Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) Use in Pediatric Populations: A Randomized Prospective Multi-Site Trial
Phase: NA
Conditions: Oxygen Deficiency, Desaturation of Blood, Hypoventilation, Anesthesia; Adverse Effect
Sponsor: Stanford University

Transnasal Humidified Rapid-Insufflation Ventilatory 
Exchange (THRIVE) Use in Pediatric Populations: A 
Randomized, Prospective Multi-Collaborative Trial  
Study Protocol  / Statistical Analysis Plan
NCT04322994 
October 8, 2020 

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Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) Use in Pediatric Populations: 
A randomized, prospective multi-collaborative trial 
Sample Size:   
500 total across 6 sites 
Study Population: 
Patients under the age of 18 years undergoing airway examinations or airway procedures with or 
without laryngoscopic suspension under general anesthesia. 
Study Design and Purpose:  
This study is a national multi-center project seeking to evaluate the efficacy of high flow nasal cannula 
(HFNC) compared to standard of care (SOC) without HFNC when delivered as part of an anesthetic plan 
in individuals undergoing microdirect laryngoscopy and bronchoscopy (MDLB).  The centers include the 
primary site - Lucile Packard Children’s Hospital (Stanford University, Palo Alto, CA), Cincinnati Children’s 
hospital (Cincinnati, OH), Lurie Children’s Hospital (Chicago, IL), UC Davis Children’s Hospital (Davis, CA). 
This is a prospective, randomized study which includes a two-parallel group design with one active 
intervention and a control group receiving standard airway management without the active 
intervention. Participants will be randomized to one of two groups at a 1:1 ratio: HFNC or SOC using a 
simple randomization procedure generated by REDCap. A total of 100 patients per site (for a total of 500 
patients) is the target enrollment.  
The purpose of the study is to determine if patients undergoing MDLB have less oxygen desaturations 
compared to those utilizing standard of care as measured by oxygen desaturation index. The secondary 
endpoints will determine if children receiving HFNC will have less desaturations below 90% and fewer 
surgical interruptions without an increase in adverse events.  
Study Duration: 
We estimate that the entire study will require 4 years, including patient recruitment, data collection, 
analysis, and report writing. 
Specific Aims and endpoints:  
Pediatric patients undergoing microdirect laryngoscopy and bronchoscopy (MDLB) pose anesthetic 
challenges of maintaining adequate oxygenation and ventilation while providing a motionless surgical 
field without an endotracheal tube. Given this challenge, we propose a prospective, randomized 
controlled trial to evaluate the use of high flow nasal cannula (HFNC) as transnasal humidified rapid-
insufflation ventilatory exchange (THRIVE) in pediatric patients undergoing MDLBs. 

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Research Questions: 
1. Can the use of HFNC during MDLB result in reduced oxygen desaturations as measured by the 
oxygen desaturation index (ODI) as compared to standard of care (SOC)? 
2. Does the use of HFNC during MDLB result in a reduced number of oxygen desaturations 
below 90% during the procedure? 
 
3. Does the use of HFNC during MDLB resulted in a reduced number of surgical interruptions? 
AIM 1:  
To prospectively determine if treatment with HFNC during MDLB reduces oxygen desaturations 
as measured by oxygen desaturation index (ODI) as compared to SOC in pediatric patients under general 
anesthesia. We hypothesize that participants receiving HFNC will demonstrate statistically improved ODI 
over participants receiving SOC. ODI is defined as a 4% decrease in saturation from a 120 second rolling 
mean for greater than 10 seconds. 
AIM 2:  
To determine if treatment with HFNC during MDLB results in a reduction in the number of 
desaturations below 90% and a reduction in the number of surgical interruptions as compared to 
standard of care in pediatric patients under general anesthesia. We hypothesize that participants 
receiving HFNC catheters will demonstrate statistically fewer desaturations over participants receiving 
SOC. Desaturations will be controlled by duration of procedure. 
Abstract:  
Maintenance of adequate oxygenation during microdirect laryngoscopy and bronchoscopy (MDLB) is 
challenging as the anesthesia provider is unable to place an endotracheal tube that would obstruct the 
surgeon’s operative field. This challenge is exacerbated in infants and young children due to their 
increased oxygen consumption and decreased functional residual capacity as compared to adults, 
resulting in a faster rate of desaturation. Moreover, given the increasing complexity of the patients with 
whom we work, these cases are increasingly more challenging. Several techniques have been described 
to optimize oxygenation and ventilation in these patients but each of these techniques has downfalls. 
The intermittent positive pressure technique, while successful in intermittently ventilating the patient, is 
associated with risk of trauma from multiple reintubations and does not provide adequate ventilation 
and oxygen during periods of apnea. The spontaneous respiration technique, while generally can 
maintain adequate oxygenation and ventilation, may not be always adequate and may lead to surgical 
interruptions from inadequate depth of anesthesia. Lastly, the jet ventilation technique carries a 
significant risk of barotrauma. In addition, none of these methods provide adequate and consistent 
monitoring of end-tidal carbon dioxide. 
High flow nasal cannula (HFNC) as transnasal humidified rapid insufflation ventilatory exchange (THRIVE) 
has been described as a successful method to deliver humidified oxygen and provide adequate 

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ventilation as an alternative to invasive airways in several populations. THRIVE has been used during 
adult procedures and to prolong apneic oxygenation in pediatrics. We introduce THRIVE as method for 
airway management in pediatric patients undergoing MDLB.  
The purpose of this multi-site, prospective, randomized controlled trial is to determine if patients 
undergoing MDLB have less desaturations compared to those utilizing SOC, as measured by oxygen 
desaturation index (ODI). The secondary aims will determine if children utilizing HFNC will have less 
desaturations below 90% and fewer surgical interruptions without an increase in adverse events. When 
novel intraoperative techniques, such as HFNC, are integrated into practice, their contribution to 
potentially reducing postoperative morbidity should be studied, as pediatric anesthesiologists redefine 
their role in the care continuum. Utilization of HFNC in this high risk patient population has the potential 
to radically transform management and improve outcomes. 
Key words: High flow nasal cannula (HFNC), transnasal humidified rapid-insufflation ventilatory 
exchange (THRIVE), oxygenation, ventilation, microlaryngoscopy and bronchoscopy 
Background:  
 
Infants and children undergoing microdirect laryngoscopy and bronchoscopy (MDLB) pose a challenge to 
anesthesia providers. Maintaining adequate oxygenation and ventilation in a spontaneously breathing 
patient without an endotracheal tube while the surgeons work in the airway often results in 
desaturation and/or the need to interrupt the procedure to oxygenate and ventilate the patient. This 
challenge is exacerbated in infants and very young children secondary to more rapid desaturation due to 
smaller functional residual capacity, a higher metabolic demand resulting in higher carbon dioxide 
generation and a greater tendency for airway collapse.1 While several techniques are utilized to help 
prevent desaturation and improve ventilation, these techniques are not without issue. Intermittent 
positive pressure ventilation administered via endotracheal tube results in multiple intubations, 
increasing the risk for trauma and apnea, with apnea leading to increased difficulty in smoothly 
continuing the procedure. While allowing the patient to maintain spontaneous respiration is idea, 
surgical interruption can occur as the anesthesia provider may be unable to maintain an adequate depth 
of anesthesia. Lastly, while jet ventilation is commonly used in adults for such procedures, the risk of 
barotrauma makes it less idea in the pediatric population. Furthermore, none of these methods provide 
consistent carbon dioxide monitoring. 
High flow nasal cannula (HFNC) delivered using the Optiflow THRIVE system (Fisher & Paykel Healthcare, 
Irvine, CA, USA) has been described as a safe, successful method to deliver humidified oxygen to 
pediatric patients.1-4 THRIVE has been used during adult procedures successfully and to prolong apneic 
oxygenation in pediatric patients.1-4 In addition, a small study published by Humphreys and colleagues in 
2017 demonstrated that THRIVE can be used safely as an oxygen delivery system in anesthesia for 
spontaneously breathing patients during spontaneous ventilation for airway procedures.2  
The purpose of this study is to further assess the use of THRIVE in pediatric patients undergoing MDLBs 
in a multi-center, randomized, prospective clinical trial to further understand the role of this oxygen 

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delivery system in pediatric anesthesia management. When a novel technology such as HFNC is 
integrated into practice, larger studies are important to better understand its role in patient care and to 
determine if it has the ability to transform management and improve outcomes. 
Preliminary Results 
HFNC has been studied in pediatrics during MDLB at a single institution (Stanford University). After IRB 
approval, patients were randomized to control or THRIVE. Controls received 100% oxygen via the side 
port of a Parson’s laryngoscope to insufflate the oropharynx at 6-10 L/min, titrated by the 
anesthesiologist. THRIVE patients received 100% oxygen via HFNC at 2L/kg/min using an Optiflow 
machine. Inclusion criteria were all patients from birth to 18 years old. Exclusion criteria included 
papillomatosis, tracheostomy, or unrepaired heart disease. 
 
The primary aim was surgical interruptions. A priori power calculation based on 15 pilot surgeries 
demonstrated the frequency of interruptions in the control to be 0.93 and 0.33 in THRIVE. Assuming a 
Poisson regression, 80% power, and 95% confidence interval, 27 patients in each group (54 total) were 
needed to demonstrate a significant difference. To account for incomplete data and dropouts, an 
additional 20 patients (74 total) were targeted for consent. The secondary aims were to compare 
differences in oxygen desaturation index (ODI), desaturations below 90%, transcutaneous carbon 
dioxide (tCO2), and adverse events. 
 
Demographics and postoperative diagnoses in control and THRIVE were collected. Interruptions were 
defined as the need to pause surgery to provide airway support, such as mask ventilation or intermittent 
intubation. Pulse oximetry was recorded by second in the electronic medical record. ODI was defined as 
a 4% decrease in saturation from a 120 second rolling mean for greater than 10 seconds. TCO2 was 
recorded at procedure start and end. Adverse events (nausea, vomiting, sinus pain, throat pain, 
epistaxis) were recorded prior to discharge. 
 
Outcomes were calculated using negative binomial regression with case duration as an offset in the 
unadjusted and adjusted models, with the exception of tCO2. Models were adjusted for postoperative 
diagnoses. 210 patients were screened and 67 (control = 36, THRIVE = 31) were included in the final 
analyses. There were no demographic group differences. P values are reported as (unadjusted value, 
adjusted value), respectively. There were no significant differences in surgical interruptions, tCO2, or 
adverse events. There were significant differences in ODI between groups (p=0.003, 0.005) and number 
of oxygen desaturations below 90% in the unadjusted model (p=0.039,0.082).  
 
This was the first prospective study examining THRIVE’s effectiveness during pediatric MDLBs. Although 
there were no significant differences in surgical interruptions, there were significant differences in ODI 
and oxygen desaturations when not adjusting for postsurgical diagnoses. Although THRIVE has been 
reported to potentially contribute to ventilation, these results do not support a difference. The table 
below summarizes these findings. 
 
 
 
 

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THRIVE vs. control 
  
  
  
  
  
β 
p-value 
  
Primary 
outcome
Number of 
Interruptions 
Unadjusted 
  
-0.70 
0.13 
  
Adjusted for post-
surgical diagnosis 
  
-0.41 
0.37 
  
  
  
  
  
  
  
  
Secondary outcomes 
ODI 
Unadjusted 
  
-1.78 
0.003 
  
Adjusted for post-
surgical diagnosis 
  
-1.74 
0.005 
  
  
  
  
  
  
  
Desaturations 
below 90% 
Unadjusted 
  
-1.25 
0.039 
  
Adjusted for post-
surgical diagnosis 
  
-1.08 
0.082 
  
  
  
  
  
  
  
Adverse Events 
Unadjusted 
  
-0.23 
0.72 
  
Adjusted for post-
surgical diagnosis 
  
-0.33 
0.64 
  
  
  
  
  
  
  
Final CO2* 
Unadjusted 
  
-1.93 
0.55 
  
Adjusted for post-
surgical diagnosis 
  
-1.04 
0.75 
  
  
 
  
  
* = linear regression result, with case duration included as a covariate in both 
unadjusted and adjusted models 
  
  
  
  
  
  
  
Summary  
Pediatric patients undergoing MDLB pose anesthetic challenges of maintaining adequate oxygenation 
and ventilation while providing motionless a motionless surgical field without an endotracheal tube. 
Given this challenge, we propose a prospective, multi-site, randomized controlled trial to evaluate HFNC 
as THRIVE in pediatric patients undergoing MDLB. 
 

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Potential benefits: 
Individual study participants may not derive direct benefit from participation in this study as we are 
studying whether the use of HFNC during MDLB can decrease the risk of oxygen desaturation. However, 
if proven successful, these patients may benefit from having decreased rates of oxygen desaturation to 
below 90% during the procedure as well as decreased number of surgical interruptions. Results from this 
study may yield new information which will contribute to a better understanding of the use of HFNC 
during ENT procedures resulting in possible changes in clinical management of subsequent patients.  
Potential risks, discomforts, inconveniences: 
Based upon preliminary data, HFNC has been utilized in over 100 patients intraoperatively during MDLB, 
including those under 2 kg without adverse effects. There have been limited reports of serious adverse 
events during its widespread and pervasive use in neonatal and pediatric intensive care units across the 
country including pneumothorax and pneumodiastinum, potentially associated with improperly sized 
nasal cannula. We will monitor patients for any adverse events during this study. In addition, 
participation in the study will not impact their clinical management as both groups of patients will 
receive the same level of anesthetic care as non-enrolled patients. Risks specific to this research are 
expected to be minimal. Adverse events will be defined using standard criteria. The researchers shall 
monitor the child while the HFNC is applied and review the child or the child’s record 1 week later. 
Serious adverse events, although unanticipated, will be addressed as follows. 
Any physical or clinical change or illness not expected after surgery will be recorded on the medical 
record chart and adverse event case report form. Recordings will include date of onset, duration, and 
the relationship to HFNC. The severity and pattern of the event, and any action taken by the study 
physician and/or outcome will also be recorded. In case of an adverse event thought to reflect HFNC, 
appropriate evaluation and management will occur. This may include a reduction in HFNC flow, 
temporary discontinuation of the HFNC, or early termination from the trial. 
Patients who experience adverse events will be monitored clinically until the event is either satisfactorily 
resolved or stabilized, as determined by the physician investigators. Actions taken and follow-up results 
will be recorded in the participant’s medical record chart and adverse event case report form. Patients 
who are discontinued from the study as a result of an adverse event will be followed with appropriate 
clinical assessments and laboratory tests until resolution. 
The principal investigator or a designee will report by telephone to the IRB all serious adverse events, 
whether or not they are deemed study-related, within 24 hours. A written report, including a full 
description of the event and any sequelae, will follow as required. An adverse experience is defined as 
serious if it meets any of the following criteria: (1) fatal, (2) life threatening (at immediate risk of death 
due to event), (3) significantly or permanently disabling, (4) requiring or prolonging in-patient 
hospitalization, (5) causing a congenital anomaly, or (6) considered to be a serious adverse event by the 
physician investigators. 

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Recruitment plan: 
Children will be identified from the operating room schedule or, for unscheduled, add-on cases, the 
coordinating anesthesiologist will contact the study team.  A member of the local study team will 
approach the families pre-operatively to explain the project and obtain consent. Once consent is 
obtained, patients will be randomized into either the usual care (control) or THRIVE (treatment) arm.    
Device Description: 
Physiological data (oxygen saturation and heart rate) will be captured real-time using the Masimo Rad-
97 Pulse Co-Oximeter (Masimo Corporation, Irvine, CA, USA). This device is FDA approved and used 
routinely in patient care, including in pediatric and neonatal populations. There is no evidence of 
harmful effects on human tissues by the utilization of this device. The device will be inspected by 
Biomedical Engineering at each site and will undergone the necessary safety tests required of all clinical 
equipment to be used in the hospital. The device will be accessed only by study staff members and the 
biomedical engineers supervising the device. It will be kept in a locked research office when not in use, 
accessible only to study staff. The investigators have received appropriate training with the equipment 
since this device is not in routine use in our hospital. 
HFNC will be provided to treatment arm patients using the Optiflow THRIVE system (Fisher & Paykel 
Healthcare, Irvine, CA, USA). This device is routinely utilized in pediatric and neonatal intensive care 
units internationally to provide high flow oxygenation. This device will be inspected by Biomedical 
Engineering and will undergone the necessary safety tests required of all clinical equipment to be used 
at the hospital.  The device will be accessed only by study staff members and the biomedical engineers 
supervising the device.  It will be kept in a locked research office when not in use, accessible only to 
study staff.  The investigators have received appropriate training with the equipment. 
Risk/Benefit Analysis: 
Those enrolled in the intervention arm will be exposed to greater than minimal risk. Potential benefits to 
the intervention arm include improved oxygenation and ventilation, improved surgical operating 
conditions, prevention of oxygen desaturation, prevention of complications related to apnea or oxygen 
desaturations, prevention of atelectasis and any subsequent complications. Potential serious risk such as 
pneumothorax or pneumocephalus are exceedingly rare and will be minimized by careful observation of 
the patients during the duration of high-flow cannula application. Potential risks such as headache, sinus 
or nasal mucosal irritation, aspiration, and gastric insufflation are also low risk with less associated 
morbidity, but the researchers feel the potential benefits outweigh these risks. The potential risks and 
benefits will be provided to the parents or guardians when obtaining written consent prior to the 
procedure. 
Methods: 
This prospective, randomized, controlled trial is a multi-center collaborative project including the 
primary site - Lucile Packard Children’s Hospital (Stanford University, Palo Alto, CA), Cincinnati Children’s 
hospital (Cincinnati, OH), Lurie Children’s Hospital (Chicago, IL), University of Virginia Children’s Hospital 

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(Charlottesville, VA), Massachusetts Eye and Ear Infirmary (Harvard University, Boston, MA), and Boston 
Children’s Hospital (Harvard University, Boston, MA).  
The primary outcome measure will be oxygen desaturation index (ODI), as defined by a 4% decrease in 
saturation from a 120 second rolling mean for greater than 10 seconds. Secondary endpoints include the 
relative number of desaturations below 90% lasting greater than2 seconds as a function of overall case 
duration and the number of surgical interruptions, as defined by any time the procedure is temporarily 
halted due to suboptimal airway conditions.  
Preoperatively, medical history will be collected along with baseline physiological data (blood pressure, 
heart rate, age, weight, gender, medical conditions, medications and allergies). The Masimo pulse 
oximeter will be applied to the patient where appropriate prior to induction of anesthesia to obtain 
baseline oxygen saturation and heart rate and will remain on the patient until the patient has emerged 
from anesthesia. The THRIVE system will be placed on patients randomized to the treatment arm 
following induction of anesthesia and prior to initiation of the procedure. It will be removed following 
completion of the procedure and prior to emergence from anesthesia. Although this may pose a 
challenge in an active infant, the team will do its best to obtain baseline data prior to induction of 
anesthesia.  
Physiological data (pulse oximeter and heart rate) will be collected real-time using the Masimo device. 
The heart rate and oxygen saturation will be continuously recorded by the Masimo device and data will 
be extracted to a research laptop via USB transfer following completion of case. The anesthesia 
monitors will record into EPIC anesthesia every 3 minutes according to anesthesia standard of care: (i) 
(non-invasively-measured) systolic/diastolic/mean arterial pressures; (ii) SaO2; (iii) heart rate; (iv) end 
tidal CO2; (v) end tidal volatile concentration and all drugs given; (vi) ventilator settings (vii) 
temperature. These vital signs will be recorded as is standard of care, but not collected by the study 
investigators, who will only gather the heart rate and oxygen saturation in two second intervals from the 
Masimo.  
The following data will also be collected: (i) medical history; (ii) type and duration of anesthesia and 
surgery; (iii) any critical or adverse events.  
Apart from placing the Masimo and THRIVE devices, the patients will receive standard care for 
anesthesia and surgery. A study personnel will remain in the operating room as an observer throughout 
the procedure. The personnel will record procedure start and end times, method of supplemental 
oxygen in the control group, and the number of surgical interruptions, defined by the need for the 
surgeon to cease the examination or operation due to suboptimal patient conditions such as 
desaturations. During procedure interruptions, the observer will record what, if any, airway intervention 
occurred, such as jaw thrust, bag mask ventilation, or intermittent intubation. Following recovery from 
anesthesia, a questionnaire regarding adverse events will be provided to applicable patients or their 
parents/guardians/representatives. 

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The THRIVE flow rate regimen will be 2 L/kg/min, maximum 70 L/min as previously described.1-3 The 
oxygen concentration will be titrated based on the surgical conditions and requirements (21 to 100% 
oxygen). 
Method of Obtaining Informed Consent: 
Children will be identified from the operating room schedule.  Parents will be provided with oral and 
written information about the research project.  The anesthesiologist for the patient will be approached 
and written consent from the parents will be obtained prior to recruitment into the study.  The surgeon 
will be notified and given oral information about the study prior to the start of the case.  If the THRIVE 
nasal cannula interferes with the safe conduct of surgery or anesthesia, then the device shall be 
removed.  While the child is under anesthesia, the parents will not have the opportunity to withdraw.  
Parents may withdraw their child after surgery.  If they withdraw from the study, we shall ask if they will 
allow us to use the collected data even if the child has withdrawn.  If not, then the data will be deleted. 
Inclusion Criteria: 
Patients meeting the following criteria will be enrolled: 
- 
Patients between the ages of 2 months and 18 years;  
- 
Patients willing and able to provide assent/parental consent to participate in the study in 
English; 
- 
Patients undergoing airway examinations or airway procedures with or without laryngoscopic 
suspension with the goal of maintaining spontaneous respiration. 
Exclusion Criteria: 
Patients will be excluded if they meet any of the following criteria: 
- 
Patients who are pregnant; 
- 
Patients with congenital cyanotic heart disease; 
- 
Patients with history of airway papillomatosis; 
- 
Patients with an absence of a parent or legal guardian who are therefore unable to provide 
appropriate consent for study participation; 
- 
Anatomical or surgical contraindications to the placement of HFNC (including but not limited to 
epistaxis, basilar skull fractures or abnormalities, facial fractures or abnormalities, nasal surgery 
or obstruction, nasal fractures, nasal vascular abnormalities); 
- 
Presence of tracheostomy; 
- 
Patients presenting for emergent surgery for which application of the HFNC may delay surgery 
or may result in increased risk of aspiration; 
- 
Patients who are intubated. 
Statistical Methods: 
Randomization: This is a prospective, randomized, multi-center, non-blinded study.  

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Data Storage: Data confidentiality will be maintained by data being stored in a password protected 
computer and hard copies of patient information stored in a locked office.  Data will be transmitted to a 
password-protected computer for further analysis. REDCap will be utilized to store de-identified data.   
Statistical analysis: This is a prospective, randomized study.   
Sample size determination: A power calculation was done by simulation.  Using data from a prior pilot 
study, the data was found to be a negative binomial distribution so a negative binomial regression was 
used.  The simulation assumed a mean for the control group of 0.119 events / minute, a theta of 0.3609 
(both from the pilot study), an average case duration of 30 minutes, and an effect size of 20% between 
the control and the experimental group.  10,000 simulations were done and a sample size of 500 (300 
per group) was determined to provide an 82% power.  The analysis was undertaken using R version 3.5.3 
(Vienna, Austria), Rstudio version 1.1.456 (Boston, MA), and the MASS package version 7.3-51.4 (New 
York City, NY) 
Blood draws: No blood draws are required for this study. 
Special considerations: Study subjects will NOT be exposed to any radiation and will NOT be exposed to 
any investigational drugs; genetic studies, discarded tissues, tissue banks, and institutional biohazard 
committee do NOT apply to this study.  Study subjects will have a non-invasive, non-radiation producing 
imaging study. 
Gender and minority inclusion: It is expected that the demographics of participants will reflect the 
overall gender and ethnic characteristics of the current clinical population. 
Randomization method: The method of randomization is simple randomization. Prior to study initiation, 
the study statistician will provide the randomization schedule through REDCap. At study conclusion, 
descriptive analyses will be conducted prior to hypothesis testing to evaluate the success of the 
randomization procedure in equally distributing patient characteristics (such as age, gender, past 
medical history, type of procedure, type of supplemental oxygen, etc.). 
Retention of patients: Retention of patients is a consideration in every study and random attrition may 
reduce statistical power. Systematic attrition threatens the external validity of the results (such as if a 
subgroup of participants tend to discontinue the study, generalizability may be compromised).  
Differential attrition may reduce validity when comparing conditions if baseline variables correlate with 
outcome. Retention will be analyzed with chi-square and life table methodology and is anticipated to be 
low. We will examine closely the enrollment of targeted patients at month 6 and 12. If, at these time 
points, we discover that the recruitment is below anticipated volume, we will immediately contact our 
colleagues at other sites. CHOP is the most likely additional sites given preliminary interests that have 
been expressed from anesthesiologists there.  
Payment:  
There is NO financial benefit or reimbursement for participation in the study. 

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References: 
1. 
Humphreys S, Lee-Archer P, Reyne G, Long D, Williams T, Schibler A: Transnasal humidified 
rapid-insufflation ventilatory exchange (THRIVE) in children: a randomized controlled trial. Br J Anaesth 
2017; 118: 232-238 
2. 
Humphreys S, Rosen D, Housden T, Taylor J, Schibler A: Nasal high-flow oxygen delivery in 
children with abnormal airways. Paediatr Anaesth 2017; 27: 616-620 
3. 
George S, Humphreys S, Williams T, Gelbart B, Chavan A, Rasmussen K, Ganeshalingham A, 
Erickson S, Ganu SS, Singhal N, Foster K, Gannon B, Gibbons K, Schlapbach LJ, Festa M, Dalziel S, Schibler 
A, Paediatric Critical Care Research Group PRiEDIC, the A, New Zealand Intensive Care Society Paediatric 
Study G: Transnasal Humidified Rapid Insufflation Ventilatory Exchange in children requiring emergent 
intubation (Kids THRIVE): a protocol for a randomised controlled trial. BMJ Open 2019; 9: e025997 
4. 
Caruso TJ, Sidell DR, Lennig M, Menendez M, Fonseca A, Rodriguez ST, Tsui B: Transnasal 
Humidified Rapid Insufflation Ventilatory Exchange (THRIVE) augments oxygenation in children with 
cyanotic heart disease during microdirect laryngoscopy and bronchoscopy. J Clin Anesth 2019; 56: 53-54