Evaluating efficacy and safety of sub-anesthetic dose esketamine as an adjuvant to propofol/remifentanil analgosedation and spontaneous respiration for children flexible fibreoptic bronchoscopy: a prospective, double-blinded, randomized, and placebo-controlled clinical trial

Effective doses of remimazolam and esketamine combined with remifentanil for endotracheal intubation without muscle relaxants in pediatric patients

Introduction

The combination of remimazolam and esketamine effectively alleviates adverse hemodynamic effects, such as tachycardia and hypertension, during intubation. However, the dosage for achieving optimal intubation conditions when co-administered with remifentanil remains unestablished. Therefore, this study aimed to determine the effective doses of remimazolam and esketamine for endotracheal intubation without muscle relaxants in pediatric patients using Dixon's up-and-down method.

Methods

This prospective, non-controlled, non-randomized clinical trial sequentially allocated 41 children aged 3-6 into two phases. All patients underwent tracheal intubation under general anesthesia. Patients received a fixed dose of remifentanil at 2.5 μg/kg via a pump over 90 s. In the first phase, the induction dose of remimazolam was set at 0.2 mg/kg. The first patient received esketamine at a dose of 0.5 mg/kg, administered with a dose gradient of 0.2 mg/kg based on Dixon's up-and-down method. 50% effective dose (ED50) and 95% effective dose (ED95) for esketamine were then measured through probit regression analysis. Similarly, in the second phase, the ED95 of esketamine was fixed. The first patient received remimazolam at a dose of 0.2 mg/kg, administered at a dose gradient of 0.1 mg/kg. ED50 and ED95 for remimazolam were then measured. Intubation conditions were assessed via the Copenhagen scale. Heart rate (HR) and mean arterial pressure (MAP) were recorded at the following time points: Just before intubation (T1) and 1 min after intubation (T2). Adverse events were also recorded during anesthesia induction.

Results

At a fixed dose of remifentanil (2.5 μg/kg), the ED50 of esketamine was 0.74 mg/kg (95% confidence interval [CI]: 0.61-0.89 mg/kg), while the ED95 was 0.97 mg/kg (95% CI: 0.85-1.75 mg/kg). The ED50 of remimazolam was 0.39 mg/kg (95% CI: 0.29-0.53 mg/kg), while the ED95 was 0.56 mg/kg (95% CI: 0.46-1.47 mg/kg). Hemodynamic stability was maintained during anesthesia induction, with no significant adverse events observed.

Conclusion

The ED50 and ED95 values of remimazolam and esketamine in this study provide initial dosing references for pediatric endotracheal intubation without muscle relaxants. A fixed dose of 2.5 μg/kg remifentanil combined with these agents is safe and effective in children aged 3-6 years, though further multicenter studies are recommended for validation.

Clinical trial registration

www.chictr.org.cn, number: ChiCTR2200063847.

Prevention of sufentanil-induced cough during induction of general anesthesia by low-dose esketamine

BACKGROUND

Sufentanil is commonly used to induce general anaesthesia due to its rapid onset of action, strong analgesic effect, long-lasting effect, and stable haemodynamics; however, it often induces cough, increasing the risk of anaesthesia. This study aimed to investigate the preventive effect of low-dose esketamine on sufentanil-induced cough.

METHODS

This randomised, double-blind, placebo-controlled clinical study was conducted at the Air Force Medical Center between September 2023 and May 2024. A total of 100 adult patients (ASA of Anaesthesiologists class I-II) required general anaesthesia for elective surgery. The patients were randomly assigned to two groups: the esketamine group (Group E, n = 50), receiving 0.2 mg/kg esketamine intravenously, and the control group (Group C, n = 50), receiving an equal volume of normal saline. The incidence and severity of sufentanil-induced cough were assessed 1 min after administering of 0.5 μg/kg sufentanil intravenously. Heart rate (HR), mean arterial pressure (MAP), and adverse reactions were recorded at four time points: before esketamine administration (T0), 3 min after esketamine administration (T1), 1 min after endotracheal intubation (T2), and 3 min after endotracheal intubation (T3). The results were analyzed using appropriate statistical methods.

RESULTS

A total of 100 eligible patients were screened, of which 99 participated in this study (1 patient refused to participate), 50 in Group E, and 49 in Group C. The incidence of cough in Group E (6.0%) was significantly lower than that in Group C (34.7%) (P < 0.001), and the severity of cough was also significantly milder than that in Group C (P = 0.038). The differences in the HR and MAP levels at T0, T1, T2, and T3 between the two groups were not statistically significant (P > 0.05). Two patients in Group C experienced chest wall stiffness, while no adverse reactions were observed in Group E. The difference in the incidence of adverse reactions between the two groups was not statistically significant (P > 0.05).

CONCLUSION

Low-dose esketamine (0.2 mg/kg) can significantly reduce the incidence of sufentanil-induced cough during the induction of general anaesthesia in patients, with a small impact on haemodynamics, no adverse reactions, and good safety.

A meta-analysis and systematic review based on perioperative management of elderly patients: is ciprofol an alternative to propofol?

PURPOSE

With the rising number of elderly surgical patients, selecting an appropriate anesthetic tailored to their specific needs is essential. Ciprofol, a novel intravenous anesthetic, has garnered attention due to its low injection pain rate and minimal impact on the circulatory system. This meta-analysis aims to examine the efficacy and safety profile of ciprofol during perioperative management of elderly patients.

METHODS

Comprehensive searches of PubMed, Embase, Cochrane, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang, and VIP databases from inception to March 23, 2024, were conducted. Eligible studies were included, data extracted, quality assessed using the ROB2 tool, and analyses performed with Stata 17.0.

RESULTS

Analysis of eleven randomized controlled trials (RCTs) comprising 1715 patients demonstrated that ciprofol outperformed propofol regarding injection pain (RR: 0.13, 95% CI: 0.09-0.20, p < 0.001), hypotension (RR: 0.72; 95% CI: 0.56-0.94; p = 0.014), bradycardia (RR: 0.64, 95% CI: 0.48-0.85, p = 0.002), respiratory depression (RR: 0.29, 95% CI: 0.19-0.43, p < 0.001), hypoxemia (RR: 0.38, 95% CI: 0.26-0.55, p < 0.001), and body movement (RR: 0.73, 95% CI: 0.56-0.96, p = 0.022). No significant differences were observed in induction time(SMD: 0.11,95% CI: -0.39-0.61, p = 0.655), sedative success rate(RR:1.01,,:95% CI:0.97-1.06, p = 0.669)), time of leaving the operating room(SMD-0.21,95% CI: -0.83-0.40, p = 0.497), bucking(RR:0.56,:95% CI:0.27-1.17, p = 0.134)), nausea and vomiting(RR:0.69,95% CI:0.43-1.11, p = 0.143)).

CONCLUSION

Ciprofol demonstrates comparable efficacy to propofol in general anesthesia for elderly patients, with an enhanced safety profile, making it a viable clinical alternative. Further well-designed large RCTs are required to substantiate its safety profile.

Effect of a subanesthetic dose of esketamine combined with propofol on postoperative fatigue syndrome in patients undergoing gastroenterological endoscopy under anaesthesia: A retrospective study

Objective

To assess the effect of subanesthetic dose of esketamine in combination with propofol on the incidence of postoperative fatigue syndrome (POFS) in patients who underwent gastroenterological endoscopy under anaesthesia.

Methods

Clinical data of 160 patients who underwent gastroenterological endoscopy under anaesthesia in Huzhou Maternity & Child Health Care Hospital from January to December 2022, ASA Grade- I and II, were retrospectively selected. According to the records, patients were grouped based on the administered anesthetic. Patients who received 0.2 mg/kg of esketamine and 2~2.5mg/kg of propofol comprised Group-E, and patients who were administered one μg/kg of fentanyl and 2 - 2.5mg/kg of propofol comprised Group-F. Mean arterial pressure (MAP), oxygen saturation (SpO2) and heart rate (HR) were recorded before the operation (T0), after anesthesia (T1), three minutes after the gastroscope was inserted (T2), five minutes after the colonoscope was inserted (T3) and at the end of the operation (T4). Operating time, recovery time, propofol dosage and incidence of adverse reactions in the two groups were recorded. The Christensen scores and the incidence of POFS of all patients on Day-I before operation and 1st, 3rd, and 5th days after the operation were recorded.

Results

Compared with T0, MAP, SpO2 and HR in both groups of patients decreased at T1, T2, T3 and T4 (P<0.05). MAP, SpO2 and HR of patients in Group-E were significantly higher compared to Group-F at T1, T2, T3 and T4 (P<0.05). Compared with Group-F, the recovery time, intraoperative bradycardia and respiratory depression in Group-E were significantly lower (P<0.05), and Christensen scores and the incidence of POFS decreased significantly on the 1st, 3rd, and 5th day after the operation (P<0.05).

Conclusion

Subanesthetic dose of esketamine combined with propofol can reduce POFS and postoperative adverse reactions in patients undergoing gastroenterological endoscopy.

Intravenous esketamine as an adjuvant for sedation/analgesia outside the operating room: a systematic review and meta-analysis

Background

This study was conducted to evaluate the safety and efficacy of intravenous esketamine as an adjuvant for sedation or analgesia outside the operating room in adults and children.

Method

PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, and Scopus were searched for potential randomized controlled studies randomized controlled trials comparing drug combinations of esketamine to any other single or combination drug regimens for sedation or analgesia outside the operating room.

Results

Twenty-five studies with a total of 3,455 participants were included in this review. The pooled results of adults showed that compared with drug regimens of the control group, intravenous esketamine combinations were significantly associated with decreased risk of oxygen desaturation (RR = 0.49, 95% CI = [0.34, 0.70]); hypotension (RR = 0.38, 95% CI = [0.31, 0.46]); bradycardia (RR = 0.23, 95% CI = [0.12, 0.43]); injection pain (RR = 0.37, 95% CI = [0.25, 0.53]); body movement (RR = 0.60, 95% CI = [0.41, 0.88]); and propofol consumption (SMD = -1.38, 95% CI = [-2.64, -0.11]), but an increased risk of psychiatric symptoms (RR = 3.10, 95% CI = [2.11, 4.54]) (RR = relative risk; CI = confidence intervals; SMD = standardized mean difference). Subgroup analysis showed that only the combination of esketamine and propofol significantly reduced the above incidence of respiratory and cardiovascular adverse events in adults. In addition, the pooled results of children showed that compared with drug regimens of the control group, esketamine and propofol co-administration significantly reduced the risk of hypotension (RR = 0.59, 95% CI = [0.37, 0.95]) but increased the risk of visual disturbance (RR = 6.62, 95% CI = [2.18, 20.13]) and dizziness (RR = 1.99, 95% CI = [1.17, 3,37]). Subgroup analysis indicated that esketamine>0.5 mg/kg significantly reduced the incidence of hypotension, but increased the risk of dizziness in children.

Conclusion

Intravenous use of esketamine, particularly in combination with propofol, may improve the safety and efficacy of sedation and analgesia outside the operating room, although the potential for psychiatric side effects warrants attention. Future research is recommended to investigate the role of esketamine with agents other than propofol.

Comparison of propofol-esketamine versus propofol-sufentanil for deep sedation and analgesia in children with autism: A randomized double-blind clinical trial

Propofol sedation, routinely used for endoscopic procedures, is safe and acceptable for children. Adjuvants, such as esketamine or sufentanil, are commonly added to improve the efficacy and safety of propofol sedation. This study aimed to compare the clinical efficacy and safety of propofol-esketamine (PE) versus propofol-sufentanil (PS) for deep sedation and analgesia in children with autism undergoing colonoscopy procedure. One hundred and twenty-four children with autism undergoing colonoscopy procedure were included in the study. Patients were randomly assigned to receive one of the two adjuvants: esketamine (0.3 mg/kg) or sufentanil (0.2 μg/kg), subsequently administered propofol 2.0 mg/kg to induce anesthesia. Additional doses of propofol (0.5-1.0 mg/kg) were administered as needed to ensure patient tolerance for the remaining duration of the procedure. Movement during the procedure, hemodynamic variables, the total dose of propofol, recovery time, and adverse events were recorded. The PE group exhibited a significantly lower incidence of severe movement during the procedure compared with the PS group (14.52% vs. 32.26%, p = 0.020). The PE group showed significantly lower incidence of respiratory depression, hypotension, and severe injection pain of propofol than the PS group during the procedure (all p < 0.05). The mean arterial pressure (MAP) decreased significantly after anesthesia induction in the PS group and remained lower than baseline (all p < 0.05). Compared with the combination of low-dose sufentanil (0.2 μg/mg) with propofol, the low-dose esketamine (0.3 mg/kg) combined with propofol provided more stable hemodynamics, higher quality of sedation, and fewer adverse events in children with autism undergoing colonoscopy procedure.

Comparison of the Safety and Efficacy of Remimazolam Besylate versus Dexmedetomidine for Patients Undergoing Fiberoptic Bronchoscopy: A Prospective, Randomized Controlled Trial

Objective

Remimazolam besylate is a novel ultra-short-acting benzodiazepine that is rapidly hydrolyzed to zolpidem propionic acid by tissue lipases. We designed this study to compare the safety and efficacy of remimazolam besylate alfentanil versus dexmedetomidine-alfentanil for fiberoptic bronchoscopy (FB).

Methods

One hundred and twenty patients undergoing FB into this prospective randomized controlled trial were divided into two groups. The anesthesia induction consisted of 6 mg/kg/h of remimazolam besylate in the RA group and 0.5 μg/kg of dexmedetomidine in the DA group. 1-2 mg/kg/h of remimazolam besylate or 0.2-0.7 µg/kg/h of dexmedetomidine were administered to maintain during FB. The lowest oxygen saturation, success rate of FB, hemodynamics, time metrics, bronchoscopy feasibility, drug dose requirements, patient and bronchoscopist satisfaction scores, occurrence of intraoperative awareness, number of patients willing to repeat FB with the same sedation regimen, and occurrence and severity of adverse events.

Results

The lowest oxygen saturation during the FB was significantly higher in the RA group (P = 0.001). Compared with the variables in the DA group, peripheral oxygen saturation, systolic blood pressure, and diastolic blood pressure were significantly lower at T2 and T3 in the RA group (P < 0.05). Heart rates were significantly higher from T2 to T4 in the DA group (P < 0.05). More patients experienced bradycardia in the DA group (P = 0.041). Compared with time metrics in the DA group, the induction time, fully-alert time, and recovery room-leaving time were all significantly shorter in the RA group (P < 0.05). The bronchoscopy feasibility scores in the RA group were significantly lower at T2, whereas they were lower at T3 in the DA group (P < 0.05).

Conclusion

Remimazolam besylate is superior to dexmedetomidine when combined with alfentanil during FB, promoting faster patients' recovery, better operative conditions and respiratory stability with similar rates of occurrence and severity of adverse events.

A study of hemodynamic effects, postoperative recovery, and safety of esketamine (right handed) during flexible bronchoscopy under general anesthesia

OBJECTIVE

Flexible bronchoscopy during general anesthesia has become an indispensable tool. Anesthetics are widely utilized in flexible bronchoscopy (FB). This study delved into the application value of a subanesthetic dose of esketamine (ES) (right handed) in flexible bronchoscopy during general anesthesia.

METHODS

A sample of 160 patients who underwent flexible bronchoscopy during general anesthesia were selected as study subjects and were equally divided into the control and ES groups, with clinical baseline data (age, sex, body mass index, American Society of Anesthesiologists grading) collected. Hemodynamic parameters (mean artery pressure, heart rate, pulse blood oxygen saturation) at different time points, the onset time of anesthesia, surgery time, analgesia maintenance time, anesthesia awakening time, and perioperative adverse reactions were recorded. Visual analogue scale (VAS), Mini-Mental State Examination (MMSE), and quality of recovery-40 (QoR-40) scales were utilized for assessing post-surgery satisfaction, cognitive function, and post-surgery early recovery quality.

RESULTS

The hemodynamics were stable at each time point, but patients in the ES group were more stable than those in the control group. Patients in the ES group exhibited faster onset and awakening time of anesthesia, longer duration of analgesia, and lower total incidence of adverse reactions versus the control group. The patients' QoR-40 total scores in the ES group were improved versus the control group at 1 day after surgery.

CONCLUSION

Compared with fentanyl, the use of ES (right handed) in flexible bronchoscopy during general anesthesia produces more stable hemodynamics, faster onset and recovery time of anesthesia, longer duration of analgesia, lower incidence of adverse reactions, and improved early postoperative recovery quality in patients.

Supplemental low-dose esketamine to propofol versus propofol alone on perioperative characteristics in children undergoing surgery: a prospective randomized controlled trial

BACKGROUND

Limited data exist regarding the use of the esketamine-propofol combination (esketofol) in pediatric surgery. This study aimed to investigate the effect of esketofol versus propofol alone on the perioperative characteristics of children undergoing minor surgery.

METHODS

Eighty-four children aged two to six years were randomly assigned to either the propofol group or the esketofol group. Intraoperative outcomes included bispectral index, dosage of anesthetics, and extubation time. Postoperative outcomes comprised oropharyngeal airway usage, time to orientation, time to eye-opening, length of stay in the post-anesthesia care unit, the need for rescue opioids, pain rating using the Face, Legs, Activity, Cry, Consolability (FLACC) Scale, Pediatric Anesthesia Emergence Delirium Score, nausea and vomiting, and psychotomimetic symptoms. The FLACC pain score was the primary outcome, and the remaining parameters were considered secondary outcomes.

RESULTS

The FLACC Score (2 [1, 3.3] vs. 4 [3, 5.3], P<0.001) and frequency of rescue opioids (14.3% vs. 33.3%, P=0.040) were significantly lower, while Bispectral Index (BIS) was higher (P<0.001) in the esketofol group compared with the propofol group. Moreover, the time to orientation and length of stay in the post-anesthesia care unit (PACU) were significantly longer in the esketofol group compared with the propofol group (P=0.029 and P=0.025, respectively). The other outcomes were similar between the two groups.

CONCLUSIONS

Esketofol reduces postoperative pain and the need for rescue opioids, but it extends recovery time in the PACU and increases BIS without affecting other outcomes.

The role and mechanism of esketamine in preventing and treating remifentanil-induced hyperalgesia based on the NMDA receptor-CaMKII pathway

Remifentanil-induced hyperalgesia (RIH) is a common clinical phenomenon that limits the use of opioids in pain management. Esketamine, a non-competitive N-methyl-d-aspartate (NMDA) receptor antagonist, has been shown to prevent and treat RIH. However, the underlying effect mechanism of esketamine on RIH remains unclear. This study aimed to investigate the role and mechanism of esketamine in preventing and treating RIH based on the NMDA receptor-CaMKIIα pathway. In this study, an experimental animal model was used to determine the therapeutic effect of esketamine on pain elimination. Moreover, the mRNA transcription and protein expression levels of CaMKII and GluN2B were investigated to offer evidence of the protective capability of esketamine in ameliorating RIH. The results demonstrated that esketamine attenuated RIH by inhibiting CaMKII phosphorylation and downstream signaling pathways mediated by the NMDA receptor. Furthermore, ketamine reversed the upregulation of spinal CaMKII induced by remifentanil. These findings suggest that the NMDA receptor-CaMKII pathway plays a critical role in the development of RIH, and ketamine's effect on this pathway may provide a new therapeutic approach for the prevention and treatment of RIH.