Safety, Pharmacokinetics, and Pharmacodynamics of a Single Bolus of the γ-aminobutyric Acid (GABA) Receptor Potentiator HSK3486 in Healthy Chinese Elderly and Non-elderly

The Median Effective Dose of Ciprofol Combined with Sufentanil for Inhibiting Responses to Gastroscope Insertion in Obese Patients: A Prospective, Single-Center Study

Background

Ciprofol, a recently developed intravenous anesthetic, whereas sufentanil is a widely used adjuvant for gastroenteroscopy sedation. The recommended dosage of ciprofol for obese patients remains unclear. Our study aimed to determine the median effective dose (ED50) of ciprofol in combination with sufentanil for obese patients undergoing gastroscopy sedation.

Methods

A total of 70 patients undergoing painless gastroscopy from July 2024 to September 2024 were recruited. Patients were assigned to the obese group (body mass index [BMI]≥28 kg/m2, n=34) and non-obese group (18.5 kg/m2 ≤BMI<24 kg/m2, n=36). All patients received 0.1 μg/kg of sufentanil, and the ciprofol dose was determined by the modified Dixon sequential method with an initial dose of 0.4 mg/kg and a dose gradient of 0.01 mg/kg. The dose of ciprofol administered to the subsequent patient was determined by the response of the preceding patient. The response referred to the patient's cough, swallowing, and body movement during gastroscope insertion. The primary outcome was the ED50 of ciprofol in each group, while the secondary outcomes comprised the incidences of hypoxemia, hypotension, bradycardia, postoperative nausea and vomiting (PONV), and hemodynamic parameters.

Results

The ED50 of ciprofol was 0.278 mg/kg (95% confidence interval [CI]: 0.226-0.297 mg/kg) in the obese group and 0.347 mg/kg (95% CI: 0.329-0.360 mg/kg) in the non-obese group for gastroscopy sedation. The ED50 of ciprofol in the obese group was significantly lower than that in the non-obese group (P<0.05). The incidence of hypoxemia in the obese group was significantly higher than that in the non-obese group (P<0.05).

Conclusion

Obesity affected the ED50 of ciprofol, suggesting that the ciprofol dosage should be adjusted in obese patients.

Pharmacological mechanism and clinical application of ciprofol

Propofol has become one of the most commonly used anesthetic agents because of its good sedative effects, rapid onset, and fast metabolism. However, its associated respiratory and circulatory depression and injection pain make it difficult for patients to tolerate. Ciprofol, which is structurally similar to propofol but has an additional cyclopropyl group, is less likely to impact respiratory and circulatory function and cause injection pain, highlighting its potential for clinical application. Currently, as research on Ciprofol is still in the exploratory stage, its clinical application is limited because its underlying mechanisms are not yet fully understood. The aim of this article is to review the pharmacological mechanisms of propofol, hypothesize the primary pharmacological effects and potential adverse reactions of Ciprofol, and summarize its current clinical application status, with the goal of providing a reference for future clinical use.

Effects of cipepofol on breathing patterns, respiratory drive, and inspiratory effort in mechanically ventilated patients

Background

Cipepofol is a highly selective gamma-aminobutyric acid A receptor potentiator. As a new sedative drug, detailed studies on its respiratory effects are further needed. The present study aims to investigate the effects of cipepofol on breathing patterns, respiratory drive, and inspiratory effort in mechanically ventilated patients.

Methods

In this one-arm physiological study, cipepofol was initiated at 0.3 mg/kg/h and increased by 0.1 mg/kg/h every 30 min until reaching 0.8 mg/kg/h. Discontinuation criteria were Richmond Agitation and Sedation Scale (RASS) score ≤ -4 or respiratory rate (RR) < 8 breaths/min or pulse oxygen saturation (SpO2) < 90%. The primary outcomes were changes from baseline in respiratory variables [RR, tidal volume (VT), minute ventilation (Vmin), airway occlusion pressure at 100 msec (P0.1), pressure muscle index (PMI), expiratory occlusion pressure (Pocc)] at 30 min after 0.3 mg/kg/h cipepofol infusion. The secondary outcomes included changes in respiratory variables, cardiorespiratory variables, and RASS scores at rates of cipepofol from 0.3 to 0.8 mg/kg/h.

Results

20 patients were enrolled and all of them completed the cipepofol infusion rate at 0.3 mg/kg/h, achieving RASS score of -2 to +1. For the primary outcomes, there was a significant reduction in VT (390.9, [356.6-511.0] vs. 451.6 [393.5-565.9], p = 0.002), while changes in RR (16.7 ± 2.7 vs. 16.2 ± 3.4, p = 0.465) and Vmin (7.2 ± 1.8 vs. 7.5 ± 1.9, p = 0.154) were not significant. The reductions in P0.1 (p = 0.020), PMI (p = 0.019), and Pocc (p = 0.007) were significant. For secondary outcomes, as the infusion rate of cipepofol increased from 0.3 to 0.8 mg/kg/h, there was a further decrease in VT (p = 0.002) and an increase in RR (p < 0.001), while the change in Vmin (p = 0.430) was not significant. RASS score (p < 0.001) was further decreased.

Conclusion

Cipepofol demonstrates the capability to achieve RASS score -2 to +1 in mechanically ventilated adult patients. The effect of cipepofol on breathing patterns was a decrease in VT, while changes in RR and Vmin were insignificant. The effect on respiratory drive and inspiratory effort significantly reduced P0.1, PMI, and Pocc.

Clinical trial registration

ClinicalTrials.gov, identifier NCT06287138. https://clinicaltrials.gov/study/NCT06287138.

Pharmacokinetics and pharmacodynamics of ciprofol after continuous infusion in elderly patients

BACKGROUND

Ciprofol, a novel intravenous anesthetic, which has primarily been used for the induction and maintenance of general anesthesia in adults, is characterized by rapid onset, short duration of action, and quick and smooth recovery. However, the pharmacokinetic characteristics of continuous infusions and the correlation between the plasma concentration and the bispectral index (BIS) in elderly patients are still unknown.

METHOD

In this randomized, controlled study, thirty elderly patients (62-78 years old) undergoing elective gastrointestinal tumor resection were treated with propofol (N = 15) or ciprofol (N = 15) as sedatives during anesthesia. After induction, ciprofol/propofol was continuously infused intravenously until the end of the operation. Perioperative vital signs, injection pain, adverse events (AEs), BIS values, eyelid reflex disappearance times, and recovery times were recorded. The plasma concentrations of ciprofol and propofol were measured by liquid chromatography tandem mass spectrometry (LC‒MS/MS) and the pharmacokinetics were determined by noncompartmental analysis.

RESULTS

Both drugs caused a decrease in blood pressure and heart rate after induction. Eight cases (53. 3%) of hypotension and 3 cases (20%) of bradycardia occurred in the propofol group, while 8 cases (53. 3%) of hypotension and 5 cases (33. 3%) of bradycardia occurred in the ciprofol group. At intubation, the ciprofol group experienced fewer fluctuations in blood pressure than the propofol group. Ciprofol resulted in only one case (6.7%) of mild injection pain, less than that produced by propofol (10/15, 66.7%) (P < 0.05). Anesthesia induction was successfully completed with both drugs, and there were no significant differences in eyelash reflex disappearance or recovery time between the two groups. The plasma concentrations during maintenance were relatively stable in both groups (propofol 1.78 ± 0.67 μg/mL, ciprofol 0.71 ± 0.23 μg/mL), and a suitable depth of sedation was achieved with a BIS of 40-60. The pharmacokinetic (PK) parameters for ciprofol are listed as follows: Maximum Plasma Concentration (Cmax) 6.02 ± 2.13 μg/ml; Time to Maximum Concentration (Tmax) 0.18 ± 0.62 min; Apparent Volume of Distribution (Vz) 3.96 ± 0.84 L/kg; Total Clearance (CL) 0.83 ± 0.14 L/h/kg; Half-life (t½) 3.47 ± 1.85 h; Area Under the Curve (AUC) 5000 ± 900 L/h/kg; Terminal Elimination Rate Constant (λz) 0.23 ± 0.07 1/h. Similar to propofol, the plasma concentration of ciprofol was linearly correlated with the BIS.

CONCLUSION

Ciprofol, a novel intravenous anesthetic, can be safely and effectively used in elderly patient continuous infusion with minimal injection pain. Plasma concentrations of ciprofol correlate well with BIS values, helping control sedation depth. For elderly patients undergoing gastrointestinal tumor surgery, an optimal maintenance dose of 0.8 mg/kg/h is recommended.

TRIAL REGISTRATION

This clinical trial (registration No: ChiCTR2100047580, https://www.chictr.org.cn . The pre-registration date was June 20, 2021, and the review approval and official case solicitation began in December 2021; Retrospectively registered) was conducted in accordance with the World Medical Congress Declaration of Helsinki and Good Clinical Practice guidelines. All study subjects provided written informed consent.

Effect of propofol and ciprofol in patients undergoing bronchoscopy: protocol for a double-blind, randomised controlled trial

INTRODUCTION

Propofol is a fast-acting intravenous anaesthetic widely used for sedation and anaesthesia in gastrointestinal endoscopy, bronchoscopy, and the induction/maintenance of general anaesthesia in outpatients and inpatients; however, propofol has several undesirable effects, including injection pain, which affects the physical and mental health of patients, and cardiopulmonary depression, characterised by hypotension, bradycardia and apnea, which commonly occur in clinical practice. Ciprofol (HSK3486) is a propofol analogue with good clinical safety, high potency and some advantages over propofol, including lower injection pain and haemodynamic depression in patients undergoing gastroscopy and colonoscopy. This study aims to compare the impact of equivalent effective doses of propofol and ciprofol on haemodynamic changes in patients undergoing bronchoscopy under general anaesthesia.

METHODS

This prospective, double-blind, randomised, controlled clinical trial will recruit 250 patients aged 18-80 years scheduled for elective bronchoscopy under general anaesthesia. The cohort will be randomised into two groups in a 1:1 ratio: propofol (200 mg/20 mL of saline) and ciprofol (40 mg/20 mL of saline). The primary outcomes are changes in heart rate and blood pressure before and after induction, laryngeal mask airway (LMA) placement and bronchoscopy placement. The secondary outcomes are the incidence of choking and injection pain, the type and dose of vasoactive drugs used during the operation, and the level of postoperative satisfaction among surgeons, anaesthesiologists and patients.

ETHICS AND DISSEMINATION

This trial was approved by the Medical Ethics Committee of Shanghai Fourth People's Hospital, School of Medicine, Tongji University and registered with the Chinese Clinical Trials Registry (Identifier: ChiCTR2200063048) on 29 August 2022. The findings of this study will be disseminated through various channels. Academic dissemination will include publication in peer-reviewed journals and presentations at national and international conferences.

TRIAL REGISTRATION NUMBER

ChiCTR2200063048.

Effect of different doses of ciprofol on hemodynamics induced by general anesthesia in elderly diabetic patients undergoing spinal surgery: a double-blind, randomized, controlled study

BACKGROUND

To evaluate the safety and efficacy of different doses of ciprofol for the induction of general anesthesia in elderly patients with diabetes undergoing spinal surgery.

METHODS

Ninety elderly diabetic patients scheduled for elective single-level posterior lumbar interbody fusion (PLIF) under general anesthesia were enrolled and randomly assigned to three groups according to the induction dose of ciprofol: group A (0.2 mg/kg), Group B (0.3 mg/kg), and Group C (0.4 mg/kg). The safety and efficacy of anesthesia induction were compared among the three groups.

CASE PRESENTATION

The incidence of hypotension in Group C (46.4%) was significantly higher than that in Groups A (7.4%) and B (14.8%) (P < 0.05). The area under the time-mean arterial pressure curve (AUTMAP) was significantly greater in Group C (176.39 ± 33.83 mmHg·min) than in Group B (158.44 ± 26.55 mmHg·min) and Group A (143.59 ± 19.52 mmHg·min) (P < 0.05). The incidence of intubation response was highest in Group A (77.8%, P < 0.05). Significant differences in bispectral index (BIS) values were observed at 3, 4, and 5 min post-administration among the groups CONCLUSIONS: The induction regimen of 0.3 mg/kg ciprofol combined with 0.4 µg/kg sufentanil and 0.7 mg/kg rocuronium provided superior hemodynamic stability and reduced the need for vasoactive drugs in elderly diabetic patients. This regimen was found to be more favorable compared to the 0.2 mg/kg and 0.4 mg/kg ciprofol dosing groups, demonstrating an optimal balance of safety and efficacy during anesthesia induction in this high-risk population. This trial was registered in the Chinese Clinical Trial Registry on February 26, 2024 (Registration Number: ChiCTR2400081164).

Comparative effective dose of ciprofol and propofol in suppressing cardiovascular responses to tracheal intubation

Ciprofol, a novel γ-aminobutyric acid receptor agonist, outperforms propofol with minimal cardiovascular effects, higher potency, reduced injection pain, and a broader safety margin. Despite these advantages, ciprofol's clinical research is still emerging. This study compares the median effective dose (ED50) and adverse reactions of ciprofol and propofol, in conjunction with sufentanil, for suppressing cardiovascular responses during tracheal intubation. Fifty-three adult patients scheduled for tracheal intubation under general anesthesia were enrolled and randomly assigned to receive either ciprofol (Group C) or propofol (Group P), according to a random number table. Tracheal intubation was performed using a standardized laryngoscope and endotracheal tube. The Dixon's up-and-down method was employed to determine the ED50 and 95% effective dose (ED95) of ciprofol and propofol in inhibiting cardiovascular responses during tracheal intubation. Based on the pilot study, the initial dose for ciprofol was set at 0.35 mg/kg (with a 0.01 mg/kg increment) and for propofol at 2.0 mg/kg (with a 0.1 mg/kg increment). Probit analysis was applied to derive dose-response curves, while adverse reactions were continuously monitored. A total of 54 participants were included, with 24 in group C (1 excluded) and 30 in group P. Probit analysis revealed that the ED50 of ciprofol for inhibiting cardiovascular responses to tracheal intubation were 0.326 mg/kg (95% CI 0.304-0.337 mg/kg), and for propofol, 1.541 mg/kg (95% CI 1.481-1.599 mg/kg). The heart rate in group P was significantly higher than the group C at 1 minute (p = 0.026) and 3 minutes (p = 0.016) post-intubation. Systolic and diastolic blood pressures (SBP and DBP) decreased significantly before and after intubation compared to baseline values in both groups (p< 0.05). Group C experienced significantly less injection pain (p = 0.001), although the incidence of other adverse effects was not statistically different between groups (p > 0.05).Clinical Trial Registration: hppts://ClinicalTrials.gov; Identifier: NCT06095570(18/10/2023).

EC50 and EC95 of Remifentanil for Inhibiting Bronchoscopy Responses in Elderly Patients During Fiberoptic Bronchoscopy Under Ciprofol Sedation: An Up-and-Down Sequential Allocation Trial

Background

Opioids are used to suppress cough during fiberoptic bronchoscopy (FOB). However, evidence regarding the optimal dose of remifentanil during FOB under ciprofol sedation is limited. This study aimed to investigate the effective concentration (EC) of remifentanil required to suppress bronchoscopy responses during FOB under ciprofol sedation in elderly patients.

Materials and Methods

Elderly patients aged 60 to 90 years with American Society of Anesthesiologists (ASA) physical status I-III, scheduled for FOB, were enrolled. Patients were assigned to either the male or the female group. Remifentanil was administered intravenously prior to ciprofol administration. The endpoints included responses to FOB, such as vocal cords movement, coughing, and body movement. The EC50 and EC95 values of remifentanil required to alleviate the responses to FOB were calculated using Dixon's up-and-down method for both male and female groups. Probit analysis was used to generate a dose-response curve.

Results

Thirty-nine patients (19 males and 20 females) were enrolled. The EC50 values (plasma concentration) of remifentanil for blunting FOB responses under ciprofol sedation were 3.25 (2.75 to 3.26) ng/mL and 2.25 (1.75 to 2.25) ng/mL in males and females, respectively (p = 0.0023). Probit analysis indicated that the EC50 of remifentanil required to suppress responses to FOB under ciprofol sedation was 3.102 [95% confidence interval (CI):2.694 to 3.749] ng/mL and 2.052 [95% CI: 1.345 to 2.750] ng/mL in males and females, respectively. The EC95 of remifentanil required to suppress responses to FOB under ciprofol sedation was 3.741 [95% CI: 3.366 to 7.699] ng/mL and 2.943 [95% CI: 2.456 to 9.533] ng/mL in males and females, respectively.

Conclusion

The results indicate differences between males and females in the EC50 and EC95 of remifentanil needed to suppress responses to FOB under ciprofol sedation while preserving spontaneous breathing in elderly patients.

Trial Registration

The study was registered with chictr.org.cn (ChiCTR2300077720; 17 th November 2023).

Comparison of postoperative awakening between ciprofol and propofol in elderly patients undergoing hip replacement surgery: a single-blind, randomized, controlled trial

BACKGROUND

The aim of this paper was to compare the impact of continuous infusion of ciprofol versus propofol on postoperative awakening in elderly patients following hip replacement surgery.

METHODS

Patients were randomized into two groups (N.=45 each): the ciprofol group and the propofol group. The ciprofol group received ciprofol for anesthesia induction and maintenance, while the propofol group underwent anesthesia induction and maintenance using propofol. The primary outcome was awakening time. Secondary outcomes included spontaneous breathing recovery time, extubation time, time to modified Aldrete Score ≥9, modified observer's assessment of alertness/sedation (MOAA/S) scores, anesthetic dosage, volume of fluid replacement, urine output and administration of vasoactive drugs.

RESULTS

The Ciprofol group exhibited a significantly prolonged awakening time (11.0±6.4 min vs. 7.4±4.3 min, P=0.003), spontaneous breathing recovery time (9.9±6.3 min vs. 5.9±4.3 min, P=0.001), and extubation time (12.0 [8.0-16.0] min vs. 8.5 [6.0-11.0] min, P=0.005), and reduced requirement for intraoperative fluid replacement (728.9±254.2 mL vs. 908.3±287.5 mL, P=0.003), increased urine output (235.1±102.1 mL vs. 173.5±106.2 mL, P=0.007), decreased likelihood of vasoactive drug administration (15/30 vs. 28/14, P=0.002). No significant differences were observed between the two groups in terms of reaching a modified Aldrete Score ≥9, MOAA/S scores at 0, 5, 15, or 30 minutes post-extubation, or occurrence of adverse reactions (P>0.05). The dosage of remifentanil was significantly higher in the ciprofol group [5.4 (2.7-7.4) μg·kg-1·h-1 vs. 3.4 (1.9-4.3) μg·kg-1·h-1, P=0.004], with a mean maintenance dose of ciprofol at 0.8 mg·kg-1·h-1 (range: 0.5 to 1.2 mg·kg-1·h-1).

CONCLUSIONS

Compared to propofol, the administration of ciprofol in elderly patients following hip replacement surgery is associated with prolonged awakening time, spontaneous breathing recovery time, and extubation. The average intravenous maintenance dosage of ciprofol in geriatric patients under general anesthesia was 0.8 mg·kg-1·h-1.

Efficacy and Safety of Ciprofol Versus Propofol as Anesthetic for Patients Undergoing Painless Colonoscopy

INTRODUCTION

Ciprofol is a novel propofol analogue with a characteristic of hemodynamic stability. At present, there is a lack of research comparing the hemodynamic stability of ciprofol and propofol during painless colonoscopy. In this study, we aim to test the hypothesis that ciprofol is superior to propofol in terms of hemodynamic stability for sedation anesthesia in patients undergoing colonoscopy.

METHODS

A total of 222 patients were randomized into two groups. Patients in group P (n = 112) and group C (n = 110) received propofol and ciprofol sedation, respectively. Noninvasive blood pressure were monitored starting from induction (T0) to the end of the procedure, at 2-min intervals (T1 to T10). Heart rate variability (HRV), pain injection, Modified Observer's Assessment of Alertness and Sedation (MOAA/S) score, body movement, doses of norepinephrine, modified Aldrete score, drug-related adverse reactions, and patient satisfaction and endoscopist satisfaction were recorded.

RESULTS

In group C, fewer patients experienced a decrease in blood pressure with a higher HRV after induction sedation, the incidence of pain injection was reduced, the amount of norepinephrine dose was decreased, patient satisfaction was increased compared with group P (all P < 0.05). There were no significant differences in induction time, modified Aldrete score, alertness time, drug-related adverse reactions, and endoscopist satisfaction.

CONCLUSIONS

Our study indicated intravenous induction with ciprofol was superior, with regard to hemodynamic stability and reduced injection pain, than induction with propofol for anesthesia in patients undergoing painless colonoscopy.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR2200061814).

The efficacy and safety of ciprofol versus propofol in patients undergoing painless hysteroscopy: a randomized, double-blind, controlled trial

BACKGROUND

Studies have reported that ciprofol has the advantage of reducing injection pain compared to propofol during gastroscopy, colonoscopy, and fiberoptic bronchoscopy. The effect of ciprofol on the injection pain in painless hysteroscopy needs to further explore.

METHODS

A double-blind randomized controlled trial (RCT) was designed, and patients were recruited from the First Central Hospital of Baoding from March 2024 to June 2024. The eligible participants were allocated into ciprofol group (ciprofol combined with alfentanil) and propofol group (propofol combined with alfentanil) at 1:1 ratio. The primary outcome was injection pain. The secondary outcomes included sedation success rate, anesthesia success rate, adverse events, patient satisfaction, and comparison of vital signs before and after administration.

RESULTS

A total of 217 participants were included for analysis, with 109 participants in the ciprofol group and 108 participants in the propofol group. The injection pain rate of ciprofol group (18.35%) was significantly lower than the propofol group (40.74%). Both the ciprofol group and propofol group had 100% of the sedation success rate. The anesthesia success rate between the two groups was comparable (P > 0.05). The rate of adverse events was lower (27.52% vs. 45.37%) and patient satisfaction was higher (9.84 ± 0.45 vs. 9.65 ± 0.85) in the ciprofol group than the propofol group. In addition, values of systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) in propofol group were significantly lower than those in ciprofol group at the time of cervical dilation and consciousness recovery.

CONCLUSIONS

Ciprofol exhibits comparable efficacy to that of propofol, and is associated with less injection pain rate, fewer adverse events, higher patient satisfaction, and more stable hemodynamics when used for general anesthesia during the painless hysteroscopy.

CLINICAL TRIAL NUMBER

NCT06413862.

Bispectral Index-Monitored Anesthesia Induction in Older Adults Undergoing Elective Surgery: Comparing Ciprofol and Propofol in a Prospective, Single-Center, Double-Blind, Randomized Controlled Study

Purpose

Ciprofol, a new sedative anesthetic developed in China, offers rapid onset and recovery, reduced injection pain, and stable circulation. However, its effect on blood pressure during anesthesia induction in older adults remains unclear. To compare the effects of propofol and ciprofol on hypotension induced by general anesthesia in older adults.

Patients and Methods

This prospective, single-center, double-blind, randomized, controlled clinical study enrolled 117 older adults undergoing surgery. Patients in the ciprofol group (group C) received an intravenous injection of ciprofol (0.3 mg/kg, n=57), while the propofol group (group P) received an intravenous injection of propofol (1.5 mg/kg, n=58). The primary outcome was the incidence of hypotension (mean arterial pressure (MAP) decreased by > 30% from baseline or MAP< 65 mmHg). Secondary outcomes included induction success rate (bispectral index (BIS) value ≤60 and Modified Observer's Assessment of Alertness/Sedation Scale (MOAA/S) score ≤1), injection pain, number of drug additions, time to BIS 60, time to eyelash reflex disappearance, blood pressure changes, incidence of hypertension, tachycardia and BIS values before and after administration.

Results

The incidence of induced hypotension was 26.3% (15/57) in group C and 48.3% (28/58) in group P (OR=0.383, 95% CI:175-0.837, P =0.015). Group C had significantly lower injection pain incidence (5.3% vs 20.7%, OR=0.213, 95% CI: 0.057-0.801, p=0.014). Both groups had a 100% induction success rate, with no significant difference in the number of additional doses. Post-intubation hypertension and tachycardia incidence were not significantly different. Group C showed less blood pressure decrease during induction and a deeper anesthesia level.

Conclusion

Compared to propofol, ciprofol reduces the incidence of induced hypotension in older adults and maintains more stable blood pressure during induction. Additionally, ciprofol reduces injection pain and provides a good depth of anesthesia, making it a safe and effective option for anesthesia induction in older adults.

Trial Registration ClinicalTrialsgov Identifier

ChiCTR2200066053.

The efficacy of ciprofol versus propofol on anesthesia in patients undergoing endoscopy: a systematic review and meta-analysis of randomized controlled trials

INTRODUCTION

Ciprofol is a new intravenous anesthetic with a similar chemical structure to propofol. We aimed to compare the incidence of adverse actions like injection pain and time indexes of ciprofol versus propofol on anesthesia in patients undergoing endoscopy. We also compared anesthetists' satisfaction during the procedure.

METHODS

Two independent researchers (Liu and Zeng) searched the Cochrane Library, Embase databases, and PubMed for controlled clinical trials. This meta-analysis of randomized controlled trials (RCTs) was performed with the Review Manager, Stata and the Cochrane Risk-of-Bias 2 tool to evaluate methodological quality. Relative risks with 95% confidence interval (CI) were calculated for outcomes.

RESULTS

Ten trials, including 1545 patients, were examined in the current meta-analysis. During anesthesia in patients undergoing endoscopy, the incidence of injection pain was significantly reduced in the research group. Compared with propofol, the pooled risk difference (RD) with the use of ciprofol for injection pain for all the procedures was - 0.34 (95% confidence interval [CI], -0.48 to 0.19), and RR for hypotension was 0.73(95% CI:0.58 to 0.92). GRADE showed this meta-analysis has moderate or low confidence. Trial sequential analysis for mortality indicated insufficient sample size for a definitive judgment for lower incidence of hypotension.

CONCLUSION

In painless endoscopy, compared with propofol, ciprofol exhibited non-inferiority anesthesia/sedation in patients, and had a good safety profile with a lower incidence of pain on injection and may reduce the chance of hypotension. Trial sequential analysis suggested the need for more cases, and GRADE highlighted moderate certainty, emphasizing the necessity for further targeted RCTs.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42023433627.

Effects of ciprofol infusion on hemodynamics during induction and maintenance of anesthesia and on postoperative recovery in patients undergoing thoracoscopic lobectomy: Study protocol for a randomized, controlled trial

INTRODUCTION

Ciprofol, a new candidate drug, is effective and safe for the maintenance of anesthesia in non-cardiothoracic and non-neurological elective surgery. However, few studies have been conducted on general anesthesia using ciprofol in patients undergoing thoracoscopic lobectomy. Therefore, this study aims to observe the effects of ciprofol on hemodynamics and on postoperative recovery in patients undergoing thoracoscopic lobectomy.

METHODS AND ANALYSIS

This randomized controlled trial will include 136 patients aged 18-65 years undergoing elective thoracoscopic lobectomy between April 2023 and December 2024. The participants will be randomly assigned to the propofol or ciprofol group. The primary outcome to be assessed is the hemodynamic fluctuation during the induction and maintenance of anesthesia. The secondary outcomes involve quality of anesthesia induction and quality of recovery from anesthesia. The former includes TLOC (time to loss of consciousness), the use of vasoactive agents, the incidence of injection pain, body movement, muscle twitching and coughing during induction of anesthesia. The latter includes TROC (time to recovery of consciousness), post anesthesia care unit (PACU) time, incidence of postoperative nausea and vomiting (PONV), postoperative agitation, intraoperative awareness and quality of recovery (QoR) score.

DISCUSSION

A number of clinical trials have confirmed that ciprofol, as a new sedative-hypnotic agent, has advantages of better tolerance, higher sedation satisfaction score, and lower incidence of adverse reactions, especially in reducing the incidence of injection pain. But considering that ciprofol was recently developed, limited data are available regarding its use for general anesthesia. This study aims to investigate the effects of ciprofol on hemodynamics and on postoperative recovery of patients undergoing thoracoscopic lobectomy. The results of this study may provide evidence for the safe application of ciprofol, a new choice of general anesthetic for thoracic surgery.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov (NCT05664386).

Comparison of the efficacy and safety of ciprofol and propofol in sedating patients in the operating room and outside the operating room: a meta-analysis and systematic review

BACKGROUND

As a new type of intravenous anesthetic, ciprofol has the advantages of fast onset of action, fast recovery and high clearance rate. This study aimed to investigate the effectiveness and safety of ciprofol versus traditional propofol for anesthesia and sedation in and out of the operating room.

METHODS

We searched the literature in PubMed, Web of Science, Cochrane Library, and Embase databases from January 2021 to December 2023. All clinical studies comparing the sedative effects of propofol and ciprofol, both inside and outside the operating room, were included in our trial. The main outcome measures were induction time and incidence of injection-site pain. Data are merged using risk ratio and standardized mean difference with 95% confidence interval. Subgroup analysis, meta-regression, sensitivity analysis, and publication bias were performed. The study protocol was prospectively registered with PROSPERO (CRD42023447747).

RESULTS

A total of 15 randomized, controlled trials involving 2002 patients were included in this study. Compared with propofol, ciprofol has a longer induction time in the operating room but a shorter induction time in non-operating room settings. Ciprofol can effectively reduce the risk of injection-site pain and respiratory depression both inside and outside the operating room. In addition, the risk of drug-related hypotension induced with ciprofol in the operating room is lower, but the awakening time is also longer. Meta-regression analysis showed that neither age nor BMI were potential sources of heterogeneity. Funnel plot, egger and begg tests showed no significant publication bias. Sensitivity analyzes indicate that our results are robust and reliable.

CONCLUSION

Ciprofol has absolute advantages in reducing the risk of injection-site pain and respiratory depression, both in and outside operating room. Intraoperative use of ciprofol reduces the risk of drug-related hypotension and may also reduce the risk of intraoperative physical movements. However, ciprofol may have longer induction and awakening time than propofol.

ED50 of ciprofol combined with sufentanil for fiberoptic bronchoscopy of different patient populations with pulmonary tuberculosis

BACKGROUND

Ciprofol is a promising sedative. This study aims to explore the median effective dose (ED50) of ciprofol in inhibiting responses to fiberoptic bronchoscopy in patients with pulmonary tuberculosis (PTB) of different genders and ages when combined with 0.15 μg/kg sufentanil, and to evaluate its efficacy and safety, providing a reference for the rational use of ciprofol in clinical practice.

METHODS

PTB patients who underwent bronchoscopy examination and treatment at The Third People's Hospital of Changzhou between May 2023 and June 2023 were selected and divided into four groups using a stratified random method. All patients received intravenous injection of 0.15 μg/kg sufentanil followed by injection of the test dose of ciprofol according to Dixon's up-and-down method. The initial dose of ciprofol in all four groups was 0.4 mg/kg, with an adjacent ratio of 1:1.1. The next patient received a 10% increase in the dose of ciprofol if the previous patient in the same group experienced positive reactions such as choking cough, frowning, and body movements during the endoscopy. Otherwise, it was judged as a negative reaction, and the next patient received a 10% decrease in the dose of ciprofol. The transition from a positive reaction to a negative reaction was defined as a turning point, and the study of the group was terminated when seven turning points occurred. Hemodynamic parameters, oxygen saturation and adverse reactions were recorded at different time points in all groups. The Probit regression analysis method was used to calculate the ED50 of ciprofol in the four groups and compare between the groups.

RESULTS

The ED50 of ciprofol combined with 0.15 μg/kg sufentanil for bronchoscopy in the four groups were 0.465 mg/kg, 0.433 mg/kg, 0.420 mg/kg and 0.396 mg/kg, respectively.

CONCLUSION

The ED50 of ciprofol used for fiberoptic bronchoscopy varied among PTB patients of different genders and ages.

TRIAL REGISTRATION

The Chinese Clinical Trial Registry, ChiCTR2300071508, Registered on 17 May 2023.

Pharmacokinetics and exposure-safety relationship of ciprofol for sedation in mechanically ventilated patients in the intensive care unit

Ciprofol (HSK3486) is a newly developed, highly selective γ-aminobutyric acid-A (GABAA) receptor potentiator that is recently approved for a new indication of sedation for patients in the intensive care unit (ICU) in China. This analysis aimed to characterize the population pharmacokinetics (PopPKs) of ciprofol and evaluate the relationship of exposure with hypotension in mechanically ventilated patients in the ICU. A total of 462 subjects with 3918 concentration measurements from two clinical trials of mechanically ventilated patients in the ICU, four clinical trials of elective surgical patients, and six clinical trials of healthy subjects were used in the PopPK analysis. Exposure-safety relationship for hypotension was evaluated based on the data gathered from 112 subjects in two clinical trials of mechanically ventilated patients in the ICU. Ciprofol pharmacokinetics (PKs) was adequately described by a three-compartment linear disposition model with first-order elimination. Body weight, age, sex, blood sampling site (vein vs. arterial), study design (long-term infusion vs. short-term infusion), and patient population (ICU vs. non-ICU) were identified as statistically significant covariates on the PKs of ciprofol. Within the exposure range of the mechanically ventilated ICU patient population, no meaningful association was observed between ciprofol exposure and the incidence of hypotension. These results support the dosing regimen currently used in mechanically ventilated patients in the ICU.

Exploring the Median Effective Dose of Ciprofol for Anesthesia Induction in Elderly Patients: Impact of Frailty on ED50

Purpose

Explore the median effective dose of ciprofol for inducing loss of consciousness in elderly patients and investigate how frailty influences the ED50 of ciprofol in elderly patients.

Patients and Methods

A total of 26 non-frail patients and 28 frail patients aged 65-78 years, with BMI ranging from 15 to 28 kg/m2, and classified as ASA grade II or III were selected. Patients were divided into two groups according to frailty: non-frail patients (CFS<4), frail patients (CFS≥4). With an initial dose of 0.3 mg/kg for elderly non-frail patients and 0.25 mg/kg for elderly frail patients, using the up-and-down Dixon method, and the next patient's dose was dependent on the previous patient's response. Demographic information, heart rate (HR), oxygen saturation (SpO2), mean blood pressure (MBP), and bispectral index (BIS) were recorded every 30 seconds, starting from the initiation of drug administration and continuing up to 3 minutes post-administration. Additionally, the total ciprofol dosage during induction, occurrences of hypotension, bradycardia, respiratory depression, and injection pain were recorded.

Results

The calculated ED50 (95% confidence interval [CI]) and ED95 (95% CI) values for ciprofol-induced loss of consciousness were as follows: 0.267 mg/kg (95% CI 0.250-0.284) and 0.301 mg/kg (95% CI 0.284-0.397) for elderly non-frail patients; and 0.263 mg/kg (95% CI 0.244-0.281) and 0.302 mg/kg (95% CI 0.283-0.412) for elderly frail patients. Importantly, no patients reported intravenous injection pain, required treatment for hypotension, or experienced significant bradycardia.

Conclusion

Frailty among elderly patients does not exert a notable impact on the median effective dose of ciprofol for anesthesia induction. Our findings suggest that anesthesiologists may forego the necessity of dosage adjustments when administering ciprofol for anesthesia induction in elderly frail patients.

Comparison of the Efficacy of HSK3486 and Propofol for Induction of General Anesthesia in Adults: A Multicenter, Randomized, Double-blind, Controlled, Phase 3 Noninferiority Trial

BACKGROUND

Propofol is an intravenous anesthetic associated with hypotension, respiratory depression, and injection-site pain. HSK3486 injectable emulsion (ciprofol) is a 2,6-disubstituted phenol derivative with fast onset and quick, stable recovery. Previous studies support HSK3486 as an effective, safe anesthetic with substantially less injection-site pain than propofol. The primary objective of this study was to investigate the noninferiority of HSK3486 compared with propofol in successful general anesthesia induction.

METHODS

Two hundred fifty-five participants were enrolled in HSK3486-304, a multicenter, randomized (2:1), double-blind, propofol-controlled, phase 3 study evaluating HSK3486 for general anesthesia induction in adults undergoing elective surgery with tracheal intubation. The primary endpoint was successful anesthesia induction, defined as 1 or less on the Modified Observer's Assessment of Alertness/Sedation scale. Key secondary endpoints were proportion of participants with injection-site pain on the Numerical Rating Scale of 1 or greater and a composite endpoint, including the proportion of participants successfully induced while maintaining the desired anesthetic depth and without substantial cardiac and respiratory events. Safety endpoints included adverse events, abnormal vital signs, and injection-site pain.

RESULTS

Two hundred fifty-one participants (HSK3486, n = 168; propofol, n = 83) were included in the analyses. General anesthesia was successfully induced in 97.0% versus 97.6% of participants with HSK3486 and propofol, respectively. The difference in success rate was -0.57% (95% CI, -5.4 to 4.2%); the noninferiority boundary of -8% was not crossed. Thirty participants (18.0%) had injection-site pain with HSK3486 versus 64 (77.1%) with propofol (P < 0.0001). Eighty-one participants (48.2%) with HSK3486 versus 42 (50.6%) with propofol (P = 0.8780) satisfied the composite endpoint. When injection-site pain was excluded, the incidence of treatment-emergent adverse events related to study drug was 17.9% for HSK3486 and 14.5% for propofol.

CONCLUSIONS

The study met its primary objective and endpoint, demonstrating noninferiority of HSK3486 compared with propofol in successful anesthetic induction. Substantially less injection-site pain was associated with HSK3486 than with propofol.

EDITOR’S PERSPECTIVE

Efficacy and safety of ciprofol versus propofol for anesthesia induction in adult patients received elective surgeries: a meta‑analysis

BACKGROUND

Propofol is use widely used in anesthesia, known for its effectiveness, may lead to cardiopulmonary issues in some patients. Ciprofol has emerged as a possible alternative to propofol because it can achieve comparable effects to propofol while causing fewer adverse events at lower doses. However, no definitive conclusion has been reached yet. This meta-analysis aimed to evaluate the efficacy and safety of ciprofol versus propofol in adult patients undergoing elective surgeries under general anesthesia.

METHODS

We searched PubMed, EMBASE, the Cochrane library, Web of Science, and Chinese National Knowledge Infrastructure (CNKI) to identify potentially eligible randomized controlled trials (RCT) comparing ciprofol with propofol in general anesthesia until September 30, 2023. The efficacy outcomes encompassed induction success rate, time to onset of successful induction, time to disappearance of eyelash reflex, and overall estimate means in Bispectral Index (BIS). Safety outcomes were assessed through time to full alertness, incidence of hypotension, incidence of arrhythmia, and incidence of injection-site pain. Continuous variables were expressed as mean difference (MD) with 95% confidence interval (CI), and dichotomous variables were expressed as risk ratio (RR) with 95% CI. Statistical analyses were performed using RevMan 5.4 and STATA 14.0. The quality of the evidence was rated through the grading of recommendations, assessment, development and evaluation (GRADE) system.

RESULTS

A total of 712 patients from 6 RCTs were analyzed. Meta-analysis suggested that ciprofol was equivalent to propofol in terms of successful induction rate, time to onset of successful induction, time to disappearance of eyelash reflex, time to full alertness, and incidence of arrhythmia, while ciprofol was better than propofol in overall estimated mean in BIS (MD: -3.79, 95% CI: -4.57 to -3.01, p < 0.001), incidence of hypotension (RR: 0.63, 95% CI: 0.42 to 0.94, p = 0.02), and incidence of injection-site pain (RR: 0.26, 95% CI: 0.14 to 0.47, p < 0.001). All results were supported by moderate to high evidence.

CONCLUSIONS

Ciprofol may be a promising alternative to propofol because it facilitates achieving a satisfactory anesthesia depth and results in fewer hypotension and injection-site pain. However, we still recommend conducting more studies with large-scale studies to validate our findings because only limited data were accumulated in this study.

TRIAL REGISTRATION

PROSPERO 2023 CRD42023479767.

Regioselective 1,2-Alkylboration of Benzylidenecyclopropanes: Access to Csp3-Enriched Cyclopropyl Boronic Esters

We describe a novel, regioselective alkylboration of versatile (hetero)benzylidenecyclopropanes with β-H-containing alkyl iodides and bis(pinacolato)diboron enabled by copper catalysis. This three-component method allows for consecutive B-Csp3 and Csp3-Csp3 bond formation to access Csp3-enriched diverse tertiary cyclopropyl boronic esters with broad functionality tolerance, and the so-formed C-B bond is amenable to further structural diversification. Radical clock experiment, Hammett analysis, and DFT calculation suggest a mechanism of polar, rather than radical manifold, and SN2-type C-C bond formation was found to be the rate-limiting step instead of migratory alkene insertion.

Effective doses of ciprofol combined with alfentanil in inhibiting responses to gastroscope insertion, a prospective, single-arm, single-center study

BACKGROUND

Ciprofol is a novel intravenous sedative and anesthetic. Studies have shown that it features a rapid onset of action, a fast recovery time, slight inhibition of respiratory and cardiovascular functions, and a low incidence of adverse reactions. This study aims to explore the median effective dose (ED50) and the 95% effective dose (ED95) of ciprofol in inhibiting responses to gastroscope insertion when combined with a low dose of alfentanil, and to evaluate its safety, to provide a reference for the rational use of ciprofol in clinical practices.

METHODS

We included 25 patients aged 18-64 years of either sex who underwent gastroscopy under intravenous general anesthesia, with a Body Mass Index (BMI) 18-28 kg/m2, and an American Society of Anesthesiologists (ASA) grade I or II. In this study, the dose-finding strategy of ciprofol followed a modified Dixon's up-and-down method with an initial dose of 0.30 mg/kg and an increment of 0.02 mg/kg. Ciprofol was administered after intravenous injection of 7 µg/kg of alfentanil, and 2 min later a gastroscope was inserted. When the insertion response of one participant was positive (including body movement, coughing, and eye opening), an escalation of 0.02 mg/kg would be given to the next participant; otherwise, a de-escalation of 0.02 mg/kg would be administered. The study was terminated when negative response and positive response alternated 8 times. A Probit model was used to calculate the ED50 and ED95 of ciprofol in inhibiting responses to gastroscope insertion when combined with alfentanil. Patients' recovery time, discharge time, vital signs and occurrence of adverse reactions were recorded.

RESULTS

The ED50 of single-dose intravenous ciprofol injection with 7 µg/kg of alfentanil in inhibiting gastroscope insertion responses was 0.217 mg/kg, and the ED95 was 0.247 mg/kg. Patients' recovery time and discharge time were 11.04 ± 1.49 min and 9.64 ± 2.38 min, respectively. The overall incidence of adverse reactions was 12%.

CONCLUSION

The ED50 of ciprofol combined with 7 µg/kg of alfentanil in inhibiting gastroscope insertion responses was 0.217 mg/kg, and the ED95 was 0.247 mg/kg. Ciprofol showed a low incidence of anesthesia-related adverse events.

TRIAL REGISTRATION

http://www.chictr.org.cn (ChiCTR2200061727).

The optimal induction dose of ciprofol combined with low-dose rocuronium in children undergoing daytime adenotonsillectomy

Adenotonsillectomy is the most common daytime surgery performed on children. Anesthesiologists must select the optimal combination of drugs to ensure effective anesthesia effect and prompt recovery in children. The optimal induction dose of ciprofol in children is unclear. In this study, we aim to investigate the effect of different doses of ciprofol on anesthesia induction in children undergoing daytime adenotonsillectomy and provide a reference for clinical use. 144 children aged 3-12 years, ASA I-II, undergoing daytime adenotonsillectomy, were included in this clinical trial. The children were randomly divided into three groups and given 0.4 mg/kg (C4), 0.6 mg/kg (C6), or 0.8 mg/kg (C8) of ciprofol for anesthesia induction. The primary outcome was intubation conditions. Vital signs and injection pain were also recorded. The rates of unacceptable intubation conditions were 30.6%, 8.7%, and 8.2% in the C4, C6, and C8 groups (P value < 0.0167). The overall incidence of reported injection pain was 3.5%. The heart rate and mean arterial pressure did not differ between the groups at the same time points. We found that combining 0.6 mg/kg of ciprofol with low-dose rocuronium could provide optimal intubation conditions in pediatric daytime adenotonsillectomy patients. This combination resulted in stable circulation and BIS values. This study is registered at the Chinese Clinical Trial Registry (Registration number: ChiCTR2200063144, Date of Registration: 31/08/2022).

Drug-drug interaction of ciprofol injectable emulsion with mefenamic acid capsules in healthy subjects

AIMS

To investigate the drug-drug interaction (DDI) of ciprofol injectable emulsion and mefenamic acid capsules in healthy subjects.

METHODS

Twenty healthy subjects were enrolled in this single-centre, open-label, two-period DDI study. Ciprofol (0.4 mg kg-1 ) was administered as a single dose on days 1 and 5. A 500-mg oral loading dose of mefenamic acid was given on day 4 followed by a 250-mg maintenance dose every 6 h (a total of eight doses). Blood samples for pharmacokinetic analyses were collected. Depth of anaesthesia was monitored using the Modified Observer's Assessment of Alertness and Sedation (MOAA/S) scale and Bispectral Index scores (BISs).

RESULTS

Compared with administration of ciprofol alone, administration with mefenamic acid showed no significant difference in exposure. The geometric mean ratios (GMRs) and their 90% confidence intervals (CIs) for maximum plasma concentration (Cmax ), area under the plasma concentration-time curve calculated from 0 to the last measurement point (AUC0-last ) and AUC to infinity (AUC0-inf ) were 91.6% (86.5-96.9%), 103.3% (100.3-106.4%) and 107.0% (101.2-113.2%), respectively. The MOAA/S and BIS curves for the two treatment periods essentially coincided, indicating that the anaesthesia effect of ciprofol was not affected by mefenamic acid. Seven subjects (35%) reported eight adverse events (AEs) when ciprorol was administered alone and 12 subjects (60%) reported 18 AEs when ciprofol was administered in combination with mefenamic acid. All AEs were mild.

CONCLUSIONS

Mefenamic acid, a UGT1A9 inhibitor, had no significant effect on the pharmacokinetics and pharmacodynamics of ciprofol in healthy subjects. Ciprofol was safe and well tolerated when administered with mefenamic acid.

Efficacy and safety of ciprofol vs. propofol for the induction and maintenance of general anaesthesia: A multicentre, single-blind, randomised, parallel-group, phase 3 clinical trial

BACKGROUND

HSK3486 (ciprofol) is a 2,6-disubstituted phenol derivative that acts like propofol as an agonist at the gamma-aminobutyric acid-A (GABA A ) receptor.

OBJECTIVE

To investigate the efficacy and safety of HSK3486 for general anaesthesia induction and maintenance.

DESIGN

A single-blinded, randomised, parallel-group, phase 3 trial.

SETTING

Involving 10 study centres, from November 24, 2020 to January 25, 2021.

PATIENTS

A total of 129 patients undergoing nonemergency, noncardiothoracic, and nonneurosurgical elective surgery.

INTERVENTION

Patients were randomly assigned at a 2:1 ratio into HSK3486 or propofol groups, to receive HSK3486 (0.4 mg kg -1 ) or propofol (2.0 mg kg -1 ) for induction before a maintenance infusion at initial rates of 0.8 and 5.0 mg kg -1 h -1 , and were adjusted to maintain a bispectral index (BIS) of 40-60 until the end of surgery.

MAIN OUTCOME MEASURES

Noninferiority between the drugs was evaluated as the lower limit of the 95% confidence interval (CI) for the between-group difference in the success rate of anesthetic maintenance (primary outcome) >-8%. Secondary outcomes included successful anaesthetic induction, full alertness and spontaneous breathing recovery, time until leaving the postanaesthesia care unit and changes in BIS. Safety profiles were also measured.

RESULTS

Of 129 enrolled patients, 128 completed the trial, with 86 in the HSK3486 group and 42 in the propofol group. The success rate for the maintenance of general anaesthesia was 100% for both groups, and noninferiority of HSK3486 was confirmed (95% CI -4.28% to 8.38%). No significant differences were found between the two groups of patients with regard to secondary outcomes (all P  > 0.05). There appeared to be a comparable incidence of treatment for emergency adverse events (TEAEs) (80.2% vs. 81.0%, P  = 1.000) and drug-related TEAEs (57.0% vs. 64.3%, P  = 0.451) in the HSK3486 and propofol groups.

CONCLUSION

HSK3486 had a noninferior efficacy profile compared to propofol, exhibiting excellent tolerance.

TRIAL REGISTRATION

Clinicaltrials.gov, identifier: NCT04511728.

Protective effects of combined treatment with ciprofol and mild therapeutic hypothermia during cerebral ischemia-reperfusion injury

Despite improvement in cardiopulmonary resuscitation (CPR) performance, cardiac arrest (CA) is still associated with poor prognosis. The high mortality rate is due to multi-organ dysfunction caused by cerebral ischemia and reperfusion injury (I/R). The guidelines for CPR suggest the use of therapeutic hypothermia (TH) as an effective treatment to decrease mortality and the only approach confirmed to reduce I/R injury. During TH, sedative agents (propofol) and analgesia agents (fentanyl) are commonly used to prevent shiver and pain. However, propofol has been associated with a number of serious adverse effects such as metabolic acidosis, cardiac asystole, myocardial failure, and death. In addition, mild TH alters the pharmacokinetics of agents (propofol and fentanyl) and reduces their systemic clearance. For CA patients undergoing TH, propofol can be overdosed, leading to delayed awakening, prolonged mechanical ventilation, and other subsequent complications. Ciprofol (HSK3486) is a novel anesthetic agent that is convenient and easy to administer intravenously outside the operating room. Ciprofol is rapidly metabolized and accumulates at low concentrations after continuous infusion in a stable circulatory system compared to propofol. Therefore, we hypothesized that treatment with HSK3486 and mild TH after CA could protect the brain and other organs.

Ciprofol: A Novel Alternative to Propofol in Clinical Intravenous Anesthesia?

Ciprofol is a novel compound that was independently developed in China. According to the Chinese product instructions approved by the China National Medical Products Administration and the information of official website, indications for ciprofol include sedation and anesthesia during the surgical/procedure of nontracheal intubation, induction and maintenance of general anesthesia, and sedation during intensive care. Ciprofol is a short-acting intravenous sedative based on the structural modification of propofol. Ciprofol has high efficacy, good selectivity, and fewer adverse reactions, indicating good clinical application potential. A series of clinical studies have been conducted to evaluate the sedative effect of ciprofol in various procedures and settings, including gastroscopy and colonoscopy, fiber-optic bronchoscopy, general anesthesia in elective surgeries, and mechanical ventilation in intensive care units. This review summarizes the chemical structure, pharmacodynamics, and pharmacokinetic properties of ciprofol. We also assessed the efficacy and safety of ciprofol by synthesizing the relevant clinical trial data.

Efficacy and safety of ciprofol-remifentanil versus propofol-remifentanil during fiberoptic bronchoscopy: A prospective, randomized, double-blind, non-inferiority trial

Objective: Ciprofol is a novel 2,6-disubstituted phenol derivative that has improved pharmacokinetic and pharmacodynamic properties compared with propofol. This study was conducted to compare the efficacy and safety of ciprofol-remifentanil versus propofol-remifentanil for patients undergoing fiberoptic bronchoscopy. Methods: Overall, 92 patients undergoing fiberoptic bronchoscopy were included in this prospective, randomized, double-blind, non-inferiority trial and were equally divided into two groups (n = 46 each). Fentanyl (50 μg) was given 2 min before the intravenous infusion of 0.3 mg/kg of ciprofol or 1.2 mg/kg of propofol over a time period of 30 s. During anesthesia maintenance, 0.05-0.2 μg/kg/min of remifentanil combined with one-third to one-fourth of the initial dose of ciprofol or propofol was repeated at 2-min intervals, as required, to maintain a Modified Observer's Assessment of Alertness and Sedation (MOAA/S) scale score <3. The primary outcome was the successful rate of fiberoptic bronchoscopy. Secondary outcomes included demographic characteristics, time metrics, hemodynamics, coughing severity, intubating conditions, lowest oxygen saturation, utilization of study drug doses, number of remedies (lidocaine and vasoactive drugs) used, satisfaction scores of both patients and the endoscopist, occurrence of intraoperative awareness, patients' willing to repeat fiberoptic bronchoscopy, and occurrence and severity of adverse events. Results: The successful completion rate of fiberoptic bronchoscopy was 91.30% (42 of 46; 95% confidence interval [CI]: 82.80%-99.80%) in the ciprofol-remifentanil group and 89.13% (41 of 46; 95% CI: 79.80%-98.50%) in the propofol-remifentanil group. Though the clinically acceptable intubating condition was improved in the ciprofol-remifentanil group, this difference has no clinical statistical difference (p > 0.05). No significant differences were noted between the two groups with respect to time metrics, consumption of fentanyl and remifentanil, or number of remedies (lidocaine and vasoactive drugs). Patients' willingness to repeat fiberoptic bronchoscopy and the satisfaction of both patients and endoscopist were significantly higher in the ciprofol-remifentanil than in the propofol-remifentanil group (p < 0.05). Compared with patients in the propofol-remifentanil group, patients in the ciprofol-remifentanil group had more stable hemodynamics. The lowest oxygen saturation was significantly higher in the ciprofol-remifentanil than in the propofol-remifentanil group (p < 0.05). The numbers of patients who experienced pain on injection in the ciprofol-remifentanil group was significantly lower than the number in the propofol-remifentanil group (p < 0.01). Severity of coughing, clinically acceptable severity of coughing, incidence of intraoperative awareness, and other adverse events were all similar between the two groups (p > 0.05). Only four patients experienced grade 2 adverse events (severe hypotension in one patient in the ciprofol-remifentanil group and three patients in the propofol-remifentanil group; p > 0.05); they were treated with noradrenaline. Conclusion: Ciprofol-remifentanil was non-inferior to propofol-remifentanil with regard to successful sedation for flexible bronchoscopy, when used with pre-intravenous administration of 50 μg of fentanyl. At the same time, patients' willingness to repeat flexible bronchoscopy and the satisfactions were all significantly improved.

Safety, pharmacokinetics and pharmacodynamics of a novel γ-aminobutyric acid (GABA) receptor potentiator, HSK3486, in Chinese patients with hepatic impairment

BACKGROUND

The primary objective of this study was to investigate if hepatic impairment alters the safety, pharmacokinetics, and pharmacodynamics of HSK3486.

RESEARCH DESIGN AND METHODS

This was a clinical trial of HSK3486 in subjects with normal hepatic function (n = 8), and mild (Child-Pugh A; n = 8), or moderate (Child-Pugh B; n = 8) hepatic impairment. Each subject received an IV bolus dose of 0.4 mg/kg HSK3486 for 1 min, immediately followed by a maintenance infusion of 0.4 mg/kg/h HSK3486 for 30 min.

RESULTS

In total, 24 subjects were enrolled and completed the study. HSK3486 was generally well tolerated by all subjects. There were no serious AEs and no deaths reported during the study. The incidence of AEs was numerically highest in subjects with moderate hepatic impairment. The exposure (AUC) of HSK3486 increased gradually with the decrease in hepatic function; however, degree of hepatic impairment had little effect on HSK3486 PD (MOAA/S and BIS).

CONCLUSIONS

Overall, there were no clinically relevant differences in HSK3486 exposure or PD in subjects with mild or moderate hepatic impairment compared to normal control. These data imply that HSK3486 dose adjustment is not warranted in subjects with mild or moderate hepatic impairment.

TRIAL REGISTRATION

The trial is registered at ClinicalTrials.gov (CT.gov identifier: NCT04145596).Key MessageHSK3486 at an IV bolus dose of 0.4 mg/kg and a maintenance infusion of 0.4 mg/kg/h was safe and well tolerated by all mild or moderate hepatic impairment subjects and normal hepatic function subjects.There were no clinically relevant differences in HSK3486 exposure or PD in subjects with mild or moderate hepatic impairment compared to subjects with normal hepatic function.HSK3486 dose adjustment is not required in subjects with mild or moderate hepatic impairment.

The efficacy and safety of ciprofol use for the induction of general anesthesia in patients undergoing gynecological surgery: a prospective randomized controlled study

Background

Ciprofol is a recently developed, short-acting γ-aminobutyric acid receptor agonist sedative that is more potent than propofol, but there have been few clinical studies of this agent to date. Here, we sought to examine the safety and efficacy of ciprofol use for the induction of general anesthesia in individuals undergoing gynecological surgery.

Methods

Women between the ages of 18 and 60 years (ASA physical status 1 or 2) who were scheduled to undergo elective gynecological surgery under general anesthesia were randomly assigned to two equally sized groups in which anesthesia induction was performed using either ciprofol or propofol. General anesthesia induction success rates were the primary outcome for this study, while secondary outcomes included changes in BIS during the 10 min following the first administration of the study drug, the duration of successful induction, and adverse event incidence.

Results

A total of 120 women were included in the study. A 100% rate of successful induction was achieved in both the ciprofol and propofol groups, with no significant differences between these groups with respect to the duration of successful induction (34.8 ± 15.5 s vs 35.4 ± 9.5 s, P = 0.832), the time to the disappearance of the eyelash reflex (33.7 ± 10.6 s vs 34.0 ± 6.5 s, P = 0.860), or tracheal intubation (58.2 ± 31.1 s vs 53.9 ± 25.4 s, P = 0.448). Adverse event rates, including intubation responses, were significantly lower in the ciprofol group as compared to the propofol group(20% vs 48.33%, P = 0.0019). Ciprofol was associated with reduced injection pain relative to propofol (16.7% vs 58.3%, P < 0.001).

Conclusions

Ciprofol exhibits comparable efficacy to that of propofol when used for the induction of general anesthesia in individuals undergoing gynecological surgery and is associated with fewer adverse events.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-022-01782-7.

Esketamine as an Adjuvant to Ciprofol or Propofol Sedation for Same-Day Bidirectional Endoscopy: Protocol for a Randomized, Double-Blind, Controlled Trial With Factorial Design

Background: Same-day esophagogastroduodenoscopy and colonoscopy procedures under sedation have been increasingly performed. This study aims to assess the effects of esketamine combined with ciprofol (a novel anesthetic/sedative agent) or propofol on respiratory and hemodynamic adverse events in patients undergoing same-day bidirectional endoscopy.

Methods: This is a prospective, randomized, double-blind, placebo-controlled, 2 × 2 factorial trial. A total of 180 adult patients scheduled for same-day bidirectional endoscopy under sedation will be randomized, in a 1:1:1:1 ratio, to receive 1 of 4 sedation regimens: 1) ciprofol and esketamine, 2) propofol and esketamine, 3) ciprofol and normal saline placebo, or 4) propofol and normal saline placebo. The primary outcome is a composite of desaturation [peripheral oxygen saturation (SpO₂) < 95%] and hypotension [mean blood pressure (MBP) < 65 mmHg or decrease in MBP ≥20% of baseline] during the sedation and in the recovery room. Secondary outcomes include episodes of desaturation, severe desaturation (SpO₂ < 90%), hypotension, severe hypotension (decrease in MBP ≥30% of baseline), bradycardia, postoperative nausea and vomiting, dizziness or headache, hallucination or nightmare, injection pain, pain scores and fatigue scores, endoscopist satisfaction, and patient satisfaction. Data will be analyzed on the modified intention-to-treat basis.

Discussion: We hypothesize that esketamine as an adjuvant to ciprofol or propofol sedation would improve cardiorespiratory stability. In addition, the potential interactions between interventions will be explored using the factorial design. The results of this trial will provide evidence for daily practice of sedation regimens for same-day bidirectional endoscopy.

Clinical Trial Registration: Chinese Clinical Trials Registry, Identifier ChiCTR2100052523.