Comparison of high-flow and conventional nasal cannula oxygen in patients undergoing endobronchial ultrasonography

ECMO-assisted bronchoscopic therapy for severe tracheal stenosis: a case report and literature review

BACKGROUND

Severe tracheal stenosis is a life-threatening condition that often requires immediate intervention. Traditional surgical approaches may be challenging in critically ill patients, and bronchoscopic therapies have emerged as a less invasive alternative. However, maintaining adequate oxygenation and ventilation during these procedures can be challenging, especially in patients with near-complete airway obstruction. The manipulation of the already compromised airway during bronchoscopy can exacerbate respiratory insufficiency, leading to hypoxemia, hypercapnia, and even cardiac arrest. To address these challenges, extracorporeal membrane oxygenation (ECMO) has been increasingly utilized as a supportive measure during high-risk airway interventions. The use of ECMO in managing severe tracheal stenosis is a relatively recent development, with growing evidence supporting its role in facilitating complex airway interventions. By ensuring hemodynamic stability and adequate gas exchange, ECMO enables the safe and effective application of bronchoscopic techniques in critically ill patients who would otherwise be deemed unsuitable for such procedures. This approach can improve outcomes and expand treatment options for patients with severe tracheal stenosis.

CASE PRESENTATION

A 49-year-old woman, who underwent metal stent placement in her upper trachea 24 years ago due to tuberculous tracheal stenosis, was hospitalized due to worsening dyspnea. A thorough evaluation showed that the entire tracheal section was narrowed, with the smallest diameter measuring approximately 4-5 mm. Traditional respiratory support was inadequate for maintaining the patient's oxygen levels during bronchoscopy. We conducted bronchoscopic treatment with ECMO support, significantly alleviating the patient's dyspnea symptoms post-treatment. This is the first documented case of ECMO being utilized alongside bronchoscopy for patients with tracheal narrowing caused by tuberculosis.

CONCLUSION

The case study described a patient experiencing severe tracheal scar stenosis due to tuberculosis, who underwent successful treatment that included bronchoscopy supported by ECMO. Our effective handling of this case has provided crucial insights and strategies for managing similar situations in the future.

Effect of high flow nasal cannula versus conventional nasal cannula oxygen therapy in patients undergoing endobronchial ultrasound-guided transbronchial needle aspiration

Patients undergoing endobronchial ultrasound-guided fine needle aspiration may have multiple comorbidities, contributing to higher risks of hypoxia and adverse events, such as arrhythmias. The current study compared the efficacy of two oxygenation modalities: the high-flow nasal cannula (HFNC) vs. conventional oxygen therapy (CNC). Patients were randomized to either the HFNC or the CNC arm. HFNC and CNC were initiated and escalated as per predefined protocols. The number of desaturation events [fall in saturation of peripheral oxygen (SpO2) by 3% from the baseline] and change in levels of transcutaneous CO2 (tcCO2) from baseline were noted. Subgroup analysis was done in patients with cardiopulmonary comorbidities and in patients with SpO2<97%. A total of 122 patients were randomized. Overall, there was no significant difference in the number of desaturation events and change in tcCO2 levels; however, in patients with cardiopulmonary comorbidities (obstructive sleep apnea, heart diseases, and stable chronic obstructive airway disease), 50% in the HFNC arm had no desaturation compared to 11.7% in the CNC arm (p=0.007). 41.17% of patients in the HFNC arm had a rise in tcCO2 levels, compared to 36.11% of patients in the CNC arm (p>0.5). In patients with SpO2<97%, 48.88% in the HFNC arm had no desaturations compared to 14.70% in the CNC arm (p=0.001); there was no statistical difference in rise in tcCO2. Hence, HFNC would be a better modality for oxygenation in patients with a high risk of hypoxia without increasing the risk of hypercapnia.

Laryngeal mask airway or high-flow nasal cannula versus nasal cannula for advanced bronchoscopy: a randomised controlled trial

Background

Advanced bronchoscopic procedures have become a widely prevalent evaluation and treatment modality. These procedures require appropriate sedation and respiratory support. This study directly compares three respiratory support methods during advanced bronchoscopy.

Methods

This three-arm, prospective, block randomised trial included 60 consenting adult patients that were referred for advanced bronchoscopy involving endobronchial ultrasound (EBUS) with transbronchial needle aspiration and met inclusion/exclusion criteria. Patients were randomised to undergo bronchoscopy through a laryngeal mask airway (LMA) or with a high-flow nasal cannula (HFNC) or low-flow nasal cannula (NC), with bronchoscopy performed through a bite block. Demographic, procedural and clinical parameters were compared between the three groups, including complications, oxygenation, ventilation and need for intervention.

Results

Analysis according to intention to treat was made for the 20 patients in each arm. There were no significant differences in demographic parameters, pre-morbidities and procedure type and duration between groups. Hypoxia was significantly more common in the NC group (90%) compared with the LMA (45%) and HFNC (26%) groups (p<0.01). The need for interventions and their number were also lower in the LMA (40%) and HFNC (52.6%) groups compared with the NC group (90%, p<0.01). A multivariate analysis confirmed both HFNC and LMA as independent predictors of a lower rate of recurrent desaturation events and fewer complications in general compared with NC.

Conclusion

In this prospective randomised trial, we demonstrated the advantages of using LMA or HFNC over NC during advanced bronchoscopy with EBUS.

Tools used to assess comfort among patients undergoing high flow nasal cannula: A scoping review

OBJECTIVE

The aims were twofold: (a) to map tools documented in the literature to evaluate comfort among patients undergoing high flow nasal cannula (HFNC) treatment; and (b) to assess if the retrieved tools have been validated for this purpose.

METHODS

A scoping review, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews (PRISMA-ScR). In July 2023, PubMed, Scopus, CINAHL and Cochrane Library were consulted. Studies assessing comfort in adult, paediatric, and neonatal patients undergoing HFNC were included.

RESULTS

Seventy-four articles were included, among which nine (12.2 %) investigated comfort as the primary aim. Twenty-five different tools were found, classifiable into 14 types, mostly unidimensional and originating from those measuring pain. The most widely used was the Visual Analogic Scale (n = 27, 35.6 %) followed by the Numerical Rating Scale (n = 11, 14.5 %) and less defined generic tools (n = 10, 13.2 %) with different metrics (e.g. 0-5, 0-10, 0-100). Only the General Comfort Questionnaire and the Comfort Scale were specifically validated for the assessment of comfort among adults and children, respectively.

CONCLUSION

Although the comfort of patients undergoing HFNC is widely investigated in the literature, there is a scarcity of tools specifically validated in this field. Those used have been validated mainly to assess pain, suggesting the need to inform patients to prevent confusion while measuring comfort during HFNC and to develop more research in the field.

IMPLICATIONS FOR CLINICAL PRACTICE

Comfort assessment is an important aspect of nursing care. Given the lack of validation studies in the field, efforts in research are recommended.

The effectiveness of transnasal high flow nasal cannula in bronchoscopy under sedation: a systematic review and meta-analysis

Background

The objective of this study was to conduct a systematic review and meta-analysis of the clinical application effects of transnasal high flow nasal cannula compared to other conventional modalities for oxygen therapy devices in patients undergoing bronchoscopy.

Methods

A comprehensive literature search was conducted in multiple English databases, including PubMed, Web of Science, and Cochrane Library, to collect relevant studies on the application of high flow nasal cannula in patients undergoing bronchoscopy, and conducted a meta-analysis utilizing RevMan 5.4 software, following the predetermined inclusion and exclusion criteria.

Results

A total of 12 studies meeting the inclusion criteria were included, involving 1,631 patients (HFNC group: n = 811, other oxygen therapy group: n = 820). The meta-analysis results demonstrated that HFNC significantly reduced the incidence of hypoxemia and improved the minimum oxygen saturation compared to conventional oxygen therapy (RR = 0.27, 95% CI: 0.18-0.41, p < 0.00001; MD = 6.09, 95% CI: 3.73-8.45, p < 0.00001). Furthermore, HFNC showed statistically significant differences when compared to non-invasive ventilation in terms of hypoxemia incidence (RR = 3.52, 95% CI: 1.13-10.97, p = 0.03) and minimum oxygen saturation (MD = -1.97, 95% CI: -2.97--0.98, p < 0.0001). In addition, HFNC resulted in significantly shorter surgical time and higher PaO2 at the end of the procedure compared to conventional oxygen therapy (MD = 1.53, 95% CI: 0.66-2.40, p = 0.0006; MD = 15.52, 95% CI: 10.12-20.92, p < 0.00001). However, there were no statistically significant differences observed in PaCO2, EtCO2, and MAP at the end of the procedure (MD = 1.23, 95% CI: -0.74-3.20, p = 0.22; MD = -0.35, 95% CI: -3.77-3.06, p = 0.84; MD = -0.54, 95% CI: -2.44-1.36, p = 0.58).

Conclusion

When HFNC or NIV is utilized during the examination and treatment of bronchoscopy patients, both oxygenation modalities enhance oxygenation function and reduce the incidence of hypoxemia compared to conventional oxygen therapy. HFNC can be regarded as a viable alternative to NIV for specific high-risk patients undergoing bronchoscopy. It decreases the duration of bronchoscopy and improves the PaO2 levels at the end of the procedure, but does not significantly impact the PaCO2, EtCO2, and mean arterial pressure.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier 1414374462@qq.com.

Guidelines for endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA): Joint Indian Chest Society (ICS)/Indian Association for Bronchology (IAB) recommendations

Over the past decade, endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has become an indispensable tool in the diagnostic armamentarium of the pulmonologist. As the expertise with EBUS-TBNA has evolved and several innovations have occurred, the indications for its use have expanded. However, several aspects of EBUS-TBNA are still not standardized. Hence, evidence-based guidelines are needed to optimize the diagnostic yield and safety of EBUS-TBNA. For this purpose, a working group of experts from India was constituted. A detailed and systematic search was performed to extract relevant literature pertaining to various aspects of EBUS-TBNA. The modified GRADE system was used for evaluating the level of evidence and assigning the strength of recommendations. The final recommendations were framed with the consensus of the working group after several rounds of online discussions and a two-day in-person meeting. These guidelines provide evidence-based recommendations encompassing indications of EBUS-TBNA, pre-procedure evaluation, sedation and anesthesia, technical and procedural aspects, sample processing, EBUS-TBNA in special situations, and training for EBUS-TBNA.

Comparison of high-flow nasal cannula and conventional oxygen therapy for high-risk patients during bronchoscopy examination: protocol for a randomized controlled trial

INTRODUCTION

High-flow nasal cannula (HFNC) has been proven to improve oxygenation and avoid intubation in hypoxemic patients. It has also been utilized during endoscopy examination to reduce the incidence of hypoxia. However, little is known about the effects of HFNC versus conventional oxygen therapy (COT) on oxygenation during bronchoscopy examination via nasal route; particularly, no study has compared the use of HFNC with that of COT at similar F_IO₂ for patients who have high-risk factors of desaturation during bronchoscopy examination.

METHODS AND ANALYSIS

This randomized controlled trial will be implemented in four academic centers in China. Patients who have high-risk factors including hypoxemia, hypercapnia, morbid obesity, and narrow airway will be enrolled to use HFNC or COT during bronchoscopy examination. In the HFNC group, the initial gas flow will be set at 50 L/min with a fraction of inspired oxygen (F_IO₂) at 0.45, if the patient tolerates, the flow can be increased to 60L/min at most, while in the COT group, oxygen flow will be set at 6 L/min via a conventional nasal cannula. After 5 min pre-oxygenation, the bronchoscope will be inserted via the nasal route. Vital signs, oxygenation (SpO₂), and transcutaneous CO₂ (PtCO₂) will be continuously monitored. The primary outcome is the incidence of hypoxemia, defined as SpO₂ < 90% for 10 s during bronchoscopy examination, and secondary outcomes include the need for treatment escalation and adverse events.

DISCUSSION

Hypoxia is a common complication of bronchoscopy, our study attempted to demonstrate that HFNC may reduce the probability of hypoxia during bronchoscopy in high-risk patients. The results will be disseminated through peer-reviewed journals and national and international conferences.

TRIAL REGISTRATION

http://www.chictr.org.cn/ : ChiCTR2100055038. Registered on 31 December 2021.

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.

The Impact of High-flow Nasal Cannula vs Other Oxygen Delivery Devices during Bronchoscopy under Sedation: A Systematic Review and Meta-analyses

Background

The widespread diagnostic and therapeutic application of bronchoscopy is often associated with complications like desaturation. This systematic review and meta-analysis intend to scrutinize whether the high-flow nasal cannula (HFNC) is advantageous for providing respiratory support during bronchoscopic procedures under sedation, in comparison with other conventional modalities for oxygen therapy.

Materials and methods

A thorough screening of electronic databases was done till 31st December 2021 after obtaining registration in PROSPERO (CRD42021245420). Randomized controlled trials (RCT), evaluating the impact of HFNC and standard/any other oxygen-delivery devices during bronchoscopy were included in this meta-analysis.

Results

We retrieved in nine RCTs, with a total of 1306 patients, the application of HFNC during bronchoscopy led to decreased number of desaturation spells [relative risk (RR) 0.34, 95% confidence interval (CI) 0.27-0.44, I ² = 23%], higher nadir value of SpO₂ [Mean difference (MD) 4.30, 95% CI 2.41-6.19, I ² = 96%], and improved PaO₂ from baseline (MD 21.77, 95% CI 2.8-40.74, I ² = 99%), along with similar PaCO₂ values (MD -0.34, 95% CI -1.82 to 1.13, I ² = 58%) just after the procedure. However, apart from desaturation spell, the findings are significantly heterogeneous. In subgroup analysis, HFNC had significantly lesser desaturation spells and better oxygenation than low-flow devices, but in comparison to noninvasive ventilation (NIV) had a lower nadir value of SpO₂ with no other significant difference.

Conclusion

High-flow nasal cannula led to greater oxygenation and prevented desaturation spells more effectively in comparison with low-flow devices like nasal cannula, venturi mask, etc., and may be considered as an alternative to NIV during bronchoscopy in certain high-risk patients.

How to cite this article

Roy A, Khanna P, Chowdhury SR, Haritha D, Sarkar S. The Impact of High-flow Nasal Cannula vs Other Oxygen Delivery Devices during Bronchoscopy under Sedation: A Systematic Review and Meta-analyses. Indian J Crit Care Med 2022;26(10):1131-1140.

High flow nasal cannula for patients undergoing bronchoscopy and gastrointestinal endoscopy: A systematic review and meta-analysis

Background

High flow nasal cannula is gaining increasingly used in patients undergoing endoscopic procedures. We undertook this systematic review and meta-analysis to determine whether high flow nasal cannula (HFNC) could effectively minimize the risk of hypoxemia as compared with conventional oxygen therapy (COT).

Methods

We performed a comprehensive search of Pubmed, Cochrane Central Register of Controlled Trials (CENTRAL), Embase, and Web of Science. Studies involving the application of HFNC during endoscopic procedures were identified.

Results

We included 15 randomized controlled trials (7 bronchoscopy, 8 gastrointestinal endoscopy). Patients receiving HFNC during endoscopic procedures had a significantly lower risk of hypoxemia (defined as SpO2 &lt; 90%) versus COT group (risk ratio = 0.32; 95%CI (0.22–0.47), 13 studies, 4,093 patients, moderate-quality evidence, I2 = 48.82%, P &lt; 0.001). The lowest SpO2 was significantly higher in HFNC group (mean difference = 4.41; 95%CI (2.95–5.86), 9 studies, 1,449 patients, moderate-quality evidence, I2 = 81.17%, P &lt; 0.001) than those receiving COT. No significant difference was detected between groups in end-procedure partial pressure of CO2 (standard mean difference  =  −0.18; 95%CI (−0.52–0.15), 5 studies, 238 patients, moderate-quality evidence, I2 = 42.25%, P = 0.29). Patients receiving HFNC were associated a lower need for airway intervention (risk ratio = 0.45; 95%CI (0.24–0.84), 8 studies, 2,872 patients, moderate-quality evidence, I2 = 85.97%, P = 0.01) and less procedure interruption (risk ratio = 0.36; 95%CI (0.26–0.51), 6 studies, 1,562 patients, moderate-quality evidence, I2 = 0.00%, P &lt; 0.001). The overall intubation rate after endoscopy was 0.20% in both group, with no difference detected (risk ratio = 1.00; 95%CI (0.30–3.35), 7 studies, 2,943 patients, low-quality evidence, I2 = 0.00%, P = 1.00).

Conclusion

This systematic review and meta-analysis found moderate to low evidence that the application of HFNC was associated with improved oxygenation, decreased need for airway intervention, and reduced procedure interruption in patients undergoing endoscopic procedures. Future larger sample and high-quality studies are warranted to confirm our result and further investigate the effectiveness of HFNC in patients at risk.

Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier: CRD42022298032.

High-flow nasal oxygen reduces the incidence of hypoxia in sedated hysteroscopy for assisted reproduction

Backgrounds and aims

Pain is the main reason for hysteroscopy failure. In day-surgical settings, hysteroscopy procedures are commonly performed with the patient under sedation. Hypoxia is the most common adverse event during sedation and can lead to severe adverse events. This study aimed to compare the incidence of hypoxia when using high-flow nasal oxygen (HFNO) with that when using regular nasal oxygen in patients undergoing hysteroscopy with sedation.

Materials and methods

In this single-center, prospective, randomized, single-blinded study, 960 female patients undergoing elective diagnostic or operative hysteroscopy were randomly enrolled into the following two groups: the regular nasal group [O₂ (3–6 L/min) covered by an HFNO] and the HFNO group [O₂ (30–60 L/min)] from September 2021 to December 2021. All women were sedated with propofol (1.5 mg/kg) and remifentanil (1.5 μg/kg) in the operating room. The primary outcome was the incidence of hypoxia (75% ≤ SpO₂ < 90%, < 60 s).

Results

HFNO decreased the incidence of hypoxia (75% ≤ SpO₂ < 90%, < 60 s), subclinical respiratory depression (90% ≤ SpO₂ < 95%) and severe hypoxia (SpO₂ < 75% for any duration or 75% ≤ SpO₂ < 90% for ≥ 60 s) from 24.38 to 0.83%, from 11.25 to 1.46% and from 3.75 to 0%, respectively (P < 0.001).

Conclusion

In procedures conducted to treat female infertility, HFNO can reduce hypoxia during hysteroscopy in patients sedated with propofol, and it can prevent the occurrence of subclinical respiratory depression and severe hypoxia.

High-Flow vs. Low-Flow Nasal Cannula in Reducing Hypoxemic Events During Bronchoscopic Procedures: A Systematic Review and Meta-Analysis

Introduction

High-flow nasal cannula (HFNC) oxygenation method has been proven to be successful in oxygenation of patients with respiratory failure and has exhibited clinical superiority compared to low-flow nasal cannula (LFNC).

Methods

We performed a systematic review and meta-analysis to evaluate the potential favorable impact of HFNC oxygenation during bronchoscopy and related procedures like endobronchial ultrasound-transbronchial needle aspiration. Only randomized control trials (RCTs) were included in the meta-analysis.

Results

Six randomized control trials with 1,170 patients were included in this meta-analysis. Patients who underwent bronchoscopy with the use of high-flow nasal cannula experienced less hypoxemic events/desaturations, less procedural interruptions and pneumothoraxes compared to patients under low-flow nasal cannula treatment. This beneficial effect of HFNC in hypoxemic events was persistent 10 min after the end of procedure.

Conclusion

The high-flow nasal cannula (HFNC) oxygenation method could reduce hypoxemic events and related peri- and post-bronchoscopic complications.