Comparison of GlideScope® Titanium (Verathon) and Flexible Intubation Video Endoscope® (FIVE, Storz) In Terms Of Intubation Success In Infants With Pierre Robin Sequence
Phase: NA
Conditions: Intubation; Difficult or Failed
Sponsor: Hacettepe University

 
23.02.2021 
 
 
 
 
 
COMPARISON OF GLIDESCOPE® TITANIUM 
(VERATHON) AND FLEXIBLE INTUBATION VIDEO 
ENDOSCOPE® (FIVE, STORZ) IN TERMS OF 
INTUBATION SUCCESS IN INFANTS WITH PIERRE 
ROBIN SEQUENCE 
 
Begüm ERCAN 
Aysun ANKAY YILBAŞ 
Özge ÖZEN 
 
 
 
 
 
 
 
 
 
 

 
MATERIAL – METHOD 
Our study is a prospective randomized controlled trial. Intubation success and intubation times 
were compared with Flexible Intubation Video Endoscope (FIVE)® or GlideScope® Titanium 
devices in patients with Pierre Robin Sequence. Hacettepe University Clinical Research Ethics 
Committee (Date: 23.02.2021, Decision No: 2021/4-16 KA-20115) and Turkish Medicines and 
Medical Devices Agency (TITCK) approval letter was obtained (Number; E-688699933- 
511.06- 365554).  
Patients with Pierre Robin Sequence who were younger than 12 months and underwent elective 
surgery under general anesthesia between March 2021 and December 2023 were included in 
the study. Patients requiring emergency surgery, patients requiring rapid sequence intubation, 
patients who had already been intubated or tracheostomized to the operating room, patients who 
would not be operated on under general anesthesia, patients who did not have family consent 
and who could not provide informed consent were excluded from the study. Randomization 
was performed by a research assistant using a computer to generate random numbers 1 and 2 
and was terminated when the minimum number of patients in each group was reached. Number 
1 was assigned to the GlideScope® Titanium and number 2 was assigned to the Flexible 
Intubation Video Endoscope® (FIVE). Both devices are routinely used successfully as the first 
choice in this patient group in our clinic. Randomization was concealed in a sealed envelope 
from the operator and the operator was informed after parental consent to participate in the 
study was obtained. Endotracheal intubation was performed by 2 faculty members who were 
experts in the field. Since faculty members would not know the assigned intubation device 
before the patient was taken to the operating room, both devices were kept ready in the room. 
In randomized patients, GlideScope® Titanium (Verathon) or Flexible Intubation Video 
Endoscope® (FIVE) 11301 abx, 2.85 mm (Storz) devices were compared in terms of intubation 
success as the primary outcome and our specified secondary outcome measures.  
After patients were monitored with routine monitoring (SpO2, noninvasive blood pressure, 
ECG, pulse), induction was applied in accordance with the clinical experience of the operator 
and intubation was started with the endotracheal tube selected in accordance with the clinical 
experience of the relevant operator. As a standard in our center, patients with Pierre Robin 
Sequence are taken to the operating room without premedication in order to avoid possible 
respiratory complications. Before anesthesia induction, vascular access is evaluated, and if 
appropriate, vascular access is established with a 24-26 Gauge IV cannula before induction or 
following induction according to the preference of the responsible anesthesiologist. Before 
anesthesia induction, preoxygenation with 100% oxygen is routinely applied and apneic 
oxygenation is applied with various techniques appropriate for the patient at all stages of the 
procedure. In anesthesia induction, 8% sevoflurane, 1 mg/kg methylprednisolone, 0.8-1.0 
mg/kg rocuronium are used in 80% oxygen - 20% air mixture. Dexmedetomidine or 
remifentanil infusion is preferred as analgesic. Long-acting opioids are avoided as a standard 
approach in this patient group. Following standard two-handed AND technique mask 
ventilation, intubation is performed, and the intubation technique was selected together with 
the randomization method specified in our study.  
If GlideScope® Titanium was to be used, a 50-60° angle was applied with the appropriate stylet 
and the appropriate one was selected from the 3 pediatric blade sizes according to the clinical 
experience of the operator. If Flexible Intubation Video Endoscope® (FIVE) was to be used, 
the appropriate endotracheal tube was loaded into the bronchoscope and made ready. The size  

 
and selection of the endotracheal tube to be used were not changed for the purpose of the study. 
The operator used the selection he/she made routinely for the patient according to his/her body 
weight and physical development. The number of attempts for successful intubation and the 
duration were recorded by an unblinded research assistant. The chronometer was started when 
the FFB or the videolaryngoscope started to pass through the patient's mouth/nose and the 
chronometer was stopped when the ventilation of the lungs was confirmed with the end tidal 
carbon dioxide trace and this time was recorded as the successful intubation time. The time 
between the FFB or the videolaryngoscope passing through the mouth/nose and the best glottic 
view was obtained was recorded as the best glottic visualization time. The operator reported the 
percentage of glottic opening score (POGO) and Cormack Lehane scores after obtaining the 
best glottic visualization in the Glidescope group. In accordance with standard clinical practice, 
the operator was allowed to perform optimal external laryngeal manipulation as required during 
laryngoscopy. Endotracheal tube passage time was defined as the intubation time minus the 
best glottic visualization time and was recorded. Failed intubation was defined as an intubation 
attempt exceeding 120 seconds or removal and repositioning of the airway device from the 
mouth/nose or esophageal intubation. If the intubation attempt exceeded 120 seconds or the 
patient's SpO2 value fell below 85% and/or bradycardia occurred at any stage of the procedure, 
the attempt was planned to be terminated if it was ongoing and mask ventilation of the patient 
was provided. Airway management after unsuccessful intubation was managed in accordance 
with the difficult airway algorithm under the responsibility of the faculty member in charge. 
Complications during the attempt were recorded. Complications were determined as 
esophageal intubation, desaturation defined as SpO2<90%, airway bleeding, soft tissue 
damage, bradycardia (heart rate below 90 beats/min), systolic hypotension (below 60 mmHg 
for 0-1 month, 70 mmHg for 1-12 months), dysrhythmia, and cardiac arrest. During this entire 
process, a difficult airway cart and sugammadex were kept ready to be applied in case of 
emergency. In patients who were evaluated to have complications or who might need a 
tracheostomy, a pediatric ENT specialist and a surgical tracheotomy set were present in the 
operating room. All these preparation processes and procedures are routinely applied in this 
manner in our clinic.  
Objective secondary outcomes included intubation time (time between the passage of the FFB 
through the patient's mouth/nose or the video laryngoscope through the patient's mouth and the 
end tidal carbon dioxide trace being seen on the monitor), time to obtain the best glottic 
visualization, endotracheal tube passage time (intubation time - time to obtain the best glottic 
view), whether complications developed (esophageal intubation, desaturation, airway bleeding, 
soft tissue damage, bradycardia, hypotension-hypertension, dysrhythmia, cardiac arrest), CL, 
and POGO scores. Subjectively, ease of use, ease of placement in the oropharynx/nasopharynx, 
quality of vision, and ease of tube advancement were evaluated and recorded by the relevant 
faculty member using a 4-point Likert scale (excellent, good, moderate, poor).  
Parameters recorded in the preoperative period in all patients; √ Age, gender, body weight, 
body surface area (BSA),  
√ Additional diseases, accompanying syndromes, medications used, previous surgeries, ASA 
(American Society of Anesthesiologists) score,  
√ Birth history, postpartum APGAR scores,  
√ Gastroesophageal reflux, feeding disorders,  

 
√ Preoperative airway evaluation; mouth opening (cm), thyromental distance  
(cm), neck range of motion, Frontal Plane-to-Chin Distance (FPCD) measurement for 
evaluation of jaw retraction (cm), respiratory distress in supine position (yes/no), oxygen 
requirement (yes/no), hypotonia (yes/no), history of intubation-tracheostomy (yes/no), 
intensive care unit admission (yes/no), history of Obstructive Sleep Apnea (OSA) (yes/no), 
history of aspiration (yes/no), presence of laryngomalacia/tracheal stenosis (yes/no), additional 
physical examination findings,  
√ Results of previous bronchoscopic evaluations, if any, computed tomography imaging 
(cranial/thoracic), magnetic resonance imaging (cranial/thoracic), swallowing tests, 
echocardiography images and polysomnography  
Statistical Analysis  
IBM SPSS Statistics ver. 25 (IBM Corporation, Armonk, NY, USA) program was used for data 
analysis. Whether the distribution of quantitative variables was distributed close to normal was 
examined with the Shapiro-Wilk test, and whether the assumption of homogeneity of variances 
was met was examined with the Levene test. Descriptive statistics were expressed as median 
(25th percentile-75th percentile) for quantitative variables, while qualitative variables were 
shown as number of cases and (%). As a result of the goodness-of-fit tests, the significance of 
the differences between the groups in terms of variables for which the parametric test statistics 
assumptions were not met was examined with the Mann Whitney U test. In the analysis of 
categorical data, if the expected frequency was below 5 in at least 1⁄4 of the cells in 2x2 cross 
tables, the categorical data in question were evaluated with Fisher's exact probability test, and 
when the expected frequency was between 5-25, the Continuity Corrected χ2 test was used. 
RxC (in case at least one of the categorical variables in the row or column has more than two 
results) in the cross tables, if the expected frequency is below 5 in at least 1/4 of the cells, the 
categorical data in question were evaluated with the Fisher Freeman Halton test. The results 
were considered statistically significant for p<0.05.  
Power Analysis  
It is not known exactly how much the difference in intubation time is significant in the clinic. 
There are very few studies in the literature on this subject in pediatric patients and in the patient 
group with PRS.  
In a study conducted by Fiadjoe et al. on a pediatric PRS mannequin, GlideScope Cobalt 
videolaryngoscope and FFB were compared in terms of their success in the first intubation 
attempt and no difference was found (88.3% vs. 85%, respectively, p=0.59). Although there 
was a statistically significant difference in intubation time between the two groups, this 
difference was not considered clinically significant (median 30.9 s for FFB and 25.1 s for GCV, 
p=0.04). It was interpreted that significant adverse cardiopulmonary events such as arterial 
oxygen desaturation, bradycardia and hypotension were unlikely to occur during this period.  
Again, Fiadjoe et al. In a study conducted by in a pediatric patient group, Glidescope 
videolaryngoscope and conventional direct laryngoscope were compared in terms of intubation 
success and intubation time. In this study, the significant endotracheal intubation time 
difference was accepted as 10 seconds. In our study, based on the existing literature studies and 
our clinical experience, the significant endotracheal intubation time difference was accepted as 

 
10 seconds, and the total sample size was calculated as 46 patients, with 23 patients in each 
group for α=0.05 and 90% power. Patient recruitment continued until the minimum number of 
patients in each group was reached.  
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
INFORMED CONSENT FORM 
PARENT INFORMATION FORM FOR RESEARCH STUDY 
(Patient Group) 
 
(Physician’s Explanation) 
We are conducting a research study titled "Comparison of Intubation Success Between 
GlideScope® Titanium (Verathon) and Flexible Intubation Video Endoscope® (FIVE, Storz) 
in Infants with Pierre Robin Sequence," led by Associate Professor Dr. Aysun ANKAY 
YILBAŞ. With your approval, we propose to include your child in this study. Before you make 
your decision, we would like to provide you with detailed information about the study. If, after 
reading and understanding this information, you agree for your child to participate, please sign 
the form. 
As part of standard care, patients are routinely connected to a ventilator to maintain respiration 
following general anesthesia. Before connecting to the ventilator, a tube is inserted into the 
windpipe using specific tools, a procedure known as intubation. For patients where intubation 
is challenging, methods such as video laryngoscopy or flexible fiberoptic bronchoscopy are 
employed. The purpose of this study is to compare the success rates of video laryngoscopy and 
flexible fiberoptic bronchoscopy for intubation in patients with Pierre Robin Sequence, where 
difficult intubation is anticipated. If you approve your child’s participation, one of these two 
devices, which are already routinely used, will be employed for intubation after anesthesia is 
administered. If you do not approve, one of these devices will still be used as part of standard 
care. There is currently no study proving the superiority of one device over the other in patients 
with Pierre Robin Sequence. The aim of this study is to determine the intubation success rate 
of these devices by randomly assigning one for use during your child’s intubation. 
Random assignment in our study means that the likelihood of your child being intubated with 
either the GlideScope® Titanium or the Flexible Intubation Video Endoscope® (FIVE, Storz) 
is equal. Participants will be divided in a 1:1 ratio for this purpose. Randomization will be 
carried out by a research assistant using a computer to generate random numbers 1 and 2. 
Number 1 will be assigned to GlideScope® Titanium, while Number 2 will be assigned to 
Flexible Intubation Video Endoscope®. The selected device will be concealed in a sealed 
envelope and disclosed to the attending physician only after parental consent is obtained. 
Your participation in this study, conducted by the Department of Anesthesiology and 
Reanimation at Hacettepe University Faculty of Medicine, is important for the success of the 
research. However, if you do not consent, one of these two devices will still be used as part of 
routine care. 
No procedural changes will be made specifically for the study. The procedure deemed 
appropriate by your responsible anesthesiologist will still be implemented. If you agree to 
participate in the study, routine data recorded during your child’s surgery will be documented 
by Associate Professor Dr. Aysun ANKAY YILBAŞ, Professor Dr. Özgür CANBAY, or a 
physician assigned by them. No additional tests, medications, or procedures will be conducted 
during the surgery. The study will begin after routine preoperative data is recorded and 
anesthesia is administered, continuing until the completion of the intubation procedure. 

 
Between April 2021 and August 2022, 46 infants under the age of 18 months, who meet the 
eligibility criteria and whose parents provide informed consent, will be included in the study. 
You will be promptly informed of any new information that may affect your willingness to 
continue participation in the study. 
For patients with anticipated difficult intubation, intubation will be performed using the most 
commonly used and gold-standard devices, as well as by the most experienced faculty 
members. Throughout the procedure, all routine and emergency medications and equipment 
expected to be required will be kept ready. If a more advanced procedure, such as tracheostomy 
(a direct access to the windpipe through the skin), becomes necessary, a pediatric 
otolaryngologist will be present. The study does not involve any application that would 
necessitate this procedure in your child. However, during normal procedures, such preparations 
are routinely made in our clinic to ensure your safety in case of emergencies. 
Your child will not undergo any additional procedures, and if conditions arise that would 
typically prevent surgery, your child may be excluded from the study with your knowledge. 
No procedural changes will be made specifically for the study. Therefore, aside from the routine 
risks mentioned above, your child will not be subjected to any additional harm due to the study. 
Similarly, as no changes to the standard procedure are made for the study, participation will not 
provide any additional benefit to your child. 
You will not be charged any fees for your child’s participation in this study. Additionally, no 
compensation will be provided to you for consenting to your child’s participation. Medical 
information regarding your child will be kept confidential but may be reviewed by personnel 
monitoring the quality of the study, ethics committees, or official authorities if necessary. Data 
obtained from the study may be used for scientific publications without revealing names or 
identifying information. 
You may refuse to have your child participate in this study. Participation in this research is 
entirely voluntary, and your refusal will not result in any changes to your child’s treatment. You 
also have the right to withdraw your consent at any stage of the study. 
(Parent/GuardianDeclaration) 
I have been informed about the research study conducted by Associate Professor Dr. Aysun 
ANKAY YILBAŞ at Hacettepe University Faculty of Medicine, Department of Anesthesiology 
and Reanimation, and its details have been conveyed to me. Following this information, my 
child has been invited to participate in this research as a “participant.” 
If I agree to my child’s participation in this study, I believe that the confidentiality of my child’s 
information, which must remain between me and the physician, will be handled with great care 
and respect throughout the study. I have been adequately assured that my child’s personal 
information will be protected with care during the educational and scientific use of the study 
results. 
I will not bear any financial responsibility for expenses related to the study. No payment will 
be made to me. 

 
I have been provided assurances that in the event of any health issues arising directly or 
indirectly from the study, all necessary medical interventions will be provided (and I will not 
incur any financial burden for these interventions). 
Should I encounter any health issues during the study, I know I can reach Associate Professor 
Dr. Aysun ANKAY YILBAŞ at 03123051250 (office) or 05325546801 (mobile), Research 
Assistant Begüm ERCAN at 03123051250 (office) or 05387226672 (mobile), or the Hacettepe 
University Faculty of Medicine, Department of Anesthesiology and Reanimation. 
I am not obligated to consent to my child’s participation in this study and may refuse. I have 
not faced any coercion regarding my child’s participation in this study. If I refuse my child’s 
participation, I understand that this will not harm my child’s medical care or the relationship 
with the physician. 
If my child participates in the study, I am aware that my child will not be subjected to any 
additional harm from the study and that participation will not provide any additional benefit. 
I have fully understood all the explanations provided to me. After an independent period of 
consideration, I have decided to allow my child to participate in this research project as a 
“participant.” I accept this invitation with great satisfaction and willingness. 
A signed copy of this form will be provided to me. 
Parent’s Name and Surname: 
Relationship to the Participant: 
Date: 
Signature: 
Witness to the Interview: 
Name and Surname: 
Date: 
Signature: 
Physician Conducting the Interview: 
Name, Surname, Title: 
Date: 
Signature: 
Principal Investigator: Associate Professor Dr. Aysun ANKAY YILBAŞ 
Date: 
Signature: