Efficacy and Safety of Esketamine for Supplemental Analgesia During Elective Cesarean Delivery: A Randomized Clinical Trial

Effects of perioperative application of esketamine on postpartum depression in cesarean section: A systematic review and meta-analysis

BACKGROUND

To evaluate the effect of perioperative esketamine administration on postpartum depression in pregnant women undergoing cesarean section.

METHODS

Data sources was PubMed, Embase, Web of Science, and Cochrane Library from inception to February 1, 2024. Randomized controlled trials in pregnant women undergoing cesarean section were selected and compared to the use of esketamine in the perioperative period. The primary outcome measure was the incidence of postpartum maternal depression. Preferred reporting items for systematic reviews and meta-analyses were used. Data pooled by random-effects models are presented as risk ratios (RR) (95% confidence intervals, 95% CI) or mean differences (95% CI). This review was registered in PROSPERO (ID: CRD42023431197).

RESULTS

We included 8 studies with a total of 1655 participants. The quality of the studies was rated high or unclear. Seven studies involving 1485 participants reported the incidence of postpartum depression. Compared with pregnant women undergoing cesarean section without the use of esketamine, those using esketamine in the perioperative period showed a 48% decreased risk of developing postpartum depression (RR: 0.52, 95% CI: 0.35-0.79) and a 1.43-point reduction in EPDS (Edinburgh Postnatal Depression Scale) (mean difference: -1.43, 95% CI: -2.32 to -0.54). For immediate intraoperative adverse reactions, the application of esketamine caused maternal nausea and vomiting (RR: 2.16, 95% CI: 1.22-3.81), dizziness (RR: 6.11, 95% CI: 1.49-24.98), and hallucinations (RR: 6.83, 95% CI: 1.57-29.68) compared to no esketamine use.

CONCLUSIONS

Perioperative use of esketamine in pregnant women undergoing cesarean section may reduce postpartum depression and increase intraoperative adverse reactions, but has no significant effect on postoperative adverse reactions.

Effect of esketamine combined with dexmedetomidine on delirium in sedation for mechanically ventilated ICU patients: protocol for a nested substudy within a randomized controlled trial

BACKGROUND

Use of sedatives and analgesics is associated with the occurrence of delirium in critically ill patients receiving mechanical ventilation. Dexmedetomidine reduces the occurrence of delirium but may cause hypotension, bradycardia, and insufficient sedation. This substudy aims to determine whether the combination of esketamine with dexmedetomidine can reduce the side effects and risk of delirium than dexmedetomidine alone in mechanically ventilated patients.

METHODS

This single-center, randomized, active-controlled, superiority trial will be conducted at The First Affiliated Hospital of Nanjing Medical University. A total of 134 mechanically ventilated patients will be recruited and randomized to receive either dexmedetomidine alone or esketamine combined with dexmedetomidine, until extubation or for a maximum of 14 days. The primary outcome is the occurrence of delirium, while the second outcomes include the number of delirium-free days; subtype, severity, and duration of delirium; time to first onset of delirium; total dose of vasopressors and antipsychotics; duration of mechanical ventilation; ICU and hospital length of stay (LOS); accidental extubation, re-intubation, re-admission; and mortality in the ICU at 14 and 28 days.

DISCUSSION

There is an urgent need for a new combination regimen of dexmedetomidine due to its evident side effects. The combination of esketamine and dexmedetomidine has been applied throughout the perioperative period. However, there is still a lack of evidence on the effects of this regimen on delirium in mechanically ventilated ICU patients. This substudy will evaluate the effects of the combination of esketamine and dexmedetomidine in reducing the risk of delirium for mechanically ventilated patients in ICU, thus providing evidence of this combination to improve the short-term prognosis. The study protocol has obtained approval from the Medical Ethics Committee (ID: 2022-SR-450).

TRIAL REGISTRATION

ClinicalTrials.gov: NCT05466708, registered on 20 July 2022.

Pharmacologic Analgesia for Cesarean Section: An Update in 2024

PURPOSE OF THE REVIEW

With the increasing prevalence of cesarean section globally, the importance of perioperative analgesia for cesarean section is becoming increasingly evident. This article provides an overview and update on the current status of cesarean section worldwide and associated analgesic regimens.

RECENT FINDINGS

Some recent studies unveiled potential association of neuraxial analgesia might be associated with children's autism, pharmacologic analgesia in obstetric will potentially gain some more attention. Various commonly used techniques and medications for analgesia in cesarean section are highlighted. While neuraxial administration of opioid remains the most classic method, the use of multimodal analgesia, particularly integration of nonsteroidal anti-inflammatory drugs, acetaminophen, peripheral nerve blocks has provided additional and better options for patients who are not suitable for intrathecal and neuraxial techniques and those experiencing severe pain postoperatively. Optimal pain management is crucial for achieving better clinical outcomes and optimal recovery, and with the continuous development of medications, more and better pharmacologic regimen will be available in the future.

Esketamine Combined with Dexmedetomidine to reduce Visceral Pain During elective Cesarean Section Under Combined Spinal-Epidural Anesthesia: A double-Blind Randomized Controlled Study

Purpose

We aimed to evaluate the effect of intravenous esketamine combined with dexmedetomidine as supplemental analgesia in reducing intraoperative visceral pain during elective cesarean section under combined spinal-epidural anesthesia (CSEA).

Patients and Methods

A total of 269 parturients scheduled for elective cesarean section under CSEA between May 2023 and August 2023 were assessed. The parturients were randomly allocated to receiving either intravenous infusion of 0.3-mg/kg esketamine combined with 0.5-μg/kg dexmedetomidine (group ED, n=76), 0.5-μg/kg dexmedetomidine (group D, n=76), or normal saline (group C, n=76) after umbilical cord clamping. The primary outcome was intraoperative visceral pain. Secondary outcomes included the visual analog scale (VAS) score for pain evaluation and other intraoperative complications.

Results

The incidence of visceral pain was lower in group ED [9 (12.7%)] than in group D [32 (43.8%)] and group C [36 (48.6%), P <0.0001]. The VAS score was also lower in group ED when exploring abdominal cavity [0 (0), P <0.0001] and suturing the muscle layer [0 (0), P =0.036]. The mean arterial pressure was higher in group D [83 (9) mmHg] and group ED [81 (11) mmHg] than in group C [75 (10) mmHg, P <0.0001] after solution infusion. The heart rate after infusion of the solution was lower in group D [80 (12) bpm] than in group C [86 (14) bpm] and group ED [85 (12) bpm, P = 0.016]. The incidence of transient neurologic or mental symptoms was higher in group ED compared to group C and group D (76.1% vs 18.9% vs 23.3%, P<0.0001).

Conclusion

During cesarean section, 0.3-mg/kg esketamine combined with 0.5-μg/kg dexmedetomidine can alleviate visceral traction pain and provide stable hemodynamics. Parturients receiving this regimen may experience transient neurologic or mental symptoms that can spontaneously resolve at the end of the surgery.

Comparison of Effects of Propofol Combined with Different Doses of Esketamine for ECT in the Treatment of Depression: A Randomized Controlled Trial Protocol

Objective

Major depressive disorder (MDD) is a common mood disorder. Electroconvulsive therapy (ECT) has a significant effect on treatment-resistant MDD. Esketamine may have potential advantages in improving the efficacy of ECT, and the strong affinity of this compound for NMDAR renders it a viable therapeutic option for the management of depression. This study aims to compare the effects of different doses of esketamine combined with propofol anesthesia versus propofol anesthesia alone in ECT, aiming to provide further insights for optimizing ECT and enhancing comprehensive treatment outcomes for depression.

Study Design and Methods

This study was a prospective, randomized, controlled, double-blind trial involving subjects and evaluators. One hundred eleven patients scheduled for ECT were randomly assigned to three groups. In Group P, propofol at 1mg/kg was administered intravenously. In Group P+E, propofol at a dosage of 0.5mg/kg and esketamine at a dosage of 0.5mg/kg was administered intravenously. Patients in Group P+SE received propofol at a dosage of 0.75mg/kg and esketamine at a dosage of 0.25mg/kg. The same anesthesia protocol was used for the same patient until the end of the last treatment. The primary outcome measures were the Hamilton depression scale (HAMD) and the Patient Health Questionnaire-9 (PHQ-9), the Columbia-Suicide Severity Rating Scale (C-SSRS), and the Digit symbol substitution test (DSST). Secondary outcomes included length of hospital stay, readmission rate, hemodynamic status, recovery, and adverse events.

Discussion

This study aimed to compare the effects of propofol combined with different doses of esketamine for ECT. The results may provide a better choice for ECT anesthesia.

The Relationship Between Perioperative Use of Esketamine and Postpartum Depression Risk: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Purpose

To determine whether perioperative esketamine use decreases the risk of postpartum depression (PPD).

Methods

Online search of PubMed, Web of Science, and Embase was conducted to identify relevant studies. Key words for search included, but were not limited to, postpartum depression, esketamine, and clinical trials. The mean and standard deviation of the Edinburgh Postnatal Depression Scale (EPDS) scores were extracted from the studies as primary parameters.

Results

The literature search identified 226 articles, of which 5 met the criteria and were enrolled in the study. In total, 886 patients in the studies were taken into analysis. The EPDS scores in the esketamine group were lower than those of the control group at the early stage of puerperium (WMD=-2.05, 95% CI: -3.77, -0.34, p=0.019), whereas there was no significant difference at the middle and later stages (WMD=-1.41, 95% CI: -2.86, 0.04, p=0.056). The sensitivity analyses indicated that the result for the early stage was stable, whereas it was unreliable for the middle and later stages. The results of the Egger's test indicated no publication bias.

Conclusion

Perioperative use of esketamine contributes to a lower risk of PPD at the early stage of puerperium but not at the middle and later stages. To further verify this conclusion, more high-quality studies are required.

Effect of intraoperative and/or postoperative esketamine administration on preventing postpartum depression: A systematic review and meta-analysis

This systematic review and meta-analysis aimed to evaluate the impact of intraoperative and/or postoperative esketamine application on the prevention of postpartum depression (PPD). PubMed, Embase, and Web of Science were thoroughly searched for eligible randomized controlled trials (RCTs) regarding the application of esketamine for postnatal depression prevention. Nine RCTs including 1277 participants were involved in the final analysis. It was found that intraoperative and/or postoperative administration of esketamine significantly reduced the PPD incidence and the Edinburgh Postnatal Depression Scores in the early postoperative period. Meanwhile, esketamine lowered the occurrence of postoperative nausea and vomiting with no influence on other psychiatric symptoms.

Efficacy and safety of esketamine for pediatric gastrointestinal endoscopy: a meta-analysis and trial sequential analysis

Objective

The role of esketamine in pediatric gastrointestinal endoscopy is still unclear. This study aims to evaluate the efficacy and safety of esketamine for pediatric gastrointestinal endoscopy.

Methods

Clinical trials of esketamine for pediatric gastrointestinal endoscopy were searched in eight common databases, up to October 2023. These clinical trials were included in the meta-analysis and trial sequential analysis (TSA). The risk ratio (RR) and weighted mean difference (WMD) were used as the effect sizes for dichotomous variables and continuity variables, respectively. When the heterogeneity test showed I2 < 50%, the fixed effects model was used for the meta-analysis and TSA; Otherwise, the random effects model was used for them.

Results

In terms of efficacy endpoints, the meta-analysis showed that compared with placebo or blank, esketamine significantly decreased recovery time by 2.34 min (WMD -2.34; 95% Confidence interval [CI] -3.65, -1.02; p = 0.0005) and propofol consumption by 0.70 mg/kg (WMD -0.70; 95% CI -0.98, -0.43; p < 0.00001), and increased mean heart rate by 4.77 beats/min (WMD 4.77; 95% CI 2.67, 6.87; p < 0.00001) and mean arterial pressure by 3.10 mmHg (WMD 3.10; 95% CI 1.52, 4.67; p = 0.0001), while induction time and mean blood oxygen remained comparable. TSA indicated conclusive evidence for these benefits. In terms of safety endpoints, the meta-analysis revealed that esketamine significantly reduced involuntary movements by 59% (RR 0.41; 95% CI 0.22, 0.76; p = 0.005) and choking by 51% (RR 0.49; 95% CI 0.26, 0.92; p = 0.03), while significantly increasing dizziness by 98% (RR 1.98; 95% CI 1.11, 3.56; p = 0.02) and there were no significant differences in total adverse events, respiratory depression, and vomiting. TSA demonstrated conclusive evidence for involuntary movements and dizziness. Low-dose analysis showed that esketamine at ≤0.3 mg/kg significantly reduced recovery time, propofol consumption and involuntary movements, and significantly increasing mean heart rate, with no increase in dizziness. The Begg's test (p = 0.327) and the Egger's test (p = 0.413) indicated no significant publication bias, yet the funnel plot suggested potential publication bias.

Conclusion

Esketamine is an effective adjuvant anesthesia for children undergoing gastrointestinal endoscopy. However, the general dose of esketamine may increase the risk of dizziness, which can be avoided by administering a low dose (≤0.3 mg/kg).

Effects of ketamine and esketamine on preventing postpartum depression after cesarean delivery: A meta-analysis

BACKGROUND

Ketamine and esketamine has been suggested to have potential efficacy in preventing postpartum depression (PPD) recent years. The aim of this meta-analysis was to evaluate the effectiveness of ketamine and esketamine on PPD after cesarean delivery.

METHODS

We systematically searched PubMed, Embase, and the Cochrane Library for studies investigating the efficacy of ketamine and esketamine in preventing PPD. The primary outcomes of this study were risk ratios (RRs) and EPDS scores (Edinburgh Postnatal Depression Scale) in relation to PPD after ketamine and esketamine. The second outcomes were the postoperative adverse events.

RESULTS

Thirteen randomized controlled trials (RCTs) and one retrospective study including 2916 patients were analyzed, including six on the use of ketamine and eight on the use of esketamine. The risk ratios and EPDS scores of PPD were significantly decreased in the ketamine/esketamine group compared to those in the control group in one week and four weeks postoperative periods. Subgroup analyses showed that high dosage, administrated in patient controlled intravenous analgesia (PCIA) method and only esketamine exhibited a significant reduction in the incidence and EPDS scores of PPD in one week and four week postoperative. However, the incidences of postoperative adverse events, such as dizziness, diplopia, hallucination, and headache were significantly higher in the ketamine/esketamine group than that in the control group.

CONCLUSION

Ketamine and esketamine appear to be effective in preventing PPD in the one week and four week postoperative periods after cesarean delivery with moderate certainty of evidence. But they can also lead to some short-term complications too. Future high-quality studies are needed to confirm the efficacy of ketamine and esketamine in different countries.

Efficacy of a single low dose of esketamine after childbirth for mothers with symptoms of prenatal depression: randomised clinical trial

OBJECTIVE

To determine whether a single low dose of esketamine administered after childbirth reduces postpartum depression in mothers with prenatal depression.

DESIGN

Randomised, double blind, placebo controlled trial with two parallel arms.

SETTING

Five tertiary care hospitals in China, 19 June 2020 to 3 August 2022.

PARTICIPANTS

364 mothers aged ≥18 years who had at least mild prenatal depression as indicated by Edinburgh postnatal depression scale scores of ≥10 (range 0-30, with higher scores indicating worse depression) and who were admitted to hospital for delivery.

INTERVENTIONS

Participants were randomly assigned 1:1 to receive either 0.2 mg/kg esketamine or placebo infused intravenously over 40 minutes after childbirth once the umbilical cord had been clamped.

MAIN OUTCOME MEASURES

The primary outcome was prevalence of a major depressive episode at 42 days post partum, diagnosed using the mini-international neuropsychiatric interview. Secondary outcomes included the Edinburgh postnatal depression scale score at seven and 42 days post partum and the 17 item Hamilton depression rating scale score at 42 days post partum (range 0-52, with higher scores indicating worse depression). Adverse events were monitored until 24 hours after childbirth.

RESULTS

A total of 364 mothers (mean age 31.8 (standard deviation 4.1) years) were enrolled and randomised. At 42 days post partum, a major depressive episode was observed in 6.7% (12/180) of participants in the esketamine group compared with 25.4% (46/181) in the placebo group (relative risk 0.26, 95% confidence interval (CI) 0.14 to 0.48; P<0.001). Edinburgh postnatal depression scale scores were lower in the esketamine group at seven days (median difference -3, 95% CI -4 to -2; P<0.001) and 42 days (-3, -4 to -2; P<0.001). Hamilton depression rating scale scores at 42 days post partum were also lower in the esketamine group (-4, -6 to -3; P<0.001). The overall incidence of neuropsychiatric adverse events was higher in the esketamine group (45.1% (82/182) v 22.0% (40/182); P<0.001); however, symptoms lasted less than a day and none required drug treatment.

CONCLUSIONS

For mothers with prenatal depression, a single low dose of esketamine after childbirth decreases major depressive episodes at 42 days post partum by about three quarters. Neuropsychiatric symptoms were more frequent but transient and did not require drug intervention.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04414943.

Perioperative Adjunctive Esketamine for Postpartum Depression Among Women Undergoing Elective Cesarean Delivery: A Randomized Clinical Trial

Importance

Postpartum depression (PPD) is one of the most common mental health conditions during the perinatal and postpartum periods, which can have adverse effects on both mother and infant.

Objective

To investigate the efficacy of perioperative adjunctive esketamine administration after cesarean deliveries in the prevention of PPD.

Design, Setting, and Participants

A single-center, double-blind, placebo-controlled, randomized clinical trial was conducted from January 1, 2022, to January 1, 2023, at Fujian Provincial Hospital among 298 women aged 18 to 40 years, with an American Society of Anesthesiologists grade I to III classification and singleton full-term pregnancies who were scheduled for elective cesarean deliveries. Primary analyses were performed on a modified intention-to-treat basis.

Interventions

Patients were randomly assigned to the esketamine (n = 148) and control (n = 150) groups. Those in the esketamine group received a single intravenous injection of 0.25 mg/kg of esketamine immediately after fetal delivery, followed by 50 mg of esketamine as an adjuvant in patient-controlled intravenous analgesia for 48 hours after surgery. Saline was given to the control group of patients.

Main Outcomes and Measures

The primary outcome was assessments of PPD symptoms by using the Edinburgh Postnatal Depression Scale (EPDS) at postpartum day 7. Positive screening for PPD was defined as a score of 10 or more points on the EPDS. In addition, the EPDS was analyzed as a continuous variable to evaluate depressive symptoms. Secondary outcomes included the Numeric Rating Scale (NRS) of postoperative pain, along with safety evaluations including adverse events and clinical assessments at postpartum days 14, 28, and 42.

Results

A total of 298 pregnant women were included, with 150 in the control group (median age, 31.0 years [IQR, 29.0-34.0 years]) and 148 in the esketamine group (median age, 31.0 years [IQR, 28.0-34.0 years]). The prevalence of depression symptoms was significantly lower among patients given esketamine compared with controls (23.0% [34 of 148] vs 35.3% [53 of 150]; odds ratio, 0.55; 95% CI, 0.33-0.91; P = .02) on postpartum day 7. In addition, the esketamine group also showed a significantly lower change in EPDS scores (difference of least-squares means [SE], -1.17 [0.44]; 95% CI, -2.04 to -0.31; effect size, 0.74; P = .008). However, there were no differences between the groups in the incidence of positive screening results for PPD or in changes from the baseline EPDS scores at postpartum days 14, 28, and 42. There were no differences in NRS scores at rest and on movement except on movement at 72 hours postoperatively, when scores were significantly lower in the esketamine group (median, 3.0 [IQR, 2.0-3.0] vs 3.0 [IQR, 3.0-3.5]; median difference, 0 [95% CI, 0-0]; P = .03).

Conclusions and Relevance

These results suggest that intravenous administration of esketamine during the perioperative period of elective cesarean delivery can improve depression symptoms during the early postpartum period. However, this antidepression effect may not be universally applicable to patients with low EPDS scores.

Trial Registration

Chinese Clinical Trial Registry Identifier: ChiCTR2100054199.

Association between esketamine interventions and postpartum depression and analgesia following cesarean delivery: a systematic review and meta-analysis

OBJECTIVE

This study aimed to compare the efficacy and safety of the use of esketamine to reduce the risk for postpartum depression and pain after cesarean delivery.

DATA SOURCES

Literature searches were conducted in PubMed, Embase, Cochrane Library, Web of Science, CNKI, and Wan fang from inception to August 2023.

STUDY ELIGIBILITY CRITERIA

The eligibility criteria were all randomized controlled trials of people who underwent a cesarean delivery and who were randomized to receive esketamine interventions irrespective of age or ethnicity. The outcomes that were assessed included the incidence of postpartum depression and the Edinburgh Postnatal Depression Scale score within 7 days and at 28 to 42 days after delivery, the pain score (visual analog scale or numerical rating scale, 0-10), the consumption of opioids, and intraoperative and postoperative adverse events.

METHODS

The Cochrane collaboration's tool was used for quality appraisal of the included studies. Statistical analysis of the data was performed using Review Manager 5.3 software, and the results were expressed as mean differences with 95% confidence intervals. Assessments were pooled using a random-effects or fixed-effects model. Study heterogeneity was assessed using the standard I2 statistic.

RESULTS

Among the 11 included randomized controlled trials that used the Edinburgh Postnatal Depression Scale for postpartum depression assessment, patients in esketamine group had a lower risk for postpartum depression within a week of surgery (risk ratio, 0.45; 95% confidence interval, 0.33-0.62). Intraoperative use of esketamine maintained a lower Edinburgh Postnatal Depression Scale score after surgery (mean difference, -1.64; 95% confidence interval, -2.14 to -1.14). Esketamine was associated with a beneficial effect in terms of the other outcomes, including a significant decline in pain score within 48 hours (mean difference, -0.71; 95% confidence interval, -0.89 to 0.52). Esketamine increased the risk for adverse neurologic and mental events during surgery without harming health, and there was no significant difference after delivery when compared with the control group.

CONCLUSION

Esketamine may reduce the risk for postpartum depression among patients who are undergoing cesarean delivery in the short term. In addition, as an adjunct to reduce analgesia, esketamine also effectively assists in pain management. Because of the lack of more high-quality evidence, we need more compelling evidence to confirm the value of esketamine in improving postpartum recovery.

Efficacy and safety of perioperative application of esketamine on postpartum depression: A meta-analysis of randomized controlled studies

Postpartum depression (PPD) seriously impairs the physical and mental health of mothers and their offspring, so how to prevent the occurrence of PPD has essential significance. Esketamine is a common general anesthetic that produces rapid and sustained antidepressant effects. However, the efficacy and safety of perioperative esketamine administration for PPD prevention remain uncertain. We conducted a meta-analysis to determine the effect of perioperative intravenous esketamine on PPD. Randomized controlled trials were included. The primary outcome was the prevalence of PPD and postpartum Edinburgh Postnatal Depression Scale (EPDS) scores. Secondary outcomes included postoperative pain scores and esketamine-related adverse effects. Seven studies included 669 patients treated with esketamine and 619 comparisons. Esketamine could effectively reduce EPDS scores and the incidence of PPD after cesarean section. Even at 42 days postpartum, the incidence of PPD was still significantly lower in the esketamine group. Esketamine did not increase the incidence of postoperative nausea and vomiting, dizziness, and drowsiness. In the esketamine low-dose subgroup, postoperative nausea and vomiting were significantly lower in the esketamine group. The two groups had no significant difference in postoperative pain scores. In conclusion, using esketamine during the perioperative period can reduce the incidence of PPD without increasing adverse effects.

Efficacy of Intravenous Administration of Esketamine in Preventing and Treating Rebound Pain After Thoracic Paravertebral Nerve Block: A Prospective Randomized, Double-Blind, Placebo-Controlled Trial

Purpose

Investigating the efficacy of intraoperative fractionated intravenous esketamine in the prevention of rebound pain after cessation of thoracic paravertebral nerve blockade.

Methods

One hundred and twenty patients who underwent elective thoracoscopic lobectomy were selected for the study and were randomly divided into two groups, the esketamine group was given 0.5 mg/kg and 0.3 mg/kg of esketamine at the induction of anaesthesia and 30 minutes before the end of the operation, respectively, and the control group was given an equal amount of saline. The incidence of rebound pain (RP) 7 days after surgery and postoperative recovery were compared between the two groups.

Results

The NRS pain scores at 24 and 48 hours postoperatively in the esketamine group were significantly lower than those in the control group (P < 0.05). The incidence of postoperative rebound pain was significantly lower in the esketamine group than in the control group (P < 0.05). The consumption of sufentanil was less in the esketamine group in the postoperative 48 hours (P < 0.05). Postoperative recovery was compared between the two groups and the difference was not statistically significant.

Conclusion

Intravenous esketamine reduces postoperative pain scores, decreases the incidence of rebound pain after cessation of thoracic paravertebral block, and reduces opioid consumption.

Impaired synaptic plasticity and decreased excitability of hippocampal glutamatergic neurons mediated by BDNF downregulation contribute to cognitive dysfunction in mice induced by repeated neonatal exposure to ketamine

AIM

Repeated exposure to ketamine during the neonatal period in mice leads to cognitive impairments in adulthood. These impairments are likely caused by synaptic plasticity and excitability damage. We investigated the precise role of brain-derived neurotrophic factor (BDNF) in the cognitive impairments induced by repeated ketamine exposure during the neonatal period.

METHODS

We evaluated the cognitive function of mice using the Morris water maze test and novel object recognition test. Western blotting and immunofluorescence were used to detect the protein levels of BDNF. Western blotting, Golgi-Cox staining, transmission electron microscopy, and long-term potentiation (LTP) recordings were used to assess synaptic plasticity in the hippocampus. The excitability of neurons was evaluated using c-Fos. In the intervention experiment, pAdeno-CaMKIIα-BDNF-mNeuronGreen was injected into the hippocampal CA1 region of mice to increase the level of BDNF. The excitability of neurons was enhanced using a chemogenetic approach.

RESULTS

Our findings suggest that cognitive impairments in mice repeatedly exposed to ketamine during the neonatal period are associated with downregulated BDNF protein level, synaptic plasticity damage, and decreased excitability of glutamatergic neurons in the hippocampal CA1 region. Furthermore, the specific upregulation of BDNF in glutamatergic neurons of the hippocampal CA1 region and the enhancement of excitability can improve impaired synaptic plasticity and cognitive function in mice.

CONCLUSION

BDNF downregulation mediates synaptic plasticity and excitability damage, leading to cognitive impairments in adulthood following repeated ketamine exposure during the neonatal period.

Apoptotic mechanism of development inhibition in zebrafish induced by esketamine

Esketamine, a widely used intravenous general anesthetic, is also employed for obstetric and pediatric anesthesia, and depression treatment. However, concerns regarding esketamine abuse have emerged. Moreover, the potential in vivo toxicity of esketamine on growth and development remains unclear. To address these concerns, we investigated the effects of esketamine exposure on developmental parameters, cell apoptosis, and gene expression in zebrafish. Esketamine exposure concentration-dependently decreased the heart rate and body length of zebrafish embryos/larvae while increasing the hatching rate and spontaneous movement frequency. Developmental retardation of zebrafish larvae, including shallow pigmentation, small eyes, and delayed yolk sac absorption, was also observed following esketamine treatment. Esketamine exposure altered the expression of apoptosis-related genes in zebrafish heads, primarily downregulating bax, caspase9, caspase3, caspase6, and caspase7. Intriguingly, BTSA1, a Bax agonist, reversed the anti-apoptotic and decelerated body growth effects of esketamine in zebrafish. Collectively, our findings suggest that esketamine may hinder embryonic development by inhibiting embryonic apoptosis via the Bax/Caspase9/Caspase3 pathway. To the best of our knowledge, this is the first study to report the lethal toxicity of esketamine in zebrafish. We have elucidated the developmental toxic effects of esketamine on zebrafish larvae and its potential apoptotic mechanisms. Further studies are warranted to evaluate the safety of esketamine in animals and humans.

Effect of Esketamine Added to Propofol Sedation on Desaturation and Hypotension in Bidirectional Endoscopy: A Randomized Clinical Trial

Importance

Propofol sedation is widely used for endoscopic procedures, but it poses risks of hemodynamic and respiratory depression. The addition of esketamine as an adjuvant may reduce propofol requirements and associated adverse events.

Objective

To evaluate the effects of low-dose esketamine added to propofol-based sedation on desaturation and hypotension during same-visit bidirectional endoscopy.

Design, Setting, and Participants

This multicenter, double-blind, placebo-controlled randomized clinical trial assessed patients from 3 teaching hospitals in China who were scheduled for same-visit bidirectional endoscopy between February 8 and November 30, 2022, and randomly assigned to receive esketamine or normal saline (placebo).

Interventions

After induction of sedation with 0.1 μg/kg of sufentanil and 0.5 mg/kg of propofol, patients in the esketamine group received 0.15 mg/kg of intravenous esketamine, whereas patients in the placebo group received an equivalent volume of saline. Sedation was achieved through propofol titration.

Main Outcomes and Measures

The primary outcome was the composite of desaturation and hypotension during the procedures. Secondary outcomes included desaturation, hypotension, propofol requirements, postprocedure pain and fatigue, nausea or vomiting, dizziness or headache, hallucination or nightmare, endoscopist satisfaction, and patient satisfaction.

Results

Among the 663 initially enrolled patients, 660 completed the study (median [IQR] age, 48 [36-57] years; 355 [53.8%] female), with 331 randomized to the esketamine group and 329 to the placebo group. The administration of esketamine compared with placebo significantly reduced the incidence of the composite outcome of desaturation and hypotension (8.2% vs 21.0%; difference, -12.8 percentage points; odds ratio [OR], 0.34; 95% CI, 0.21-0.54; P < .001). Additionally, esketamine led to significantly lower incidences of desaturation (OR, 0.36; 95% CI, 0.18-0.72; false discovery rate q = .01) and hypotension (OR, 0.33; 95% CI, 0.18-0.60; q < .001) and reduced propofol requirements (difference, -58.9 mg; 95% CI, -65.7 to -52.2 mg; q < .001), without significant effects on other secondary outcomes.

Conclusions and Relevance

In this randomized clinical trial of patients undergoing same-visit bidirectional endoscopy, the administration of low-dose esketamine resulted in an approximately 61% reduction in the incidence of desaturation and hypotension, accompanied by decreased propofol requirements. These findings support the use of esketamine as an adjuvant to propofol-based sedation in endoscopic procedures.

Trial Registration

Chinese Clinical Trial Registry Identifier: ChiCTR2200055938.