Propofol has been widely used in bidirectional gastrointestinal endoscopy sedation; however, it frequently leads to cardiovascular adverse events and respiratory depression. Propofol target-controlled infusion (TCI) can provide safe sedation but may require higher dosages of propofol. On the contrary, etomidate offers hemodynamic stability.

To evaluate the effect of different dose etomidate added to propofol TCI sedation during same-visit bidirectional endoscopy.

A total of 330 patients from Fujian Provincial Hospital were randomly divided into three groups: P, 0.1EP, and 0.15EP. Patients in the P group received propofol TCI only, with an initial effect-site concentration of the propofol TCI system of 3.0 mg/mL. Patients in the 0.1EP and 0.15EP groups received 0.1 and 0.15 mg/kg etomidate intravenous injection, respectively, followed by propofol TCI.

Patients in the 0.15EP group had higher mean blood pressure after induction than the other groups (P group: 78 mmHg, 0.1EP group: 82 mmHg, 0.15EP group: 88 mmHg; P < 0.05). Total doses of propofol consumption significantly decreased in the 0.15EP group compared with that in the other groups (P group: 260.6 mg, 0.1EP group: 228.1 mg, 0.15EP group: 201.2 mg; P < 0.05). The induction time was longer in the P group than in the other groups (P group: 1.9 ± 0.7 minutes, 0.1EP group: 1.2 ± 0.4 minutes, 0.15EP group: 1.1 ± 0.3 minutes; P < 0.01). The recovery time was shorter in the 0.15EP group than in the other groups (P group: 4.8 ± 2.1 minutes, 0.1EP group: 4.5 ± 1.6 minutes, 0.15EP group: 3.9 ± 1.4 minutes; P < 0.01). The incidence of hypotension (P group: 36.4%, 0.1EP group: 29.1%, 0.15EP group: 11.8%; P < 0.01) and injection pain was lower in the 0.15EP group than in the other groups (P < 0.05). Furthermore, the incidence of respiratory depression was lower in the 0.15EP group than in the P group (P < 0.05). Additionally, the satisfaction of the patient, endoscopist, and anesthesiologist was higher in the 0.15EP group than in the other groups (P < 0.05).

Our findings suggest that 0.15 mg/kg etomidate plus propofol TCI can significantly reduce propofol consumption, which is followed by fewer cardiovascular adverse events and respiratory depression, along with higher patient, endoscopist, and anesthesiologist satisfaction.

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.

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.

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.

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.

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

Remimazolam tosilate (RT) is a new, ultrashort-acting benzodiazepine. Here, we investigated the efficacy and safety of RT for general anesthesia in patients undergoing Laparoscopic Cholecystectomy (LC).

In this study, 122 patients undergoing laparoscopic cholecystectomy were randomly allocated to receive either remimazolam tosilate (Group RT) or propofol group (Group P). RT was administered as a slow bolus of 0.3 mg kg- 1 for induction, followed by 1.0-2.0 mg kg- 1 h- 1 for maintenance of general anesthesia. Propofol was started at 2 mg kg- 1 and followed by 4-10 mg kg- 1 h- 1 until the end of surgery. The primary outcome was the time to bispectral index (BIS) ≤ 60. The secondary outcome included the time to loss of consciousness (LoC), and the time to extubation. Adverse events were also assessed.

A total of 112 patients were recruited for study participation. Among them, the time to BIS ≤ 60 in Group RT was longer than that in Group P (Group RT: 89.3 ± 10.7 s; Group P: 85.9 ± 9.7 s, P > 0.05). While the time to LoC comparing remimazolam and propofol showed no statistical significance (Group RT: 74.4 ± 10.3 s; Group P: 74.7 ± 9.3 s, P > 0.05). The time to extubation in Group RT was significantly longer than that in Group P (Group RT: 16.0 ± 2.6 min; Group P: 8.8 ± 4.3 min, P < 0.001). Remimazolam tosilate had more stable hemodynamics and a lower incidence of hypotension during general anesthesia.

Remimazolam tosilate can be safely and effectively used for general anesthesia in patients undergoing Laparoscopic Cholecystectomy. It maintains stable hemodynamics during induction and maintenance of general anesthesia compared with propofol. Further studies are needed to validate the findings.

Chictr.org.cn ChiCTR2300071256 (date of registration: 09/05/2023).

Remimazolam is a novel ultra-short-acting benzodiazepine sedative that acts on the gamma-aminobutyric acid type A receptor (GABAAR).

To compare the efficacies of remimazolam (RMZ), and propofol (PROP) combined with remifentanil and cisatracurium for total intravenous anaesthesia (TIVA) in patients undergoing urological surgery.

A prospective, single-blind, randomised, noninferiority clinical trial.

Single centre from 1 January 2022 to 30 March 2022.

A total of 146 adult patients undergoing elective urological surgery.

Patients were randomly allocated in a 1 : 1 ratio to the PROP or RMZ groups. In the PROP group, anaesthesia was induced with propofol at 100 mg min -1 to reach a bispectral index score (BIS) of 40 to 60. After loss of consciousness (LOC), intravenous fentanyl 3 μg kg -1 was administered, followed by cisatracurium 0.3 mg kg -1 . Patients were intubated 3 min after cisatracurium administration. Anaesthesia was maintained with the combination of propofol (plasma concentration: 2.5 to 4 μg ml -1 ) and remifentanil (plasma concentration: 2.5 to 4 ng ml -1 ). In the RMZ group, anaesthesia was induced with remimazolam tosilate starting at 10 mg kg -1  h -1 to reach a BIS of 40 to 60 and maintained between 0.2 and 2 mg kg -1  h -1 . After LOC, fentanyl and cisatracurium were administered and intubation was performed as in the PROP group. Anaesthesia was maintained with a combination of remimazolam (0.2 to 2 mg kg -1  h -1 ) and remifentanil (plasma concentration: 2.5 to 4 ng ml -1 ).

The primary outcome was the TIVA success rate. The predefined noninferiority margin considered an absolute difference of 6% in the primary outcome between the groups. The secondary outcomes were vital signs, anaesthesia and surgery characteristics, and adverse events.

All patients completed the trial. The success rates of TIVA with remimazolam and propofol were 100 and 98.6%, respectively. The incidence of hypotension during anaesthesia was lower in the RMZ group (26%) than in the PROP group (46.6%) ( P  = 0.016). The median [IQR] total consumption of ephedrine during anaesthesia was higher in the PROP group 10 [0 to 12.5] mg than in the RMZ group 0 [0 to 10] mg ( P  = 0.0002). The incidence of injection pain was significantly higher in the PROP group (76.7%) than in the RMZ group (0; P  < 0.001). No significant differences in the controllability of the anaesthesia depth, anaesthesia and surgery characteristics, or vital signs were observed between the groups.

Remimazolam demonstrated noninferior efficacy to propofol combined with remifentanil and cisatracurium for TIVA in patients undergoing urological surgery.

Chictr.org.cn, identifier: ChiCTR2100050923.

The study was registered in the Chinese Clinical Trial Registry (ChiCTR2100050923, Principal investigator: Xuehai Guan, Date of registration: 8 November 2021, https://www.chictr.org.cn/showproj.html?proj=133466 ).