The Videolaryngoscopy in Small Infants (VISI) Trial
Phase: NA
Conditions: Surgery, Anesthesia, Endotracheal
Sponsor: Children's Hospital of Philadelphia

 
Title: 
The Videolaryngoscopy in Small Infants (VISI) Trial 
Short Title 
VISI 
 
Drug or Device 
Name(s): 
Storz C-MAC Video Laryngoscope and 
Standard Direct Laryngoscope 
eIRB Number 
17-014302 
 
Protocol Date: 
February 28, 2018        Version 2.0 
 
Sponsor: 
 
 
Anesthesia Patient Safety Foundation (APSF)              
 
 
 
 
 
Amendment 1 Date: May 3, 2018 
 
Amendment 3 Date: 
Amendment 2 Date: July 31, 2018 
 
Amendment 4 Date: 
 
 
 
 
 
 
 
 
 
 
 
Study and Site Principal Investigator 
John Fiadjoe M.D. 
The Children’s Hospital of Philadelphia 
3401 Civic Center Blvd 
Philadelphia, PA, 19104 
Phone (215) 590-3916 
email: fiadjoej@email.chop.edu 
 
 

 
 
 
 
 
 
 
 
 
 
ii
SITE INVESTIGATORS SIGNATURE PAGE 
Protocol Title 
The Videolaryngoscopy in Small Infants (VISI) Trial 
Short Title 
VISI 
Lead Investigator 
Academic Affiliation 
 
Protocol Version 
Version 2.0 
Version Date 
July 31, 2018 
 
I conﬁrm that I have read this protocol, I understand it, and I will conduct the study 
according to the protocol. I will also work consistently with the ethical principles that have 
their origin in the Declaration of Helsinki and will adhere to the Ethical and Regulatory 
Considerations as stated. I conﬁrm that if I or any of my staﬀ are members of the 
Institutional Review Board, we will abstain from voting on this protocol, its future renewals, 
and its future amendments.  
 
Site Principal Investigator Name 
 
Site Principal Investigator Signature 
 
Date: 
 
 
 
 

 
 
 
 
 
 
 
 
 
 
iii
TABLE OF CONTENTS 
Table of Contents .................................................................................................................. iii 
Abbreviations and Definitions of Terms.............................................................................. v 
Abstract ................................................................................................................................. vi 
Protocol Synopsis ................................................................................................................. vii 
Figure 1: Study Diagram ....................................................................................................... x 
1 
BACKGROUND INFORMATION AND RATIONALE ....................................................................... 1 
1.1 
INTRODUCTION ..................................................................................................................................... 1 
1.2 
NAME AND DESCRIPTION INTERVENTION ............................................................................................. 1 
1.3 
RELEVANT LITERATURE AND DATA ..................................................................................................... 1 
1.4 
COMPLIANCE STATEMENT .................................................................................................................... 3 
2 
STUDY OBJECTIVES .............................................................................................................................. 4 
2.1 
PRIMARY OBJECTIVE ............................................................................................................................ 4 
2.2 
SECONDARY OBJECTIVES ..................................................................................................................... 4 
3 
INVESTIGATIONAL PLAN .................................................................................................................... 4 
3.1 
GENERAL SCHEMA OF STUDY DESIGN ................................................................................................. 4 
3.1.1 
Screening Phase .............................................................................................................................. 4 
3.1.2 
Study Intervention Phase ................................................................................................................. 4 
CHART REVIEW TO COLLECT INFORMATION REGARDING ANY INTUBATION RELATED AES. ............................... 5 
3.2 
ALLOCATION TO TREATMENT GROUPS AND BLINDING ........................................................................ 5 
3.3 
STUDY DURATION, ENROLLMENT AND NUMBER OF SITES ................................................................... 5 
3.3.1 
Duration of Study Participation ...................................................................................................... 5 
3.3.2 
Total Number of Study Sites/Total Number of Subjects Projected .................................................. 5 
3.4 
STUDY POPULATION ............................................................................................................................. 5 
3.4.1 
Inclusion Criteria ............................................................................................................................ 5 
3.4.2 
Exclusion Criteria ........................................................................................................................... 6 
4 
STUDY PROCEDURES ............................................................................................................................ 6 
4.1 
SCREENING VISIT ................................................................................................................................. 6 
4.2 
STUDY PROCEDURE .............................................................................................................................. 6 
4.2.1 
Clinician qualification: ................................................................................................................... 6 
4.2.2 
Randomization: ............................................................................................................................... 7 
4.2.3 
Intubation: ....................................................................................................................................... 7 
4.2.4 
Follow-Up (Post intubation chart review) ...................................................................................... 7 
4.3 
SUBJECT COMPLETION/WITHDRAWAL ................................................................................................. 8 
4.3.1 
Early Termination Study Visit ......................................................................................................... 8 
5 
STUDY EVALUATIONS AND MEASUREMENTS .............................................................................. 8 
5.1 
SCREENING AND MONITORING EVALUATIONS AND MEASUREMENTS .................................................. 8 
5.1.1 
Medical Records Review ................................................................................................................. 8 
5.1.2 
Clinician’s Records ......................................................................................................................... 9 
5.1.3 
Intubation ........................................................................................................................................ 9 
5.2 
SAFETY EVALUATION ........................................................................................................................... 9 
6 
INVESTIGATOR STATISTICAL CONSIDERATIONS ...................................................................... 9 
6.1 
PRIMARY ENDPOINT ............................................................................................................................. 9 
6.2 
SECONDARY ENDPOINT ........................................................................................................................ 9 
6.3 
STATISTICAL METHODS...................................................................................................................... 10 
6.3.1 
Baseline Data ................................................................................................................................ 10 
6.3.2 
Statistical Analysis ........................................................................................................................ 10 

 
 
 
 
 
 
 
 
 
 
iv
6.3.3 
Efficacy Analysis ........................................................................................................................... 11 
6.4 
SAMPLE SIZE AND POWER .................................................................................................................. 11 
6.5 
INTERIM ANALYSIS ............................................................................................................................ 12 
7 
STUDY DEVICE ...................................................................................................................................... 12 
7.1 
DESCRIPTION ...................................................................................................................................... 12 
8 
SAFETY MANAGEMENT ..................................................................................................................... 12 
8.1 
CLINICAL ADVERSE EVENTS .............................................................................................................. 12 
8.2 
ADVERSE EVENT REPORTING ............................................................................................................. 13 
8.3 
DEFINITION OF AN ADVERSE EVENT .................................................................................................. 13 
9 
STUDY ADMINISTRATION ................................................................................................................. 13 
9.1 
TREATMENT ASSIGNMENT METHODS................................................................................................. 13 
9.1.1 
Randomization............................................................................................................................... 13 
9.1.2 
Blinding ......................................................................................................................................... 13 
9.2 
DATA COLLECTION AND MANAGEMENT ............................................................................................ 13 
9.3 
DATA TRANSFER ................................................................................................................................ 14 
9.4 
RETENTION ......................................................................................................................................... 14 
9.5 
CONFIDENTIALITY .............................................................................................................................. 14 
10 
REGULATORY AND ETHICAL CONSIDERATIONS ..................................................................... 15 
10.1 
DATA AND SAFETY MONITORING PLAN ............................................................................................. 15 
10.1.1 
Risk Assessment ........................................................................................................................ 15 
10.1.2 
Potential Benefits of Trial Participation ................................................................................... 15 
10.2 
RECRUITMENT STRATEGY .................................................................................................................. 15 
10.3 
INFORMED CONSENT/ASSENT AND HIPAA AUTHORIZATION ............................................................ 16 
10.4 
PAYMENT TO SUBJECTS/FAMILY ........................................................................................................ 16 
NONE ............................................................................................................................................................... 16 
11 
PUBLICATION ........................................................................................................................................ 16 
12 
REFERENCES ......................................................................................................................................... 16 
 

 
 
 
 
 
 
 
 
 
 
v
ABBREVIATIONS AND DEFINITIONS OF TERMS 
AE 
 
Adverse event 
APSF 
 
Anesthesia Patient Safety Foundation 
ASA 
 
American Society of Anesthesiologists 
CFR 
 
Code of Federal Regulations 
CHOP 
 
The Children’s Hospital of Philadelphia 
CRNA 
 
Certified Nurse Anesthetist 
DL 
 
Standard Direct Laryngoscopy 
DSMB 
 
Data Safety Monitoring Board 
DUA 
 
Data Use Agreement 
EDC 
 
Electronic Data Collection 
FDA 
 
Food and Drug Administration 
HIPAA 
 
Health Information Portability and Accountability Act 
ICF 
 
Informed consent form 
MRN 
 
Medical records number 
OR 
 
Operating room 
PHI 
 
Protected health information 
REDCap 
 
Research Electronic Data Capture 
SAE 
 
Serious Adverse Events 
SAE 
 
Serious adverse event 
TI 
 
Tracheal Intubation 
VL 
 
Video Laryngoscopy 
EDC 
 
Electronic Data Capture  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 
 
vi
ABSTRACT 
Context:   
Complications related to infant (< 1 year) airway management are under-appreciated 
because of few rigorous and targeted studies. We have recently shown that multiple tracheal 
intubation (TI) attempts are a key risk factor for intubation-related complications in small 
children1. Tracheal Intubation using Video laryngoscopy (VL) has become popular in 
anesthesiology practice because of several advantages over conventional direct 
laryngoscopy (DL). Studies show that VL improves the view of the airway compared to DL, 
requires fewer intubation attempts, but may take more time to intubate the trachea. Our 
multicenter quality improvement project of children with difficult intubations demonstrated 
that using VL instead of DL was associated with fewer TI attempts and fewer complications.  
 
Objectives:  
• Primary Objective 
To compare the tracheal intubation (TI) first attempt success rate using VL vs. DL in 
children < 12 months old. 
• Secondary Objectives 
 Number of attempts for successful intubation 
 Frequency of failure to intubate with assigned device 
 Frequency of complications such as hypoxemia related to intubation with the two 
study devices 
 
Study Design:  
Prospective, randomized, multi-center parallel group trial 
 
Setting/Participants: 
This will be a multi-center study with a minimum of four participating centers. The target 
population will be children < 12 months age scheduled for elective surgery requiring general 
anesthesia with endotracheal intubation. 
 
Study Interventions and Measures:  
The study intervention will be a 1:1 randomization to perform tracheal intubation with the 
Storz C-Mac Video Videolaryngoscopy (VL) or the Standard Direct Laryngoscope (DL). 
 
Main study outcome measures are as follows: 
o The first intubation attempt success rate with each device 
o The number of attempts for successful intubation with each device 
o Complications associated with intubation 
 

 
 
 
 
 
 
 
 
 
 
vii 
PROTOCOL SYNOPSIS 
 
Study Title 
The Videolaryngoscopy in Small Infants (VISI) Trial 
Funder 
Anesthesia Patient Safety Foundation (APSF)   
Study Rationale 
Tracheal Intubation in normal infants maybe associated with 
complications related to multiple failed attempts. Using VL is 
associated with fewer failed attempts and complications in patients 
with difficult airways. No studies have compared the performance 
of VL to DL in small children with normal airways in the operating 
room. 
Study Objective(s) 
Primary  
To compare the tracheal intubation (TI) first attempt success rate in 
children < 12 months as compared to DL vs DL 
Secondary 
• Number of attempts for successful intubation 
• Frequency of failure to intubate with assigned device 
• Frequency of complications such as hypoxemia related to 
intubation with the two study devices 
Test Article(s) 
Storz C-MAC Video Laryngoscope and Standard Direct 
Laryngoscope 
Study Design 
Prospective, randomized, multi-center controlled trial 
Subject Population 
key criteria for 
Inclusion and 
Exclusion: 
Inclusion Criteria 
1) Males or females age 0 to <12 months.   
2) Scheduled for non-cardiac surgery or procedure lasting longer 
than 30 minutes under general anesthesia where oral 
endotracheal intubation will be performed. 
3) For clinician participants: anesthesia attending, or anesthesia 
fellow, or anesthesia resident who is willing provide baseline 
clinical experience information 
 
For clinician participants:  
1) Anesthesia attending, anesthesia fellows, or anesthesia resident 
 
Exclusion Criteria 
1) History of difficult intubation 
2) History with abnormal airway  
3) Predictive of difficult intubation upon physical examination  

 
 
 
 
 
 
 
 
 
 
viii
4) Parents/guardians who, in the opinion of the investigator, may 
be unable to understand or give informed consent 
 
Number Of Subjects  
 
It is expected that approximately 650 subjects will be enrolled to 
produce 550 evaluable subjects. Single site enrollment will be 
capped at 250 subjects or 200 evaluable subjects.  
 
It’s expected approximately 500 anesthesia clinician participants 
will be enrolled. There is no maximal allowed participating 
clinicians at each site.    
Study Duration 
Each subject’s participation will last up to 24 hours post intubation. 
We expect to complete the enrollment in about two years. 
Study Phases 
Screening 
Study Treatment 
Follow-Up   
 (1) Screening: identifying potential subjects  and obtaining consent 
 (2) Intervention: randomization  
 (3) Follow-up: Chart review for intubation related adverse events 
up to 24 hrs Post-intubation  
 
For clinician participants 
(1) Screening: identifying anesthesia clinicians from the department 
list 
(2) Consent: verbal consent will be obtained 
(3) Clinical experience data will be collected  
(4)  
Efficacy Evaluations 
The primary efficacy endpoint will be successful tracheal intubation  
Safety Evaluations 
Tracheal intubation by VL or DL are routine standard of care at 
each participating center. Other than randomization, there is no 
study intervention that will be introduced to the subjects. Subjects 
will be monitored per institutional standard practice. Any procedure 
related AEs will be treated per institutional standard practice. 
Statistical And 
Analytic Plan 
We will consider a 10% improvement in first attempt success rate 
for VL compared to DL to be indicative of a significant clinical 
effect. The statistical analysis of this change will be based on a 
logistic regression model where an odds ratio greater than 2.98 will 
be considered evidence of efficacy of VL compared to DL. The 
GEE method will be applied to adjust for clinician-level correlation 
of the outcome variable. There will be an interim analysis when 224 
evaluable subjects are enrolled. The proportion of subjects that are 
successfully intubated at the first attempt will be compared for VL 
and DL using conditional logistic regression with alpha = 0.029 

 
 
 
 
 
 
 
 
 
 
ix
used for significance.  This more stringent criteria for significance 
(0.029 instead of 0.05) is Pocock’s method of correction for 
maintaining overall study significance level at 0.05 when there is 
one interim analysis the overall estimate. 
DATA AND SAFETY 
MONITORING PLAN 
Each participating site PI will be responsible for oversight of the 
study safety. We expect no more than standard clinical risks 
associated with intubation. There is no DSMB for this study. 
 
 
 

 
 
 
 
 
 
 
 
 
 
x
FIGURE 1: STUDY DIAGRAM 
 
Screening 
Screening 
Failures 
Randomize  
(Stratified by 
site & 
clinician’s role) 
24h Follow Up 
Chart Review: Complications 
Abandon or Cross over  
Non-Evaluable:  
Abnormal airway 
upon PE 
If 1st attempt fails 
@attending discretion 
DL 
VL 

 
  
 
 
 
1
1 
BACKGROUND INFORMATION AND RATIONALE 
1.1 Introduction 
Our preliminary work and others have shown that complications in airway management are 
related to the persistent use of direct laryngoscopy and multiple tracheal intubation attempts. 
Our previous multicenter study showed that 20% of children experienced a complication and 
children who weighed less than 10kg had 2x the complication rate OR(95% CI) 2.09(1.51-
2.88) p < 0.0001. In both our difficult airway and normal airway populations more than 2 
attempts increased the complication rate 1.5x and 1.4x respectively. This proposal seeks to 
reduce complications by reducing the number of attempts. Multiple tracheal intubation 
attempts often occur because, in many teaching centers, trainees make the first attempt and 
after a variable number of failures, the supervising anesthesiologist steps in to repeat the 
technique. The supervising anesthesiologist often repeats direct laryngoscopy because they 
are unable to assess the view obtained by the trainee using standard direct laryngoscopy. Our 
finding of increased complications has transformed our thinking about repeated intubation 
attempts. Each attempt is a potentially high-risk event and represents an opportunity for 
hypoxemia, esophageal intubation, laryngospasm, bronchospasm, cardiac arrest, airway 
trauma and other adverse outcomes. It has become evident to us that multiple tracheal 
intubation attempts are a key modifiable risk factor to reduce tracheal intubation associated 
complications in children. Videolaryngoscopy allows the supervising clinician to share the 
view of the trainee and guide them more effectively. Experienced laryngoscopists also 
benefit from videolaryngoscopy because they obtain a magnified and improved view. 
Videolaryngoscopy may narrow the success rate gap between trainees and experienced 
laryngoscopists. We hypothesize that VL as the first attempted device will reduce the 
number of tracheal intubation attempts and tracheal intubation related complications, 
specifically intubation associated hypoxemia.  
 
1.2 Name and Description Intervention 
Tracheal intubation per clinical standard practice by using the randomized intubation device 
which are both institution approved devices used routinely.  
 
1.3 Relevant Literature and Data 
Sun and colleagues performed a meta-analysis of randomized controlled trials comparing 
VL and DL in children and concluded that VL improved laryngeal visualization, but that this 
came at the expense of prolonged intubation time and increased intubation failures 1.  The 
investigators found no significant difference between first attempt success rates of DL and 
VL2. This meta-analysis had significant weaknesses because of marked heterogeneity in 
patient characteristics; the clinician’s experience, the type of VLs used and varied 
definitions of outcomes.  The authors included fourteen trials in this meta-analysis, but only 
two studies specified the same age range of patients.  Age is an important factor when 

 
  
 
 
 
2
determining the clinical efficacy of laryngoscopes since the pediatric airway is in transition 
from birth until about age 2. 
Lingappan and colleagues attempted to compare DLs and VLs in neonates, but were unable 
to do so due to the lack of randomized controlled trials that specifically compared VL to DL 
in neonates3.   
Multiple attempts at tracheal intubation have been associated with severe complications in 
diverse clinical settings4-7.   
• Souza et al. found in a study of 147 children in the ICU that 14.3% required 5 or 
more attempts and that attempts were associated with more trauma, hypoxemia and 
bradycardia8.   
• Another study examined the impact of introducing non-angulated video 
laryngoscopy on advanced airway management success by critical care transport 
paramedics and nurses in the prehospital setting. After the introduction of 
videolaryngoscopy, first pass success rates increased from 75.4% to 94.9% 
(significant at CI 99%, chi square = 35.12, Fisher’s exact test), combined first and 
second pass success rates increased from 89.2% to 97.4% (significant at CI 99%, chi 
square = 12.44, Fisher’s exact test).  
• We conducted a prospective multicenter study (PeDI Registry) examining our 
tracheal intubation practice in children with difficult airways and found that 
hypoxemia was common and hypoxemic cardiac arrest occurred in 1:80 patients. We 
associated multiple attempts >2 with more complications and every attempt was 
associated with more complications odds ratio 1.5 per attempt (95% CI 1.4-1.6; 
p<0.0001). In a large comparative retrospective analysis of VL to DL using the 
National Emergency Airway Registry for Children’s ICU database, our team found 
that using videolaryngoscopy was independently associated with a lower occurrence 
of tracheal intubation adverse events (adjusted odds ratio, 0.57; 95% CI, 0.42-0.77; 
p< 0.001) but not severe tracheal intubation adverse events (adjusted odds ratio, 0.86 
CI, 0.56-1.32; p =0.49) or fewer multiple attempts at tracheal intubation (adjusted 
odds ratio, 0.93; 95% CI, 0.71-1.22; p= 0.59). Videolaryngoscopy was associated 
with lower odds of bronchial intubation (OR, 0.40; 95% CI, 0.22-0.74; p= 0.003), 
esophageal intubation with immediate recognition (OR, 0.49; 95% CI, 0.34-0.69; p < 
0.001) and dysrhythmia (OR, 0.49; 95% CI, 0.15-0.88; p = 0.019)9. Although in this 
study videolaryngoscopy did not reduce multiple attempts, we believe this result is 
not applicable to our proposed study for a few reasons. Firstly, there was 
heterogeneity in the type of videolaryngoscopy being used i.e. non-angulated and 
angulated videolaryngoscopy were used and the type was not noted on all the data 
collection forms. Angulated videolaryngoscopes have been shown to prolong 
intubation time and are associated with more difficulty with inserting the breathing 
tube. Secondly, the population studied was primarily older children in ICU’s, and 

 
  
 
 
 
3
finally, there was a selection bias in the study, with videolaryngoscopy being 
disproportionately chosen for children with difficult airways.  
• A recent Cochrane review of videolaryngoscopy vs direct laryngoscopy for tracheal 
intubation in children (excluding neonates) further highlights the urgent need for 
high quality prospective randomized studies. In that review the authors had difficulty 
reaching conclusions because of “very low quality evidence due to imprecision, 
inconsistency and study limitations”10.  
• We performed a retrospective cohort analysis (data pending publication) using our 
electronic medical records to rigorously analyze our experience with infants with 
normal airways presenting for elective surgery between January 24, 2015 and August 
1, 2016. Of the 7125 cases performed on children younger than 12 months old, we 
included those managed with direct laryngoscopy without comorbidities presenting 
for elective surgery. We analyzed the final dataset of 1343 cases and found that 
15.6% of cases required more than 1 attempt. We used our electronic medical record 
data logs to determine episodes of severe hypoxemia (sp02 <90% for more than 1 
minute) occurring around the time of intubation (from anesthesia start to anesthesia 
ready). We found that the number of laryngoscopy attempts was significantly 
associated with hypoxemic events (Univariate - Poisson: RR 1.4257 (95% CI 1.2576 
- 1.6164) p <.0001 , Negative Binomial: RR 1.4421 (95% CI 1.2289 - 1.6922) p 
<.0001, GEE:  RR 1.4421 (95% CI 1.2596 - 1.6510)) p <.0001), (Multivariate - 
Poisson: RR 1.3256 (95% CI 1.1363 - 1.5463) p= 0.0003, Negative Binomial: RR 
1.3707 (95% CI 1.1327 - 1.6585) p= 0.0012 ,  GEE: RR 1.3707 (95% CI 1.1302 - 
1.6623) p=0.0014)). Our analysis showed that the (371 of 1134) 32.7% of children 
with one attempt experienced severe hypoxemia while (101 of 210) 48.1% of those 
with multiple attempts experienced severe hypoxemia. These results are likely an 
over estimation of the true incidence of severe hypoxemia since there was no way for 
us to exclude low oxygen saturation readings related to tourniquets applied during 
intravenous access. Nevertheless, the differences between the two conditions 
(multiple vs. single attempt) are likely accurate since it is unlikely there was a 
disproportionate application of tourniquets in one group versus the other.  
 
Taken together these preliminary data and prior studies demonstrate the significance of 
the problem and the feasibility and validity of our intervention to reduce complications.  
A prospective randomized trial is the only way to eliminate these issues. 
 
1.4 Compliance Statement 
This study will be conducted in full accordance all applicable Federal and state laws and 
regulations including 45 CFR 46, and the HIPAA Privacy Rule. Any episode of 
noncompliance will be documented and reported. 
 

 
  
 
 
 
4
The investigators will perform the study in accordance with this protocol, will comply with 
applicable institutional research policies, and will report unexpected problems in accordance 
with institutional IRB Policies and Procedures and all federal requirements. Collection, 
recording, and reporting of data will be accurate and will ensure the privacy, health, and 
welfare of research subjects during and after the study. 
 
2 
STUDY OBJECTIVES 
2.1 Primary Objective 
The primary objective is to determine if VL increases the first TI success rate in children < 
12 months as compared to DL  
 
2.2 Secondary Objectives 
• Number of attempts for successful intubation 
• Frequency of failure to intubate with assigned device 
• Frequency of complications such as hypoxemia related to intubation with the two 
study devices 
 
3 
INVESTIGATIONAL PLAN 
3.1 General Schema of Study Design 
This study is a prospective, randomized, multi-centered controlled trial.  
 
3.1.1 Screening Phase 
Potential subjects will be identified from patients scheduled for elective surgery or 
procedure per protocol inclusion and exclusion criteria. Parental/guardian permission 
(informed consent) will be obtained prior to any study related procedures being performed. 
 
Potential clinician participants will be identified from departmental anesthesia clinician lists 
including attending anesthesiologists, anesthesia fellows, and anesthesia residents.  
 
3.1.2 Study Intervention Phase 
3.1.2.1 Randomization: 
The only research procedure is randomization to TI device as VL or DL for the first 
intubation attempt.  
 
3.1.2.2 Intubation:  
Tracheal intubation using VL or DL are clinical standards of care devices at all participating 
centers.   
  

 
  
 
 
 
5
3.1.2.3 Follow-up (Up to 24 hours after intubation) 
Chart review to collect information regarding any intubation related AEs. 
 
3.2 Allocation to Treatment Groups and Blinding 
CHOP will be the Data Coordinate Center (DCC). The DCC will generate the randomization 
sequence by statisticians. The randomization sequence will be maintained in study EDC, a 
CHOP REDCap registry, by study manager at DCC. 
 
Randomization will be stratified by site and clinician’s role at each site with random block 
sizes of 2, 4 or 6 to ensure equal numbers of VL and DL subjects within each site and type 
of clinician, and, to avoid predictability of the device.  Randomization is only for the first 
intubation attempt. Any subsequent attempts will be at the supervising clinician’s discretion 
either with the randomized device or an alternate device 
 
Blinding of study device and study staff is not feasible in this study. However, the 
statisticians will be blinded at the time of data analysis. 
 
3.3 Study Duration, Enrollment and Number of Sites 
3.3.1 Duration of Study Participation 
The study duration per subject will be up to 24 hour post-intubation.  
The study duration for clinician participants could be up to the study enrollment duration. 
 
3.3.2 Total Number of Study Sites/Total Number of Subjects Projected 
The study will be conducted at 4-10 centers in the United States, United Kingdom and 
Australia. It is expected that approximately 650 subjects will be enrolled to produce 550 
evaluable subjects. Single site enrollment will be capped at 250 subjects or 200 evaluable 
subjects.   
 
It’s expected approximately 500 qualified anesthesia clinician participants will be enrolled. 
The number of qualified anesthesia clinicians varies across the sites. We estimate about 20-
200 per site. There is no maximal allowed participating anesthesia clinicians at each site.  
 
3.4 Study Population 
 
3.4.1 Inclusion Criteria 
1) Males or females age 0 to <12 months.   
2) Scheduled for non-cardiac surgery or procedure lasting longer than 30 minutes under 
general anesthesia where oral endotracheal intubation will be performed by an 
anesthesiology clinician. 
3) Parental/guardian permission (informed consent). 

 
  
 
 
 
6
 
For clinician participants:  
1) Anesthesia attending, anesthesia fellows, or anesthesia resident 
 
 
3.4.2 Exclusion Criteria 
1) History of difficult intubation 
2) History with abnormal airway 
3) Predictive of difficult intubation upon physical examination  
4) Parents/guardians who, in the opinion of the investigator, may be unable to understand 
or give informed consent 
 
Subjects that do not meet all of the enrollment criteria may not be enrolled. Any violations 
of these criteria must be reported in accordance with IRB Policies and Procedures. 
 
4 
STUDY PROCEDURES 
4.1 Screening Visit 
Eligible subject’s parent(s) or guardian(s) will be approached by investigator and/or 
study staff prior to surgery. Parent(s) or guardian(s) will be provided a written 
informed consent before any study specific procedures are performed. Following 
activities will be conducted at this visit: 
• Medical Record Review 
• Informed Consent 
• Data collection 
 
4.2 Study Procedure  
4.2.1 Clinician qualification: 
Since the study procedure is standard clinical care at all centers, anyone who is 
licensed to perform the tracheal intubation at the participating center is allowed to 
conduct the intubation on the subjects. These clinicians include attending 
anesthesiologists, anesthesia fellows, or anesthesia residents.    
 
All clinicians who are caring for a VISI trial patient will be consented. In clinical 
emergency situations, the attending anesthesiologist may request subsequent 
intubation attempts assistance from another attending anesthesiologists who may not 
be consented. This will not be considered as protocol violation nor deviation. We 
will request consent from these clinicians after the intubation. If they decline 
consent, none of their study information will be collected. No study procedure will 
be performed till consent is obtained.    
 

 
  
 
 
 
7
4.2.2 Randomization:  
To ensure balance in treatment assignment, a permuted-block randomization 
approach will be applied. The block size will be varying (among 2, 4, 6) to avoid the 
predictability of device assignment. To further balance device assignment against 
potential predictors on the outcome, we’ll stratify the randomization by study site (5-
10 sites) and clinician’s experience (anesthesia attending, anesthesia fellow & 
anesthesia resident). There will be 15-30 (Site number*3) strata in total. Separate 
randomization schedule will be generated for each stratum. 
 
Randomization will be conducted through the study REDCap EDC after the consent 
is obtained. The subject is required to be registered in REDCap via a computer or 
mobile device per institutional policy prior to randomization. To avoid protocol 
deviation, only eligible subjects and study allowed anesthesia clinicians are able to 
be randomized in REDCap by a designated site study staff. Then the clinician will be 
notified of the randomized device.  
 
4.2.3 Intubation: 
Anesthesia induction will be left to the discretion of the attending anesthesiologist 
per institution standard practice. However, it’s strongly recommended that all 
subjects should receive a neuromuscular blocking drug and confirmed train of four ≤ 
1 twitch at the adductor pollicis muscle prior to attempting intubation. It’s strongly 
recommended that the use of a malleable stylet for all intubations and use usual 
cuffed tracheal tubes per institutional standard of care. It’s strongly recommend to 
follow below guidelines:  
• ID 3.0mm cuffed (birth to < 1 month; >3kg body weight);  
• ID 3.5mm cuffed (1 month to < 8 months);  
• ID 4.0mm cuffed (8 to 12 months).   
 
If the first attempt at tracheal intubation attempt fails, the device used for subsequent 
attempts will be at the discretion of the attending anesthesiologist.  
 
A member of the research staff is required to observe the intubation and record the 
study information. 
 
4.2.4 Follow-Up (Post intubation chart review)  
Subject records will be reviewed up to 24 hours after intubation or upon discharge 
from PACU for intubation related AEs  
 
The following data elements will be collected:  

 
  
 
 
 
8
• Demographics including MRN, name, gender, weight, and elements of dates 
including date of birth et al 
• Birth history including post menstrual age et al 
• Medical history and surgical history including diagnosis and any other intubation 
history et al 
• Physical exam including ASA physical status and airway abnormality et al 
• Surgical information including procedure date, type of surgical procedure, surgery 
length et al.  
• Anesthesia records including number of TI attempts, oxygen saturation, TI device 
used, clinician’s names, medications, and associated complications et al 
• Subject records will be reviewed up to 24 hours after intubation for any intubation 
related AEs 
 
4.3 Subject Completion/Withdrawal 
The subject may be discontinued from the study procedure at the discretion of the 
Investigator due to AEs or to protect the subject for reasons of safety or for administrative 
reasons.  It will be documented whether or not each subject completes the clinical study. If 
the Investigator becomes aware of any serious, related adverse events after the subject 
completes or withdraws from the study, they will be recorded and reported to institutional 
IRB. 
 
Clinician participates maybe withdraw from participating in the study at the first intubation 
attempt. If this occurs, their names will removed from the eligible clinicians list in REDCap.  
 
4.3.1 Early Termination Study Visit 
If a subject withdraws from the study, then their data which has already been collected will 
remain in the study. If they withdraw after being intubated, the 24 hour post intubation 
review of records will be done to assure no AE has occurred as a result of the intubation for 
safety monitoring.  However, if subject withdraws prior to being intubated, no further data 
will be collected and no study procedure will be performed.  
 
5 
STUDY EVALUATIONS AND MEASUREMENTS 
5.1 Screening and Monitoring Evaluations and Measurements 
5.1.1 Medical Records Review 
• Demographics including MRN, name, and elements of dates including date of birth 
at el 
• Birth history including post menstrual age and congenital birth defect et al 
• Medical history and surgical history including diagnosis and any previous intubation 
history et al 

 
  
 
 
 
9
• Chart review to collect clinical information up to 24-hour post intubation or upon 
discharge from PACU 
• ASA physical status  
• Airway assessment 
• Surgical information including procedure date, type of surgical procedure, surgery 
length et al.  
• Anesthesia records including vital signs, oxygen saturation, medications, and notes  
• Post intubation assessment including complications associated with intubation 
5.1.2 Clinician’s Records 
• Clinician’s clinical role and years of professional experiences 
• Experiences of study device intubation on infant  
5.1.3 Intubation 
• Clinicians’ name who perform the intubation 
• Number of attempts 
• Intubation devices 
• Intubation associated complications  
 
5.2 Safety Evaluation 
Subject safety will be monitored and treated by per institutional standard clinical of care 
since the study procedure is institutional standard practice. Any adverse event related to 
intubation will be recorded on the study Case Report Form (CRF).  
 
6 
INVESTIGATOR STATISTICAL CONSIDERATIONS 
6.1 Primary Endpoint 
The primary aim is to determine the proportion of tracheal intubation success on first 
attempt of VL compared to DL. The primary endpoint is the successful tracheal intubation at 
first attempt. The first-attempt success of intubation will be coded as a dichotomous variable 
(success=1, nonsuccess=0). As a comparative effectiveness study, the treatment procedure 
will be randomly assigned to participants after consent is obtained in a two-arm, parallel 
design. If warranted, we will use a logistic regression model in the mixed model framework 
to allow for the inclusion of multi-level effects for individuals nested within sites and site-
specific effects such as staffing, caseload, experience of staff, etc. In this analysis, we can 
address systematic effects that possibly lead to different success rates between sites, and/or 
clinicians, without compromising the integrity of the randomization procedure. Although the 
main interest is in successful intubation, secondary aims can also be investigated through the 
logistic regression mixed models approach. 
 
6.2 Secondary Endpoint 
The secondary endpoint is successful tracheal intubation.  

 
  
 
 
 
10 
 
6.3 Statistical Methods 
6.3.1 Baseline Data  
Baseline and demographic characteristics will be summarized by standard descriptive 
summaries (e.g. means and standard deviations for continuous variables such as age and 
percentages for categorical variables such as gender). To test the difference of demographic 
variables between treatment groups, student’s t-test or Wilcoxon test will be used for 
continuous variables, while Chi-square test, or Fisher’s exact test will be used for categorical 
variables. Comparisons of demographic characteristics between the sites will be 
accomplished by reporting effect size measurements (i.e., Cohen’s d, phi-coefficient, odds 
ratios) between each site as a descriptive analysis of differences at baseline. 
 
6.3.2 Statistical Analysis 
The study is powered for the primary outcome: successful tracheal intubation on first 
attempt.  Assuming that a 10% increase in successful tracheal intubation (i.e., intubation on 
first attempt) is clinically meaningful, and that a reasonable rate for baseline success is 
(84%) (Based on our single center data) an overall sample size of 540 randomly assigned to 
VL or DL, will provide approximately 80 % power at the nominal two sided 5% level of 
significance.  This calculation accounts for approximately 10% withdrawal, dropout, 
missing data and other data quality issues. We assume the success rate will be similar across 
sites.  The statistical package SAS’s module: PROC SEQDESIGN, was used for the sample 
size determination.  The order of assignment of intubation method (VL vs. DL) for patients 
intubated by the same clinician will be done using blocked randomization with block sizes 
of 2, 4 or 6.  The primary analysis will be based on intention-to-treat approach and include 
all the randomized subjects. Logistic regression will be used to compare first-attempt 
success proportion of tracheal intubation between DL and VL. To adjust for clinician-level 
clustering of outcome variable, we will apply generalized estimating equations (GEE) 
method to the logistic regression model to get the marginal odds ratio for first-attempt 
success comparing VL and DL. . We will include the patient characteristics: ASA status, 
thyromental distance and weight (less than 10kg, & more than 10kg) as covariates in the 
logistic regression model. Since there will be an interim analysis the p-value is considered 
significant if it is less than 0.029 to maintain the overall significance level of the study (Type 
I error rate) at 0.0514  Also, it may be that VL offers greater advantage for those with less 
experience such as residents as compared to attending physicians or fellows.  To assess if 
there is this effect modification we will include class of clinicians with intervention (DL vs 
VL) as an interaction term in the logistic regression. In addition, we will analyze the number 
(not dichotomizing) of intubation attempts using a generalized linear model with the 
negative binomial distribution. Difference in complications, such as lowest oxygen 
saturation during tracheal, between treatment groups will be analyzed in multivariate linear 
models or generalized linear models as appropriate. General linear models and GEE 

 
  
 
 
 
11 
approach will be used for these models to adjust for site-level and clinician-level clustering 
of outcome variables. 
 
6.3.3 Efficacy Analysis 
The primary analysis will be based on an intention to treat approach and will include all 
randomized subjects.   
 
The primary efficacy endpoint will be a successful tracheal intubation following the 
procedure. We will consider a 10% improvement between VL compared to DL to be 
indicative of a significant clinical effect. The statistical analysis of this change will be based 
on a logistic regression model where an odds ratio greater than 2.98 will be considered 
evidence of efficacy of VL compared to DL. Marginal odds ratios with 95% confidence 
intervals will be reported for the sample overall, as well as each site, if appropriate. 
 
6.4 Sample Size and Power 
The primary objective of the trial is to determine whether VL will increase the success rate 
on first tracheal intubation in children < 12 months as compared to DL. The null hypothesis 
is that first-attempt success rate will not be different between VL and DL for children < 12 
month. The alternative hypothesis is that the first-attempt success rate will be different 
between VL and DL for children < 12 month. The mathematical formula are: 
H0: pVL = pDL 
H1: pVL≠ pDL 
An interim analysis will be done, and Pocock’s method will be used to adjust for this 2-stage 
sequential analysis. According to CHOP’s recordings, first tracheal intubation success 
proportion was 84% for DL, and we expect a difference in the success proportion of 10% to 
be clinically meaningful. Using SAS PROC SEQDESIGN procedure, a sample size of 167 
per treatment group (334 in total) will provide approximately 80% power at the nominal two 
sided 5% level of significance. To adjust for 10% extra protocol deviation, the sample size 
adds up to 186 per treatment group (372 in total). 
 
We’re also aware that the outcome variable will be clustering on each physician since 
different physician perform differently in tracheal intubation. The following inflation factor 
formula will be used to adjust for this clustering: 
DE=1+(m-1)*𝜌𝜌 13  
Where DE stands for design effect, m stands for the average clustering size, and 𝜌𝜌 stands for 
intra-cluster correlation coefficient (ICC). Since there is no reported ICC of the tracheal 
intubation success rate among clinicians, we assume it to be 0.05, which means 5% of the 
variance in success rate is explained by the variation between clinicians. We also assume 
that every clinician will intubate 10 patients on average in the current study. Thus, the 

 
  
 
 
 
12 
inflation factor is 1.45. Thus, the sample size is inflated to 270 per treatment group (540 in 
total). 
 
6.5 Interim Analysis 
There will be an interim analysis after 224 evaluable subjects are enrolled. The proportion of 
subjects that are successfully intubated at the first attempt will be compared for VL and DL 
using logistic regression with alpha = 0.029 for significance.  This more stringent criteria for 
significance (0.029 instead of 0.05) is Pocock’s method of correction for maintaining overall 
study significance level at .05 when there is one interim analysis. We will include ASA 
status, thyromental distance and weight less than 10kg as covariates in the logistic 
regression. The probability of stopping at the interim analysis (mid-point) is 46.4%, if the 
true improvement in intubation first attempt success rate is 10.0% (i.e.  84% true first 
attempt success rate for DL vs. 94% true success rate for VL). However, if the true 
improvement in first attempt intubation success rate is 12.0% (i.e. 84% vs 96% for DL and 
VL respectively), then the probability of stopping early increases to 83.0%.  
 
7 
STUDY DEVICE  
7.1 Description 
Both Storz C-Mac Video Laryngoscope (VL) and Standard Direct Laryngoscope (DL) are 
FDA approved and used clinically for study population at all participating center.  
 
 
Standard Direct Laryngoscope      
 
Storz C-Mac blade 
 
The Storz C-Mac blade is a standard direct style blade with a CMOS camera embedded at 
the distal tip. The image from the camera is transmitted to a foldable display on the handle 
of the device. The imaging display is viewable by nearby other clinicians.  
The standard direct blade is a rigid style, visualization occurs by direct line of sight. 
 
8 
SAFETY MANAGEMENT 
8.1 Clinical Adverse Events 
Clinical adverse events (AEs) related to intubation will be monitored throughout the study.  
 

 
  
 
 
 
13 
8.2 Adverse Event Reporting 
Unanticipated problems related to the research involving risks to subjects or others that 
occur during the course of this study (including SAEs) will be reported to the IRB in 
accordance with institutional IRB SOP. AEs that are not serious but that are notable and 
could involve risks to subjects will be summarized in narrative or other format and 
submitted to the IRB at the time of continuing review.  
8.3 Definition of an Adverse Event 
An adverse event is any untoward medical occurrence in a subject who has received an 
intervention (drug, biologic, or other intervention).  The occurrence does not necessarily 
have to have a causal relationship with the treatment.  An AE can therefore be any 
unfavorable or unintended sign (including an abnormal laboratory finding, for example), 
symptom, or disease temporally associated with the use of a medicinal product, whether or 
not considered related to the medicinal product. 
 
All AEs related to the study intervention/intubation will be noted in the study records and on 
the case report form with a full description including the nature, date and time of onset, 
determination of non-serious versus serious, intensity (mild, moderate, severe), duration, 
causality, and outcome of the event. 
 
9 
STUDY ADMINISTRATION 
9.1 Treatment Assignment Methods 
9.1.1 Randomization 
The randomization schedule will be generated by statistician and randomized by using 
REDCap randomization feature. To avoid protocol violation, the randomization option in 
REDCap is only available to consented subjects when consented and anesthesia clinicians 
are scheduled to perform the intubation. Randomization schedule will be maintained by 
study manager at DCC in REDCap. The randomization will be stratified by site and 
clinicians role to ensure an equal number of study DL or VL participants at each center. 
REDCap will keep a permanent and unchangeable randomization records. 
 
9.1.2 Blinding 
Blinding of the PI and clinician is not feasible in this study. The statisticians will be blinded 
at the time of generating the randomization schedule and remain blinded at the time of 
analysis. 
 
9.2 Data Collection and Management 
DCC will be housed at CHOP. CHOP could also be IRB of record for other US based 
participating sites. CHOP REDCap will be utilized as Electronic Data Capture (EDC).    
 

 
  
 
 
 
14 
Minimal identifiable information might be printed on paper for study eligibility clarification, 
study data collection, and data validation. Any un-needed paper data which has identifiable 
information could be shredded as soon as possible per institutional policy.  
 
Study electronic records will be stored in institutional approved secured network drives or 
websites or databases, which are fully tracked with user credentials and only authorized 
research personnel have the access. Paper records will be secured in a locked office where 
only authorized research personnel have access. 
 
9.3 Data Transfer 
Study data including identifiers (MRN and names) and dates will be entered in the study 
EDC.  Scanned ICF could be uploaded to study EDC for monitoring. Full dataset could be 
exported from the EDC and saved in the DCC secured network for study monitoring and 
auditing, and data management. Only the site study staff and DCC would have access to site 
identifiers. Coded Limited dataset (including dates) could be shared with the statistician for 
data analysis and participating centers. 
 
9.4 Retention 
When the study is completed, all study paper records might be scanned and then destroyed 
to store along with other electronic study records for retention. These will be stored and 
backed up in an institutional approved secured network drive, website or database. Only 
authorized study personnel will have access. All study materials, including PHI and the 
master list, though not the information linking subject PHI with study data, will be retained 
for 10 years after the subjects turn 18 years old. Then the master link code will be permanent 
deleted.  
 
9.5 Confidentiality 
All data and records generated during this study will be kept confidential in accordance with 
each site’s Institutional policies and HIPAA on subject privacy. The Investigator and other 
site personnel will not use such data and records for any purpose other than conducting the 
study. Safeguards to maintain subject confidentiality are described under Data Collection 
and Management. 
 
No identifiable data will be used for future study without first obtaining IRB approval. The 
investigator will obtain a data use agreement between the provider (participating centers) of 
the data and the recipient researchers (CHOP) before sharing a limited dataset (PHI limited 
to dates).   
 
HIPAA does not apply to clinician participants. 
 

 
  
 
 
 
15 
10 REGULATORY AND ETHICAL CONSIDERATIONS 
10.1 Data and Safety Monitoring Plan 
The participating center’s principal investigator will oversee the safety of the data and that 
of the research subjects. During the study period, each subject will be monitored for any 
adverse events or safety concerns. Contacts will be provided to all enrolled subject’s 
parents/legal guardians with any concern. Study principal investigator will oversee overall 
safety of data. 
 
10.1.1 Risk Assessment 
Both devices are approved and used in accordance with their labeling, both approaches are 
currently used as part of routine clinical care at the institution; experienced clinicians will 
oversee the procedure and the protocol allows for cross-overs. The main risk of the study is 
due to randomization (to an intubation approach the subjects may not have undergone if 
their clinician had made the decision). Additionally VL may take longer however this has 
been shown to be clinically insignificant in all studies. The risks are no greater than 
minimal.  
 
10.1.2 Potential Benefits of Trial Participation 
This study might benefit some participants by faster intubation. They may have fewer 
intubation attempts thereby reducing intubation related risks.  
 
Risk-Benefit Assessment 
The risks of this study are no different than those associated with current practice for airway 
management in children undergoing general anesthesia for elective surgery. There are 
potential benefits to the greater population of children in that we will have knowledge about 
the efficacy of VL vs DL. 
 
10.2 Recruitment Strategy 
The PI at each participating center will provide an in-service to surgical and anesthesia team 
and related care providers. Potential subjects will be identified from the scheduled surgical 
list. A Study team member will review medical records to identify eligible subjects and will 
only approach permissible subjects. 
 
Subjects will be approached by a study team member in a private setting.  The study will be 
explained to the parent(s)/legal guardian(s) at an appropriate time when available to give 
consent. 
 
Clinician participants will be identified from the departmental clinician list. The site PI 
could initiate an email to all qualified clinicians. It will be reiterated that the confirmation 
that their decision to participate, or not, or their performance on the study will not impact 

 
  
 
 
 
16 
their performance evaluations or employment. They will have ample time to consider 
participating. 
 
10.3 Informed Consent/Assent and HIPAA Authorization 
Parent(s)/legal guardian(s) will be approached by study members prior to the surgery in a 
private setting. The primary aim, risks, benefits and study procedures for the study will be 
explained and the parent(s)/legal guardian(s) will have the ample time and opportunity to 
ask questions. Investigator will be available to answer any additional questions the 
parent(s)/legal guardian(s). It will be reiterated that the decision to participate or decline to 
participate in the study will have no bearing on their medical care.  
A combined consent-authorization document will be used. Only one signature from parent 
or legal guardian will be required for this study.  
 
For clinician participants, the primary aim and their obligations and requirements will be 
explained in the initial site PI’s email. Consent could be obtained via email, text message, 
phone calls, or in-person. For clinician who requested to assist subsequent intubation 
attempts on a VISI patient during the clinical emergency situation, study staff will approach 
to obtain the consent after the intubation has occurred. Consenting process will have to be 
documented electronically in study EDC and paper record will be optional or per 
institutional policy.  
 
10.4  Payment to Subjects/Family 
None 
 
11 PUBLICATION 
The results of this study will be published in a high impact journal, our target journal is the 
Lancet. 
 
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