Abstract
Background
Overweight and obesity are prevalent modern health issues. It has been suggested that individuals who are overweight or obese are more likely to experience hypoxemia during gastrointestinal endoscopy. Ciprofol has demonstrated advantages over propofol in endoscopic procedures, including lower rates of respiratory depression among normal-weight populations. This study aimed to compare the incidence of hypoxemia between ciprofol and propofol in overweight and obese patients undergoing gastrointestinal endoscopy.
Methods
A total of 176 patients were randomly assigned to receive either ciprofol or propofol. The primary outcome was the incidence of hypoxemia, defined as pulse oxygen saturation (SpO2) < 90%. Additional variables recorded included the lowest SpO2, recovery times, injection pain, and hypotension.
Results
Although the incidence of hypoxemia (SpO2 < 90%) was lower in the ciprofol group compared to the propofol group (10.2% vs. 18.2%, p = 0.131), this difference was not statistically significant. Similarly, the incidence of SpO2 < 95% showed no significant difference between the two groups (34.1% vs. 44.3%, p = 0.165). However, the incidence of injection pain was significantly lower in the ciprofol group (0% vs. 40.9%, p < 0.001), as was the incidence of hypotension (25.0% vs. 42.0%, p = 0.017).
Conclusions
The findings of this study indicate that ciprofol offers sedation effects comparable to those of propofol, without significantly altering the incidence of hypoxemia in overweight and obese patients undergoing gastrointestinal endoscopy. However, additional evidence is required to validate these findings due to the limitations posed by the sample size.
Trial registration
The study was registered with the Chinese Clinical Trial Registry at www.chictr.org.cn (registration date: July 22nd 2024, registration number: ChiCTR2400087170).
Supplementary Information
The online version contains supplementary material available at 10.1186/s12871-025-03428-w.
Keywords: Ciprofol, Hypoxemia, Gastrointestinal endoscopy, Overweight, Obesity
Introduction
Overweight and obesity are significant modern public health challenges. According to World Health Organization (WHO) data, in 2022, 43% of adults aged 18 years and older were classified as overweight, while 16% were living with obesity (https://www.who.int/news-room/fact-sheets/detail/obesity-and-overweight). In China, a real-world study indicated that more than one-third of the population is overweight [1]. It has been suggested that individuals with obesity are more likely to experience hypoxemia during gastrointestinal endoscopy [2, 3]. Additionally, increasing body mass index (BMI) has been associated with a higher incidence of hypoxemia [4]. Reports indicate that the incidence of hypoxemia during gastrointestinal endoscopy can vary widely, ranging from less than 10% to over 80% [5, 6].
Propofol has become a widely used agent for sedation in gastrointestinal endoscopy, as well as for the induction and maintenance of anesthesia, due to its rapid onset and quick recovery profile. However, there are notable limitations associated with propofol, including injection pain, hypotension, and respiratory depression leading to apnea [7, 8]. Recently, a new agent named ciprofol (working name: HSK3486) has been explored for clinical use, particularly in the context of gastrointestinal endoscopy, and has demonstrated comparable sedative efficacy to propofol [9, 10]. In prior studies, ciprofol has shown advantages over propofol, including reduced injection pain, lower rates of respiratory depression, and decreased hypotension [11]. However, it is important to note that these studies predominantly included participants of normal weight. The impact of ciprofol on the incidence of hypoxemia in overweight and obese patients undergoing gastrointestinal endoscopy remains unclear. Therefore, the present study was designed to compare the incidence of hypoxemia between ciprofol and propofol in this specific patient population.
Methods
Ethical statement
This study was approved by the Institutional Review Board of the Seventh Affiliated Hospital of Sun Yat-sen University (chairperson: Professor Chun Chen, approval number: KY-2024-082-03) on 12/07/2024. This prospective randomized controlled study was performed in accordance with the principles of the Declaration of Helsinki. The study was registered in the Chinese Clinical Trial Registry at www.chictr.org.cn (registration date: 22/07/2024; registration number: ChiCTR2400087170, URL: https://www.chictr.org.cn/showproj.html?proj=238283). This study adhered to the CONSORT 2025 checklist.
Study populations
All Chinese patients scheduled for elective gastroscopy, colonoscopy, or both under anesthesiologist-directed sedation from August 11, 2024 in Seventh Affiliated Hospital of Sun Yat-sen University, were considered for inclusion in the study. The inclusion criteria were as follows: (i) age between 18 and 70 years; (ii) American Society of Anesthesiologists (ASA) physical status I–II; (iii) body mass index (BMI) of 24 kg/m² or higher; (iv) the operation time is expected to be no more than 60 min; and (v) provision of informed written consent by the patient. The exclusion criteria were as follows: (i) requiring complex endoscopic diagnostic and therapeutic techniques, including but not limited to cholangiopancreatography, endoscopic mucosal resection, endoscopic submucosal dissection, and oral endoscopic muscle dissection; (ii) planned for intubation; (iii) with pulse oxygen saturation (SpO2) levels ≤ 95% upon entering the procedure room; (iv) diagnosed with obstructive sleep apnea syndrome (OSAS); (v) with severe cardiovascular conditions, including but not limited to severe arrhythmias, heart failure, Adams-stokes Syndrome, unstable angina pectoris, myocardial infarction within the past six months, a history of tachycardia or bradycardia requiring medical treatment, and third-degree atrioventricular block; (vi) presenting with systolic blood pressure ≥ 180 mmHg and/or diastolic blood pressure ≥ 110 mmHg upon entry into the procedure room; (vii) with respiratory insufficiency or a history of obstructive lung diseases, and with uncontrolled clinically significant liver, kidney, hematologic, neurologic, or metabolic disorders, as determined by the investigator; (viii) pregnant or lactating women; (ix) with known allergies to eggs, soy products, opioids and their rescue medications, propofol, or other related substances; (x) a history of alcohol abuse within the past three months, defined as an average daily consumption exceeding two units of alcohol ((1 unit = 360mL beer or 45mL 40% alcohol by volume liquor or 150mL wine); (xi) with a history of craniocerebral injury, potential convulsions, myoclonus, intracranial hypertension, cerebral aneurysm, or cerebrovascular accidents; (xii) diagnosed with schizophrenia, intellectual disabilities, mania, insanity, long-term psychotropic drug use, substance addiction, cognitive dysfunction, or similar conditions; (xiii) deemed unsuitable for participation in this trial by the investigator.
Overweight was defined as a BMI of 24 kg/m² or higher, while obesity was defined as a BMI of 28 kg/m² or higher, in accordance with Chinese standards [1, 12].
Procedures
Pulse oxygen saturation (SpO2), heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), respiratory rate (RR), and a standard 3-lead electrocardiogram (ECG) were continuously monitored for all participants. Prior to the initiation of sedation, all patients received oxygen at a flow rate of 5 L per minute through a nasal cannula for 5 min. Oxygen administration was maintained throughout the entire procedure. Both groups were administered 50 µg of fentanyl intravenously over a period of no less than 10 s. Patients in the propofol group received a propofol bolus of up to 2 mg/kg based on their ideal body weight (IBW), administered intravenously within 30 s. The IBW was calculated as is calculated by subtracting 100 from an individual’s height in centimeters for males, and subtracting 105 for females. Following this, a propofol infusion was titrated until the patients achieved a Modified Observer’s Assessment of Alertness/Sedation (MOAA/S) score of ≤ 1 [13–15]. In the ciprofol group, patients received a ciprofol bolus of up to 0.4 mg/kg based on ideal body weight, also administered within 30 s, followed by a titration of ciprofol until the MOAA/S score ≤ 1. If a successful reduction of the MOAA/S score to ≤ 1 was not achieved within 2 min after 2 supplemental doses, the induction was considered a failure. Once the MOAA/S score reached ≤ 1, a colonoscope or gastroscope was inserted. Anesthesiologists refrained from intervening unless the SpO2 dropped below 95% for 30 s or continued to decline. In such cases, anesthesiologists employed one or more of the following techniques: chin lift, jaw thrust, increased FiO2, or placement of a nasopharyngeal airway. If these measures proved ineffective, additional interventions were implemented, including positive pressure ventilation with a mask, extraction of the gastroscope, placement of a laryngeal mask, or endotracheal intubation. An observer meticulously recorded all outcomes, including the lowest oxygen saturation levels.
Patients were required to gargle and retain 0.1 g of dyclonine hydrochloride mucilage oral gel at the back of their throat, then swallow it 10 to 15 min before the gastroscopy. Additionally, 0.1 g of tetracaine hydrochloride jelly should be applied topically to the anus 1 to 2 min prior to the colonoscopy. Although end-tidal carbon dioxide (etCO2) monitoring is recommended for gastrointestinal endoscopy in high-risk patients [16], the limitations of the monitoring conditions prevented us from conducting measured etCO2 monitoring in the present study.
Randomization and blind
Subjects were randomly assigned to either the propofol or ciprofol group by YD, using random numbers generated by SPSS in a 1:1 ratio. The assignment numbers were sealed in envelopes until the participants were ready to receive their respective interventions. For both propofol and ciprofol, the formulations had a similar milky appearance. The outcome assessors, gastrointestinal performers, and patients were all blinded to the group assignments.
The outcomes
The aim of this study is to compare the incidence of hypoxemia (defined as SpO2 < 90%) in overweight and obese adults (BMI ≥ 24) undergoing gastrointestinal endoscopy who receive ciprofol versus those who receive propofol. Additionally, other variables were recorded, including the lowest SpO2, recovery times, injection site pain, and hypotension (defined as a decrease in MAP of more than 20% from baseline). Non-invasive blood pressure measurements were taken automatically at 3-minute intervals. The costs of ciprofol and propofol were also compared.
Sample size
According to prior studies, the incidence of hypoxemia (SpO2 < 90%) in individuals with obesity or overweight is reported to be over 45% [2, 17]. We assumed a baseline hypoxemia incidence of 40% in the propofol group, with the ciprofol group expected to reduce this incidence to 20%. To achieve a statistical power of 80% with a Type I error rate of 0.05, a total of 88 participants were required in each group, accounting for a 10% dropout rate.
Statistical analysis
Statistical analyses were performed using the Statistical Package for the Social Sciences (version 24.0; IBM Corporation, Armonk, NY, USA), and R version 4.5.2 (R Foundation for Statistical Computing, Vienna, Austria; http://www.r-project.org accessed on 5 July 2025). Quantitative data were expressed as means ± standard deviations for normally distributed data, or as medians with interquartile ranges (IQRs) for non-normally distributed data. Qualitative and ordinal data were presented as absolute frequencies. The normality of quantitative data was assessed using the one-sample Kolmogorov-Smirnov test. To compare quantitative data between the two groups, either an independent t-test or a non-parametric test was utilized, depending on the data distribution. Mean differences between groups, along with the 95% confidence intervals (CIs), were also reported. For qualitative or ordinal data, differences were evaluated using the chi-square test or Fisher’s exact probability test. Proportions with 95% confidence intervals (CIs) were estimated using the Wilson method. Absolute differences (AD) between groups, along with their 95% CIs, were calculated using the Newcombe method. Additionally, relative risk (RR) with a 95% CI was also determined. Subgroup analyses were also performed for patients with obesity and those who underwent both gastroscopy and colonoscopy. Statistical significance was defined as two-tailed p-values of less than 0.05. Graphical representations of the data were generated using Origin (version 2025 8.1; OriginLab Corporation, Northampton, MA, USA).
Results
A total of 176 patients were recruited and included in the final analysis of this study from August 11, 2024 to October 15, 2024. The inclusion procedure is illustrated in the flow chart (Fig. 1).
Fig. 1.
The flow chart of inclusion and exclusion
Baseline characteristics
The baseline characteristics, including age, gender, BMI, and ASA distribution, were comparable between the ciprofol and propofol groups (Table 1). Additionally, Mallampati grade and self-reported history of snoring showed no significant differences between the two groups (Table 1). The types of procedures performed were also comparable between the groups (Table 1).
Table 1.
Participants’ characteristics of total participants
| Participants’ characteristic | Ciprofol (88) | Propofol (88) | P |
|---|---|---|---|
| Age (years) | 45.6 ± 11.8 | 44.8 ± 10.8 | 0.608 |
| Male, n (%) | 54 (61.4%) | 59 (67.1%) | 0.432 |
| ASA | 0.635 | ||
| I, n (%) | 9 (10.2%) | 11 (12.5%) | |
| II, n (%) | 79 (89.8%) | 77 (87.5%) | |
| Height (centimeters) | 165.9 ± 8.5 | 166.5 ± 7.9 | 0.626 |
| Weight (kilograms) | 77.6 ± 13.3 | 77.9 ± 10.8 | 0.885 |
| BMI (kilogram/meter2) | 0.364 | ||
| 24 ≤ BMI < 28 | 51 (58.0%) | 44 (50.0%) | |
| 28 ≤ BMI | 37 (42.0%) | 44 (50.0%) | |
| Hypertension, n (%) | 16 (18.2%) | 21 (23.9%) | 0.355 |
| Snore, n (%) | 62 (70.5%) | 69 (78.4%) | 0.226 |
| Mallampati classification | 0.600 | ||
| 1, n (%) | 15 (17.0%) | 10 (11.3%) | |
| 2, n (%) | 43 (48.9%) | 49 (55.7%) | |
| 3, n (%) | 16 (18.2%) | 18 (20.5%) | |
| 4, n (%) | 14 (15.9%) | 11 (12.5%) | |
| Procedure type | 0.643 | ||
| Gastroscopy, n (%) | 22 (25.0%) | 26 (29.5%) | |
| Colonoscopy, n (%) | 8 (9.1%) | 10 (11.4%) | |
| Both, n (%) | 58 (65.9%) | 52 (59.1%) |
Abbreviations: ASA American society of Aneshesiologists, BMI Body Mass Index
Outcomes
The incidence of hypoxemia was 10.2% (95% CI, 5.5 to 18.3%) in the ciprofol group and 18.2% (95% CI, 11.5 to 27.5%) in the propofol group. The absolute difference (AD) between groups (ciprofol–propofol) was − 8.0% (95% CI, − 18.7 to 2.5%), and the risk ratio (RR) was 0.56 (95% CI, 0.26 to 1.20). Similarly, the incidence of SpO2 < 95% did not differ significantly between the two groups (34.1% vs. 44.3%, AD=-10.2%, 95%CI, -24.3% to 4.2%, p = 0.165, Table 2; Fig. 2a).
Table 2.
Participants’ outcomes of total participants
| Participants’ outcomes | Ciprofol (88) | Propofol (88) | AD, 95% CI | RR, 95% CI | MD, 95% CI | P |
|---|---|---|---|---|---|---|
| SpO2 < 95% | 34.1% (25.0–44.5%) # | 44.3% (34.4–54.7%) # | −10.2% (−24.3–4.2%) | 0.77 (0.53–1.12) | – | 0.165 |
| SpO2 < 90% | 10.2% (5.5–18.3%) # | 18.2% (11.5–27.5%) # | −8.0% (−18.7–2.5%) | 0.56 (0.26–1.20) | – | 0.131 |
| Induction time (s) | 50.5 ± 22.6 | 46.5 ± 15.7 | – | – | 4.0 (−1.7–9.8) | 0.170 |
| Operation time (min) | 26.6 ± 14.2 | 25.1 ± 13.6 | – | – | 1.4 (−2.7–5.6) | 0.500 |
| Anesthesia time (min) | 23.4 ± 13.7 | 21.8 ± 13.4 | – | – | 1.7 (−2.4–5.7) | 0.418 |
| Recovery time (min) | 7.6 ± 3.3 | 6.8 ± 2.9 | – | – | 0.7 (−0.2–1.7) | 0.124 |
| Injection pain | 0 | 40.9% (31.2–51.4%) # | −40.9% (−51.4– −31.2%) | – | – | < 0.001 |
| Hypotension | 25.0% (17.1–35.0%) # | 42.0% (32.3–52.5%) # | −17.0% (−30.4– −3.1%) | 0.59 (0.38–0.92) | – | 0.017 |
| Hospitalization expenses (China yuan) | 138.7 ± 41.2 | 7.2 ± 2.5 | – | – | 131.4 (122.7–140.2) | < 0.001 |
Abbreviations: AD absolute difference, CI Confidence Interval, RR relative ratio, MD mean difference, SpO2 pulse oxygen saturation, s second, min minute
# Qualitative data were presented as proportion with 95% CIs estimated using the Wilson method
Fig. 2.
The hypoxemia incidence. a, the total participants; b, participants undergoing both gastroscopy and colonoscopy; c, obese participants; ns: not significant
Both injection pain (0% vs. 40.9%, AD= -40.9%, 95%CI, -51.4% to -31.2%, p < 0.001, Table 2) and hypotension (25.0% vs. 42.0%, AD=-17.0%, 95%CI, -30.4% to -3.1%, p = 0.017, Table 2; Fig. 3a) were significantly lower in the ciprofol group compared to the propofol group.
Fig. 3.
The hypotension incidence. a, the total participants; b, participants undergoing both gastroscopy and colonoscopy; c, obese participants; * p < 0.05; ns: not significant
Regarding interventions for hypoxemia, there were no significant differences between the two groups (Fig. 4).
Fig. 4.
The interventions for hypoxemia. a, the total participants; b, participants undergoing both gastroscopy and colonoscopy; c, obese participants; ns: not significant
Subgroup analyses
Gastrointestinal endoscopy
In patients who underwent both gastroscopy and colonoscopy, the incidence of hypoxemia (SpO2 < 90%) was not significantly different between the ciprofol and propofol groups (6.9% vs. 19.2%, AD=-12.3%, 95%CI, -26.1% to 0.2%, p = 0.053, Fig. 2b). However, the incidence of hypotension was significantly lower in the ciprofol group compared to the propofol group (25.9% vs. 50.0%, AD= -24.1%, 95%CI, -41.0% to -6.0%, p = 0.009, Fig. 3b).
Obese patients
Among the 81 obese patients (BMI ≥ 28 kg/m²) included in this study, baseline characteristics were similar between the ciprofol and propofol groups. The incidence of hypoxemia (SpO2 < 90%) was not significantly different between the two groups (18.9% vs. 27.3%, AD=-8.4%, 95%CI, -26.4% to 10.7%, p = 0.377, Fig. 2c). Likewise, the incidences of hypotension were not significantly different (29.7% vs. 40.9%, AD= -11.2%, 95%CI, -31.0% to 10.0%, p = 0.296, Fig. 3c).
Cost
The cost was significantly higher in the ciprofol group compared to the propofol group (138.7 ± 41.2 Y/person vs. 7.2 ± 2.5 Y/person, p < 0.001).
Discussion
The present study demonstrated that, in overweight and obese patients undergoing gastrointestinal endoscopy, there was no significant difference in the incidence of hypoxemia when compared to propofol.
In 2022, it was estimated that more than half of adults worldwide were overweight or obese (https://www.who.int/en/news-room/fact-sheets/detail/obesity-and-overweight). As a result, both surgical and non-surgical procedures are increasingly performed on overweight and obese patients. Non-surgical procedures, such as gastrointestinal endoscopy, are often conducted under sedation to facilitate the process [18]. This necessitates that anesthesia and sedation providers carefully consider the associated management risks for these patients. Sedation management in overweight and obese individuals poses challenges due to associated pathophysiological changes [19]. Overweight patients are particularly susceptible to developing obstructive sleep apnea due to anatomical alterations. Therefore, to minimize the risk of hypoxemia during gastrointestinal endoscopy, anesthesia and sedation providers must develop and implement carefully considered sedation plans and management strategies [20].
Propofol is widely used in ambulatory gastrointestinal endoscopy due to its rapid onset and recovery. Ciprofol, a newly developed drug, has a similar active structure to propofol [21]. The 50% effective concentration of ciprofol on γ-aminobutyric acid type A (GABAA) receptors is lower than that of propofol [21], and ciprofol’s affinity for GABAA is approximately 4–5 times greater than that of propofol [22]. While the efficacy of ciprofol is comparable to that of propofol, previous studies have indicated that it has a longer induction time in general anesthesia or sedation [23–25]. The present study found that ciprofol and propofol were comparable in terms of both induction success and induction time in overweight and obese patients.
Hypotension, injection pain, and hypoxemia are the most common adverse events (AEs) associated with propofol sedation and induction [7, 8, 26]. The incidence of hypoxemia related to propofol sedation is particularly prevalent during endoscopic procedures [3]. The hypoxemia incidences increased in obese patients, and BMI was correlated to hypoxemia in ambulatory endoscopy [2, 27–29]. While BMI has been identified as a statistically significant covariate in the pharmacokinetics of ciprofol, it does not significantly affect its pharmacodynamics [30]. The question of whether ciprofol is superior to propofol in reducing the incidence of hypoxemia remains controversial, even among normal-weight patients, according to previous studies [10, 31]. A retrospective study indicated no significant differences between obese and non-obese patients concerning most endoscopy-related outcomes [32]. Additionally, two recent meta-analyses suggested that ciprofol could significantly reduce respiratory depression in comparison to propofol [23, 33]. However, only two studies addressing hypoxemia were included in one of the meta-analyses, which found that ciprofol could lower the incidence of hypoxemia in normal-weight patients [33]. In contrast, the present study, which included overweight and obese patients undergoing sedation for gastrointestinal endoscopy, found that ciprofol did not result in a lower incidence of hypoxemia. The comparative effectiveness of ciprofol versus propofol in reducing the incidence of intraoperative hypotension in normal weight patients remains a subject of debate [34, 35]. The present results suggested that ciprofol significantly reduced the incidence of hypotension in overweight and obese patients. This may be attributed to the stronger GABAA receptor binding activity of cipofol, which exhibits equivalent potency to propofol at just 1/4 to 1/5 of the dosage [36]. Injection-site pain is one of the most frequently reported adverse reactions, causing discomfort, anxiety, and even resistance in patients undergoing sedation. In terms of injection pain and physician satisfaction, ciprofol has been shown to be superior to propofol in prior studies [13, 31]. Consistent with these findings, the present study also indicated that ciprofol significantly reduced injection pain compared to propofol in overweight and obese patients.
Hypotension during induction is another common adverse reaction associated with propofol. A recent meta-analysis found no significant differences between ciprofol and propofol regarding induction or maintenance in general anesthesia [37]. In contrast, another meta-analysis suggested that ciprofol could reduce the likelihood of hypotension during painless endoscopy [38]. The present study demonstrated that, in overweight and obese patients undergoing gastrointestinal endoscopy, ciprofol significantly decreased the incidence of hypotension.
Rapid recovery is one of the most important concerns for sedation in non-operating room settings. Recent meta-analyses have found no significant differences between ciprofol and propofol regarding awakening time in patients in non-operative settings [23, 33, 38]. Consistent with these findings, the results of the present study indicated no difference in awakening time between ciprofol and propofol in overweight and obese patients undergoing gastrointestinal endoscopy.
Furthermore, the cost of ciprofol should be considered in its widespread use. In mainland China, ciprofol is ten times more expensive than domestic propofol. If the advantages of ciprofol over propofol are limited to reduced injection pain and decreased hypotension during induction, the universal adoption of ciprofol may not be justified due to its higher cost.
Several limitations of the present study should be acknowledged. First, it was a single-center study with a limited number of participants in China, and the results need to be confirmed by studies with larger populations, multiple centers and regions. It is important to note that the study’s power calculation was based on an assumed incidence of hypoxemia of 40% in the propofol group, with a hypothesized reduction to 20% in the ciprofol group. However, the actual incidence observed in the propofol group was significantly lower, at 18.2%. This discrepancy indicates that the study may have been underpowered to detect a true difference between the groups, which could potentially result in a Type II error concerning the non-significant p-value (p = 0.131) for the primary outcome. Second, to minimize harm, interventions were performed when SpO2 was below 95%. This “prophylactic” intervention may obscure the true difference in respiratory depression between the two drugs. Additionally, preoxygenation prior to sedative gastrointestinal endoscopy is a standard practice at our medical center. As a result, the incidence of hypoxemia (SpO2 < 90%) in the present study was lower than in prior studies [2, 17]. Third, there are several methods for calculating ideal body weight (IBW), and we utilized only one of these approaches. Additionally, the induction doses of ciprofol and propofol were based on ideal body weight derived from normal-weight participants. The dosing of ciprofol used in painless endoscopy has varied in previous studies, and data on its use in overweight and obese patients are limited [39, 40]. A prior study suggests that administering ciprofol based on IBW rather than lean body weight (LBW) may result in better anaesthesia for gastroscopy in obese patients [14]. A separate study indicated that using corrected body weight (CBW) to determine the dose of ciprofol is more reliable for gastroscopy in overweight and obese patients [16]. Consequently, the choice of an ideal body weight (IBW)-based dose could significantly impact the outcomes. Fourth, the subgroup analyses for patients undergoing combined procedures and for obese patients were exploratory in nature, and the sample size was not sufficiently powered to draw definitive conclusions for these groups. Therefore, the results of these exploratory subgroup analyses should be validated in future studies. Last but not least, while patients with diagnosed OSAS were excluded from the study, it remains unclear whether patients with undiagnosed OSAS were included. Not all individuals with suspected OSAS undergo sleep monitoring. However, the randomization in the present study helps to minimize any potential hypoxemia bias associated with those who may have undiagnosed OSAS.
The present study demonstrated that, in overweight and obese patients undergoing gastrointestinal endoscopy, there was no significant difference in the incidence of hypoxemia when compared to propofol. While the advantages of ciprofol over propofol were primarily limited to reduced injection pain and decreased hypotension during induction, the universal use of ciprofol in overweight and obese patients warrants further exploration in future studies due to its higher cost. However, additional evidence is required to validate these findings due to the limitations posed by the sample size.
Supplementary Information
Acknowledgements
The authors thank all the participants of present study.
Abbreviations
- SpO2
Pulse oxygen saturation
- WHO
World Health Organization
- BMI
Body mass index
- ASA
American Society of Anesthesiologists
- OSAS
Obstructive sleep apnea syndrome
- HR
Heart rate
- SBP
Systolic blood pressure
- DBP
Diastolic blood pressure
- MAP
Mean arterial pressure
- RR
Respiratory rate
- ECG
Electrocardiogram
- IBW
Ideal body weight
- MOAA/S
Modified Observer’s Assessment of Alertness/Sedation
- etCO2
End-tidal carbon dioxide
- IQRs
Interquartile ranges
- CIs
Confidence intervals
- AD
Absolute differences
- RR
Relative risk
- GABAA
γ-aminobutyric acid type A
- LBW
Lean body weight
- CBW
Corrected body weight
- AEs
Adverse events
Authors’ contributions
Jiaxin Chen: Data curation, Formal analysis, Investigation, Methodology, Writing – review & editing, Project administration. Shuhua Zhao: Data curation, Investigation. Lifei Lai: Investigation. Jingling Tian: Investigation. Zhe Zhu: Investigation. Yingqing Deng: Supervision. Qianqian Zhu: Conceptualization, Writing – review & editing, Writing – original draft, Funding acquisition, Project administration, Supervision.
Funding
This study was supported by Funding of Shenzhen Clinical Research Center for Gastroenterology (Gastrointestinal Surgery), Grant No.LCYSSQ20220823091203008.
Data availability
The datasets generated and/or analysed during the current study are not publicly available but are available from the corresponding author on reasonable request.
Declarations
Ethics approval and consent to participate
This study was approved by the Institutional Review Board of the Seventh Affiliated Hospital of Sun Yat-sen University (approval number: KY-2024-082-03).
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.
Jiaxin Chen, Lifei Lai and Shuhua Zhao contributed equally as first author.
Zhe Zhu, Jingling Tian and Qianqian Zhu contributed equally as corresponding author.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Data Availability Statement
The datasets generated and/or analysed during the current study are not publicly available but are available from the corresponding author on reasonable request.