Pediatric airway surgery under spontaneous respiration using high-flow nasal oxygen

Oxygen concentration titration guided by oxygen reserve index during pediatric laryngeal surgery with high-flow nasal cannula oxygen: a randomized controlled trial

PURPOSE

The objective of this study was to evaluate whether adjusting the oxygen concentration guided by the Oxygen Reserve Index (ORI) during pediatric laryngeal surgery with High Flow Nasal Cannula Oxygen (HFNO) could achieve postoperative PaO2 close to physiological levels while ensuring adequate oxygenation in surgery.

METHODS

Sixty pediatric patients undergoing laryngeal surgery or examination were randomly assigned to two groups. The ORI group received oxygen concentration adjustments every 5 min to maintain a target ORI value of 0.21, whereas the control group did not undergo any adjustments. Postoperative PaO2, time weighted average fraction of inspired oxygen (FiO2), and mean Peripheral Oxygen Saturation (SpO2) were compared between groups. Finally, some analyses were conducted to examine the relationship of ORI with PaO2.

RESULTS

In general, the postoperative PaO2 was 164.9 ± 48.8 mmHg in ORI group and 323.0 ± 87.7 mmHg in control group (P < 0.01). The time weighted average FiO2 in the ORI group was 85.9 [81.8-92.7] %. There was no significant difference in mean SpO2 between the two groups (ORI vs. control: 98.4 [97.7-99.2] vs. 98.8 [97.7-99.5]; P = 0.36). According to the analyses, the optimal cut value for ORI was determined to be 0.195 when PaO2 was 150 mmHg.

CONCLUSIONS

In pediatric laryngeal surgery with HFNO, reducing oxygen concentration guided by ORI helped achieve postoperative PaO2 levels closer to physiological norms without compromising intra-operative oxygenation.

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.

Comparison of the application of high-flow nasal oxygen with two different oxygen concentrations in infant and child laryngotracheal surgery

Background

This study aimed to compare the use of the STRIVE Hi technique with 70 and 100% oxygen concentrations in children with 1st or 2nd degree laryngeal obstruction undergoing suspension laryngoscopic surgery.

Methods

Children aged 1 month to 6 years scheduled for suspension laryngoscopic surgery with spontaneous respiration were randomly divided into the 70% oxygen concentration group (HFNO70% group) and the 100% oxygen concentration group (HFNO100% group). The data recorded for all the patients included age and sex, comorbidities, preoperative physiological status, methods of induction and maintenance of anesthesia, course of the disease and surgical options, and duration of operation. The primary endpoint was the lowest oxygen saturations during the surgery. The secondary endpoints included the partial pressure of oxygen PaO2, the arterial pressure of carbon dioxide PaCO2, the peak transcutaneous carbon dioxide PtcCO2, and the incidence of desaturation (defined as SpO2 &lt; 90%) or hypercarbia (PtcCO2 &gt; 65 mmHg).

Results

A total of 80 children with 1st or 2nd degree laryngeal obstruction were included in the analysis. The median [IQR (range)] duration of spontaneous ventilation using STRIVE Hi was 52.5 [40–60 (30–170)]min and 62.5 [45–81 (20–200)]min in the HFNO 70% and HFNO 100% groups, respectively (p = 0.99); the lowest oxygen saturation recorded during the operation was 97.8 ± 2.1% and 96.8 ± 2.5%, respectively (p = 0.053); the mean PaO2 at the end of surgery was 184.6 ± 56.3 mmHg and 315.2 ± 101.3 mmHg, respectively (p &lt; 0.001); and the peak transcutaneous CO2 was 58.0 ± 13.0 mmHg and 60.4 ± 10.9 mmHg, respectively (p = 0.373), despite a long operation time.

Conclusion

STRIVE Hi had a positive effect on children undergoing tubeless laryngeal surgery with spontaneous ventilation, and for children with 1st or 2nd degree laryngeal obstruction, there was no significant difference in maintaining the intraoperative oxygenation between the 70 and 100% oxygen concentration groups. The 100% oxygen concentration group showed significant hyperoxia, which has been proven to be associated with multiple organ damage. Using a relatively lower oxygen concentration of 70% can effectively reduce the hazards associated with hyperoxia compared to 100% oxygen concentration.

Clinical trial registration

[www.chictr.org.cn], identifier [CHICTR2200064500].

Efficacy of high-flow nasal oxygenation compared with laryngeal mask airway in children undergoing ambulatory oral surgery under deep sedation: A randomized controlled non-inferiority trial

BACKGROUND

High-flow nasal oxygenation (HFNO) has been suggested as an alternative oxygenation method during procedural sedation. This randomized, non-inferiority trial evaluated the safety and efficacy of HFNO compared with laryngeal mask airway (LMA) in pediatric ambulatory oral surgery under deep sedation.

METHODS

In total, 120 children aged 2-7 years (weight: 10-30 kg) were equally assigned into two groups, namely, HFNO with propofol total intravenous anesthesia infusion (HFNO-IV) or LMA with propofol total intravenous anesthesia infusion (LMA-IV). The primary objective was to monitor carbon dioxide (CO2) accumulation during perioperative surgery. Secondary objectives included monitoring transcutaneous oxygen saturation, grade exposure to the surgical field, perioperative adverse events, or other events. The predefined non-inferiority margin was 7 mmHg. During the COVID-19 pandemic, a novel WeChat applet was implemented to gather follow-up data after discharge.

RESULTS

Non-inferiority could be declared for HFNO relative to LMA (mean difference in transcutaneous CO2 (TcCO2) = -1.4 mmHg, 95% CI: -2.9, 0.1 mmHg; P > 0.05). The pre-surgical TcCO2 of the HFNO-IV group (45.4 ± 4.5 mmHg) was similar to that of the LMA-IV group (44.0 ± 3.5 mmHg), within the clinically acceptable normal range. All the children maintained SpO2 levels of >97%. The surgical field exposure score of the HFNO group was significantly better than that of the LMA group. There was no significant difference between the two groups regarding risk or adverse events.

CONCLUSION

HFNO was not inferior to LMA for maintaining oxygenation and ventilation in patients undergoing pediatric ambulatory oral surgery under deep sedation under strict isolation from the oral cavity to the upper airway.

Apneic oxygenation in pediatric anesthesia

PURPOSE OF REVIEW

Apneic oxygenation is increasingly used in pediatric anesthesia. Its benefit for specific applications depends on the effect of apneic oxygenation on safe apnea time and carbon dioxide (CO2) elimination, on differences between low and high flow oxygen delivery, and on possible adverse effects. The present review summarizes current evidence on these pathophysiological aspects of apneic oxygenation as well as its applications in pediatric anesthesia.

RECENT FINDINGS

Apneic oxygenation with both low flow and high flow nasal oxygen increases the safe apnea time, but does not lead to increased CO2 elimination. Airway pressures and adverse effects like atelectasis formation, oxidative stress and aerosol generation under apneic oxygenation are not well studied in pediatric anesthesia. Data from adults suggest no important effect on airway pressures when the mouth is open, and no significant formation of atelectasis, oxidative stress or aerosol generation with high flow nasal oxygen.

SUMMARY

Apneic oxygenation in pediatric anesthesia is mainly used during standard and difficult airway management. It is sometimes used for airway interventions, but CO2 accumulation remains a major limiting factor in this setting. Reports highlight the use of high flow nasal oxygen in spontaneously breathing rather than in apneic children for airway interventions.

Primary versus modified secondary closure techniques for persistent tracheocutaneous fistula in pediatric patients

PURPOSE

This study aimed at compating two closure techniques for tracheocutaneous fistulas (TCFs) in pediatric patients.

METHODS

A total of 106 consecutive pediatric patients who underwent closure of a persistent TCF between April 2007 and February 2021 at a tertiary pediatric hospital were evaluated, and 103 pediatric patients aged between 12 months and 18 years were included. The clinical characteristics, perioperative outcomes, and postoperative outcomes were compared between TCF closure by primary closure (Group 1) and a modified secondary healing technique (Group 2).

RESULTS

Of the 103 patients, 58 were classified into Group 1, and 45 into Group 2. The mean age at tracheostomy and TCF closure was significantly younger in Group 2, and the interval between decannulation to TCF closure was significantly shorter in Group 2. Procedural time and hospital stay were significantly shorter in Group 2 than Group 1. Group 2 had a significantly lower complication rate, need for revision surgery, and recannulation rate than Group 1.

CONCLUSIONS

Modified secondary healing was more efficient in terms of procedural time and hospital stay, and safer (i.e., fewer complications). It is an effective surgical technique for closing a persistent TCF in younger patients more quickly after decannulation compared to primary closure.

High-flow nasal cannula application in an infant patient with laryngomalacia during general anesthesia: A case report

RATIONALE

Laryngomalacia is defined as the collapse of supraglottic structures and can cause not only strider but also trigger difficulties with ventilation and endotracheal intubation during anesthesia management. High-flow nasal cannula (HFNC) has been used to manage patients at high risk of hypoxemia in the intensive care unit; however, limited literature information is available for the application of HFNC to infant patients with laryngomalacia during anesthesia practice.

PATIENT CONCERNS

A 2-month-old male infant was scheduled to undergo surgery for inguinal hernia and undescended testis with general anesthesia.

DIAGNOSIS

The patient had subcostal retraction while breathing and frequent oxygen desaturation events and was diagnosed laryngomalacia.

INTERVENTIONS

After the patient was supplied oxygen via HFNC and then given general anesthesia, the initial 2 attempts of endotracheal intubation with a rigid laryngoscope were unsuccessful because the vocal cords were obscured by the epiglottis. A third intubation attempt was performed and successful with a 3.0-sized, uncuffed endotracheal tube within 20 minutes of the initial attempt.

OUTCOMES

No airway complications emerged and oxygen saturation remained at greater than 98% during general anesthesia. The patient was discharged 5 days after surgery without any adverse side effects.

LESSONS

Continuous oxygenation via HFNC is a good choice to prevent desaturation during difficult tracheal intubations in infant patients with laryngomalacia. This device is expected to be useful for intubation not only in patients with laryngomalacia, but also in infant patients with a predicted high risk of oxygen desaturation events during general anesthesia.

Efficacy of high-flow nasal oxygenation compared with tracheal intubation for oxygenation during laryngeal microsurgery: a randomised non-inferiority study

BACKGROUND

Oxygenation via a high-flow nasal cannula (HFNC) can be an alternative to tracheal intubation during short apnoeic procedures. This randomised, non-inferiority study assessed the efficacy of HFNC compared with tracheal intubation in laryngeal microsurgery.

METHODS

Patients (≥20 yr old) undergoing laryngeal microsurgery under general anaesthesia and neuromuscular blockade were randomised to either the HFNC or tracheal intubation groups. The primary endpoint was lowest pulse oxygen saturation (SpO₂) during the first 30 min of surgery. Secondary endpoints included incidence of desaturation (SpO₂ <95%), hypercarbia (transcutaneous carbon dioxide [CO₂] ≥8.7 kPa), and rescue intervention.

RESULTS

Amongst 130 patients randomised, 118 were included in the analysis. The lowest SpO₂ was 100 (98-100)% in the HFNC group (n=56) and 100 (100-100)% in the tracheal intubation group (n=62), with a mean difference of -1.4% (95% confidence interval: -2.4% and -0.3%), failing to confirm non-inferiority with a non-inferiority margin of 2%. The peak transcutaneous CO₂ and end-tidal CO₂ at the end of surgery were higher in the HFNC group compared with the tracheal intubation group. Incidences of desaturation, hypercarbia, and rescue intervention were more frequent in patients receiving HFNC compared with tracheal intubation.

CONCLUSIONS

HFNC oxygenation was not non-inferior to tracheal intubation for maintaining oxygen saturation during laryngeal microsurgery. Considering more frequent desaturation, hypercarbia, and requirement for rescue intervention compared with tracheal intubation, HFNC should be used with cautious monitoring even for short duration airway surgery.

CLINICAL TRIAL REGISTRATION

NCT03629353.

Application and Efficiency of Transnasal Humidified Rapid-Insufflation Ventilatory Exchange in Laryngeal Microsurgery

OBJECTIVES/HYPOTHESIS

This study aimed to analyze the feasibility of transnasal humidified rapid-insufflation ventilatory exchange (THRIVE) during laryngeal microsurgery (LMS) and investigated its efficiency and application according to the location of the lesion.

STUDY DESIGN

Retrospective chart review.

METHODS

Patients over 20 years of age who underwent LMS without underlying cardiac, pulmonary, or cerebrovascular disease were retrospectively reviewed. Overall, 54 patients with endotracheal intubation (ETI) and 44 patients with THRIVE were included. The operation and anesthesia time, induction and emergence time, oxygen saturation (SpO₂ ), and transcutaneous carbon dioxide (TcCO₂ ) levels were analyzed and compared between the two ventilation methods according to disease subsite.

RESULTS

Compared with ETI, patients with THRIVE presented reduced operation time (16.3 ± 9.69 min vs. 21.9 ± 12.0 min), anesthesia time (33.6 ± 11.4 min vs. 45.4 ± 13.9 min), emergence time (6.73 ± 2.49 min vs. 8.52 ± 3.17 min), without significant decreases in SpO₂ but with increased TcCO₂ (10.9 ± 6.12% vs. 7.33 ± 3.86%). Comparing THRIVE to ETI for lesions at the glottis yielded similar findings, which were particularly more significant. However, lesions above the glottis presented no significant difference for any parameters between THRIVE and ETI groups. Lesions involving multiple subsites and prolonged operation time were risk factors for the intraoperative conversion of ventilation method.

CONCLUSION

THRIVE is reliable for maintaining oxygenation during LMS and is efficient in reducing the operation and emergence times, leading to shorter anesthesia time, especially for lesions at the glottis. However, caution is required administering THRIVE, when lesion involves multiple subsites, and when operation time is prolonged.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

Feasibility of Surgical Treatment for Laryngomalacia using Spontaneous Respiration Technique

Objectives.

In this study, we review our institutional experience with pediatric laryngomalacia (LM) and report our experiences of patients undergoing supraglottoplasty using the spontaneous respiration using intravenous anesthesia and high-flow nasal oxygen (STRIVE Hi) technique.

Methods.

The medical records of 29 children with LM who visited Seoul National University Hospital between January 2017 and March 2019 were retrospectively reviewed. Surgical management was performed using the STRIVE Hi technique. Intraoperative findings and postoperative surgical outcomes, including complications and changes in symptoms and weight, were analyzed.

Results.

Of the total study population of 29 subjects, 20 (68.9%) were female. The patients were divided according to the Onley classification as follows: type I (n=13, 44.8%), II (n=10, 34.5%), and III (n=6, 20.7%). Twenty-five patients (86.2%) had comorbidities. Seventeen patients (58.6%) underwent microlaryngobronchoscopy under STRIVE Hi anesthesia. Four patients with several desaturation events required rescue oxygenation by intermittent intubation and mask bagging during the STRIVE Hi technique. However, the procedure was completed in all patients without any severe adverse effects. Overall, 15 children (51.7%) underwent supraglottoplasty, of whom 14 (93.3%) showed symptom improvement, and their postoperative weight percentile significantly increased (P=0.026). One patient required tracheostomy immediately after supraglottoplasty due to associated neurological disease.

Conclusion.

The STRIVE Hi technique is feasible for supraglottoplasty in LM patients, while type III LM patients with micrognathia or glossoptosis may have a higher risk of requiring rescue oxygenation during the STRIVE Hi technique.