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Research Article
Propofol Combined with Fentanyl Is Superior to Propofol
Alone in Sedation Protocols for Painless
Gastrointestinal Endoscopy
Jie Chang
1
and Chun Yang
2
1
Department of Anesthesiology, The Second Hospital of Jiaxing, China
2
Department of Anesthesiology, The Affiliated Hospital of Jiaxing University, China
Correspondence should be addressed to Chun Yang; mail17816519327@163.com
Received 10 March 2021; Revised 26 April 2021; Accepted 29 April 2021; Published 17 May 2021
Academic Editor: Songwen Tan
Copyright © 2021 Jie Chang and Chun Yang. This is an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is
properly cited.
Sufficient propofol or fentanyl doses necessary to prevent the response to skin incision do not necessarily reduce hemodynamic
responses during surgery. The purpose of this study was to characterize the pharmacodynamic interaction between propofol and
fentanyl with respect to the sedative effects and safety during painless gastrointestinal endoscopy. From October 2018 to
October 2020, 200 patients undergoing painless gastrointestinal endoscopy in our department’s outpatient or inpatient clinic
were selected and randomly divided into a control group and an observation group, 100 patients per group. Prior to surgery, the
patients in the two groups were required to be connected to an electrocardiogram monitor and then were instructed to lie on
the left side and receive continuous oxygen infusion of 2-3 L/min with a nasal cannula. The control group was injected with
propofol injection (100 mg/min). The observation group was given fentanyl intravenous injection at a dose of 0.1 μg/kg followed
by propofol injection (100 mg/min). Painless gastrointestinal endoscopy was performed after the patients entered a sleep state
and the eyelash reaction disappeared. Outcome analysis was performed on preoperative and intraoperative hemodynamic
indicators, including heart rate, blood oxygen saturation, dose of propofol, time for endoscopy, recovery time, hospitalization
after recovery, Montreal Cognitive Assessment (MoCA) score, and Mini-Mental State Examination (MMSE) score. The
incidence rate of adverse reactions in the observation group was 6%, which was notably lower than that of the control group
(18%). The total response rate of the observation group was 98%, which was significantly higher than that of the control group
(90%) (P<0:05). The intraoperative heart rate and blood oxygen saturation of the observation group were higher than those of
the control group (P<0:0ss). The patients receiving sedation with propofol plus fentanyl had fewer doses of propofol and
shorter recovery time than those receiving propofol alone (P<0:05). It was also revealed that the patients receiving sedation
with propofol plus fentanyl exhibited more MoCA and MMSE scores than those receiving propofol alone 30 min after sedation
during painless gastrointestinal endoscopy. Taken together, sedation with propofol combined with fentanyl was more effective
and safer than that with propofol alone in painless gastrointestinal endoscopy, which can ensure a wake-up state, stable
breathing cycle, and better gastrointestinal painless procedure.
1. Background
Gastrointestinal endoscopy plays an important role in the
discovery of digestive tract diseases, especially early cancer,
and has been gradually included in the scope of routine phys-
ical examination [1]. The endoscopy is performed to identify
potentially premalignant lesions in the gastrointestinal tract,
sample or resect the area of interest, await histologic results,
and then plan a treatment and/or surveillance strategy [2].
Detection of subtle lesions and decision about whether they
are clinically significant depend on the skills and experience
of endoscopists. For patients undergoing gastrointestinal
endoscopy, most of them still need to rely on the effect of
anesthesia to achieve a stable examination, so as to reduce
the patient’s fear of the examination and make comfortable
medical treatment more extensive and safer [3]. The
Hindawi
Journal of Nanomaterials
Volume 2021, Article ID 9955488, 7 pages
https://doi.org/10.1155/2021/9955488
anesthesia requirements and technical level of painless gas-
trointestinal endoscopy are also constantly updated and
improved [4]. However, because gastrointestinal endoscopy
is an intrusive operation, patients often experience various
degrees of stress, fear, nausea, increased blood pressure, and
pulse speed when undergoing the examination [5]. Some
patients even refuse the examination because of fear, leading
to delays in diagnosis and treatment.
Endoscopic diagnosis and treatment are safe, minimally
invasive, and effective diagnosis and treatment methods
commonly used in gastroenterology clinics. It is currently a
rapidly developing, mature technology and widely used clin-
ical medical technology. However, in the process of endo-
scopic diagnosis and treatment, patients usually have
varying degrees of tension, fear, anxiety, nausea, bloating,
abdominal pain, and other discomforts, which often affect
the examination. In recent years, painless endoscopy is a
good aid to gastrointestinal endoscopy through the applica-
tion of anesthetics [6]. It has the characteristics of being pain-
less and more humane, low missed diagnosis rate, and no
serious complications. It is currently widely used in clinical
practice. However, propofol for injection, which is routinely
used in painless gastrointestinal endoscopy, has no analgesic
effect. When encountering strong painful stimuli, patients
still respond and affect operation [7].
How to obtain a better anesthesia effect, shorten the
awakening time, and improve the comfort of patient exami-
nations requires continuous exploration and research. Pain-
less gastrointestinal endoscopy is a common clinical
method to diagnose and treat digestive system diseases,
which can minimize the suffering of patients [8]. Therefore,
it is favored by patients and physicians. In the process of
painless gastrointestinal endoscopy, it is often necessary to
use propofol for anesthesia. It has a good anesthesia and sed-
ative effect, and it has fast onset and can make the patient
wake up quickly, but it will also affect the patient’s respiratory
system and heart. The blood vessels have a certain inhibitory
effect, and no better analgesic effect can be achieved. In this
study, we recruited 200 patients undergoing painless gastro-
intestinal endoscopy to characterize the pharmacodynamic
interaction between propofol and fentanyl with respect to
the sedative effects and safety during painless gastrointestinal
endoscopy.
2. Materials and Methods
2.1. Ethical Statement. The MoCA and MMSE scales were
performed with the approval of the Ethics Committee of
the Affiliated Hospital of Jiaxing University.
2.2. Inclusion and Exclusion Criteria. The study subjects in
this study should meet the following inclusion and exclusion
criteria. Inclusion criteria were as follows: (1) requirement
for gastrointestinal endoscopy; (2) I-II grades according to
the American Society of Anesthesiologists (ASA) Classifica-
tion System which was developed to offer clinicians a simple
categorization of a patient’s physiological status that can be
helpful in predicting operative risk [9]; (3) education level
reaching primary school or above; (4) age ranging from 18
to 70 years old; and (5) providing informed content. Exclu-
sion criteria were as follows: (1) those with contraindications
to endoscopy; (2) those allergic to the medication used in this
observation; (3) those with severe obstructive pulmonary dis-
ease and severe snoring; (4) those with cognitive impair-
ments or neurological disorders; and (5) those with severe
heart, liver, and kidney dysfunction.
2.3. Participants. From October 2018 to October 2020, 200
patients who underwent painless gastrointestinal endoscopy
in our department’s outpatient or inpatient clinic were
selected as study subjects who meet the inclusion and exclu-
sion criteria. These 200 patients were randomly arranged into
the control group and observation group, 100 per group. The
control group consisted of 48 males and 52 females, aged 22
to 70 years old, with an average age of 42:46 ± 5:63 years and
an average weight of 66:5±8:2kg. The patients in the control
group underwent painless gastrointestinal endoscopy for the
following reasons: chronic inflammation of the digestive tract
(n=30), physical examination (n=27), esophageal reflux
(n=12), gastric polyps (n=9), intestinal polyps (n=10),
constipation (n=9), and lower abdominal pain (n=3); gas-
troscopy was performed in 54 cases and colonoscopy in 46
cases. The observation group consisted of 45 males and 55
females, aged 22 to 71 years old, with an average age of
46:22 ± 5:19 years and an average weight of 68:3±7:5kg.
The patients in the observation group underwent painless
gastrointestinal endoscopy for the following reasons: physical
examination (n=28), chronic inflammation of the digestive
tract (n=26), gastric polyps (n=12), gastric ulcer (n=12),
intestinal polyps (n=12), constipation (n=6), and lower
abdominal pain (n=4); gastroscopy was performed in 56
cases and colonoscopy in 44 cases. The two groups exhibited
no significant differences in sex, age, weight, and disease
(P>0:05), and they were comparable.
2.4. Sedation Protocols. Eight hours before painless gastroin-
testinal endoscopy, the patients in the two groups were
required to abstain from food and drink, be given an indwell-
ing needle, have the venous channel open by intravenous
infusion of normal saline, and be connected to the ECG mon-
itor to observe and record the patient’s blood pressure, heart
rate, and oxygen saturation After confirming that they are
within the normal range, the patient is instructed to lie on
the left side and given continuous oxygen infusion of 2-
3 L/min with a nasal cannula. The control group was injected
slowly with propofol injection (Guangdong Jiabo Pharma-
ceutical Co., Ltd., National Medicine Zhunzi H20051842),
and the injection speed was 100 mg/min; the observation
group was given fentanyl intravenously at a dose of 0.1 μg/kg
and then injected with propofol, and the injection speed is
100 mg/min. Painless gastrointestinal endoscopy can be per-
formed after the patient enters a sleep state and the eyelash
reaction disappears. Both groups used our Olympus 260
series electronic gastrointestinal endoscopy for inspection
operations. Gastroscopy can usually be done with a single
dose. Propofol can be added to colonoscopy according to
the situation. During the examination, blood pressure, heart
rate, oxygen saturation, and patient response are closely
2 Journal of Nanomaterials
monitored, and the dosage of propofol and the patients's
wake-up time after anesthesia are recorded. Those with
abnormal blood pressure and heart rate can be treated symp-
tomatically. Record the patient’s blood pressure, heart rate,
and blood oxygen saturation before and after the
examination.
2.5. Evaluation of Patient Outcomes. The sedative effects of
anesthetic drugs were evaluated as follows: 80-100 points
indicate excellent response (namely, the patient has no
adverse reactions and the painless gastrointestinal surgery is
successfully finished); 80-100 points indicate good response
(namely, the patient experiences mild adverse reactions and
the painless gastrointestinal surgery is basically finished);
and less than 60 points indicate poor response (namely, the
patient experiences serious adverse reactions and the painless
gastrointestinal surgery is difficult to finish). Total response
rate = ðexcellent + good responseÞ/total number of cases ×
100%. Adverse reactions following painless gastrointestinal
surgery include intraoperative respiratory depression, vomit-
ing, and dizziness. The hemodynamic parameters of painless
gastrointestinal surgery include heart rate and blood oxygen
saturation.
2.6. Mini-Mental State Examination (MMSE) Scale. In clini-
cal and research settings, the MMSE is the most widely used
instrument for the screening of cognitive impairment world-
wide, which correlates well with more time-consuming Intel-
ligence Quotient (IQ) tests, but it will not easily pick up
cognitive problems caused by focal brain lesions. Scale items
involve orientation (What is the time, date, day, month, and
year? What is the name of this ward, hospital, district, town,
and country?), registration (name three objects only once;
repeat the objects until the patient can repeat them accu-
rately), attention and calculation (ask the patient to subtract
7 from 100 and then 7 from the result four more times), recall
(ask the patient to repeat the names of the three objects learnt
in the registration test), and language (each of two simple
objects named; an accurate repetition of the phrase; give a
3-stage command; write “Close your eyes”on a blank piece
of paper and ask the patient to follow the written command;
ask the patient to write a sentence. Score 1 point if the sen-
tence is sensible and contains a noun and a verb; draw a pair
of intersecting pentagons with each side approximately 1
inch long). Total maximum scores are 30 points. A score of
17 or less for illiteracy, 20 or less for primary school, and
24 or less for senior high school and above will pick up about
90% of patients with cognitive impairments, with about 10%
false positives. If the postoperative score is 2 points lower
than the preoperative score, it is considered that the cognitive
function of patients was decreased.
2.7. Montreal Cognitive Assessment (MoCA) Scale. The
MoCA is a 30-point scale containing the following subitems:
visuospatial/executive functions, naming, memory, attention,
language-sentence repetition, and language-verbal fluency.
Visuospatial/executive functions: shapes were changed
from circle to triangle, and Roman alphabets were replaced
in the trail making test part B as there was no substitute for
Roman alphabets in Chinese. The number of steps required
for the completion of the task was retained.
Naming: the picture of a rhinoceros was replaced with an
elephant to reflect local familiarity.
Memory: the word “velvet”was replaced with “silk”and
“daisy”was replaced with “rose”to reflect local familiarity.
Attention: Arabic numerals were used instead of Roman
alphabets for the reasons given above; the numbers and posi-
tions of responses were retained
Language-sentence repetition: the name used in the Chi-
nese version was changed to a more common Chinese name
to reflect local familiarity.
Language-verbal fluency: phonemic letter fluency was
replaced by animal fluency as there is no letter-equivalent lin-
guistic unit in Chinese.
A score of 26 or more indicates normal cognitive
function.
2.8. Statistical Methods. The data was processed by using
SPSS 21.0 statistical software. The measurement data is
expressed as mean ± standard deviation, and the t-test is per-
formed. The count data is expressed as cases (percentage),
and the chi-square test is performed. The difference was sta-
tistically significant (P<0:05).
3. Results
3.1. Sedation with Propofol plus Fentanyl Inhibited the
Incidence of Intraoperative Respiratory Depression during
Painless Gastrointestinal Endoscopy. The incidence of
adverse reactions was analyzed in sedation protocols of pro-
pofol with or without fentanyl for painless gastrointestinal
endoscopy. The patients experienced adverse reactions
including intraoperative respiratory depression, vomiting,
and dizziness. There were 5 cases of intraoperative respira-
tory depression, 5 cases of vomiting, and 5 cases of dizziness
in the observation group. The control group had 13 cases of
intraoperative respiratory depression, 6 cases of vomiting,
and 6 cases of dizziness. The two groups showed significant
difference in the incidence of intraoperative respiratory
depression (Figure 1, P=0:0485). However, no significant
difference was detected in the total incidence of adverse reac-
tions (P=0:077).
3.2. Propofol plus Fentanyl Conferred Better Sedative Effects
than Propofol Alone for Painless Gastrointestinal Endoscopy.
In order to compare the sedative effects of protocols of pro-
pofol with or without fentanyl during painless gastrointesti-
nal endoscopy, each patient was evaluated as having
excellent response, good response, and poor response. The
observation group had 88 patients with excellent response,
10 with good response, and 2 with poor response. The con-
trol group had 80 patients with excellent response, 10 with
good response, and 10 with poor response. The total response
rate of the observation group was 98%, which was signifi-
cantly higher than that of the control group (90%)
(Z=2:382,P<0:05, Table 1).
3.3. Sedation with Propofol plus Fentanyl Maintained
Hemodynamic Status during Painless Gastrointestinal
3Journal of Nanomaterials
Endoscopy. Subsequent analysis was performed to examine
the influence of protocols of propofol with or without fenta-
nyl on the hemodynamic status of the patients undergoing
painless gastrointestinal endoscopy. The heart rate and blood
oxygen saturation were evaluated to reflect patient hemody-
namic status. There was no significant difference in the heart
rate and blood oxygen saturation between the two groups
before painless gastrointestinal endoscopy. During the gas-
trointestinal endoscopy, the heart rate and blood oxygen sat-
uration in the observation group were higher than those in
the control group (P<0:05, Table 2).
3.4. Sedation with Propofol plus Fentanyl Promoted Patient
Recovery after Painless Gastrointestinal Endoscopy. Each
patient was evaluated for dose of propofol, time for endos-
copy, recovery time, and hospitalization after recovery after
painless gastrointestinal endoscopy. As shown in Table 3,
the patients receiving sedation with propofol plus fentanyl
had fewer doses of propofol and shorter recovery time than
those receiving propofol alone (P<0:05), indicating that
sedation with propofol plus fentanyl promoted patient recov-
ery after painless gastrointestinal endoscopy. However, no
remarkable difference was found with regard to time for
endoscopy and hospitalization after recovery (P>0:05).
3.5. MoCA and MMSE Scores of Patients Receiving Sedation
with Propofol plus Fentanyl or Propofol Alone during
Painless Gastrointestinal Endoscopy. The potential for indi-
viduals to develop cognitive impairment as a consequence
of major surgery with anesthesia has been increasingly recog-
nized. We used MoCA and MMSE scales to reflect the cogni-
tive function of patients receiving sedation with propofol
plus fentanyl or propofol alone before and 30 min and
60 min after sedation during painless gastrointestinal endos-
copy. The MoCA and MMSE scores between the observation
group and the control group before and 60 min after gastro-
intestinal endoscopy were not statistically different (P>0:05
). The patients receiving sedation with propofol plus fentanyl
exhibited more MoCA and MMSE scores than those receiv-
ing propofol alone 30 min after sedation during painless gas-
trointestinal endoscopy (P<0:05, Figure 2).
4. Discussion
Gastrointestinal diseases are one of the more common dis-
eases in clinical medicine. With the continuous progress
and development of social economy and culture, people’s
material lifestyles are changing day by day, and the incidence
of gastrointestinal diseases has increased significantly. At
present, the main treatment of gastrointestinal diseases in
clinical medicine is painless gastrointestinal endoscopy
[10]. Through gastrointestinal endoscopy, the patient’s spe-
cific gastrointestinal disease can be clarified and the patient
can be treated. Propofol is the commonly used anesthetic
before painless gastrointestinal surgery [11]. Due to many
factors, its anesthesia effect is not very obvious, and it is easy
30
Z = 1.972
P < 0.048
Observation group
Control group
20
e incidence of adverse reactions
10
0
Intraoperative
respiratory
depression
Vomiting Dizziness Total
Figure 1: The incidence of adverse reactions after painless gastrointestinal endoscopy in the observation and control groups.
Table 1: Sedative effects of propofol plus fentanyl or propofol alone during painless gastrointestinal endoscopy.
Excellent response Good response Poor response Total response rate
Observation group (n= 100)88 10 2 98
Control group (n= 100)80 1010 90
Z—— 2.382
P—— 0.017
4 Journal of Nanomaterials
to cause adverse reactions in patients [12]. Many scholars in
the medical field believe that propofol combined with low-
dose fentanyl can not only have a good anesthesia effect but
also reduce the incidence of adverse reactions in patients
[13]. Therefore, in order to clarify the effect of the combina-
tion of propofol and fentanyl on painless gastrointestinal sur-
gery, this study launched a study on the application of
propofol and fentanyl. The results of this study showed that
the two groups showed significant difference in the incidence
of intraoperative respiratory depression. However, no signif-
icant difference was detected in total incidence of adverse
reactions. In terms of response rate and preoperative and
intraoperative heart rate and blood oxygen saturation and
intraoperative hemodynamic comparison, the observation
group was better than the control group. The reason is that
the propofol drug in the control group is an anesthesia-
inducing drug, and its chemical name is diisopropylphenol.
By activating the GABA receptor-chloride ion complex, it
can inhibit the central nervous system and finally achieve
sedation and hypnosis [14]. Based on the propofol drug, the
observation group implemented fentanyl citrate. This drug
is an analgesic with a molecular structure similar to mor-
phine. It is combined with propofol as an anesthetic. Fenta-
nyl is a synthetically powerful horse mouth analgesic. It is
mainly absorbed through the gastrointestinal tract and fully
binds to the human body proteins. It not only has a small
impact on the cardiovascular function of patients but also
can achieve analgesia [15]. The dosage of propofol combined
with fentanyl was significantly reduced, and the patient’s
consciousness recovered faster after the operation was
Table 2: Preoperative and intraoperative heart rate and blood oxygen saturation of patients receiving sedation with propofol plus fentanyl or
propofol alone during painless gastrointestinal endoscopy.
Heart rate (times/min) Blood oxygen saturation (%)
Preoperative Intraoperative Preoperative Intraoperative
Observation group (n= 100)72:36 ± 1:31 67:98 ± 1:22 98:65 ± 1:75 96:12 ± 1:26
Control group (n= 100)72:56 ± 1:37 63:26 ± 1:25 98:36 ± 1:69 94:26 ± 1:36
t1.055 27.023 1.192 10.031
P0.293 0.0001 0.235 0.0001
Table 3: Dose of propofol, time for endoscopy, recovery time, and hospitalization after recovery of patients receiving sedation with propofol
plus fentanyl or propofol alone during painless gastrointestinal endoscopy.
Group Dose of propofol (mg) Time for endoscopy
(min)
Recovery time
(min)
Hospitalization after recovery
(min)
Observation group (n= 100
)114:89 ± 7:34 15:01 ± 6:47 5:67 ± 1:48 20:97 ± 5:32
Control group (n= 100)129:47 ± 8:14 16:22 ± 7:18 7:73 ± 1:56 22:17 ± 7:49
t13.300 1.252 9.580 1.306
P<0.0001 0.212 <0.0001 0.193
Observation group
Control group
t = 12.470
P < 0.001
40
30
20
MMSE scores
10
0
Before
anesthesia
30 min aer
anesthesia
60 min aer
anesthesia
40 t = 8.932
P < 0.001
30
20
MoCA scores
10
0
Before
anesthesia
30 min aer
anesthesia
60 min aer
anesthesia
Figure 2: MoCA and MMSE scores of patients receiving sedation with propofol plus fentanyl or propofol alone during painless
gastrointestinal endoscopy.
5Journal of Nanomaterials
extubated, and the eye opening time was shorter. However,
with propofol alone, the dosage is large, the breathing is easily
inhibited, the recovery of consciousness after extubation after
the operation is slow, and the recovery from opening eyes is
slow. It can be seen that the effect of propofol combined with
small dose of fentanyl is better [16].
Although gastrointestinal endoscopy does not take a long
time, it can also cause a certain degree of pain to the patient
during the examination. Therefore, anesthesia is usually
required. The ideal anesthesia state is to ensure the stability
of the patient’s hemodynamic changes during the detection
process; at the same time, it can be quickly induced by anes-
thesia, and the patient can be quickly awakened after the
operation [17]. At present, propofol is usually used in gastro-
intestinal endoscopy. Although it has good anesthesia and
sedation, it can induce anesthesia quickly and can make the
patient wake up quickly after surgery, but it also affects
patients. The respiratory system and cardiovascular system
have inhibitory effects [18], as shown by our results. Fentanyl
is a synthetic opioid receptor agonist [19]. Compared with
propofol, it has a shorter induction time for anesthesia and
does not have much impact on the cardiovascular system.
Remifentanil is an opioid receptor agonist with a short half-
life and will not affect liver and kidney function. The results
of this study confirm that the application of a small amount
of remifentanil combined with a small dose of propofol in a
painless gastrointestinal endoscopy can achieve a very ideal
anesthesia effect and can ensure that the patient is in a wake-
ful state and is stable. The breathing cycle of the painless gas-
trointestinal endoscopy is significantly improved, and its
anesthesia effect is far superior to that of the conventional
dose of fentanyl combined with propofol anesthesia.
In this study, the two groups showed significant differ-
ence in the incidence of intraoperative respiratory depres-
sion. However, no significant difference was detected in the
total incidence of adverse reactions. The total response rate
of the observation group was 98%, which was significantly
higher than that of the control group (90%), and the differ-
ence was statistically significant. There was no significant dif-
ference in heart rate, blood oxygen saturation, and
hemodynamics between the two groups before operation.
The intraoperative heart rate and blood oxygen saturation
of the observation group were higher than those of the con-
trol group, and the difference was statistically significant.
The MoCA and MMSE scores of the two groups before and
after anesthesia were not statistically different. The MoCA
and MMSE scores of the observation group were higher than
those of the control group at 30 minutes after anesthesia, and
there was a statistical difference.
In summary, propofol plus fentanyl in painless gastroin-
testinal endoscopy can achieve a very ideal sedative effect,
ensure that the patient is in a wakeful state, and ensure the
patient’s breathing cycle is stable, so that the safety of gastro-
intestinal endoscopy has been significantly improved. Propo-
fol combined with low-dose fentanyl is safer, can reduce the
incidence of adverse reactions in patients, and has certain
clinical application value. Nevertheless, different doses of
fentanyl combined with propofol in sedation protocols for
painless gastrointestinal endoscopy will be explored in fur-
ther study.
Data Availability
The data used to support the findings of this study are
included within the article.
Conflicts of Interest
The authors declare that they have no conflicts of interest.
References
[1] P. Valdastri, M. Simi, and R. J. Webster 3rd, “Advanced tech-
nologies for gastrointestinal endoscopy,”Annual Review of
Biomedical Engineering, vol. 14, no. 1, pp. 397–429, 2012.
[2] A. M. Thaker and V. R. Muthusamy, “Advanced imaging tech-
niques in gastrointestinal endoscopy,”Journal of Laparoendo-
scopic & Advanced Surgical Techniques Part A, vol. 27, no. 3,
pp. 234–241, 2017.
[3] A. S. o. P. Committee, D. S. Early, J. R. Lightdale et al., “Guide-
lines for sedation and anesthesia in GI endoscopy,”Gastroin-
testinal Endoscopy, vol. 87, no. 2, pp. 327–337, 2018.
[4] C. J. Rees, S. Koo, and K. W. Oppong, “Future directions in
therapeutic gastrointestinal endoscopy,”The Lancet Gastroen-
terology & Hepatology, vol. 3, no. 10, pp. 663-664, 2018.
[5] M. R. Borgaonkar, L. Hookey, R. Hollingworth et al., “Indica-
tors of safety compromise in gastrointestinal endoscopy,”
Canadian Journal of Gastroenterology, vol. 26, no. 2, pp. 71–
78, 2012.
[6] O. S. Lin, “Sedation for routine gastrointestinal endoscopic
procedures: a review on efficacy, safety, efficiency, cost and sat-
isfaction,”Intestinal Research, vol. 15, no. 4, pp. 456–466,
2017.
[7] T. Nishizawa and H. Suzuki, “Propofol for gastrointestinal
endoscopy,”United European Gastroenterology Journal,
vol. 6, no. 6, pp. 801–805, 2018.
[8] L. Zhang, Y. Bao, and D. Shi, “Comparing the pain of propofol
via different combinations of fentanyl, sufentanil or remifenta-
nil in gastrointestinal endoscopy,”Acta Cirúrgica Brasileira,
vol. 29, no. 10, pp. 675–680, 2014.
[9] D. J. Doyle, A. Goyal, P. Bansal, and E. H. Garmon, American
Society of Anesthesiologists Classification, StatPearls, Treasure
Island, FL, USA, 2021.
[10] J. J. McGoran, M. E. McAlindon, P. G. Iyer et al., “Miniature
gastrointestinal endoscopy: now and the future,”World Jour-
nal of Gastroenterology, vol. 25, no. 30, pp. 4051–4060, 2019.
[11] D. Stogiannou, A. Protopapas, A. Protopapas, and
K. Tziomalos, “Is propofol the optimal sedative in gastrointes-
tinal endoscopy?,”Acta Gastroenterologica Belgica, vol. 81,
no. 4, pp. 520–524, 2018.
[12] R. Zhang, Q. Lu, and Y. Wu, “The comparison of midazolam
and propofol in gastrointestinal endoscopy: a systematic
review and meta-analysis,”Surgical Laparoscopy, Endoscopy
& Percutaneous Techniques, vol. 28, no. 3, pp. 153–158, 2018.
[13] A. Amini, A. Arhami Dolatabadi, H. Kariman et al., “Low-dose
fentanyl, propofol, midazolam, ketamine and lidocaine combi-
nation vs. regular dose propofol and fentanyl combination for
deep sedation induction; a randomized clinical trial,”Emer-
gency, vol. 6, no. 1, article e57, 2018.
6 Journal of Nanomaterials
[14] M. Hara, Y. Kai, and Y. Ikemoto, “Propofol activates GABAA
receptor-chloride ionophore complex in dissociated hippo-
campal pyramidal neurons of the rat,”Anesthesiology,
vol. 79, no. 4, pp. 781–788, 1993.
[15] F. Zhang, J. Tong, W. Qing, Z. Hu, J. Hu, and Q. Liao, “MDR1
genotypes and haplotypes are closely associated with postoper-
ative fentanyl consumption in patients undergoing radical gas-
trectomy,”Journal of Nanomaterials, vol. 2021, Article ID
5587399, 8 pages, 2021.
[16] H. S. Bakhamees, A. Mercan, and Y. M. El-Halafawy, “Combi-
nation effect of low dose fentanyl and propofol on emergence
agitation in children following sevoflurane anesthesia,”Saudi
Medical Journal, vol. 30, no. 4, pp. 500–503, 2009.
[17] H. Hosseinzadeh, S. E. Golzari, E. Torabi, and M. Dehdilani,
“Hemodynamic changes following anesthesia induction and
LMA insertion with propofol, etomidate, and propofol + eto-
midate,”Journal of Cardiovascular and Thoracic Research,
vol. 5, no. 3, pp. 109–112, 2013.
[18] J. E. Mandel, G. R. Lichtenstein, D. C. Metz, G. G. Ginsberg,
and M. L. Kochman, “A prospective, randomized, comparative
trial evaluating respiratory depression during patient-
controlled versus anesthesiologist-administered propofol-
remifentanil sedation for elective colonoscopy,”Gastrointesti-
nal Endoscopy, vol. 72, no. 1, pp. 112–117, 2010.
[19] D. Lu, L. Jiang, C. Dai, K. Yan, and J. Gao, “Fentanyl exerts an
antitumor effect on papillary thyroid cancer by regulating the
miR-204/KLF5 axis,”Journal of Nanomaterials, vol. 2021,
Article ID 5563901, 8 pages, 2021.
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