Abstract
Background
Gastric cancer is a type of malignant gastrointestinal tumor that poses a serious threat to human life and ranks as the second leading cause of cancer-related mortality worldwide. Although cardia-related diseases are rarely reported in the literature on gastrointestinal disorders, cardia lesions are not uncommon in clinical practice. The development of esophageal cancer may be associated with risk factors for esophageal adenocarcinoma, such as reflux esophagitis, high-fat diet, advanced age, and obesity. During gastroscopy, it is important to note that inadequate visualization of the esophagus may result from various factors, which can affect the diagnosis of esophageal lesions and lead to misdiagnosis or missed diagnoses. Currently, intravenous sedation using a combination of fentanyl and propofol is routinely administered during gastrointestinal endoscopy. The use of propofol in gastroscopy has been shown to improve procedural quality, enhance patient tolerance, and increase the accuracy of endoscopic diagnosis. However, the differences in esophageal exposure between moderate and deep sedation still require further clinical validation.
Methods
This study was a single-center retrospective clinical study. One hundred and twenty elderly overweight patients who underwent sedation for upper gastrointestinal endoscopy at our Gastrointestinal Endoscopy Center from May 2020 to August 2023 were retrospectively collected and divided into a moderate sedation group (Group A) and a deep sedation group (Group B) according to the anesthesia method. Primary outcome index: compare the sedation success rate and cardia exposure degree between the two groups. Secondary outcome indicators: compare the incidence of hypoxia during sedation between the two groups. Comparison of sedation recovery time, pain [visual analog scale (VAS)] and patient satisfaction.
Results
A total of 120 patients aged 60–75 years with body mass index ≧ 25 kg/m2 were enrolled. The general data of the patients in the two groups were comparable (P > 0.05).The sedation success rate was comparable in Groups A and B (94.83% vs. 96.78%, P = 0.594).The degrees of cardia exposure in group A and group B were compared. The degrees of cardia exposure in Group A with scores of 1, 2, 3, and 4 were 12 cases (20.69%), 13 cases (22.41%), 19 cases (32.76%), and 14 cases (24.14%), respectively. The degrees of cardia exposure in group B were 21 cases (33.87%), 19 cases (30.65%), 18 cases (29.03%), and 4 cases (6.45%), respectively. Compared with group B, group A had a higher degree of cardia exposure, and the difference was statistically significant (p = 0.029). The total perioperative adverse reactions were relatively lower in group A compared with group B, and the difference was statistically significant (P = 0.049).The incidence of hypoxia (2%vs11%) and sedation recovery time (10.08 ± 2.18vs.15.38 ± 3.25) were significantly smaller in group A than in group B, and the differences were statistically significant (P < 0.05).The satisfaction with endoscopy was higher in both groups ( 98.28%vs.96.78%, P = 1.000), the difference was not statistically significant.The exposure of the cardia during gastroscopy was not significantly associated with patient gender, comorbidities such as diabetes, hypertension, or chronic obstructive pulmonary disease(COPD), or gastric or bile reflux, but was significantly associated with the depth of anesthesia (P < 0.05).
Conclusion
Both moderate and deep sedation are applicable for upper gastrointestinal endoscopy in elderly overweight patients. However, moderate sedation is more suitable than deep sedation for those with unstable cardiopulmonary function. Compared with deep sedation, moderate sedation provides better cardia exposure, a lower incidence of hypoxia, faster recovery time, improved safety, and comparable patient satisfaction, making it worthy of clinical promotion.
Supplementary Information
The online version contains supplementary material available at 10.1186/s12871-025-03387-2.
Keywords: Moderate sedation, Elderly, Overweight, Upper gastrointestinal endoscopy, Cardia exposure, Deep sedation, Sufentanil, Propofol
In recent years, the incidence of gastric cardia cancer has shown a significant upward trend globally [1, 2]. The degree of cardia exposure is of great importance for the detection of early cancer at the gastroesophageal junction during gastroscopy, particularly as an essential prerequisite for procedures such as early cancer screening, precise biopsy, and endoscopic treatment.
Advanced age and overweight are two significant factors influencing the degree of cardia exposure [3, 4]. The cardia exposure is often suboptimal in elderly patients with concurrent overweight. With aging, factors such as reduced lower esophageal sphincter tone, weakened crural diaphragm function, and physiological kyphosis collectively contribute to anatomical changes at the esophagogastric junction [5], increasing the difficulty of exposure. Meanwhile, overweight or obese patients experience elevated intra-abdominal pressure due to increased visceral fat and dysfunction of the lower esophageal sphincter, which further causes cephalad displacement of the esophagogastric junction and may be accompanied by a large hiatal hernia [6, 7]. These physiological and anatomical alterations not only predispose these patients to a higher risk of cardia pathology but also pose significant challenges for achieving adequate exposure of the cardia and gastroesophageal junction.
Gastrointestinal endoscopy can be performed under moderate or deep sedation [8, 9]. Previous studies have indicated that deep sedation may impair the exposure of the cardia [10]. However, there remains a lack of in-depth and dedicated research on the effect of moderate sedation on the exposure quality of the gastric antrum and cardia—particularly among specific populations such as elderly overweight patients, who are at high risk of inadequate cardia exposure. Most existing studies have focused on the safety, efficiency, or patient satisfaction related to sedation itself, while its impact on procedural visual field quality—especially potential benefits or risks in patients with difficult cardia exposure—has not been sufficiently explored.
Therefore, this study aims to investigate the impact of different sedation depths on the degree of cardia exposure during upper gastrointestinal endoscopy in elderly overweight patients and to compare the incidence of procedure-related adverse reactions, thereby providing an evidence-based foundation for optimizing sedation strategies in this population.
Materials and methods
General information
Ethics approval and consent to participate
This study was performed in accordance with the ethical principles of the Declaration of Helsinki. This study was approved by the Ethics Committee of the Affiliated Hospital of Qingdao University (Approval No. QYFYWZLL27303). This is a retrospective study and individual informed consent to participate for this retrospective analysis with routine clinical data was waived by the Ethics Committee of the Affiliated Hospital of Qingdao University. We retrospectively collected the electronic medical records of 120 overweight elderly patients who underwent painless gastroscopy at the Digestive Endoscopy Center of our hospital between May 2020 and August 2023.
The inclusion criteria for patients were as follows: (1) underwent painless gastroscopy with either moderate or deep sedation; (2) were between 60 and 75 years old; (3) had a body mass index (BMI) ≥ 25 kg/m²; (4) were eligible for anesthesia and gastroscopy.The exclusion criteria were as follows: (1) did not undergo painless gastroscopy or underwent only mild sedation; (2) were scheduled for endoscopic retrograde cholangiopancreatography, enteroscopy, or procedures requiring planned tracheal intubation; (3) had incomplete medical records.
The patients were divided into Group A (58 patients, moderate sedation) and Group B (62 patients, deep sedation) based on the anesthesia method used. The general characteristics between the two groups were similar (P >0.05, Table 1).
Table 1.
Comparison of the general characteristics between the two groups
| Group | A | B | χ2/t/Z | P |
|---|---|---|---|---|
| Number of Cases | 58 | 62 | – | – |
| Male: Female | 21:37 | 19:43 | 0.417 | 0.518 |
| Age/Years | 62.54 ± 7.33 | 63.15 ±8.22 | 0.274 | 0.785 |
| BMI/kg/m2 | 29.46 ±1.78 | 30.12 ±2.14 | −1.84 | 0.068 |
| ASA physical status Classification/Cases | 0.168 | 0.681 | ||
| I | 24(41.38) | 28(45.16) | ||
| II | 30(48.39) | 31(50.0) | ||
| III | 4(6.90) | 3(4.84) | ||
| Occupation | 0.099 | 0.753 | ||
| Mainly Mental Labor | 39(67.24) | 19(30.65) | ||
| Mainly Physical Labor | 40(68.97) | 22(35.48) | ||
| Complications | ||||
| diabetes mellitus | 22(37.93) | 24(38.71) | 0.010 | 0.920 |
| hypertension | 18(31.03) | 20(32.26) | 0.002 | 0.958 |
| COPD | 17(29.31) | 19(30.65) | 0.001 | 0.968 |
Methods
Our department has established detailed standards and procedures for moderate and deep sedation based on the Expert Consensus on Sedation and Anesthesia in Digestive Endoscopy in China. The moderate sedation gastroscopy procedure is as follows: Before the examination, all patients must fast. Prior to the procedure, peripheral venous access is established. The patient rests in a seated position in the preparation area for 10–30 minutes. An anesthesia risk assessment is then conducted. Based on this assessment, pre-anesthesia education is provided, which combines face-to-face instruction from medical staff and video demonstrations to explain the procedure and alleviate patient anxiety. All patients orally administer lidocaine gel 10 minutes before the examination for topical pharyngeal anesthesia. During the procedure, sedation for both the moderate and deep sedation groups is administered by a trained anesthesiologist. All gastrointestinal endoscopy examinations are performed by one of three experienced attending physicians at the Endoscopy Center, all of whom have equivalent training and experience. All three attending physicians had previously completed 500 gastrointestinal endoscopy examinations procedures as recommended before study enrollment. The cardia is defined as he part of the stomach that lies around the orifice of the tubular esophagus, and which corresponds to the point at which the tubular esophagus joins the saccular stomach [11–13]. Before the examination, the patient assumed a left lateral position. All patients were given Ondansetron injection (8 mg) to prevent vomiting before sedation. A Mindray monitor was used to monitor their heart rate, Peripheral capillary oxygen saturation (SpO2), and blood pressure. The patient was supplied oxygen through a nasal cannula at a flow rate of 3–5 L/min for 3 min.
The sedation level was assessed and monitored using the Modified Observer’s Assessment of Alertness/Sedation (MOAA/S) scale (Table 2), which ranges from 1 point (general anesthesia) to 5 points (fully awake). Moderate sedation was defined as a score of 3 points on the MOAA/S scale, and deep sedation was defined as a score of 1 point. In the moderate sedation group, the anesthesia records indicated that all patients received an initial dose of 10 μg sufentanil, followed three minutes later by an intravenous injection of 10–70 mg of propofol (administered as a slow IV push over 30 seconds). Throughout the endoscopic procedure, the anesthesiologists assessed the sedation level using the MOAA/S scale every 30 seconds from 1 to 3 minutes, and then every minute thereafter, until the patient was alert (defined as three consecutive MOAA/S scores of 5 points [14]). Gastrointestinal endoscopy began when the patient's MOAA/S score reached 3 points [15]. For the maintenance of sedation, adequate sedation was predefined as a MOAA/S score of 3 in all study groups. The total number of propofol boluses was limited to 5 doses within any 15-minute window. If 5 doses (including the initial bolus) within any 15-minute window were insufficient to obtain or maintain the target MOAA/S score [16], [additional protocol-specified interventions were implemented].After entering the esophagus, if the gastric cardia was not fully exposed, the patient was generally prompted to take a deep breath via a loud call. Images of the gastric cardia were then collected, and their heart rate, blood pressure, and oxygen saturation were continuously monitored, with appropriate measures taken for any complication. Any drop in oxygen saturation during the examination was recorded. If the mean arterial pressure (MAP) dropped by more than 30% of the baseline value, 6 mg of ephedrine was administered; if the heart rate (HR) fell below 50 beats per minute, 0.5 mg of atropine was administered. If the SpO2 dropped below 75%, the oxygen flow rate was increased, and if necessary, mask pressure-assisted ventilation was provided. The total propofol dose (mg) administered during the gastroscopy procedure was recorded.
Table 2.
Description of modified observer’s assessment of Alertness/sedation scores
| Score | Description |
|---|---|
| 5 | Responds readily to name spoken in normal tone |
| 4 | Lethargic response to name spoken in normal tone |
| 3 | Responds only after name is called loudly and/or repeatedly |
| 2 | Responds only after mild prodding or shaking |
| 1 | Responds only after painful trapezius squeeze |
| 0 | No response after painful trapezius squeeze |
Deep sedation gastroscopy procedure
Sufentanil combined with propofol was administered for deep sedation. The specific steps were as follows: intravenous injection of 2 µg of sufentanil, followed by an intravenous injection of propofol (1–1.5 mg/kg) 2 min later. Once the patient was unresponsive to verbal cues, had relaxed muscles, stable breathing, and no eyelash reflex(MOAA/S scores of 1point), gastroscopy was performed. Anesthesia during the procedure was managed by a professional anesthesiologist, and a MOAA/S score of 1was maintained. For the maintenance phase of sedation, adequate sedation was predefined as a MOAA/S score of 1 in all study arms. The overall number of propofol doses was limited to 5 doses in any 15 min window. If 5 doses (including the initial bolus) within any 15-minute window were not sufficient to obtain or MOAA/S, Modified Observer’s Assessment of Alertness/Sedation. The total propofol dose (mg) administered during the gastroscopy procedure was recorded.
If treatment failure was determined in any study group, propofol was the only sedative medication (rescue medication) permitted for completion of the gastroscopy. Once a patient was designated a treatment failure, rescue propofol was dosed at the anesthesiologists’ discretion.
Indicator testing
Degree of gastric cardia exposure [10, 15]
The degree of exposure of the dentate line was scored based on its completeness. The gastric cardia is the area of the stomach closest to the esophagus, starting at the esophagogastric junction. According to the characteristics of the Chinese population, it is the area where the esophageal squamous epithelium meets the gastric columnar epithelium, specifically the junction and the 2 cm area below it. The scoring is as follows: 1 point: the dentate line of the gastric cardia is completely unexposed; 2 points: completely unexposed to half-exposed; 3 points: half-exposed to fully exposed; 4 points: fully exposed. Figure 1 illustrates the scoring system.
Fig. 1.
Scoring of the degree of gastric cardia exposure. A The dentate line of the gastric cardia is completely unexposed: 1 point. B Completely unexposed to half-exposed: 2 points. C Half-exposed to fully exposed: 3 points. D Fully exposed: 4 points
Sedation recovery time and sedation success rate
Sedation recovery time is the period from the cessation of sedative medication until the patient regains consciousness and can move according to commands.
Visual Analog Scale (VAS) score
Postoperatively, when a patient reaches an Aldrete score of 10 points through specialized nursing standard assessment, the patient fills out the visual analog scale (VAS) score based on their perioperative experience. The score is as follows: 0 points: no symptoms; 1–3 points: mild symptoms. 4–6 points: moderate symptoms. 7–10 points: severe symptoms.
Perioperative adverse reactions
The adverse reactions that occurred during the perioperative period, including reflux aspiration, nausea and vomiting, and the incidence of hypoxia, were recorded for both groups of patients. Hypoxia was defined as a decrease in SpO2 (75–90%) lasting for less than 60s.
Patient satisfaction
Before discharge, patients completed an in-hospital treatment/nursing satisfaction evaluation scale to assess their satisfaction. The score ranges from 0 to 100, with ≤60 points indicating dissatisfaction, 61–70 points indicating general satisfaction, 71–85 points indicating relatively satisfied, and >85 points indicating high satisfaction. The satisfaction rate is calculated as (general satisfaction + relatively satisfied + high satisfaction)/total number of people * 100%.
Statistical methods
Statistical analysis was conducted via SPSS 13.0 software. The measurement data are expressed as mean ± standard deviation, and t-tests were performed to compare data between the two groups. Sample sizes were expressed as numbers and percentages (%), with comparisons between two sample sizes via Chi-square tests or Fisher's exact test, where ordinal data were analyzed via rank-sum tests. Logistic regression analyses (univariate followed by multivariate) were performed to identify factors independently associated with cardia exposure. Variables with P<0.1 in univariate analysis or clinical relevance were included in the multivariate model. Statistical significance was set at P<0.05 (two-tailed).
Results
Comparison of gastric cardia exposure between the two groups
The degrees of gastric cardia exposure were 1, 2, 3, and 4 points for 12 patients (20.69%), 13 patients (22.41%), 19 patients (32.76%), and 14 patients (24.14%), respectively, in Group A and 21 patients (33.87%), 19 patients (30.65%), 18 patients (29.03%), and 4 patients (6.45%), respectively, in group B. Compared to Group B, Group A had a significantly greater degree of gastric cardia exposure (P < 0.05; Table 3).
Table 3.
Comparison of the degree of gastric cardia exposure between the two groups (n, %)
| Group | Exposure Degree (Points) | |||
|---|---|---|---|---|
| 1 | 2 | 3 | 4 | |
| A(n = 58) | 12(20.69) | 13(22.41) | 19(32.76) | 14(24.14) |
| B (n = 62) | 21(33.87) | 19(30.65) | 18(29.03) | 4(6.45) |
| χ2 | 9.039 | |||
| P | 0.029 | |||
Comparison of lesion types between moderate and deep sedation groups [n(%)]
Cardia lesions were significantly more frequent in the moderate sedation group (P < 0.05). Esophageal lesions showed markedly higher occurrence with moderate sedation (P < 0.05). No statistically significant differences were observed for: Bile reflux Gastric lesions (P > 0.05) (Table 4).
Table 4.
Comparison of disease detection types between the two groups
| Lesion Type | A (n = 58) | B (n = 62) | χ2 | P-value |
|---|---|---|---|---|
| Cardia lesions | 13(22.41) | 2 (3.23) | - | 0.001 |
| Esophageal lesions | 14 (24.14) | 3 (4.84) | - | 0.002 |
| Bile reflux | 28 (48.28) | 31 (50.00) | χ²=0.03 | 0.852 |
| Gastric lesions | 14 (24.14) | 14 (24.14) | χ²=0.04 | 0.838 |
Multivariable analysis of factors associated with cardia exposure status using logistic regression
Univariate analysis
BMI ≥ 30 was significantly associated with non-exposed cardia (OR = 0.21, 95% CI: 0.09–0.51, P = 0.001). Esophageal lesions Patients had a 6-fold increased risk of esophageal exposure (OR = 6.00, 95% CI: 1.01–35.71, P = 0.049) (Table 5).
Table 5.
.Univariate Analysis of Factors Associated with Cardia Exposure Status
| Variable | Cardia exposed (n=87) | Cardia completely unexposed (n=33) | OR (95% CI) | P-value |
|---|---|---|---|---|
| BMI classification | 0.21 (0.09–0.51） | 0.001 | ||
| - 25≤BMI<30 | 74 (85.06%) | 18 (54.55%) | ||
| - BMI≥30 | 13 (14.94%) | 15 (45.45%) | ||
| Complications | ||||
| - diabetes | 32 (36.78%) | 14 (42.42%) | 0.79 (0.36–1.74) | 0.572 |
| - hypertension | 28 (32.18%) | 10 (30.30%) | 1.09 (0.47–2.53) | 0.841 |
| - COPD | 24 (27.59%) | 12 (36.36%) | 0.67 (0.29–1.55) | 0.346 |
| gender | 1.00 (0.44–2.29) | 0.920 | ||
| -man | 29 (33.33%) | 11 (33.33%) | ||
| -woman | 58 (66.67%) | 22 (66.67%) | ||
| Lesion condition | ||||
| -Cardia lesions | 14 (16.09%) | 1 (3.03%) | 6.00 (1.01–35.71) | 0.049 |
| -Esophageal lesions | 15 (17.24%) | 2 (6.06%) | 3.23 (0.68–15.38) | 0.144 |
| -Bile reflux | 43 (49.43%) | 16 (48.48%) | 1.04 (0.47–2.30) | 0.930 |
| -Stomach lesions | 18 (20.69%) | 12 (36.36%) | 0.46 (0.19–1.10) | 0.079 |
Multivariate analysis
Logistic regression showed that obesity (BMI ≥ 30) was a protective factor for cardia exposure (aOR = 0.18, P = 0.001), while patients with cardia lesions had a significantly increased risk of cardia exposure (aOR = 5.82, P = 0.047). Other variables such as comorbidities and gastric lesions were not independently correlated (Table 6).
Table 6.
.Multivariable Analysis of Factors Associated with Cardia Exposure Status
| Variable | Cardia exposed (n=87) | Cardia completely unexposed (n=33) | aOR (95% CI) | P-value |
|---|---|---|---|---|
| BMI≥30 | 13 (14.94%) | 15 (45.45%) | 0.18 (0.07–0.47) | 0.001 |
| cardia lesions | 14 (16.09%) | 1 (3.03%) | 5.82 (1.02–33.33) | 0.047 |
Comparison of the sedation recovery time and sedation success rate between the two groups
The sedation recovery time was 10.08 ±2.18 and 15.38 ±3.25 in Groups A and B, respectively. The difference in sedation recovery time between the two groups was significant (P < 0.05). The sedation success rate was 94.83% and 96.77% in Groups A and B, respectively. The difference in the sedation success rate between the two groups was not significant (P >0.05; Table 7).
Table 7.
Comparison of perioperative adverse reactions between the two groups (n, %)
| Group | Recovery Time | Sedation Success Rate |
|---|---|---|
| A(n = 58) | 10.08 ±2.18 | 55(94.83) |
| B(n = 62) | 15.38 ±3.25 | 60(96.77) |
| Z/χ2 | −9.218 | 0.284 |
| P | 0.000 | 0.594 |
Comparison of the VAS scores between the two groups
In Group A, the distributions of the VAS scores were as follows: 0 points for 50 patients (86.21%), 1–3 points for five patients (8.62%), 4–6 points for three patients (5.17%), and 7–10 points for zero patients (0.00%). In Group B, the distribution was 0 points for 54 cases (87.10%), 1–3 points for four cases (6.45%), 4–6 points for four cases (6.45%), and 7–10 points for zero cases (0.00%). The VAS scores in Group A were similar to those in Group B (P > 0.05; Table 8).
Table 8.
Comparison of the VAS scores between the two groups
| Group | VAS Score | |||
|---|---|---|---|---|
| 0 | 1~3 | 4~6 | 7~10 | |
| A(n = 58) | 50(86.21) | 5(8.62) | 3(5.17) | 0(0.00) |
| B(n = 62) | 54(87.10) | 4(6.45) | 4(6.45) | 0(0.00) |
| Z | 0.275 | |||
| P | 0.872 | |||
Comparison of perioperative adverse reactions between the two groups
In Group A, the incidence rates of reflux aspiration, nausea and vomiting, hypoxia, and total adverse reactions were two (3.45%), four (6.90%), two (3.45%), and eight (13.79%) patients, respectively. In Group B, there were four (6.45%), three (4.84%), 11 (17.74%), and 18 (29.03%) patients, respectively. The proportion of hypoxia in Group B was significantly greater than that in Group A (P < 0.05). The total number of perioperative adverse reactions in Group A was significantly lower than that in Group B (P < 0.05; Table 9).
Table 9.
Comparison of perioperative adverse reactions between the two groups (n, %)
| Group | Reflux Aspiration | Nausea and Vomiting | Hypoxia | Total Adverse Reactions |
|---|---|---|---|---|
| A(n = 58) | 2(3.45) | 4(6.90) | 2(3.45) | 8(13.79) |
| B(n = 62) | 4(6.45) | 3(4.84) | 11(17.74) | 18(29.03) |
| χ2 | 0.112 | 0.231 | 8.543 | 4.100 |
| P | 0.737 | 0.631 | 0.003 | 0.049 |
No patients required advanced airway management (unplanned SGD insertion or orotracheal intubation). No patients required ACLS or died during the procedure.
Comparison of patient satisfaction with endoscopic examination between the two groups
In Group A, the distribution of satisfaction levels was as follows: very satisfied for 46 cases (79.31%), fairly satisfied for six cases (10.34%), moderately satisfied for five cases (8.62%), and dissatisfied for one case (1.72%). The overall satisfaction rate was 57 cases (98.28%). In Group B, 50 patients (80.65%) were very satisfied, four patients (6.45%) were fairly satisfied, six patients (9.68%) were moderately satisfied, two patients (3.23%) were dissatisfied, and the overall satisfaction rate was 60 patients (96.78%). The difference in patient satisfaction with endoscopic examination between the two groups was not significant (P >0.05; Table 10).
Table 10.
Comparison of patient satisfaction with endoscopic examination between the two groups (n, %)
| Group | Very Satisfied | Fairly Satisfied | Moderately Satisfied | Dissatisfied | Overall Satisfaction |
|---|---|---|---|---|---|
| A(n = 58) | 46(79.31) | 6(10.34) | 5(8.62) | 1(1.72) | 57(98.28) |
| B(n = 62) | 50(80.65) | 4(6.45) | 6(9.68) | 2(3.23) | 60(96.78) |
| χ2 | 0.000 | ||||
| P | 1.000 |
In this study, the anesthesia records indicated that, out of the moderate sedation group, two patients were converted to deep sedation, and one patient was converted to light sedation, resulting in a successful sedation rate of 94.83%.
Discussion
This study systematically evaluated the impact of moderate sedation using sufentanil combined with propofol on the exposure of the cardia during gastroscopy and its safety in overweight elderly patients. The results demonstrated that, compared to deep sedation, moderate sedation not only achieved a comparable sedation success rate but also significantly improved the exposure of the cardia, reduced the incidence of hypoxia, shortened recovery time, and did not increase the risk of reflux and aspiration in overweight elderly patients.
Adequate exposure of the cardia region is crucial for improving the quality of upper gastrointestinal endoscopy, particularly in high-risk populations such as elderly overweight patients. This study found that the degree of cardia exposure was significantly better under moderate sedation compared to deep sedation (P = 0.029). The underlying reason may be that an appropriate level of sedation preserves partial responsiveness in patients, enabling them to follow instructions (such as taking a deep breath) [17], thereby facilitating optimized visual exposure of the Z-line area.Possible mechanisms may include the following aspects [18, 19]: Voluntary contraction of the diaphragm during inspiration causes an increase in the esophagogastric junction pressure, and this pinchcock-like action of the crural part of the diaphragm is easily observed during endoscopy [17]. It is this action of the diaphragm that enables an excellent view of the esophagogastric junction or Z-line during endoscopy by contracting the skeletal muscles during deep inspiration, which lowers the crural part of the diaphragm enabling a 100% Z-line view.In contrast, although deep sedation improves patient comfort, it may cause constriction of the cardia and increased mucosal coverage, resulting in poor exposure of the cardia and thereby impairing lesion detection.
Regarding the choice of sedative medications, existing studies indicate that different drugs may have varying effects on cardia exposure [20]. A study [17] comparing the observation quality of the cardia during esophagogastroduodenoscopy in patients sedated with propofol, midazolam, and unsedated controls showed no significant difference in cardia exposure assessment between the propofol and midazolam groups.Meining et al similarly reported that [21], in terms of Z-line assessment, propofol provided comparable sedation efficacy to midazolam, but propofol performed better in other parameters related to endoscopic quality, demonstrating its potential advantages in overall examination quality. This study adopted a sedation protocol combining sufentanil with propofol. Due to the retrospective nature of the study, we were unable to directly compare the effects of different sedative medications on the exposure of the gastroesophageal junction under the same depth of sedation.
Multiple guidelines indicate that patients with an ASA classification of level III or higher and at risk of airway obstruction should undergo MAC (monitored anesthesia care) under the supervision of an anesthesiologist [22, 23]. MAC typically involves deep sedation. However, the results of this study suggest that for elderly overweight patients, prioritizing moderate sedation may offer greater advantages: not only is the incidence of complications during the procedure lower, but better exposure of the cardia can also be achieved. The data from this study show that the incidence of hypoxia in the moderate sedation group was only 3.45%, significantly lower than the 17.74% in the deep sedation group (P < 0.05), and the overall incidence of adverse events was also lower (13.79% vs. 29.03%, P = 0.049). This difference may be closely related to the physiological characteristics of elderly overweight patients: this population often has reduced cardiopulmonary function, decreased drug metabolism rates, and weakened respiratory compensatory capacity, making them more susceptible to respiratory depression and hemodynamic fluctuations under deep sedation [24, 25]. Although there was no statistically significant difference in the incidence of reflux and aspiration between the two groups, theoretically, the preserved swallowing reflex and arousal ability in moderate sedation may help reduce such risks.
Additionally, the recovery time in the moderate sedation group was significantly shorter than that in the deep sedation group (10.08 ± 2.18 min vs. 15.38 ± 3.25 min, P < 0.05). This finding is consistent with the pharmacokinetic profile of propofol and the difference in dosage used, suggesting that moderate sedation is more conducive to improving the operational efficiency of the endoscopy unit.
It is noteworthy that multivariate analysis revealed that obesity (BMI ≥ 30) may be a protective factor for gastroesophageal junction exposure (aOR = 0.18, P = 0.001), while cardia lesions significantly increased the risk of difficult exposure (aOR = 5.82, P = 0.047). This finding suggests that the mechanism of gastroesophageal junction exposure is complex, potentially involving multiple factors such as mechanical support, pressure dynamics, and mucosal pathology [26, 27]. Further investigation is needed to elucidate the underlying mechanisms and clinical implications. Although our study was not prospective, it suggests that overweight patients, particularly elderly obese patients (BMI≧30), require closer endoscopic monitoring for mucosal changes at the gastric cardia.
To summarize,for elderly overweight patients, a high-risk population, the use of moderate sedation during gastroscopy significantly improves cardia exposure compared to deep sedation. Patients under moderate sedation can still follow instructions such as deep inspiration, thereby achieving a clearer view of the dentate line while maintaining a high sedation success rate. This finding provides an important basis for developing individualized sedation protocols for high-risk populations and has positive implications for enhancing the quality of gastroscopy and the detection rate of early lesions.
This study has several limitations. First, as a single-center retrospective study, it is susceptible to selection bias. Second, the assessment of gastroesophageal junction exposure relied on the subjective evaluation of the endoscopist and was not recorded in real-time using a blinded method. Third, the sample size was relatively small, and long-term outcomes such as cognitive function were not evaluated. Fourth, the impact of different sedative medications on gastroesophageal junction exposure at equivalent depths of sedation was not investigated. Future multicenter prospective studies utilizing standardized assessment tools are warranted to further validate the advantages of moderate sedation in the elderly overweight population.
Supplementary Information
Acknowledgements
Department of Gastroenterology and Endoscopy Center, the Affiliated Hospital of Qingdao University.
Conflict of interest
There is no conflict of interest among the authors of the article.
Abbreviations
- VAS
Visual analog scale
- BMI
Body mass index
- COPD
Chronic obstructive pulmonary disease
- ASA
American Society of Anesthesiologists
- SPO2
Peripheral capillary oxygen saturation
- MOAA/S
Modified Observer’s Assessment of Alertness/Sedation
- MAP
Mean Arterial Pressure
- HR
Heart rate
- SGD
Sebaceous Gland Duct
- ACLS
Advanced Cardiovascular Life Support
- MAC
Monitored Anesthesia Care
Author contributions
Author contributions: Qi LJ was responsible for the conception and design of the study, performed the study, and wrote the manuscript. Zhou ZG participated in the study, provided experimental data and performed statistical analysis. Peng K, Yu N and Wang L provided suggestions in technology application and data analysis. Ji XY was responsible for conception and design of the study, and guided the revision of the thesis.ZhangYwas responsible for conception and design of the study, and manuscript authorization.All authors approved the final version of this manuscript.
Funding
None.
Data availability
All the data in this study are shown in the manuscript. Unprocessed data are available from the corresponding author upon reasonable request.
Declarations
Ethics approval and consent to participate
This study was performed in accordance with the ethical principles of the Declaration of Helsinki. This study was approved by the Ethics Committee of the Affiliated Hospital of Qingdao University (Approval No. QYFYWZLL27303). This is a retrospective study and individual informed consent to participate for this retrospective analysis with routine clinical data was waived by the Ethics Committee of the Affiliated Hospital of Qingdao University.
Consent for publication
Not applicable.
Competing interests
The authors declare no competing interests.
Footnotes
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Yong Zhang and Xiangyu Ji contributed equally as co-corresponding authors.
Contributor Information
Xiangyu Ji, Email: Davidjxy@sina.com.
Yong Zhang, Email: zhangyongdoc@163.com.
References
- 1.McColl KE. Cancer of the gastric cardia. Best Pract Res Clin Gastroenterol. 2006;20:687–96. [DOI] [PubMed] [Google Scholar]
- 2.Drahos J, Wu M, Anderson WF, et al. Regional variations in esophageal cancer rates by census region in the united States[J], 1999–2008. PLoS ONE. 2013;8:e67913. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Matsueda K, Manabe N, Watanabe T, et al. Adenocarcinoma of the esophagogastric junction: characteristics of female patients and young adult patients based on a 12-year retrospective and prospective multicenter clinicoepidemiological cohort study in Japan. BMC Gastroenterol. 2024;24(1):342. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Felley C, Bouzourene H, VanMelle MB, et al. Age, smoking and overweight contribute to the development of intestinal metaplasia of the cardia[J]. World J Gastroenterol. 2012;18(17):2076–83. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Rompen IF, Crnovrsanin N, Nienhüser H. Age-dependent benefit of neoadjuvant treatment in adenocarcinoma of the esophagus and gastroesophageal junction: a multicenter retrospective observational study of young versus old patients. Int J Surg. 2023;109(12):3804–14. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Festi D, Scaioli E, Baldi F, et al. Body weight, lifestyle, dietary habits and gastroesophageal reflux disease. World J Gastroenterol. 2009;15:1690–701. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Hjartåker A, Langseth H, Weiderpass E. Obesity and diabetes epidemics: cancer repercussions[J]. Adv Exp Med Biol. 2008;630:72–93. [DOI] [PubMed] [Google Scholar]
- 8.Raina H, Prakash A, Ashraf U, et al. Is endoscopist-directed sedation for endoscopic retrograde cholangiopancreatography with balanced propofol solution (BPS) practical and safe? A prospective study from a tertiary care centre in India. Gastroenterol Rev. 2021;16(4):324–9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Fatima H, Imperiale T. Safety profile of endoscopist-directed balanced propofol sedation for procedural sedation: an experience at a hospital-based endoscopy unit. J Clin Gastroenterol. 2022;56(3):e209-15. [DOI] [PubMed] [Google Scholar]
- 10.Chen Z, Liu L, Tu J, et al. Improvement of atropine on esophagogastric junction observation during sedative esophagogastroduodenoscopy. PLoS One. 2017;12(6):e0179490. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 11.Odze RD. Pathology of the gastroesophageal junction. Semin Diagn Pathol. 2005;22:256–65. [DOI] [PubMed] [Google Scholar]
- 12.Riddell RH. The biopsy diagnosis of gastroesophageal reflux disease, carditis, and Barrett’s esophagus, and sequelae of therapy. Am J Surg Pathol. 1996;20(Suppl 1):S31-50. [DOI] [PubMed] [Google Scholar]
- 13.Petersson F, Franzén LE, Borch K. Characterization of the gastric cardia in volunteers from the general population. Type of mucosa, Helicobacter pylori infection, inflammation, mucosal proliferatiactivity, p53 and p21 expression, and relations to gastritis. Dig Dis Sci. 2010;55:46–53. [DOI] [PubMed] [Google Scholar]
- 14.Chen SH, Yuan TM, Zhang J, et al. Remimazolam tosilate in upper gastrointestinal endoscopy: a multicenter, randomized, non-inferiority, phase III trial. Gastroenterol Hepatol. 2021;36(2):474–81. [DOI] [PubMed] [Google Scholar]
- 15.Chen M, Lu Y, Liu H, et al. The propofol-sparing effect of intravenous Lidocaine in elderly patients undergoing colonoscopy: a randomized, double-blinded, controlled study. BMC Anesthesiol. 2020;20(1):132. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16.Douglas K, Rex MD, Raj Bhandari, et al. A phase III study evaluating the efficacy and safety of remimazolam (CNS 7056) compared with placebo and Midazolam in patients undergoing colonoscopy[J]. Gastrointest Endosc. 2018;88(3):427–37. [DOI] [PubMed] [Google Scholar]
- 17.Chen Z, Liu L, Tu J, et al. Improvement of atropine on esophagogastric junction observation during sedative esophagogastroduodenoscopy. PLoS ONE. 2017;12(6):e0179490. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 18.Mittal RK, Shaffer HA, Parollisi S, et al. Influence of breathing pattern on the esophagogastric junction pressure and esophageal transit[J]. Am J Physiol. 1995;269:G577–83. [DOI] [PubMed] [Google Scholar]
- 19.Mittal RK, Rochester DF, McCallum RW. Effect of the diaphragmatic contraction on lower oesophageal sphincter pressure in man. Gut. 1987;28:1564–8. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 20.Fujii Y, Hoshi T, Takahashi S, et al. Propofol decreases diaphragmatic contractility in dogs. Anesth Analg. 1999;89:1557–60. [DOI] [PubMed] [Google Scholar]
- 21.Meining A, Semmler V, Kassem AM, et al. The effect of sedation on the quality of upper gastrointestinal endoscopy: an investigator-blinded, randomized study comparing propofol with midazolam. Endoscopy. 2007;39:345–9. [DOI] [PubMed] [Google Scholar]
- 22.Practice Guidelines for Moderate Procedural Sedation and Analgesia. 2018: A Report by the American Society of Anesthesiologists Task Force on Moderate Procedural Sedation and Analgesia, the American Association of Oral and Maxillofacial Surgeons, American College of Radiology, American Dental Association, American Society of Dentist Anesthesiologists, and Society of Interventional Radiology. Anesthesiology. 2018;128(3):437–479. [DOI] [PubMed]
- 23.Benzoni T, Agarwal A, Cascella M, Procedural S. 2025 Mar 22. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2025. [PubMed]
- 24.Zhu H, Su Z, Zhou H et al. Remimazolam dosing for gastroscopy: A randomized noninferiority Trial[J].ANESTHESIOLOGY. 2024;1,140(3):409–41623. [DOI] [PubMed]
- 25.Ye E, Wu K, Ye H, et al. Comparison of 95% effective dose of remimazolam besylate and propofol for gastroscopy sedation on older patients: a single-centre randomized controlled trial. Br J Clin Pharmacol. 2023;89(11):3401–10. [DOI] [PubMed] [Google Scholar]
- 26.Jacobson BC, Somers SC, Fuchs CS, et al. Body-mass index and symptoms of gastroesophageal reflux in wome[J]. N Engl J Med. 2006;354(22):2340–8. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 27.Fang Y, Xu Y, Cao S, et al. Incidence and risk factors for hypoxia in deep sedation of propofol for artificial abortion patients. Front Med Lausanne. 2022;9:763275. [DOI] [PMC free article] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Data Availability Statement
All the data in this study are shown in the manuscript. Unprocessed data are available from the corresponding author upon reasonable request.