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

(1) Background: High-flow nasal cannula (HFNC) therapy or conventional oxygen therapy (COT) are typically applied during gastrointestinal (GI) endoscopic sedation. (2) Methods: We conducted a rigorous systematic review enrolling randomized controlled trials (RCTs) from five databases. Risk of bias was assessed using Cochrane’s RoB 2.0 tool; certainty of evidence (CoE) was assessed using GRADE framework. Meta-analysis was conducted using inverse-variance heterogeneity model and presented as relative risk (RR) with 95% confidence interval (CI). Trial sequential analysis was performed, and sensitivity analysis was conducted with Bayesian approach. (3) Results: Eight RCTs were included. Compared to COT, HFNC did not reduce the overall incidence of hypoxemia (RR 0.51; 95% CI 0.24–1.09; CoE: very low) but might reduce the incidence of hypoxemia in patients at moderate to high risk for hypoxemia (RR 0.54; 95% CI 0.31–0.96; and CoE: very low). HFNC might reduce the incidence of severe hypoxemia (RR 0.38; 95% CI 0.20–0.74; and CoE: low). HFNC might not affect the need of minor airway interventions (RR 0.31; 95% CI 0.08–1.22; and CoE: very low) and had no effect on procedure duration (CoE: very low); (4) Conclusions: During GI endoscopic sedation, HFNC might reduce the incidence of hypoxemia in patients at moderate to high risk for hypoxemia and prevent severe hypoxemia.