Observation of Clinical Effect of New Oropharyngeal Airway in Patients With Obstructive Sleep Apnea Hypoapnea Syndrome During Painless Gastroenteroscopy
Phase: NA
Conditions: OSAHS, Gastrointestinal Endoscopy, Airway Complication of Anesthesia
Sponsor: Jianbo Wu

Research Protocol
(Version No. 2.3 Version Date: 2024.08.02)
Project Name
：Observation of the clinical effect of a new
oropharyngeal airway in patients with obstructive sleep
apnea hypopnea syndrome during painless gastroenteroscopy
Department：
Anesthesia and perioperative Medicine
Main Investigator：
Jianbo Wu

Investigator Statement and Protocol signature page
As the principal investigator of this research project,Will be guided by the
ethical principles of the Guidelines on the Issuance of Ethical Review of
Life Sciences and Medical Research Involving Humans (2023), the
Ethical Review of Biomedical Research Involving Humans (2016), the
WMA Declaration of Helsinki (2013) and the CIOMS International
Ethical Guidelines on Biomedical Research on Humans (2002) and the
GCP,The study shall be conducted in accordance with the requirements
of the protocol approved by the Ethics Committee under the guidance of
the quality Management Practice for drug clinical research, in order to
ensure the scientific study and protect the health and rights of the study
participants.
signature：________________
Date：________________

Scheme summary
Scheme title
Observation of clinical effect of new oropharyngeal
airway in patients with obstructive sleep apnea hypopnea
syndrome during painless gastroenteroscopy
Version number/version
date
Version Number 2.3 Version Date: 2024.08.02
Main Investigator
Jianbo Wu
Nature of the study
Prospective
andomized, controlled clinical intervention study
Objective To
investigate
the incidence of hypoxia in patients with obstructive
sleep apnea hypopnea syndrome who underwent painless
gastroenteroscopy using a new type of oropharyngeal
airway.
Sample size
130
Subjects
Obstructive
sleep apnea hypopnea syndrome patients undergoing
painless gastroenteroscopy
Inclusion criteria
(1) Age 18-65 years old (2) evidence of polysleep
monitoring for diagnosis of OSAHS (3) written informed
consent of patient or family member (4) painless stomach
+ colonoscopy (5) ASA grade I-II
Exclusion criteria
(1) There is a clotting disorder or a tendency to nose and
mouth bleeding, mucosal damage or space
occupation,Patients who cannot perform oropharyngeal
ventilation (2) upper respiratory tract infections such as
mouth, nose or throat (3) fever (core body temperature
≥37.5 ° C) (4) diagnosed pregnancy or breastfeeding (5)
allergy to sedatives such as propofol or devices such as
tape (6) emergency surgery (7) multiple trauma (8)
Breathing air before surgerypO2 < 95% (9) History of
drug and/or alcohol abuse (drinking more than three times
standard alcoholic beverages per day, equivalent to
approximately 10g of alcohol or equivalent to 50g of
Chinese liquor) in the 2 years prior to initiation of the
screening period (10) Patients with prior psychiatric and
neurological conditions:Such as depression, severe central
nervous depression, Parkinson's disease, basal ganglia
disease, schizophrenia, epilepsy, Alzheimer's disease,

myasthenia gravis (11) are currently participating in other
clinical trials
(13) Patients with a history of smoking should not
participate in this trial
Research program
Heart rate, pulse oxygen saturation (SpO2), end-
expiratory carbon dioxide, ECG monitoring, and
noninvasive blood pressure (measured every 3 minutes)
were routinely monitored before anesthesia induction.In
this study, SAS was used to achieve simple
randomization: 1. In the group using the new
oropharyngeal airway (test group), oxygen was
continuously supplied through a catheter connected to the
endoscopic bites until the end of the gastroenteroscopy
before induction of anesthesia.2. In the conventional
endoscopic bite group (control group), oxygen was
continuously supplied through a conventional nasal
catheter before induction of anesthesia and until the end of
gastroenteroscopy.Before anesthesia induction, patients in
the experimental group received 5-6L/min of oxygen for
about 1min through the endoscopic bite connecting
oxygen supply device, and patients in the control group
inhaled 5-6L/min of oxygen for about 1min through the
nasal catheter.Propofol 3mg/kg and sufentanil 7μg were
used to induce anesthesia in both groups.Sufentanil was
given at the beginning of pre-oxygen inhalation, and
propofol was given 1min later. When participants
achieved sufficient sedation (about BIS40), the new
oropharyngeal airway group was placed into the
oropharyngeal airway through the endoscopic bite and
then began gastroscopy.The ordinary endoscopic bite
group began to perform endoscopic operation after
sufficient sedation was achieved.In both groups, 5mg/kg·h
propofol was injected continuously to maintain anesthesia
until the examination was completed.If participants
showed frowning or slight body movement during
diagnosis and treatment, 40 to 50mg of propofol was
added intravenously.If HR < 50 times/intravenous
injection of atropine 0.5mg;MAP < 60mmHg intravenous
hydroxyamine 1mg;When SpO2 < 92%, artificial airway
intervention such as jaw support, assisted breathing or
mask was given.After the examination is completed, the
patient should not leave the examination room until the
MOAA/S is 3-4 points.If the sedation/anaesthesia

Discharge rating scale scores more than 9 points, patients
can be accompanied by relatives and friends.The
incidence of hypoxia (75%≤SpO2 < 90%, ≤60s) and
severe hypoxia (SpO2 < 75% or 75%≤SpO2 < 90%, ≥60s)
during anesthesia were recorded.The incidence of
choking, reflux aspiration and laryngeal spasm were
recorded.The time of intervention was half or
disappearance of end-expiratory carbon dioxide and/or
disappearance of thoracic fluctuation and/or SpO2 < 95%,
that is, open airway manipulation was taken successively
until SpO2≥95%, and the last means of opening the
airway was recorded.The means of opening the airway of
the two groups were the same, including: 1) adjusting the
oxygen flow;2) Lift the lower jaw; 3) Mask ventilation
(pull out the gastroscope if necessary);4) Tracheal
intubation or laryngeal mask for ventilator assisted
ventilation.
Shedding/culling
criteria
After postoperative recovery, patients were assessed
for adverse reactions. The score of discharge scale after
sedation/anesthesia was more than 9 points. Patients could
be accompanied by relatives and friends to leave the
hospital.
Shedding/culling
criteria
Patients who were lost to follow-up, had adverse
events, or voluntarily withdrew from the trial
Early exit criteria
Patients with severe airway spasm, obstruction of
ventilation, inability to effectively improve airway, and
need emergency tracheal intubation or cricothyroid
puncture.
Primary outcome
measure
Incidence of hypoxia (75%≤SpO2 < 90%, ≤60s)
during anesthesia and sedation.
Secondary outcome
measure
1, severe hypoxia (SpO2 < 75% or 75%≤SpO2 <
90%, ≥60s) 2, the incidence of airway intervention 3,
intraoperative dose of additional drugs 4, endoscopist
satisfaction 5, recorded adverse events: choking, laryngeal
spasm and reflux aspiration incidence;Apnea or slow
breathing episodes (defined as respiratory rate ≤6
beats/min);Bradycardia is defined as a heart rate ≤50
beats/min.Serious adverse events such as tracheal
intubation, non-invasive ventilation, use of vasopressors,
and hospitalization are required.

Safety index
1. Primary outcome measures: incidence of hypoxia 2.
Secondary outcome measures: (1) incidence of airway
intervention (2) monitoring of vital signs at different time
points 3. Adverse events: (1) Intraoperative laryngeal
spasm, reflux aspiration, hypotension, hypoxia saturation,
respiratory depression, bradycardia/tachycardia etc. (2)
postoperative:Pharyngeal pain, oropharyngeal
hemorrhage, wake score, etc. 4. Satisfaction: patient,
endoscopist
Statistical analysis
method
SPSS22.0 statistical software package was used for
statistical analysis, and the measurement data were
expressed in the form of mean ± standard deviation (x±S).
Independent sample t test was used for statistical analysis
of the data with normal distribution or transformed data
conforming to normal distribution.For non-normal data,
wilcoxon rank sum test was used to compare inter-group
analyses.Counting data were represented by frequency
(%), and Chi-square test was used for statistical analysis.P
< 0.05 was considered to be statistically significant.
Research progress
plan
1. From July 2024 to August 2024, improve the study
design, formulate relevant CRF tables, pass ethics and
register online;
2. From August 2024 to May 2025, complete case
enrollment;
3. From June 2025 to September 2024, summarize data,
make statistical analysis, and write the paper
Form of
publication of
research results
The results of the study will be published in the form of a
paper, and 1-2 articles included in SCI will be published.

一、Objective
1.Primary outcome measures
To investigate the incidence of novel oropharyngeal airway hypoxia (75%≤
SpO2 < 90%, ≤60s) during anesthesia in patients with obstructive sleep apnea
hypopnea syndrome undergoing painless gastroenteroscopy.
2. Secondary outcome measure
(1) Incidence of severe hypoxia (SpO2 < 75% or 75%≤SpO2 < 90%, ≥60s)
(2) The incidence of airway intervention required
(3) the dosage of additional drugs during the operation was recorded
(4) the satisfaction of endoscopists was recorded
(5) Adverse events were recorded: the incidence of choking, laryngeal spasm and
reflux aspiration were observed;Apnea or slow breathing episodes (defined as
respiratory rate ≤6 beats/min);Bradycardia is defined as a heart rate ≤50
beats/min.Serious adverse events such as tracheal intubation, non-invasive ventilation,
use of vasopressors, and hospitalization are required.

3. Exploratory index
To observe whether the use of a new oropharyngeal airway during anesthesia can
effectively reduce the incidence of adverse events other than hypoxia in patients with
obstructive sleep apnea hypopnea syndrome undergoing painless gastroenteroscopy,
and its safety and efficacy.
Research background
In recent years, gastroscopy has been applied more and more in clinical practice.
It is a new endoscopic examination technology that finds all possible small lesions in
the upper digestive tract (esophagus, stomach, duodenum) of patients through white
light gastroscopy, and performs chemical staining, electron staining, optical/electronic
amplification, targeted biopsy, etc., for suspicious lesions with indistinguable
properties, so as to clarify the nature of the lesions.This technology can improve the
diagnostic rate of early gastric cancer and is a major breakthrough in the early
diagnosis of gastric cancer [1].Compared with ordinary gastroscopy, gastroscopy takes
a longer time (it may take longer if suspicious lesions are found) and intraoperative
airway management is more difficult.
Obstructive sleep apnea hypopnea syndrom (obstructive sleep apnea hypoapnea
syndrome OSAHS) is a kind of to sleep appear periodically in the process of
syndrome characterized by partial or complete obstruction of upper respiratory
tract.Patients with obstruction during the attack, faced with percutaneous arterial
blood oxygen saturation (percutaneousarterialoxygensaturation, SpO2) to reduce the
risk of can also trigger hypercapnia and cardiovascular dysfunction.The global
incidence of OSAS is 4.0% in males and 2.0% in females [2].Sedative drugs inhibit the
response of OSAS patients to external stimuli and may cause pharyngeal muscle
collapse, leading to an increased risk of respiratory adverse events during painless
gastroscopy in this population [3].In fact, OSAS has been identified as an independent
risk factor for endoscopic hypoxia [4].Currently, there is no special oropharyngeal
ventilation
device
used
during
gastroenteroscopy.
Recently,
a
new
type
of
oropharyngeal ventilation channel has been developed and applied in clinic.Compared
with the conventional nasal catheter, the new oropharyngeal airway nasal mask can
better fit the patient's face, ensure the air tightness inside the nose mask and maximize
the oxygen
supply efficiency.
The carbon
dioxide outlet connected
to the
oropharyngeal airway body can not only collect the patient's exhaled gas, but also
reduce the backflow of carbon dioxide gas.It can also access carbon dioxide detection
equipment to monitor the patient's PCO2 at the end of breath in real time [5-6].In order
to evaluate whether the new oropharyngeal airway can reduce the incidence of

hypoxia during painless gastroenteroscopy in general patients, the study was designed
to investigate the safety and efficacy of the new oropharyngeal airway.The new
oropharyngeal airway is composed of nasal plug, biting mouth, oropharyngeal
passage, oxygen supply tube, lanyard and optional accessories carbon dioxide gas
catheter and carbon dioxide collection tube.It is used to prevent airway obstruction
due to retrolingual fall in patients undergoing endoscopic surgery/examination, and to
establish an oropharyngeal airway for study participants while providing nasal oxygen.
【reference】
[ 1 ] MUTO M, YAO K, KAISE M, et al. Magnifying endoscopy simple diagnostic algorithm for early
gastric cancer (MESDA-G) [J]. Dig Endosc, 2016, 28(4): 379-393.
[2] PATIL S P, SCHNEIDER H, SCHWARTZ A R, et al. Adult obstructive sleep apnea:
pathophysiology and diagnosis[J]. Chest, 2007, 132(1): 325-337.
[3] WEATHERSPOON D, SULLIVAN D, WEATHERSPOON C A. Obstructive sleep apnea and
modifications in sedation: an update[J]. Crit Care Nurs Clin North Am, 2016, 28(2): 217-226.
[4] MEMTSOUDIS S G, COZOWICZ C, NAGAPPA M, et al. Society of Anesthesia and Sleep
Medicine guideline on intraoperative management of adult patients with obstructive sleep apnea[J].
Anesth Analg, 2018, 127(4): 967-987
[5] Zi Tingting, Zhang Jianmin, Xin Zhong.Application of oropharyngeal airway combined with mask
mechanical ventilation in children undergoing day surgery [J]. Journal of Clinical Anesthesiology,,
2015,31(1):57-59
[6] Qi Wenyu, ZHAO Ping. Progress of nasopharyngeal airway in general anesthesia [J]. Chinese
Journal of Advanced Medical Education, 2020(01):90-91-92.
Test basis
1. Preliminary literature and experimental basis of this study:
Obstructive sleep apnea hypopnea syndrom (obstructive sleep apnea hypoapnea
syndrome OSAHS) is a common sleep-related breathing disorder, as caused by
pharyngeal
cavity
stenosis
during
the
period
of
sleep
apnea
and
low
ventilation.During the time-consuming gastroscopy, patients have certain difficulties
in airway management due to the narrow anatomical position of the upper respiratory
tract, enhanced local soft tissue collapse, and occupation of the oropharyngeal airway
by endoscopist [1-2], and the risk of adverse respiratory events is also higher.At present,
the commonly used airway management method is nasal catheter oxygen inhalation.It

has been reported that although nasal high-flow oxygen therapy can reduce the
incidence of hypoxia in ordinary patients during painless gastroscopy, its effect on
improving
ventilation
in
OSAHS
patients
is
relatively
limited
[3-4].Painless
gastroenteroscopy has been widely used in the diagnosis and treatment of digestive
tract diseases, during which the occurrence of intraoperative hypoxia is also
concerned.At present, nasal catheter oxygen delivery is widely used clinically to
prevent the occurrence of intraoperative hypoxia [5]. In addition, studies have shown
that carbon dioxide monitoring can reduce the incidence of hypoxemia, but cannot
avoid the occurrence of severe hypoxia [6].However, hypoxia still occurred during the
operation (8%) after the application of low flow nasal catheter [7].Previous studies
have shown that although new devices such as high-flow nasal catheter oxygen
inhalation and supragtal airway injection technology can reduce the incidence of
hypoxia, they are difficult to be widely used in clinical practice due to high cost and
inconvenience [8,9].Supraglotic jet ventilation devices can reduce the incidence of
hypoxia from 9% to 3% [10], but they are costly, prone to adverse events such as
nosebleedings, and troublesome to use.High oxygen flow can increase FiO2 to 1.00
and maintain slight PEEP, and produce the effect of dead cavity flushing [11], which
further reduces the incidence of hypoxia and increases the minimum oxygen
saturation [12], but it is expensive and prone to adverse reactions such as airway
dryness, pharyngeal pain and barotrauma [9].The oropharyngeal airway is an important
airway auxiliary device for short-term airway management during the perianesthetic
period, which can provide patients with an unobtrusived airway during autonomous
ventilation [12].The oropharyngeal vent has been proven to be successfully used in
infants, the elderly and MRI examinations, and can be used in short outpatient surgery
instead of laryngeal mask
[13].The oropharyngeal airway has a low incidence of
pharyngeal trauma and laryngeal pain immediately after surgery, requiring a shorter
exposure time of inhaled anesthetic and a lower concentration of propofol to
successfully place it [14].During the operation to preserve spontaneous breathing, the
oropharyngeal airway is introduced as a ventilation device [15].The new oropharyngeal
airway can accept the implantation of gastroscopy and provide oxygen to patients
without affecting the operation at the same time. In order to explore whether the new
oropharyngeal airway can provide better oxygen to patients undergoing painless
gastroenteroscopy and reduce the incidence of hypoxia during the operation, we have
drafted this study and explored the safety of the new oropharyngeal airway in painless
gastroenteroscopy.
【reference】

[1] MUTO M, YAO K, KAISE M, et al. Magnifying endoscopy simple diagnostic algorithm for early
gastric cancer (MESDA-G) [J]. Dig Endosc, 2016, 28(4): 379-393.
[2] ROSSI V A, STRADLING J R, KOHLER M. Effects of obstructive sleep apnoea on heart
rhythm[J]. Eur Respir J, 2013, 41(6): 1439-1451.
[3] LIN Y X, ZHANG X Q, LI L Z, et al. High-flow nasal cannula oxygen therapy and hypoxia during
gastroscopy with propofol sedation: a randomized multicenter clinical trial[J]. Gastrointest Endosc,
2019, 90(4): 591-601.
[4] RICCIO C A, SARMIENTO S, MINHAJUDDIN A, et al. Highflow versus standard nasal cannula
in morbidly obese patients during colonoscopy: a prospective, randomized clinical trial[J]. J Clin
Anesth, 2019, 54: 19-24.
[5] Ebert TJ, et al. The effectiveness of oxygen delivery and reliability of carbon dioxide waveforms: a
crossover comparison of 4 nasal cannulae. Anesth Analg. 2015. 120(2): 342-348.
[6] Beitz A, et al. Capnographic monitoring reduces the incidence of arterial oxygen desaturation and
hypoxemia during propofol sedation for colonoscopy: a randomized, controlled study (ColoCap Study).
Am J Gastroenterol, 2012. 107(8): 1205-1212
[7] Lin Y X, Zhao Y H, Wang X J, Incidence and risk factors of hypoxemia during painless
gastroscopy under propofol sedation.Diagnostics theory and practice, 2020. 19(06): 594-599.
[8] Santer P, et al. High-flow nasal oxygen for gastrointestinal endoscopy improves respiratory safety.
Br J Anaesth, 2021. 127(1): 7-11.
[9] Goudra B, et al. Recent Developments in Devices Used for Gastrointestinal Endoscopy Sedation.
Clin Endosc, 2021. 54(2): 182-192.
[10] Qin Y, et al. Supraglottic jet oxygenation and ventilation enhances oxygenation during upper
gastrointestinal endoscopy in patients sedated with propofol: a randomized multicentre clinical trial. Br
J Anaesth, 2017. 119(1): 158-166.
[11] Gu WJ, et al. High flow nasal oxygen versus conventional oxygen therapy in gastrointestinal
endoscopy with conscious sedation: Systematic review and meta-analysis with trial sequential analysis.
Dig Endosc, 2022. 34(6): 1136-1146.
[12] Brimacombe J, et al The cuffed oropharyngeal airway for spontaneous ventilation anaesthesia.
Clinical appraisal in 100 patients. Anaesthesia, 1998. 53(11): 1074-1079.
[13] Yavascaoglu B, et al. Cuffed oropharyngeal airway as a suitable alternative to the laryngeal mask
airway for minor outpatient surgery. Eur J Anaesthesiol, 2002. 19(3): 203-207.
[14] Casati A, et al. Do we need new supraglottic devices? Clinical appraisal of the cuffed
oropharyngeal airway (COPA). Minerva Anestesiol, 1999. 65(12): 823-830.
[15] Audu PB, et al. Use of cuffed oropharyngeal airway (COPA) for awake intracranial surgery. J
Neurosurg Anesthesiol, 2004. 16(2): 144-146.
2. Study participant selection basis

By combining precision medicine with comfortable diagnosis and treatment,
painless gastroscopy has become the first choice for the diagnosis and treatment of
upper gastrointestinal diseases.Propofol is widely used in painless gastroscopy
because of its rapid onset and rapid elimination, but the incidence of hypoxemia is
high, which is related to the easy cause of apnea and abnormal ventilation of patients
with propofol.Obstructive sleep apnea hypopnea syndrome is a potentially dangerous
disease, and is one of the common causes of sudden cardiac death and stroke in
clinical practice [1].OSAHS patients, especially those with severe (AHI > 40), have
repeated apnea at night, resulting in a long-term state of low blood oxygen at night
and serious lack of sleep, and their tolerance to surgery and anesthesia drugs has
decreased significantly, especially when accompanied by hypertension, asymptomatic
cerebral embolism and other complications, the risk of surgery is greater.Death after
operation has been reported at home and abroad [2].However, most severe OSAHS
patients not only have palatopharyngeal plane obstruction, but also have multiple
plane obstruction at the same time.In order to improve the surgical success rate of
OSAHS patients with multiplane obstruction of upper airway, it is necessary to
implement comprehensive treatment based on simultaneous combined multiplane
surgery for severe OSAHS patients with multiplane obstruction to improve the
curative effect, which has been a consensus at present.However, this may cause
higher level of postoperative upper airway asphyxia, which puts forward higher
requirements for postoperative upper airway management.In order to improve the
surgical success rate of OSAHS patients with multi-plane obstruction of upper airway,
reduce
postoperative
respiratory
complications,
and
alleviate
patients'
pain,
nasopharyngeal airway airway and oropharyngeal airway airway are generally
recognized as the best methods for postoperative respiratory management.Due to a
large amount of fat accumulation in the chest and abdomen of the patient, the total
compliance of the chest and lungs is reduced. The lower position of the intubation
head under general anesthesia and abdominal surgery will lead to further upward
movement of the diaphragm, resulting in decreased thoracic volume, reduced total
compliance of the chest and lung, decreased functional residual chest volume,
premature closure of small airways, and reduced number of ventilation alveoli.At the
same time, the abdominal venous blood is squeezed into the thoracic vein during
abdominal surgery, resulting in the accumulation of blood in the chest and the
increase of physiologically ineffective cavities, resulting in a decrease in the
ventilation/blood flow ratio [3].Airway management in OSA patients is difficult due to
excessive fat accumulation in the front neck, lower neck and chest, which leads to
limited movement of the neck. In addition, there may be excess tissue in the throat,
which leads to airway stenosis.Especially for patients with OSA, induced intubation

must be avoided and conscious intubation under surface anesthesia or guided
intubation under fiberoptic bronchoscope should be adopted [4].To sum up, airway
management in obese patients is a clinical focus and difficulty. In order to reduce the
trauma of patients and promote ERAS, endotracheal intubation is often not possible
during the operation of painless gastroenteroscopy. Therefore, it is a topic worthy of
our exploration to not only meet the comfort requirements of patients, but also ensure
the safety of patients during the whole perioperative period.Whether the birth of new
oropharyngeal airway can solve the ventilation problem of obese patients during
anesthesia is the significance of this research.
【reference】
[1] Zeng Shiying, ZHANG Longyu, ZHAO Xinyuan, ZHANG Jin, BAI Junyun.Effect of nasal
continuous positive airway pressure on patients with obstructive sleep apnea syndrome [J].World
Journal of Sleep Medicine,2021,8(03):537-538.
[2] Pang Congyi, Yi Jingde.Effect of nasal continuous positive airway pressure on patients with
chronic heart failure complicated with obstructive sleep apnea hypopnea syndrome [J].Medical food
therapy and health ,2021,19(12):48-49.
[3] Liu Xiaojie, Li Dajiang, Ning Jishun, et al.A case of severe hypoxemia in obese patients
undergoing radical general anesthesia for colon cancer [J]. Journal of Clinical Anesthesiology,
2016,32(05):518.
[4] Hang Yannan. Handbook of Contemporary Anesthesia [M]. 2nd Ed.Beijing: World Book
Publishing House, 2011：358-363.
Research content：
1. Study population
The principal investigator was responsible for recruitment under strict control,
and 130 patients with obstructive sleep apnea hypopnea syndrome (diagnosed as
OSAHS
by
polysomnography
monitoring)
who
underwent
painless
gastrocolonoscopy from today were selected. They were informed and consented to
this clinical trial.
2. Sample size calculation：
According to the pre-test results, the incidence of hypoxia in the test group and
the control group were 0.2 and 0.5, respectively. The sample size was calculated using
PASS software, and the bilateral test level α=0.05 and the test efficacy power=0.9

were set. 52 cases were required in each group according to the incidence of hypoxia,
and 65 cases in each group were calculated after considering 20% shedding rate,
totaling 130 cases.
3. Specific research content：
Study participants entered the examination room to establish intravenous access,
using 2% lidocaine gel 5ml containing mouth cavity and pharynx.Heart rate (HR),
pulse oxygen saturation (SpO2), end-expiratory carbon dioxide, IPI (composite lung
index), ECG monitoring, and non-invasive blood pressure (measured every 2.5
minutes) were routinely monitored before anesthesia induction.Ask patient to lie on
left side.
In this study, the investigators planned to implement simple randomization using
SAS:
(1) The group using the new oropharyngeal airway (test group) : Oxygen was
continuously supplied through a catheter partially attached to the endoscopic mouth
before induction of anesthesia until the end of gastroenteroscopy.
(2) In the conventional endoscopic bite group (control group), oxygen was
continuously supplied through a common nasal catheter before induction of anesthesia
until the end of gastroenteroscopy.
The
entire
trial
operation
process
was
completed
by
the
investigators
participating in the clinical trial.Before induction of anesthesia, study participants in
the experimental group received 5-6L/min of oxygen for about 1 minute through an
endoscopic biting oxygen supply device, and participants in the control group inhaled
5-6L/min of oxygen for about 1 minute through a nasal catheter.Propofol 3mg/kg and
sufentanil 7μg were used to induce anesthesia in both groups.Sufentanil was given at
the beginning of pre-oxygen inhalation, and propofol was given 1min later. When
participants achieved sufficient sedation (about BIS40), the new oropharyngeal
airway group was placed into the oropharyngeal airway through the endoscopic bite
and then began gastroscopy.The ordinary endoscopic bite group began to perform
endoscopic operation after sufficient sedation was achieved.In both groups, 5mg/kg·h
propofol was injected continuously to maintain anesthesia until the examination was
completed.If participants showed frowning or slight body movement during diagnosis
and treatment, 40 to 50mg of propofol was added intravenously.If HR < 50
times/intravenous
injection
of
atropine
0.5mg;MAP
<
60mmHg
intravenous
hydroxyamine 1mg;When SpO2 < 92%, artificial airway intervention such as jaw
support, assisted breathing or mask was given.After the examination, study
participants were not allowed to leave the examination room until they had a

MOAA/S score of 3-4.If the sedation/anaesthesia Discharge rating scale scores more
than 9 points, patients can be accompanied by relatives and friends.The incidence of
hypoxia (75%≤SpO2 < 90%, ≤60s) and severe hypoxia (SpO2 < 75% or 75%≤SpO2
< 90%, ≥60s) during anesthesia were recorded.The incidence of choking, reflux
aspiration and laryngeal spasm were recorded.The time of intervention was half or
disappearance of end-expiratory carbon dioxide and/or disappearance of thoracic
fluctuation and/or SpO2 < 95%, that is, opening the airway successively until
SpO2≥95%, and recording the last means of opening the airway.
The means of opening the airway of the two groups were the same, including: 1)
adjusting the oxygen flow;2) Lift the lower jaw;3) Mask ventilation (pull out the
gastroscope if necessary);4) Tracheal intubation or laryngeal mask for ventilator
assisted ventilation.
Patient satisfaction scales usually use a 0-10 scale, where 0 is very dissatisfied
and 10 is very satisfied.Patients are asked to select a number on the rating scale to
indicate satisfaction with medical services or pain relief methods based on their actual
experience;
The doctor satisfaction scale also uses a 0-10 scale, with 0 being very dissatisfied
and 10 being very satisfied.Endoscopists need to select a corresponding number on
the score sheet according to their actual experience to indicate whether the patient is
satisfied with the cooperation and response of the operation process.
五、Research Methods
1. Inclusion criteria
130 patients with obstructive sleep apnea hypopnea syndrome who underwent
painless gastroenteroscopy in our hospital from now on were selected.
1.1 Inclusion criteria:
1) Age 18-65 years old
2) evidence of OSAHS diagnosed by polysleep monitoring
3) written informed consent of patient or family member
4) painless stomach + colonoscopy
5)ASA grade I-II diagnostic criteria for OSAHS: 1) OSAHS diagnosed by
polysleep monitoring (PSG).2. For patients who come to make an appointment for

gastroenteroscopy, the risk assessment results can be given through questionnaires
combined with the major risk factors, physical examination, clinical symptoms, etc.,
which have been identified.For example, the STOP-BANG questionnaire evaluated
the risk through eight items including snoring, fatigue, observed apnea, blood pressure,
body mass index, age, neck circumference, and gender.For those at higher risk, a
diagnosis can be made by providing free polysomnography monitoring (PM) with
informed consent.
1.2 Exclusion criteria:
1) Patients with blood clotting disorders or a tendency to oropharyngeal bleeding,
mucosal damage or space occupation, difficulty in placing oropharyngeal airway, etc.,
who cannot perform oropharyngeal airway ventilation;
2) Upper respiratory tract infections such as mouth, nose or throat;
3) Fever (core body temperature ≥37.5℃);
4) a confirmed diagnosis of pregnancy or breastfeeding;
5) Allergic to sedatives such as propofol or equipment such as tape;
6) Emergency surgery;
7) Multiple trauma;
8) SpO2 < 95% before operation;
9) A history of drug and/or alcohol abuse within 2 years prior to the start of the
screening period;(Drinking more than three times standard alcoholic beverages per
day, equivalent to about 10g of alcohol or equivalent to 50g of Chinese liquor);
10) Patients with previous psychiatric and neurological diseases, such as
depression, severe central nervous depression, Parkinson's disease, basal ganglia
disease, schizophrenia, epilepsy, Alzheimer's disease, myasthenia gravis;
11) Currently participating in other clinical trials;
12) Patients who are deemed unfit by the investigator to participate in the trial;
13) Patients with a history of smoking should not participate in this study.
1.3 Exclusion/removal criteria
1) The patient voluntarily withdrew the informed consent
2) the operation was cancelled

2. Grouping of study participants:
This study planned to implement simple randomization with SAS: Group 1 was
the group using the new oropharyngeal airway (experimental group);The other group
was the control group (control group).
3. Blinded/unblinded patients This study was an open trial, and no blinded
method was used.
4. Remedial and supportive treatment (necessary treatment measures for the
occurrence of SAE related to the study)
(1) Continue to inject propofol with a range of 5ml to achieve the appropriate
depth of anesthesia again if coughing, limb struggle and other conditions occur during
the procedure;
(2) If severe airway spasm, obstruction of ventilation occur during the operation,
and the airway cannot be effectively improved, measures such as mask pressure
oxygen, emergency tracheal intubation or cricothyroid puncture should be taken.In the
event of intraoperative emergencies and accidents, patients should be treated
primarily, and patients should be put in the first place in accordance with clinical
routine rescue and treatment of study participants.
5. Study Participant Early withdrawal/Trial termination criteria: Unconditional
termination of the trial at any time when a study participant proposes to withdraw
from the trial, while still guaranteeing patient safety throughout the process.
Research program
1. Study Participant Management
1) Study participant recruitment methods:The staff participating in this clinical trial
was responsible for recruitment under the control of the principal investigator. 130
patients with obstructive sleep apnea hypopnea syndrome (diagnosed as OSAHS by
polysomnography monitoring) who met the enrollment criteria and intended to
undergo painless gastrocolonoscopy in our hospital were initially screened, and the
recruitment materials were distributed to the study participants and their families.
2) Informed consent process: When enlisting study participants, inform study
participants and their families of the detailed contents of the study, possible risks and
benefits (see informed consent for details) in accordance with the content and
requirements of informed consent, obtain consent from study participants and their
families, and sign informed consent before anesthesia induction.

3) Check the admission criteria: Participants were selected strictly according to the
admission and exclusion criteria, and should be checked before entering the operating
room and before anesthesia induction.
2. Safety evaluation procedure: Study participants with oropharyngeal tumor,
inflammation, infection, ulcer and other bleeding risk withdrew from the test, and
ventilation should not be used.
3. Termination and withdrawal procedures: Study participants with severe airway
spasm, obstruction of ventilation, or failure to effectively improve airway, requiring
emergency tracheal intubation or cricothyroid puncture, should immediately take life-
saving measures and automatically withdraw from the study.
4. This study was conducted in collaboration with the Department of Anesthesia and
Perioperative Medicine, the Department of Digestive endoscopy, and the Sleep
Disorder Diagnosis and Treatment Center of Neurology.In the stages of study
participant recruitment and trial conduct, tasks are allocated according to the
professional background and skills of each team member to ensure that everyone's
responsibilities are clear and they can work together.
The beginning and end of the experiment
Start: Trial is expected to begin after ethical review in July-August 2024.
End: Clinical trial phase is expected to end in May-June 2025.
Clinical criteria for early termination of trials
Criteria for termination: The study should be terminated if participants had severe
airway spasm, obstruction of ventilation, or inability to effectively improve airway, or
if
emergency
tracheal
intubation
or
cricothyroid
puncture
were
required.Or
withdrawal of informed consent by study participants requires termination of the trial.
Data security and monitoring Programme
1. Overview of data Management methods Original records refer to all kinds of data,
text, charts, pictures and other original materials directly recorded or statistically
formed by means of experiment, observation, investigation or data analysis in the
process of clinical and scientific research.The original record is the direct record of
the original data obtained in the process of scientific experiment, which can be used
as the important basic data for in-depth research in different periods.The original test
records should be able to reflect the most real and original conditions in the test, and

must be timely, true, accurate and complete, prevent omission and random alteration,
and prohibit forgery and fabrication of data. The original test data and materials
should be retained for at least 10 years after the complete end of the test.
2. Reporting and collection of adverse events and serious adverse events An adverse
event is any adverse symptoms and abnormal signs that occur after the application of
an intervention, whether or not the trial has a causal relationship.Any adverse events,
including those voluntarily provided by study participants or queried by investigators
or detected by monitoring, should be recorded on the CRF and actively managed and
followed up closely until remission or stabilization.All adverse events must be tracked,
and the case report form should be filled in by the investigator in time to ensure that
the content is accurate and the summary is timely.CRF form should not be altered in
general, if there are errors that need to be modified, you should sign the amendment
and sign the amendment date.Adverse event reports should include: adverse event
content (symptoms, signs, abnormal indicators), start and end dates, evaluation of
adverse event severity (mild, moderate, alarming), action taken (no action, stop
intervention, treatment), adverse event outcome (no adverse prognosis, hospitalization,
permanent neurological deficits, death).Any serious adverse event occurring in the
course of clinical research, in addition to timely active and effective treatment, the
investigator should report the serious adverse event to the ethics committee of the
research unit within 24 hours after learning about it.At the same time, the serious
adverse event form must be filled in to record the occurrence time, severity, duration,
measures taken and outcome of serious adverse events.
3. Medical safety measures If adverse events occur during the study, regardless of
whether they are causally related to the intervention measures, the principal
investigator should immediately give necessary and appropriate treatment and explain
it to the study participants.At the same time, adverse events were followed up until
they returned to normal or the principal investigator determined that no further
follow-up was necessary.In addition, the principal investigator must record all adverse
events in the case report form.
4. Communication with Ethics Committee and superior drug regulatory authorities
Conduct clinical trials in accordance with the content of ethical approval, and timely
communicate with ethics committee and superior drug regulatory authorities when
there are problems encountered in the course of the trial or when the trial plan needs
to be modified.Consent is required to change the test protocol.Communicate when
there is a problem.

5. The entry and management of the internal data analysis plan shall be the
responsibility of the designated data manager.In order to ensure the accuracy of the
data, two data managers should independently make two copies of the input and
proofread.For problems in the case report, the data manager will produce an answer
sheet and send an inquiry to the investigator through the Clinical Ombudsman, who
should answer and return as soon as possible.The data manager will modify, confirm
and enter the data according to the researcher's answers.
Compliance with ethical principles and related regulations
This trial will be conducted in accordance with the research protocol, the
Guidelines for the Ethical Review of Life Sciences and Medical Research Involving
Humans (2023), the Guidelines for the Ethical Review of Biomedical Research
Involving Humans (2016), the WMA Declaration of Helsinki (2013), and the CIOMS
International Ethical Guidelines for Biomedical Research on Humans (2002)Health
institutions conducting investigator-initiated Clinical Research Management
Measures (Trial) and Ethical Principles of GCP research implement all applicable laws
and regulations of the country.Conduct the study only after obtaining written
approval from the Ethics Committee (IRB/IEC) on the protocol, informed consent,
and study participant recruitment materials/processes.The proposed amendments
also require IRB/IEC approval.
Statistical analysis plan
1.Analysis Set
(1) Full analysis Set (FAS) : All randomized study participants who were evaluated
for efficacy at least once were deleted from the analysis set for data that were not
evaluated for efficacy at least once.
(2) Meeting protocol set (PP) : Study participants in FAS who met the inclusion
criteria and did not meet the exclusion criteria, completed the CRF form as planned,
and did not use drugs that might affect the efficacy evaluation during the trial.Safety
Dataset (SS) : Study participants who received at least one treatment after
randomization.
2. Statistical Analysis
(1) The statistical analysis plan will be developed before the end of the trial and
determined before the database is locked.Including statistical description and analysis
methods, all statistical tests were carried out by bilateral test and SPSS22 was used for

statistics.For patient information, if it is a continuous variable and follows normal
distribution, it is described by mean ± standard deviation, and the difference between
groups is compared by T-test.Those who did not follow the normal distribution were
expressed as the median (upper and lower quartile), and the difference between
groups was compared using the non-parametric rank sum test (Mann-WhitneyU
test).For categorical variables such as the incidence of hypoxia, the frequency and rate
(or composition ratio) were expressed, and the difference between groups was
compared by Chi-square test or Fisher exact probability method.
(2) Main indicators:
1) Intraoperative hypoxia was described by frequency (incidence) and Chi-square test
or Fisher analysis was intended to determine whether there was a difference in the
incidence of hypoxia between the two groups. Test P < 0.05 was considered
statistically significant, and confidence interval was 95%.
2) Processing of missing data: Missing data or illogical data delete cases with missing
values or use missing value filling methods (mean interpolation, maximum likelihood
estimation, or multiple interpolation, etc.).
3) It is planned to collect clinical data and CRF tables of all subjects for examination,
data entry and statistical analysis before May 2025.
Description of the new oropharyngeal airway used in the
test
This product is produced and sold by Shanghai Elifu Medical Technology
Co., LTD., and has been officially put into clinical use in March 2023.The product
is named oropharyngeal airway for disposable endoscope, which is composed of
nasal plug, bite, oropharyngeal channel, oxygen supply tube, lanyard and optional
accessories carbon dioxide gas catheter and carbon dioxide collection tube.The
model used in this study is JK (Oropharyngeal airway for endoscope with end-
expiratory carbon dioxide Collection) with L/M/S three specifications, which is
used to prevent airway obstruction caused by backward tongue fall during
endoscopic surgery/examination, establish oropharyngeal airway for patients, and
provide nasal oxygen at the same time.Usage: 1) Put the bite into the patient's
mouth and fix it behind the patient's head with an elastic lashing rope;2) One end
of the oxygen supply tube is connected to the oxygen delivery interface at the bite
of the inlet pharynx vent, and the other end is connected to the center for oxygen
supply and pre-oxygen delivery;3) According to routine clinical procedures, the

patient was implanted into the oropharyngeal channel after anesthesia;4) When the
JK/JK1 type is used, connect the carbon dioxide gas pipe with the carbon dioxide
collection pipe, and connect the carbon dioxide collection pipe connection port to
the carbon dioxide monitoring device;5) Endoscopic operation can be started;6)
Patients were monitored with oxygen inhalation and end-expiratory carbon
dioxide collection during endoscopic surgery or examination.This product should
be operated by professional personnel, and the medical personnel using this
product should be trained in the corresponding technology.
How research results are published
The results of the study will be published in the form of a paper, and 1-2 articles
included in SCI will be published.