Trans-nasal Humidified Rapid Insufflation Ventilatory Exchange (THRIVE) and its Utility in Otolaryngology, Head and Neck Surgery: A Literature Review

High-flow nasal oxygen (HFNO) therapy is extensively used in critical care units for spontaneously breathing patients. Trans-nasal humidified rapid insufflation ventilatory exchange (THRIVE) is a method of apnoeic oxygenation with continuous nasal delivery of warmed, humidified oxygen at high-flow rates up to 70L/min. THRIVE extends the apnoeic window before desaturation occurs so that tubeless anaesthesia is possible. The advent of THRIVE has had a monumental impact on anaesthetic practice, with a diverse range of clinical applications and it has been incorporated into difficult airway guidelines. THRIVE has many applications in otolaryngology and head and neck surgery. It is used as a pre-oxygenation tool during induction in both anticipated and unanticipated difficult airway scenarios and as a method of oxygenation for tubeless anaesthesia in elective laryngotracheal and hypopharyngeal surgeries and during emergence from anaesthesia. In this scoping review of the literature, we aim to provide an overview on the utility of THRIVE in otolaryngology, including the underlying physiologic principles, current indications and limitations, and its feasibility and safety in different surgical contexts and specific population groups.

Transnasal Humidified Rapid Insufflation Ventilatory Exchange in Endoscopic Esophageal Surgery

OBJECTIVES

Transnasal humidified rapid insufflation ventilatory exchange (THRIVE) describes apneic oxygenation using humidified high flow nasal-cannula oxygen. Although it has been described as a sole mode of oxygenation in endoscopic laryngotracheal surgery, its use in endoscopic esophageal surgery under general anesthesia with neuromuscular paralysis has not previously been described. The objective of this study is to assess the safety and efficacy of THRIVE in esophagology.

METHODS

We conducted a retrospective review of adult patients undergoing esophageal procedures under general anesthesia who were oxygenated using THRIVE at two academic institutions. Demographic, clinical, and anesthesiologic data were collected and analyzed.

RESULTS

14 cases performed from March 2021 to March 2022 met inclusion criteria. 13/14 (92.9%) of patients were able to maintain oxygenation throughout the entirety of their procedure. The mean apneic time was 17.9 minutes with a maximum of 32 minutes. One patient required "rescue" intubation due to failure to maintain oxygenation. Excluding the sole THRIVE failure, the median SpO2 at the conclusion of surgery was 99% (range 94-100%). A linear regression model yielded an increase in EtCO2 of 0.95 mmHg/min or 0.127 kPa/min. SpO2 was negatively associated with both tobacco pack-year smoking history (R2 = 0.343, P = .014) and BMI (R2 = 0.238, P = .038).

CONCLUSION

THRIVE is a feasible, safe, and efficacious means of apneic oxygenation for patients undergoing esophageal endoscopic surgery under general anesthesia with neuromuscular paralysis, which may be particularly beneficial in patients with airway stenosis, as post-intubation changes can have severe clinical implications for this patient population. Obese patients and tobacco smokers may be at increased risk of oxygen desaturation when using THRIVE.

Trans-nasal humidified rapid insufflation ventilatory exchange (THRIVE) in neuroanesthesia practice: A review

Respiratory management is an important aspect of care in neuroanesthesia practice for neurosurgical patients. A wide variety of procedures are performed under sedation in the neurosurgical population, and maintaining oxygenation is of paramount importance during these procedures. The high-flow oxygen devices improve arterial oxygenation by providing higher inspiratory oxygen concentration and maintaining higher dynamic positive airway pressure. These devices have gained importance during the recent years with regard to enhancing patient safety. This narrative review focuses on the role of trans-nasal humidified rapid insufflation ventilatory exchange (THRIVE) and high-flow nasal oxygenation (HFNO) techniques in the neuroanesthesia practice and electroconvulsive therapy.

Safety and Utility of Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) for Laser Laryngeal Surgery

OBJECTIVE

Transnasal humidified rapid-insufflation ventilatory exchange (THRIVE) is gaining acceptance as a safe method for apneic ventilation and oxygenation during laryngeal procedures, but remains controversial during laser laryngeal surgery (LLS) due to the theoretical risk of airway fire. This study describes our experience with THRIVE during LLS.

STUDY DESIGN

Retrospective cohort study.

SETTING

Stanford University Hospital, October 15, 2015 to June 1, 2021.

METHODS

Retrospective chart review of patients ≥18 years who underwent LLS involving the CO2 or KTP laser with THRIVE as the primary mode of oxygenation.

RESULTS

A total of 172 cases were identified. 20.9% were obese (BMI ≥ 30). Most common operative indication was subglottic stenosis. The CO2 laser was used in 79.1% of cases. Median lowest intraoperative SpO2 was 96%. 44.7% cases were solely under THRIVE while 16.3% required a single intubation and 19.2% required multiple intubations. Mean apnea time for THRIVE only cases was 32.1 minutes and in cases requiring at least one intubation 24.0 minutes (p < .001). Mean apnea time was significantly lower for patients who were obese (p < .001) or had a diagnosis of hypertension (p = .016). Obese patients and patients with hypertension were 2.03 and 1.43 times more likely to require intraoperative intubation, respectively. There were no intraoperative complications or fires since the institution of our LLS safety protocol.

CONCLUSION

By eliminating the fuel component of the fire triangle, THRIVE can be safely used for continuous delivery of high FiO2 during LLS, provided adherence to institutional THRIVE-LLS protocols.

The effect of intraoperative transnasal humidified rapid-insufflation ventilatory exchange on emergence from general anesthesia in patients undergoing microlaryngeal surgery: a randomized controlled trial

BACKGROUND

Transnasal humidified rapid-insufflation ventilatory exchange (THRIVE) has received extensive attention for its utility in tubeless anesthesia. Still, the effects of its carbon dioxide accumulation on emergence from anesthesia have not been reported. This randomized controlled trial aimed at exploring the impact of THRIVE combined with laryngeal mask (LM) on the quality of emergence in patients undergoing microlaryngeal surgery.

METHODS

After research ethics board approval, 40 eligible patients receiving elective microlaryngeal vocal cord polypectomy were randomly allocated 1:1 to two groups, THRIVE + LM group: intraoperative apneic oxygenation using THRIVE followed by mechanical ventilation through a laryngeal mask in the post-anesthesia care unit (PACU), or MV + ETT group: mechanically ventilated through an endotracheal tube for both intraoperative and post-anesthesia periods. The primary outcome was duration of PACU stay. Other parameters reflecting quality of emergence and carbon dioxide accumulation were also recorded.

RESULTS

Duration of PACU stay (22.4 ± 6.4 vs. 28.9 ± 8.8 min, p = 0.011) was shorter in the THRIVE + LM group. The incidence of cough (2/20, 10% vs. 19/20, 95%, P < 0.001) was significantly lower in the THRIVE + LM group. Peripheral arterial oxygen saturation and mean arterial pressure during intraoperative and PACU stay, Quality of Recovery Item 40 total score at one day after surgery and Voice Handicap Index-10 score at seven days after surgery were of no difference between two groups.

CONCLUSIONS

The THRIVE + LM strategy could accelerate emergence from anesthesia and reduce the incidence of cough without compromising oxygenation. However, these benefits did not convert to the QoR-40 and VHI-10 scores improvement.

TRIAL REGISTRATION

ChiCTR2000038652.

Apneic anesthesia with THRIVE for pediatric bronchial foreign body removal: A case series

Anesthesia for impacted tracheobronchial foreign body (FB) removal in pediatrics is challenging owing to shared airway, need of tubeless apneic anesthesia, and higher risk of airway complications. Transnasal humidified rapid insufflation ventilatory exchange (THRIVE) has unique applications for apneic anesthesia. The authors describe two pediatric cases of impacted lower bronchial FB that were difficult to retrieve and required long procedure time. They were done successfully under apneic anesthesia using THRIVE that provided intermittent total apnea of 58 and 62 min, respectively, with single-continuous apnea time of 13-18 min. THRIVE facilitated the procedure by providing a safe long apnea time without desaturation and with permissible increase in PaCo2 while maintaining hemodynamic parameters and oxygenation.

Microlaryngeal Laser Surgery Using High-flow Nasal Ventilation at Two Oxygen Concentration Deliveries

OBJECTIVES

Ventilation using 100% oxygenation creates a risk of fire during laser microlaryngeal surgery (MLS). The purpose of this study is to describe the technique of transnasal high-flow ventilation using laser safe (30%) oxygen conditions, measure the intraoperative real-time laryngeal oxygen concentration, and examine patient saturation status using this technique.

METHODS

Prospective IRB approved study of patients undergoing tubeless laser MLS using high-flow nasal oxygenation. Delivered oxygen concentration was reduced from 100% to 30% before lasering using an oxygen-air blender then increased to 100% post-laser procedure. Outcome measures included time for laryngeal oxygen concentration to equalize to laser safe levels; time to, methods of and duration of rescue ventilation; and desaturation rates and apnoeic times at both 100% and 30% oxygen deliveries.

RESULTS

Fifty patients were recruited (mean age = 47.4 years). Mean laryngeal oxygen concentration (%) at 100% and 30% deliveries was 98.46 and 31.45, respectively. Mean (SD) of laryngeal oxygen concentration equalization time to 30% (seconds) was 9.4 (3.69). At 30% oxygen delivery desaturation rate was faster and apneic time shorter compared with 100%. Eighteen patients required rescue (jet) ventilation and they had a faster apneic desaturation rate (%/minute) than patients not requiring rescue. Mean (SD) apneic time (minutes) at 30% delivery was 4.56 (2.25) and 4.41 (2.18) in rescue versus non-rescue groups respectively. BMI was the only significant predictor of desaturation rate at 30% oxygen delivery.

CONCLUSION

It is possible to achieve a safe time window for use of laser during MLS using transnasal humidified high-flow ventilation by delivering 30% oxygen concentration.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:634-639, 2023.

Apnoeic oxygenation in morbid obesity: a randomised controlled trial comparing facemask and high-flow nasal oxygen delivery

BACKGROUND

Obesity is a risk factor for airway-related incidents during anaesthesia. High-flow nasal oxygen has been advocated to improve safety in high-risk groups, but its effectiveness in the obese population is uncertain. This study compared the effect of high-flow nasal oxygen and low-flow facemask oxygen delivery on duration of apnoea in morbidly obese patients.

METHODS

Morbidly obese patients undergoing bariatric surgery were randomly allocated to receive either high-flow nasal (70 L min^-1) or facemask (15 L min^-1) oxygen. After induction of anaesthesia, the patients were apnoeic for 18 min or until peripheral oxygen saturation decreased to 92%.

RESULTS

Eighty patients were studied (41 High-Flow Nasal Oxygen, 39 Facemask). The median apnoea time was 18 min in both the High-Flow Nasal Oxygen (IQR 18-18 min) and the Facemask (inter-quartile range [IQR], 4.1-18 min) groups. Five patients in the High-Flow Nasal Oxygen group and 14 patients in the Facemask group desaturated to 92% within 18 min. The risk of desaturation was significantly lower in the High-Flow Nasal Oxygen group (hazard ratio=0.27; 95% confidence interval [CI], 0.11-0.65; P=0.007).

CONCLUSIONS

In experienced hands, apnoeic oxygenation is possible in morbidly obese patients, and oxygen desaturation did not occur for 18 min in the majority of patients, whether oxygen delivery was high-flow nasal or low-flow facemask. High-flow nasal oxygen may reduce desaturation risk compared with facemask oxygen. Desaturation risk is a more clinically relevant outcome than duration of apnoea. Individual physiological factors are likely to be the primary determinant of risk rather than method of oxygen delivery.

CLINICAL TRIAL REGISTRATION

NCT03428256.

Subglottic tracheal stenosis complicating pregnancy: A case report

The case presented details an uncommon case of subglottic tracheal stenosis exacerbated by pregnancy. We outine the multidisciplinary management involved and the outcomes for the pregnancy. The case serves as a reminder that shortness of breath in pregnancy has a broad differential diagnosis, and stridor is always abnormal.

Feasibility and safety of THRIVE in transoral laser microsurgery

OBJECTIVE

Transnasal Humidified Rapid Insufflation Ventilatory Exchange (THRIVE) presents obvious advantage in laryngeal surgery and Transoral Laser Microsurgery (TLM). Airway fire represents a rare complication of TLM and may be the most important limitation in the use of THRIVE. The objective was to evaluate the different operating conditions of the TLM with THRIVE with regard to fire risk.

EXPERIMENT

In this report, we assessed the risk of fire by varying the Fraction of Inspired Oxygen (FiO2), the Laser Energy, and the placement of endolaryngeal surgical and ventilatory equipment in a porcine model for TLM.

RESULTS

Fire, sparks and smoke were reported. No combustion occurred with THRIVE in the absence of an endolaryngeal material. Fire occurred systematically while delivering between 3 and 5 W Carbon dioxide (CO2) Laser direct shot on a dry laryngeal cotton. Conclusion THRIVE-TLM should never be performed using a dry cotton or a plastic endolaryngeal material.

Trans-nasal Humidified Rapid Insufflation Ventilatory Exchange (THRIVE) ventilation during electroconvulsive therapy (ECT) for a pregnant patient- A novel technique

Maintaining oxygenation and ventilation is imperative in a pregnant patient undergoing electroconvulsive therapy (ECT). Here, we present the successful utilization of Trans-nasal Humidified Rapid Insufflation Ventilatory Exchange (THRIVE) in a six-month pregnant patient who received ECT under general anesthesia.

Tracheal Extubation Under Deep Anesthesia Using Transnasal Humidified Rapid Insufflation Ventilatory Exchange vs. Awake Extubation: An Open-Labeled Randomized Controlled Trial

Background

Tracheal extubation can be associated with several complications, including desaturation, agitation, hypertension, and tachycardia. We hypothesize that the use of transnasal humidified rapid insufflation ventilator exchange (THRIVE) immediately after extubation under deep anesthesia reduces the incidence of these adverse events.

Methods

One hundred patients who underwent elective abdominal surgery under general anesthesia were randomly assigned to undergo tracheal extubation under deep anesthesia employing THRIVE (THRIVE group) or awake extubation (CONTROL group). The primary outcome was the incidence of experiencing desaturation (SpO₂ < 90%) at any time during emergence from anesthesia. Secondary outcomes included variations in heart rate and blood pressure, comfort level, bucking, and agitation.

Results

The THRIVE group showed a lower incidence of desaturation than the CONTROL group (12 vs. 54%, OR = 0.22 [95% CI, 0.10-0.49], P < 0.001). Less patients in the THRIVE group experienced a 20% (or more) increase in mean arterial pressure (4 vs. 26%, OR = 0.15 [95% CI, 0.04-0.65], P = 0.002). THRIVE patients did not suffer from agitation or bucking, while in the CONTROL group agitation and bucking occurred in 22 and 58% of the patients, respectively. Additionally, the THRIVE group showed a lower incidence of uncomfortable experience than the CONTROL group (8 vs. 36%, OR = 0.22 [95% CI, 0.08-0.61], P = 0.001).

Conclusion

Tracheal extubation under deep anesthesia using THRIVE decreases the incidence of desaturation and adverse haemodynamic events and increases patient satisfaction. Extubation under deep anesthesia using THRIVE might be an alternative strategy in selected patient populations.

Cohort study of THRIVE predicting adverse outcomes in acute ischemic stroke of the anterior circulation and posterior circulation after 3 months and 1 year of follow-up

PURPOSE

To evaluate the difference of Totaled Health Risks In Vascular Events (THRIVE) in predicting adverse outcomes in acute ischemic stroke (AIS) of the anterior circulation and posterior circulation at 3-month and 1-year follow-up.

METHODS

A total of 858 patients with AIS were followed up for 3 months and 1 year, and their data prospectively collected. The occurrence of death or moderate to severe disability (modified Rankin Scale ≥ 3 points) was regarded as the endpoint. MedCalc software was used to create the THRIVE receiver operating characteristic curve. The area under the curve (AUC) was calculated to compare the THRIVE scale in predicting adverse outcomes in AIS of the anterior and posterior circulation and compare the differences.

RESULTS

At 3-month follow-up, the AUC of THRIVE was 0.685 (95% CI 0.644-0.724) for AIS of the anterior circulation and 0.709 (95% CI 0.647-0.765) for AIS of the posterior circulation. The area difference between them was 0.0235 (95% CI -0.0728-0.120, P = 0.6330[>0.05]). The AUC of THRIVE for AIS in the anterior circulation at 1 year was 0.701 (95% CI 0.660-0.740), and that for AIS in the posterior circulation at 1 year was 0.747 (95% CI 0.687-0.800). The area difference between them was 0.0458 (95% CI -0.0489-0.140, P = 0.3436 [>0.05]). The difference was not statistically significant.

CONCLUSION

THRIVE can well predict the short-term and long-term adverse prognosis of AIS in the anterior and posterior circulation and has the same predictive effect.

The effect of transnasal humidified rapid-insufflation ventilator exchange (THRIVE) versus nasal prongs on safe apnoea time in paralysed obese patients: a randomised controlled trial

BACKGROUND

Evidence is lacking regarding the efficacy of Optiflow transnasal humidified rapid-insufflation ventilator exchange (THRIVE™) in obese patients. We compared the impact of this technique at 70 L min^-1 with 4 L min^-1 oxygen via nasal prongs on safe apnoea times of paralysed obese patients.

METHODS

We randomised adults with a BMI >35 kg m^-2 undergoing elective bariatric surgery. While apnoeic and paralysed, Group T received 70 L min^-1 oxygen via Optiflow THRIVE™. Group N received nasal prong oxygen at 4 L min^-1. The primary outcome was time to SpO₂ ≤95% while apnoeic, with a 360 s cut-off. This was analysed by applying a time-to-event analysis.

RESULTS

Forty-two patients were included. The median (inter-quartile range) BMI was 44.8 kg m^-2 (40.0-50.0) in Group T and 42.0 kg m^-2 (39.3-45.1) in Group N. Median (inter-quartile range) time to SpO₂ ≤95% in Group T was 356 (165 to ≥360) s and in Group N, 210 (160-270) s. Using a survival analysis framework, median time-to-event in Group T was 356 s (95% confidence interval 165 s-upper limit not defined) and 210 s (95% confidence interval 160-242 s) (P=0.049) in Group N.

CONCLUSIONS

Compared with oxygen delivered via nasal prongs at 4 L min^-1, oxygen delivery via Optiflow THRIVE™ at a flow rate of 70 L min^-1 can prolong safe apnoea time, however, the results are statistically inconclusive. Optiflow THRIVE™ did decrease the rate of reduction in Pa_o2 during apnoea.

CLINICAL TRIAL REGISTRATION

ANZCTR 12618000445279.

Biomarkers for oxidative stress and organ injury during Transnasal Humidified Rapid-Insufflation Ventilatory Exchange compared to mechanical ventilation in adults undergoing microlaryngoscopy: A randomised controlled study

BACKGROUND

Apnoeic oxygenation using Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) during general anaesthesia prolongs the safe apnoeic period. However, there is a gap of knowledge how THRIVE-induced hyperoxia and hypercapnia impact vital organs. The primary aim of this randomised controlled trial was to characterise oxidative stress and, secondary, vital organ function biomarkers during THRIVE compared to mechanical ventilation (MV).

METHODS

Thirty adult patients, American Society of Anesthesiologists (ASA) 1-2, undergoing short laryngeal surgery under general anaesthesia were randomised to THRIVE, F_I O₂ 1.0, 70 L min^-1 during apnoea or MV. Blood biomarkers for oxidative stress, malondialdehyde and TAC and vital organ function were collected (A) preoperatively, (B) at procedure completion and (C) at PACU discharge.

RESULTS

Mean apnoea time was 17.9 (4.8) min and intubation to end-of-surgery time was 28.1 (12.8) min in the THRIVE and MV group, respectively. Malondialdehyde increased from 11.2 (3.1) to 12.7 (3.1) µM (P = .02) and from 9.5 (2.2) to 11.6 (2.6) µM (P = .003) (A to C) in the THRIVE and MV group, respectively. S100B increased from 0.05 (0.02) to 0.06 (0.02) µg L^-1 (P = .005) (A to C) in the THRIVE group. No increase in TAC, CRP, leukocyte count, troponin-T, NTproBNP, creatinine, eGFRcrea or NSE was demonstrated during THRIVE.

CONCLUSION

While THRIVE and MV was associated with increased oxidative stress, we found no change in cardiac, inflammation or kidney biomarkers during THRIVE. Further evaluation of stress and inflammatory response and cerebral and cardiac function during THRIVE is needed.

THIRVE in Foreign Body Bronchus Removal-A Novel Approach

We prospectively studied novel anesthetic and surgical approach to foreign body bronchus removal using HHFNC (heated humidified high flow nasal cannula)/THRIVE technique(Transnasal Humidified Rapid-Insufflation ventilatory Exchange) in eleven cases. MacIntosh Laryngoscope was used to expose laryngeal inlet and FB was removed with an optical forcep (mounted over 2.7 mm rigid bronchoscope) without using ventilating bronchosocope. Total intravenous anaesthesia (TIVA) was given in all cases. FB was removed completely in all eleven cases. The average duration of procedure was 4.5 min. HHFNC improved the apnoea time with 6 min as maximum procedure time. Induction with Fentanyl, Intermittent Propofol injection and succinylcholine prevented excessive coughing, irritation, movement of the patient, vocal cords and posterior tracheal wall. Time management during this novel approach is crucial starting from removal of FB and check bronchoscopy.

Validation and comparison of prognostic scales in Chinese patients with ischemic stroke: a prospective study from CATIS

BACKGROUND

: Various tools are currently available to quantify the risks of adverse clinical outcomes after an ischemic stroke. This study aimed to validate and compare prognostic scales among Chinese patients with ischemic stroke.

METHODS

: We compared three stroke prognostic scales (Stroke Prognostication using Age and the National Institutes of Health Stroke Scale-100 [SPAN-100], Totaled Health Risks in Vascular Events [THRIVE], and Acute Stroke Registry and Analysis of Lausanne [ASTRAL]) in 3870 Chinese patients with ischemic stroke from the China Antihypertensive Trial in Acute Ischemic Stroke (CATIS). The 2-year primary outcome was a combination of death and major disability (modified Rankin Scale score ≥3).

RESULTS

: Among all the scales, the ASTRAL score had the best accuracy for predicting 2-year prognosis in Chinese patients with ischemic stroke. The C-statistic of the ASTRAL score for the 2-year primary outcome was 0.79 (95% confidence interval [CI]: 0.78-0.80), and the Hosmer-Lemeshow goodness-of-fit test showed that the ASTRAL score fitted Chinese patients with ischemic stroke well (χ² = 9.83, P = 0.277). The incidences of the primary outcome in the <5%, 5%-9.9%, 10%-19.9%, and ≥20% risk groups based on the ASTRAL scores were 3.93%, 7.55%, 14.29%, and 41.81%, respectively (odds ratio: 1.23; 95% CI: 1.21-1.26; P < 0.001).

CONCLUSION

: The ASTRAL score had higher efficacy than the SPAN-100 and THRIVE scores in predicting 2-year adverse outcomes among Chinese patients with ischemic stroke, suggesting that it could be a valuable risk assessment tool for the 2-year prognosis of such patients.

New Visionary in Upper Airway Surgeries-THRIVE, a Tubeless Ventilation

THRIVE stands for Transnasal Humidified Rapid Insufflation Ventilatory Exchange. Usage of THRIVE technique is common in emergency settings and of late its usage in upper airway surgeries is gaining popularity. (1) To determine the operative time, total anaesthesia time, safety and efficacy of THRIVE in patients undergoing upper airway surgeries for varied pathologies. (2) To assess the surgeon's satisfaction and patients post-operative comfort. An observational study was from May 2019 to Oct 2020. Study was conducted through a detailed proforma which consists of patient demographic details, physical status, co-morbidities and various domains to assess the safety and efficacy of THRIVE. A total of 32 patients were divided into four groups depending on the type of surgery. We had 18 patients in microlaryngeal excision, six in direct laryngoscopy and biopsy, four in tracheostomy and four in balloon dilatation for subglottic stenosis groups. The mean operation time was 16 ± 2 min in the first three groups and 29 ± 0.8 in the fourth group. All the patients underwent successful surgeries without any episodes of desaturation, without complications and with good surgical satisfaction. THRIVE with appropriate safety precautions can be tried in patients undergoing various upper airway surgeries of short duration. All the patients in our study maintained stable vital parameters throughout the surgery. Initial results with the use of THRIVE as per our study and other studies are definitely encouraging to use THRIVE in upper airway surgeries with varied pathologies.

Transnasal humidified rapid-insufflation ventilatory exchange during rapid sequence induction in children

BACKGROUND

The objective of this study was to measure the incidence of arterial oxygen desaturation during rapid sequence induction intubation in children following apnoeic oxygenation via transnasal humidified rapid-insufflation ventilatory exchange (THRIVE).

METHODS

In this prospective observational study, arterial desaturation < 95% SaO₂ before intubation was recorded following apnoeic RSI combining an intravenous hypnotic agent, suxamethonium and THRIVE (used during the apnoeic period). The incidence of desaturation was calculated in the whole cohort and according to patients' age (older or younger than 1 year).

RESULTS

Complete data were collected for 79 patients, 1 day to 15 years of age. Nine patients (11.4%) exhibited arterial desaturation before tracheal intubation and received active facemask ventilation. Patients exhibiting desaturation were more likely to be less than 1 year of age (9/9, (100%) versus 37/70, (52.9%); P = 0.005), to be reported as difficult intubations (5/9, (55.6%) versus 1/70, (1.4%), p < 0.001), and to have regurgitation at induction (2/9, (22.2%) versus 0/70, (0%), p = 0.01).

CONCLUSIONS

Results of the current study indicated that almost 91% of RSI can be performed without desaturation when THRIVE is used. A comparative controlled study is required to confirm these findings. Specific situations and conditions limiting the efficacy of THRIVE during RSI should also be investigated.

A comparison of gastric gas volumes measured by computed tomography after high-flow nasal oxygen therapy or conventional facemask ventilation. Anaesthesia 2021;76:1184-1189. [PMID: 33651914 DOI: 10.1111/anae.15433]

High-flow nasal oxygen therapy is increasingly used to improve peri-intubation oxygenation. However, it is unknown whether it may cause or exacerbate insufflation of gas into the stomach. High-flow nasal oxygen therapy is now standard practice in our hospital for adult patients undergoing percutaneous thermal ablation of liver cancer under general anaesthesia with tracheal intubation. We compared gastric gas volumes measured from computed tomography images that had been acquired immediately after intubation in two series of patients: 50 received peri-intubation high-flow nasal oxygen therapy and another 50 received conventional facemask pre-oxygenation and ventilation before intubation and before high-flow nasal oxygen therapy became standard practice in our unit. Median (IQR [range]) gastric gas volume was 24.0 (14.2-59.9 [3-167]) cm³ in the high-flow nasal oxygen therapy group and 23.8 (12.6-38.8 [0-185]) cm³ in the facemask group. There was no difference between the two groups in the volume of gastric gas measured by computed tomography imaging (Mann-Whitney U-test, U = 1136, p = 0.432, n₁  = n₂  = 50). Our results demonstrate that a small volume of gastric gas is commonly present after induction of anaesthesia, but that the use of peri-intubation high-flow nasal oxygen therapy for pre-oxygenation and during apnoea does not increase this volume compared with conventional facemask pre-oxygenation and ventilation. This is clinically relevant, as high-flow nasal oxygen therapy is increasingly being used in a peri-intubation context and in patients at higher risk of aspiration.

Transnasal Humidified Rapid Insufflation Ventilatory Exchange With Nasopharyngeal Airway Facilitates Apneic Oxygenation: A Randomized Clinical Noninferiority Trial

Background: Transnasal humidified rapid insufflation ventilatory exchange (THRIVE) was used to extend the safe apnea time. However, THRIVE is only effective in patients with airway opening. Nasopharyngeal airway (NPA) is a simple device that can help to keep airway opening. This study aimed to investigate the noninferiority of NPA to jaw thrust for airway opening during anesthesia-induced apnea. Methods: This was a prospective randomized single-blinded noninferiority clinical trial on the use of THRIVE in patients with anesthesia-induced apnea. The participants were randomly allocated to receive NPA or jaw thrust. The primary outcomes were PaO₂ and PaCO₂ at 20 min after apnea, with noninferiority margin criteria of -6.67 and 0.67 kPa, respectively. Results: A total of 123 patients completed the trial: 61 in the NPA group and 62 in the jaw thrust group. PaO₂ at 20 min after apnea was 42.9 ± 14.0 kPa in the NPA group and 42.7 ± 13.6 kPa in the jaw thrust group. The difference between these two means was 0.25 kPa (95% CI, -3.87 to 4.37 kPa). Since the lower boundary of the 95% CI was > -6.67 kPa, noninferiority was established because higher PO₂ is better. PaCO₂ at 20 min after apnea was 10.74 ± 1.09 kPa in the NPA group and 10.54 ± 1.18 kPa in the jaw thrust group. The difference between the two means was 0.19 kPa (95% CI, -0.14 to 0.53 kPa). Since the upper boundary of the 95% CI was <0.67 kPa, noninferiority was established because lower PCO₂ is better. No patient had a SpO₂ < 90% during apnea. Conclusion: When THRIVE was applied during anesthesia-induced apnea, NPA placement kept airway opening and was noninferior to jaw thrust in terms of its effects on PaO₂ and PaCO₂ at 20 min after apnea. Clinical Trial Registration: ClinicalTrials.gov (NCT03741998).

New technique: the use of the THRIVE sequence in the follow-up of patients who received endovascular intracranial aneurysm treatment

PURPOSE

To determine the diagnostic accuracy of 3D time of flight MR angiography (TOF-MRA), contrast enhanced MR angiography (CE-MRA), and T1-weighted high-resolution isotropic volume examination (THRIVE) at 3 T for the evaluation of intracranial aneurysm occlusion after endovascular treatment and to evaluate the usability of the THRIVE sequence in endovascular treatment follow-up.

METHODS

In 3 T MR follow-up examinations of 66 aneurysms in 50 patients treated endovascularly, 3D TOF-MRA (index test), THRIVE (index test), and CE-MRA (reference standard) examinations were performed in a retrospective consecutive case series. Source images were classified as class 1, class 2, and class 3 according to the Raymond criteria using MIP (maximum intensity projection) techniques. The compatibility between sequences was evaluated with the Kappa test. The sensitivity and specificity were also calculated.

RESULTS

In the evaluation of THRIVE and CE-MRA sequences, compatibility was determined in 61 cases in total, with an overall fit of 61/66 (92.42%). A statistically significant correlation was found between THRIVE and CE-MRA (p < 0.001, κ = 0.800). In the evaluation of TOF and CE-MRA sequences, compatibility was determined in 54 cases in total, and the overall fit was 54/66 (81.8%). A statistically significant agreement was found between TOF and CE-MRA (p < 0.001, κ = 0.502). Assuming that CE-MRA is a reference standard, the sensitivity and specificity of the TOF sequence were 44.4% and 97.9%, respectively, and the sensitivity and specificity of the THRIVE sequence were 77.8% and 97.9%, respectively.

CONCLUSION

The THRIVE sequence can be used as a noncontrast method for monitoring endovascularly treated intracranial aneurysms.

Apnoeic oxygenation in paediatric anaesthesia: a narrative review

Apnoeic oxygenation refers to oxygenation in the absence of any patient or ventilator effort to move the lungs. This phenomenon was first described in humans in the mid-20th century but has seen renewed interest in the last decade following the demonstration of apnoeic oxygenation with low-flow, and subsequently high-flow, nasal oxygen. This narrative review summarises our understanding of apnoeic oxygenation in the paediatric population. We examine the evidence supporting oxygenation via tracheal tube, modified laryngoscopes and nasal cannulae. The evidence for prolongation of safe apnoea time at induction of anaesthesia is also appraised. We explore the capacity for carbon dioxide clearance, flow rate selection with high-flow nasal oxygen and complications associated with the technique. It remains uncertain whether apnoeic oxygenation in paediatric patients results in a meaningful clinical benefit compared with standard care for outcomes such as the number of tracheal intubation attempts or the incidence of hypoxaemia. In particular, the role of apnoeic oxygenation in paediatric difficult airway management is unclear as this has not been the targeted focus of any published research to date.

Utility of Transnasal Humidified Rapid Insufflation Ventilatory Exchange for Microlaryngeal Surgery

OBJECTIVE

Microlaryngeal surgery typically requires oxygenation and ventilation via either an endotracheal tube (ETT), jet ventilation (JV), or intermittent apnea with an ETT. Transnasal Humidified Rapid Insufflation Ventilatory Exchange (THRIVE) delivered by high flow nasal cannula has been reported as an alternative technique. This method of apneic oxygenation and ventilation allows for stable, unobstructed visualization of immobile laryngeal structures. We aim to describe the technique and characterize intraoperative parameters related to its safety.

STUDY DESIGN

Case Series.

METHODS

The electronic medical record was reviewed for patients who underwent microlaryngoscopy using THRIVE technique. Patient demographics, procedural details, operative parameters, and anesthesia records were reviewed. Descriptive statistics were reported.

RESULTS

A total of 53 patients underwent microlaryngoscopy using THRIVE as the sole method of ventilation, with 62% female. Median age was 51 years, and median BMI was 25 kg/m² . Most patients were ASA class 2, and most had a Mallampati score of 2. The most common surgical indications were subglottic stenosis, vocal fold lesions, and vocal fold paralysis. Median apnea time was 16 minutes. At the end of case, median end tidal CO₂ was 50 mmHg, and median minimum SpO₂ was 95. Six cases required supplementation of THRIVE with JV or tracheal intubation for sustained oxygen desaturation. There was an increase in end tidal CO₂ of 0.844 mmHg/min of apneic time.

CONCLUSIONS

THRIVE is a safe and effective technique for oxygenation and ventilation in microlaryngeal, non-laser surgery in appropriately selected patients. To ensure safety, back-up plans such as jet ventilation and microlaryngeal ETT should be available.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:587-591, 2021.

High Flow Nasal Cannula: A Game Changer in Airway Surgery

High flow nasal cannula (HFNC) delivers humidified oxygen at high flow. Its use during airway procedures has many advantages. The study was done to determine the duration of apnea time, safety and compatibility with laser, while using HFNC during airway procedures. A prospective study was done at a tertiary care hospital between March 2017 and August 2017 on 16 patients. HFNC was used during airway surgeries for various pathologies. There were 11 males and 5 females. The patient age ranged from 4 days to 28 years. HFNC provided an unobstructed view of the surgical field, laser could be used safely, there was an increase in the apnea window, and post-operative symptoms like throat irritation and cough were infrequent. Usage of HFNC provides an unobstructed view of the surgical field and reduces post-operative discomfort. It helps in difficult airway situations by optimizing oxygenation and increasing the apnea time.

A physiological study to determine the mechanism of carbon dioxide clearance during apnoea when using transnasal humidified rapid insufflation ventilatory exchange (THRIVE)

Clinical observations suggest that compared with standard apnoeic oxygenation, transnasal humidified rapid‐insufflation ventilatory exchange using high‐flow nasal oxygenation reduces the rate of carbon dioxide accumulation in patients who are anaesthetised and apnoeic. This suggests that active gas exchange takes place, but the mechanisms by which it may occur have not been described. We used three laboratory airway models to investigate mechanisms of carbon dioxide clearance in apnoeic patients. We determined flow patterns using particle image velocimetry in a two‐dimensional model using particle‐seeded fluorescent solution; visualised gas clearance in a three‐dimensional printed trachea model in air; and measured intra‐tracheal turbulence levels and carbon dioxide clearance rates using a three‐dimensional printed model in air mounted on a lung simulator. Cardiogenic oscillations were simulated in all experiments. The visualisation experiments indicated that gaseous mixing was occurring in the trachea. With no cardiogenic oscillations applied, mean (SD) carbon dioxide clearance increased from 0.29 (0.04) ml.min⁻¹ to 1.34 (0.14) ml.min⁻¹ as the transnasal humidified rapid‐insufflation ventilatory exchange flow rate was increased from 20 l.min⁻¹ to 70 l.min⁻¹ (p = 0.0001). With a cardiogenic oscillation of 20 ml.beat⁻¹ applied, carbon dioxide clearance increased from 11.9 (0.50) ml.min⁻¹ to 17.4 (1.2) ml.min⁻¹ as the transnasal humidified rapid‐insufflation ventilatory exchange flow rate was increased from 20 l.min⁻¹ to 70 l.min⁻¹ (p = 0.0014). These findings suggest that enhanced carbon dioxide clearance observed under apnoeic conditions with transnasal humidified rapid‐insufflation ventilatory exchange, as compared with classical apnoeic oxygenation, may be explained by an interaction between entrained and highly turbulent supraglottic flow vortices created by high‐flow nasal oxygen and cardiogenic oscillations.