S-ketamine as an adjuvant in patient-controlled intravenous analgesia for preventing postpartum depression: a randomized controlled trial

Perioperative esketamine administration for prevention of postpartum depression after the cesarean section: A systematic review and meta-analysis

BACKGROUND

Postpartum Depression (PPD) exerts a substantial negative effect on maternal well-being post-delivery, particularly among Cesarean Section (C/S) recipients. In this study, we aimed to review the efficacy of perioperative esketamine, the S-enantiomer of ketamine, in preventing PPD incidence and depressive symptoms as measured with the Edinburgh Postnatal Depression Scale (EPDS) after C/S.

METHODS

A systematic search for relevant articles was conducted in Scopus, PubMed, Web of Sciences, and PsycINFO until April 6, 2024. Meta-analyses were conducted using random-effect models to compare the PPD incidence and EPDS scores via log odds ratio and Hedge's g, respectively, during the first week post-C/S and at 42 days post-C/S in the esketamine and control group.

RESULTS

Fourteen studies, including 12 randomized controlled trials and 2 retrospective cohorts, were reviewed. Our meta-analyses found lower PPD incidence during the first week (log odds ratio: -0.956 [95 % confidence interval: -1.420, -0.491]) and at day 42 post-C/S (log odds ratio: -0.989 [95 % confidence interval: -1.707, -0.272]) among patients administered esketamine compared to controls. Additionally, EPDS scores for the esketamine group were significantly lower than controls during the first week (Hedge's g: -0.682 [95 % confidence interval: -1.088, -0.276]) and at day 42 post-C/S (Hedge's g: -0.614 [95 % confidence interval: -1.098, -0.129]).

LIMITATIONS

Presence of various concomitant medications and heterogeneous study designs.

CONCLUSION

Our review highlights the potential impact of esketamine in PPD prevention, as well as in alleviating depressive symptoms post-C/S, regardless of PPD occurrence, therefore suggesting the benefits of adding esketamine to peri-C/S analgesic regimen.

Efficacy of ketamine versus esketamine in the treatment of perioperative depression: A review

Depression is a significant factor contributing to postoperative occurrences, and patients diagnosed with depression have a higher risk for postoperative complications. Studies on cardiovascular surgery extensively addresses this concern. Several studies report that people who undergo coronary artery bypass graft surgery have a 20% chance of developing postoperative depression. A retrospective analysis of medical records spanning 21 years, involving 817 patients, revealed that approximately 40% of individuals undergoing coronary artery bypass grafting (CABG) were at risk of perioperative depression. Patients endure prolonged suffering from illness because each attempt with standard antidepressants requires several weeks to be effective. In addition, multi-drug combination adjuvants or combination medication therapy may alleviate symptoms for some individuals, but they also increase the risk of side effects. Conventional antidepressants primarily modulate the monoamine system, whereas different therapies target the serotonin, norepinephrine, and dopamine systems. Esketamine is a fast-acting antidepressant with high efficacy. Esketamine is the S-enantiomer of ketamine, a derivative of phencyclidine developed in 1956. Esketamine exerts its effect by targeting the glutaminergic system the glutaminergic system. In this paper, we discuss the current depression treatment strategies with a focus on the pharmacology and mechanism of action of esketamine. In addition, studies reporting use of esketamine to treat perioperative depressive symptoms are reviwed, and the potential future applications of the drug are presented.

New treatments: Opportunities and challenges

Across the spectrum of perinatal mental illness, there exist a variety of effective treatments. However, the available treatments are not always matched to the presentation, resources, constraints, or values of each patient. Furthermore, provider, local, and systemic factors complicate access to current treatment options. New and emerging approaches offer the potential of more effective treatment for specific perinatal psychiatric disorders. From neuroactive steroid medications to accelerated psychotherapy interventions, recent innovations have demonstrated enhanced efficacy on a faster timeline. Optimally, these developments will also lower barriers to care but this is not necessarily true. We review novel and upcoming interventions across perinatal mental illness and place them in the context of existing treatments and common challenges.

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.

Efficacy and safety of peri-partum Esketamine for prevention of post-partum depression in women undergoing caesarian section: A meta-analysis and systematic review of randomized controlled trials

Postpartum depression (PPD) is a psychiatric condition affecting women post-childbirth. Medication combined with psychotherapy, is the current protocol for its treatment. A meta-analysis was conducted using RevMan 5.4 to explore the efficacy and safety of peri-partum administration of esketamine for preventing PPD. After searching several databases to retrieve the relevant RCTs, seven were included in this analysis, with dichotomous data presented as risk ratio and continuous data as mean difference. The study found a lower incidence of PPD in the esketamine group compared to the control group (RR= 0.37), with significant difference in EPDS scores between the two groups (MD= -1.23) in the first week postpartum. The esketamine group reported a lower prevalence of PPD 4-6 weeks postpartum (RR= 0.48), and no significant difference in EPDS scores after 4 weeks postpartum (MD = -0.10). The esketamine group had a significantly higher incidence of hallucination (RR= 13.85). Other adverse effects, such as dizziness (RR= 4.09), nausea (RR= 0.88), vomiting (RR=0.74), headache (RR=1.52), nightmares (RR=1.22), pruritus (RR=0.29), and drowsiness (RR=1.57) did not show significant differences between the two groups. The study found that esketamine, with manageable side effects, reduces the prevalence of post-partum depression (PPD) after one week as well as after four to six weeks. However, the findings are limited by the limited number of available RCTs, and future research should determine the ideal dosage, the most effective method of administration and the long-term safety profile of esketamine so that it may be considered as an adjunct therapy or a potential sole treatment option.

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.

Understanding and treating postpartum depression: a narrative review

Postpartum depression (PPD) is an increasingly prevalent but still poorly characterized disorder. Causal and modulating factors include hormones fluctuations, such as estrogen, progesterone, and allopregnolone, pathways imbalances, such as oxytocin and kynurenine, chronobiological factors, and brain imaging alterations. Treatment may differ from the traditional major depression management, while selective serotonin reuptake inhibitors such as sertraline are commonly used and suggested by guidelines, neurosteroids such as brexanolone and the more convenient zuranolone have been recently approved. Newer neurosteroids such as ganaxolone, valaxanolone, and lysaxanolone are currently under development, but also esketamine and psychedelics are promising potential treatments. Other somatic treatments including brain stimulation techniques and light therapy also showed benefit. PPD is therefore increasingly understood as, at least partially, independent from major depressive disorder. Specific and individualized treatments including pharmacological and non-pharmacological therapies are progressively being introduced in the routine clinical practice.

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.

Efficacy of perioperatively application of ketamine on postoperative depressive symptoms in adult patients: A systematic review and meta-analysis with trial sequential analysis

BACKGROUND

Whether ketamine used in the perioperative period reduces the risk of postoperative depressive symptoms remains uncertain. We conducted this systematic review and meta-analysis to evaluate the clinical efficacy of ketamine in adult surgical patients.

METHODS

Two investigators independently systematically searched the Cochrane Central Register of Controlled Trials (CENTRAL), Medline, Web of Science, and PsycINFO databases using a combination of relevant Medical Subject Headings terms and free-text keywords from database inception through May 24, 2023.

RESULTS

29 studies encompassing 5327 patients were included. The pooled analysis demonstrated that the ketamine group had no significantly reduced incidence of postoperative depressive mood compared with the control group, with trial sequential analysis (TSA) inconclusive. However, postoperative depression scale scores were significantly decreased in the ketamine group.

LIMITATIONS

Most randomized controlled trials of surgical patients have included depression scale scores as the primary outcome. The incidence of postoperative depressive has been assessed as a secondary outcome or has not been assessed. In addition, non-uniform assessment scales have introduced greater heterogeneity. More rigorous methods and higher-quality evidence for further research are needed to better understand the effects of ketamine on perioperative depression in surgical anesthesia.

CONCLUSIONS

Current evidence suggests that ketamine cannot significantly decrease the incidence of postoperative depressive mood in adult surgical patients. However, ketamine can reduce postoperative depression scores. PROSPERO registration: CRD42023431566.

Efficacy and safety of esketamine for perioperative depression in patients undergoing elective surgery: A meta-analysis of randomized controlled trials

BACKGROUND

Depression is a prevalent mood disorder during the perioperative period, with both preoperative concurrent depression and new-onset postoperative depression impacting postoperative recovery. Recent studies have indicated that the dissociative anesthetic esketamine may alleviate perioperative depressive symptoms.

OBJECTIVE

This meta-analysis aimed to assess the efficacy and safety of esketamine in treating perioperative depression.

METHODS

We selected randomized controlled trials comparing esketamine to placebo in terms of postoperative depressive symptoms. The primary outcome was postoperative depression scores, with secondary outcomes including the prevalence of postoperative depression, pain scores using the Visual Analogue Scale or Numeric Rating Scale, and incidences of adverse reactions such as nausea/vomiting, dizziness, dreams/nightmares, hallucinations.

RESULTS

We enrolled a total of 17 studies involving 2462 patients. The esketamine group demonstrated a significant reduction in postoperative depression scores within one week after surgery (SMD -0.47, 95% CI (-0.66, -0.27), P < 0.001) and over the long term (SMD -0.44, 95% CI (-0.79, -0.09), P = 0.01). Furthermore, esketamine significantly decreased the prevalence of postoperative depression both within one week (RR 0.46, 95% CI (0.33, 0.63), P < 0.001) and over the long term (RR 0.50, 95% CI (0.36, 0.70), P < 0.001). Additionally, esketamine effectively relieved pain on the first postoperative day compared to control. However, it also increased the risks of dizziness and hallucinations for a short time.

CONCLUSION

This meta-analysis suggests that the intraoperative or postoperative application of esketamine could be a potentially effective treatment for perioperative depression, although the increased risk of adverse reactions should be considered.

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.

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.

The efficacy of nasal administration of esketamine in patients having moderate-to-severe pain after preoperative CT-guided needle localization: a randomized, double-blind, placebo-controlled trial

Background

Whether nasal administration of esketamine can provide effective analgesia is unclear in patients with acute pain after preoperative CT-guided needle localization.

Methods

In this double-blind, randomized, placebo-controlled trial, patients were assigned to receive either nasal administration of esketamine (0.3 mg/kg or 0.5 mg/kg) or saline (identical in appearance to esketamine) when they had visual analog scale (VAS) pain scores >3/10 during deep breathing after preoperative CT-guided needle localization. The primary outcome was the percentage of patients with satisfactory pain relief, which was defined as VAS pain scores ≤3/10 measured 15 min after intranasal of esketamine or saline. Secondary outcomes included VAS measured following esketamine or saline, the incidence and cumulative dose of rescue hydromorphone use, and related adverse events.

Results

A total of 90 patients were included in the final analysis. Following intranasal treatment, the percentage of patients with satisfactory pain relief was 16.7% (5/30) in the saline group, 56.7% (17/30) in the 0.3 mg/kg esketamine group, and 53.3% (16/30) in the 0.5 mg/kg esketamine group (p = 0.002). The median VAS during deep breathing was less after the intranasal administration of esketamine {median (IQR), 3 (3, 5) in 0.3 mg/kg or 0.5 mg/kg esketamine compared to the saline group [5 (4, 6)], p = 0.009}. The incidence of rescue hydromorphone use was detected less in the esketamine group compared to the saline group (43.3% in the 0.3 mg/kg esketamine group, 36.7% in the 0.5 mg/kg esketamine group, and 73.3% in the saline group, p = 0.010). The adverse events were similar among the three groups (p > 0.05).

Conclusion

Intranasal administration of esketamine is easier and more effective in alleviating acute pain in patients after preoperative CT-guided needle localization without significant adverse effects.

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.

Ketamine causes poor maternal care in rats with postpartum depression and leads to few behavioral and neurochemical alterations on male offspring

Ketamine is an anesthetic drug that also has antidepressant properties, with quick action. Despite the great number of studies showing its effectiveness as a treatment for major depression, there is little information about its effects on postpartum depression, as pharmacological treatments bring risks to the health of both mother and child. Thus, this study aimed to evaluate the effects of prolonged treatment with subanesthetic doses of ketamine in a rat model of postpartum depression. Female dams were induced to postpartum depression by the maternal separation model from lactating day (LD) 2-12. They were divided into four groups: one control and three experimental groups, which were treated with different doses of ketamine (5, 10 or 20 mg/kg) from LD 2-21 i.p. Maternal studies were conducted from LD5 to LD21 and the offspring studies from postnatal day 2 through 90. Ketamine causes poor maternal care, with few neurochemical alterations. However, the highest dose used in this study had an antidepressant effect. Regarding the male offspring, indirect exposure to ketamine through breast milk caused few behavioral changes during infancy, but they were not permanent, as they faded in adulthood. Nevertheless, this exposure was able to cause alterations in their monoaminergic neurotransmission systems that were found in both infancy and adulthood periods.

Esketamine combined with sufentanil versus sufentanil in patient-controlled intravenous analgesia: a meta-analysis

Objective: Patient-controlled intravenous analgesia (PCIA) can alleviate pain to some extent, and several randomized controlled trials (RCTs) have examined the efficacy of esketamine-assisted sufentanil in postoperative PCIA. In this research, we conducted a meta-analysis of relevant RCTs to compare the effect and safety of esketamine-sufentanil versus sufentanil alone for postoperative PCIA. Methods: We systematically searched the Cochrane Library, PubMed, Embase, Web of Science, CNKI, and other libraries up to December 2023 to screen out RCTs examining the use of esketamine combined with sufentanil for PCIA. We analysed analgesia scores, sedation scores, adverse drug reactions and postpartum depression scores as outcome indicators. Results: This meta-analysis included 32 RCTs. The results of the meta-analysis were as follows. 1) Visual Analog Scale: The VAS scores at 6, 12, 24, and 48 h were lower in the esketamine-sufentanil group than in the sufentanil alone group, and significant differences were found at all time points (p < 0.05). 2) Ramsay Sedation Scale: The sedation score of the esketamine-sufentanil group at 48 h after surgery was higher than that of the sufentanil group alone [mean difference (MD) = -0.09 points, confidence interval (CI): (-0.26, -0.07), p = 0.27], but this difference was not significant (p > 0.05). 3) Safety: Compared with sufentanil alone, the incidence rates of postoperative nausea-vomiting, dizziness-headache, skin pruritus and respiratory depression were significantly lower in the esketamine-sufentanil group. 4) Postartum depression: The reduction in postpartum depression scores were significantly greater in the esketamine-sufentanil group than in the sufentanil alone group at 3 days [MD = -1.35 points, CI: (-1.89, -0.81), p < 0.00001] and 7 days [MD = -1.29 points, CI: (-2.42, -0.16), p = 0.03]. Conclusion: The meta-analysis showed that the use of esketamine combined with sufentanil for postoperative PCIA could improve postoperative analgesia, alleviate postpartum depression and reduce the rate of postoperative adverse reactions, but there was no significant difference in sedation.

Efficacy of esketamine for the treatment of postpartum depression and pain control following cesarean section: a randomized, double-blind, controlled clinical trial

BACKGROUND

Postpartum depression (PPD) following a cesarean delivery is a frequently seen complication. Despite the prophylactic effects of ketamine, the impact of esketamine on PPD in women undergoing cesarean section remains uncertain. This study aimed to assess the effectiveness of esketamine as an adjunct to patient-controlled intravenous analgesia (PCIA) in preventing PPD in women undergoing caesarean section.

METHODS

A total of 275 parturients undergoing caesarean section and subsequent patient-controlled intravenous analgesia (PCIA) were randomly assigned to receive either the control treatment (sufentanil 2 µg/kg + tropisetron 10 mg) or the experimental treatment with additional esketamine (1.5 mg/kg). The primary outcome measured was the incidence of postpartum depression (PPD), classified by Edinburgh Postnatal Depression Scale (EPDS) scores equal to or greater than 13 indicating PPD. Secondary outcomes included cumulative sufentanil consumption during specific time periods (0-24 h, 24-48 h, and 0-48 h) after the surgical procedure and numerical rating scale (NRS) scores at rest and during movements.

RESULTS

The final analysis included a total of 246 postpartum women who had undergone caesarean delivery. On postoperative day 42, the incidence of depression among the control group was 17.6%, which was significantly higher compared to the esketamine group with a rate of 8.2% (P = 0.02). The EPDS scores also showed a significant difference between the two groups, with a mean score of 9.02 ± 2.21 in the control group and 6.87 ± 2.14 in the esketamine group (p < 0.0001). In terms of pain management, the esketamine group showed lower sufentanil consumption in the 0-24 h (42.5 ± 4.58 µg vs. 50.15 ± 5.47 µg, P = 0.04) and 0-48 h (87.40 ± 9.51 µg vs. 95.10 ± 9.36 µg, P = 0.04) postoperative periods compared to the control group. Differences in movement were also observed between the two groups at 24 and 48 h after the cesarean Sect. (3.39 ± 1.57 vs. 4.50 ± 0.80, P = 0.02; 2.43 ± 0.87 vs. 3.56 ± 0.76, P = 0.02). It is worth noting that the frequency of side effects observed in both groups was comparable.

CONCLUSIONS

Esketamine at a dose of 1.5 mg/kg, when used as a supplement in PCIA, has been shown to significantly reduce the occurrence of PPD within 42 days. Additionally, it has been found to decrease cumulative consumption of sufentanil over a 48-hour period following cesarean operation, all without increasing the rate of adverse effects.

TRIAL REGISTRATION

Registered in the Chinese Clinical Trial Registry (ChiCTR2200067054) on December 26, 2022.

Effect of three modalities on emergence agitation among post-traumatic stress disorder patients undergoing laparoscopy: a randomized controlled study

BACKGROUND AND AIM

Emergence agitation (EA) after general anesthesia is common in patients with post-traumatic stress disorder (PTSD). Due to the recent worldwide events such as the Covid-19 pandemic and wars, PTSD is not rare. Accordingly, a reliable, cost-effective anesthetic protocol to lower the incidence of EA is crucial. Therefore, we aimed to compare three different interventions for avoiding EA in PTSD patients undergoing gynecological laparoscopic surgery. Participants were divided into four groups: 1: performing pre-operative relaxation techniques (deep breathing exercise and progressive muscle relaxation [PMR]); 2: administrating intra-operative Ketamine; 3: applying both previously mentioned strategies and 4 as controls.

METHODS

This study was carried out on 144 adult women scheduled for gynecological laparoscopy, randomly allocated into four groups: three intervention groups and a control group (36 each). Women aged 18-45 years old, with a diagnosis of PTSD were included in the study. Patients with a positive history of major neurological, cardiovascular, metabolic, respiratory, or renal disease were excluded. Any patient who reported the use of psychiatric drugs were also excluded from the study. Data was analyzed using IBM SPSS Statistics software version 26. Kolmogorov- Smirnov was used to verify the normality of the distribution of variables. Odds ratio was calculated to clarify the strength and direction of the association between intervention groups and control. Data was deemed significant at a p-value ≤0.05.

RESULTS

Heart rate (HR) and Mean Arterial Blood Pressure (MABP) intra-operative and post-operative till 24 hours were significantly lower in groups 1, 2, and 3 compared to group 4 (p<0.001). There was a significant statistical difference in the intraoperative HR percentage decrease. MABP percentage decrease post-operative was higher in all the intervention groups with no statistically significant difference, except for group 1 compared to group 4, which was statistically significant (12.28 ± 11.77 and 6.10 ± 7.24, p=0.025). Visual Analogue Scale measurements were significantly less in the intervention groups 1, 2, and 3 compared to group 4. On Riker sedation-agitation scores, group 1 was 85 times more likely to be non-agitated (85 (15.938 - 453.307), p<0.001), group 2 was 175 times more likely to be non-agitated (175 (19.932-1536.448), p<0.001) and group 3 was protected against agitation.

CONCLUSION

Pre-operative relaxation techniques (breathing exercises and PMR) significantly lowered HR, MABP, VAS score, and EA than controls. These effects were not significantly different from intra-operative ketamine injection or the combination of both (relaxation techniques and ketamine). We recommend routine pre-operative screening for PTSD and the application of relaxation techniques (breathing exercises and PMR) in the pre-operative preparation protocol of PTSD-positive cases as well as routine practical application of preoperative relaxation techniques. Further studies on using pre-operative relaxation techniques in general could be cost-effective.

Esketamine pretreatment during cesarean section reduced the incidence of postpartum depression: a randomized controlled trail

BACKGROUND

Postpartum depression (PPD) is a common mental disease in postpartum women, which has received more and more attention in society. Ketamine has been confirmed for its rapid antidepressant effect in women with PPD. We speculate that esketamine, an enantiomer of ketamine, pretreatment during cesarean can also reduce the incidence of PPD.

METHODS

All the parturients enrolled in the study were randomly assigned to two groups: the esktamine group (0.2 mg/kg esketamine) and the control group (a same volume of saline). All the drugs were pumped for 40 min started from the beginning of the surgery. The Amsterdam Anxiety and Information Scale (APAIS) scores before the surgery, the Edinburgh postnatal depression scale (EPDS) scores at 4 d and 42 d after surgery, the Pain Numerical Rating Scale (NRS) scores at 6 h, 12 h, 24 h and 48 h post-operation were evaluated, as well as the adverse reactions were recorded.

RESULTS

A total of 319 parturients were analyzed in the study. The incidence of PPD (EPDS score > 9) in the esketamine group was lower than the control group at 4 days after surgery (13.8% vs 23.1%, P = 0.0430) but not 42 days after surgery (P = 0.0987). Esketamine 0.2 mg/kg could reduce the NRS score at 6 h,12 h and 24 h after surgery, as well as the use of vasoactive drugs during surgery (P < 0.05). The incidences of maternal dizziness (17.0%), blurred vision (5%), illusion (3.8%) and drowsiness (3.8%) in the esketamine group were higher than those of control group (P < 0.05).

CONCLUSIONS

Intraoperative injection of esketamine (0.2 mg/kg) prevented the occurrence of depression (EPDS score > 9) at 4 days after delivery but not 42 days. Esketamine reduced the NRS scores at 6 h, 12 h and 24 h after surgery, but the occurrence of maternal side effects such as dizziness, blurred vision, drowsiness and hallucination were increased.

TRIAL REGISTRATION

Registered in the Chinese Clinical Trial Registry (ChiCTR2100053422) on 20/11/2021.

Analgesic Effect of Esketamine Combined with Tramadol for Patient-Controlled Intravenous Analgesia After Cesarean Section: A Randomized Controlled Trial

Purpose

High rate of cesarean section (CS) bring challenges to analgesic management after CS. Previous studies state that adjuvant treatment with a low dose of esketamine intraoperatively could reduce postoperative pain and opioid consumption, and even prevent postpartum depression. However, few researches involve in patient-controlled intravenous analgesia (PCIA) with esketamine after CS. In this trial, we explored a new combination of esketamine with tramadol for PCIA after CS with the aim to provide a better analgesic regimen for use in the clinic.

Patients and Methods

170 puerperae undergoing CS were recruited for this trial and randomly assigned into 2 groups (1:1): The control group received a formula of PCIA with butorphanol 0.1mg/kg and tramadol 400mg postoperatively, while the intervention group received a formula of PCIA with esketamine 1mg/kg and tramadol 400mg. The primary outcome was the mean numerical rating scale (NRS) scores at rest, sitting, and uterine contraction at 6 hours postoperatively. The second outcomes included the mean NRS scores at rest, sitting, and uterine contraction at 12, 24, and 48 hours postoperatively. The incidence of adverse events, postoperative sedation, postoperative sleep quality, maternal satisfaction regarding postoperative analgesia and the Edinburgh postnatal depression scale (EPDS) score were also be evaluated.

Results

The mean (SD) of the mean NRS scores at rest, sitting, and during uterine contraction at 6 hours postoperatively were 4.8 (0.7) points in the intervention group and 5.3 (0.5) points in the control group. The estimated mean difference between the two groups at 6 hours postoperatively was -0.5 points (95% confidence interval [CI], -0.7 to -0.3; P < 0.001). Compared with the control group, the patients in the intervention group had a significantly lower mean pain intensity at 12 and 24 hours postoperatively (-0.5 points [95% CI, -0.6 to -0.3]; P < 0.001 and -0.2 points [95% CI, -0.4 to 0]; P = 0.019 respectively). Otherwise, differences at 48 hours after surgery between the two groups were nonsignificant (0 points [95% CI, -0.2 to 0.2]; P = 0.802). The incidence of adverse events in the intervention group (11.8%) was significantly lower than in the control group (24.7%) (ratio difference -12.9, [95% CI, -24.3 to -1.5]; P = 0.029). No difference was found in postoperative sleep quality (P = 0.765), analgesic satisfaction (P= 0.818) and EPDS scores (P = 0.154) between the two groups.

Conclusion

In this trial, among patients undergoing CS, esketamine combined with tramadol by PCIA improved pain intensity 6 hours postoperatively compared with butorphanol combined with tramadol.

Effects of perioperative use of esketamine on postpartum depression risk in patients undergoing cesarean section: A randomized controlled trial

BACKGROUND

Postpartum depression (PPD) is a prevalent public health issue. Although ketamine has prophylactic effects on PPD in women undergoing cesarean section, the effects of esketamine on PPD remain unclear. This trial aimed to evaluate the efficacy of perioperative esketamine infusion on PPD risk by assessing Edinburgh Postnatal Depression Scale (EPDS) scores and blood biomarkers.

METHODS

A total of 150 participants undergoing elective cesarean section were randomly allocated to receive either esketamine or normal saline. Since 27 participants were excluded due to consent withdrawal or loss to follow-up, 123 patients were included. The primary outcome was the prevalence of PPD risk. Secondary outcomes included the prevalence of postpartum anxiety (PPA) risk, levels of biomarkers, postoperative pain intensity, and cumulative sufentanil consumption.

RESULTS

The prevalence of PPD and PPA risk at 3 days, 42 days, 3 months, and 6 months postpartum did not differ between the two groups. Furthermore, EPDS scores, pain intensity at rest, and during coughing on postoperative days (POD) 1 and 2 did not differ between the two groups. Sufentanil consumption during 0-12 h, 12-24 h, 0-24 h, and 0-48 h postoperatively were significantly lower in the esketamine group compared to the control group. Blood biomarkers did not differ between the two groups on POD 3.

LIMITATIONS

The sample size was small. PPD risk was simply screened, not diagnosed.

CONCLUSIONS

Perioperative administration of esketamine did not decrease the incidence of PPD risk in women after elective cesarean section. However, esketamine reduced opioid consumption.

Predicting efficacy of sub-anesthetic ketamine/esketamine i.v. dose during course of cesarean section for PPD prevention, utilizing traditional logistic regression and machine learning models

OBJECTIVE

Increasing researches supported that intravenous ketamine/esketamine during the perioperative period of cesarean section could prevent postpartum depression(PPD). With the effective rate ranging from 87.2 % to 95.5 % in PPD, ketamine/esketamine's responsiveness was individualized. To optimize ketamine dose/form based on puerpera prenatal characteristics, reducing adverse events and improving the total efficacy rate, prediction models were developed to predict ketamine/esketamine's efficacy.

METHOD

Based on two randomized controlled trials, 12 prenatal features of 507 women administered the ketamine/esketamine intervention were collected. Traditional logistics regression, SVM, random forest, KNN and XGBoost prediction models were established with prenatal features and dosage regimen as predictors.

RESULTS

According to the logistic regression model (ain = 0.10, aout = 0.15, area under the receiver operating characteristic curve, AUC = 0.728), prenatal Edinburgh Postnatal Depression Scale (EPDS) score ≥ 10, thoughts of self-injury and bad mood during pregnancy were associated with poorer ketamine efficacy in PPD prevention, whilst a high dose of esketamine (0.25 mg/kg loading dose+2 mg/kg PCIA) was the most effective dosage regimen and esketamine was more recommended rather than ketamine in PPD. The AUCvalidation set of KNN and XGBoost model were 0.815 and 0.651, respectively.

CONCLUSION

Logistic regression and machine learning algorithm, especially the KNN model, could predict the effectiveness of ketamine/esketamine iv. during the course of cesarean section for PPD prevention. An individualized preventative strategy could be developed after entering puerpera clinical features into the model, possessing great clinical practice value in reducing PPD incidence.

Effect of esketamine on inflammatory factors in opioid-free anesthesia based on quadratus lumborum block: A randomized trial

BACKGROUND

As strong analgesics, opioids provide the analgesic component of general anesthesia, but they have bidirectional effects on the immune system, promoting the production of pro-inflammatory factors. The idea of opioid-free anesthesia is to replace the analgesic effect of opioids in the treatment of acute pain with comparably effective drugs that do not affect the immune system and thereby decrease the production of inflammatory factors. Therefore, this study aims to observe the effect of opioid-free esketamine anesthesia based on quadratus lumborum block on inflammatory factors in patients undergoing lower abdominal or pelvic surgery.

METHODS

A total of 122 patients who underwent lower abdominal or pelvic surgery in our hospital from March 2021 to June 2022 were selected and divided into the esketamine (E) group (n = 62) and control (C) group (n = 60) according to the random number table method. According to the surgical field, the 2 groups underwent unilateral/bilateral quadratus lumborum block in the supine position under ultrasound guidance. In addition, both groups received a target controlled infusion of propofol 3 to 3.5 μg/mL and intravenous rocuronium 0.8 mg/kg. Group E was given opioid-free anesthesia, group C was given opioid-based anesthesia. A 3 to 5 laryngeal mask was inserted according to body weight, and rocuronium 0.5 mg/kg was added intermittently. The levels of interleukin-6 (IL-6), interleukin-8 (IL-8), C-reactive protein (CRP), procalcitonin, tumor necrosis factor-α (TNF-α), numeric rating scales, dosage of propofol, dexmedetomidine and rocuronium, as well as the numeric rating scales score and analgesic complications were monitored in the 2 groups.

RESULTS

There was no significant differences in general outcomes between the 2 groups (P > .05). The blood pressure in group E was higher than in group C at T1 (P < .05). The levels of IL-6, TNF-α, CRP and IL-8 in group E were significantly lower than in group C at T1, T2, T3, and T4 (P < .05). The levels of IL-6, TNF-α, procalcitonin, CRP and IL-8 in the 2 groups at T1, T2, T3, and T4 were significantly higher than at T0 (P < .05).

CONCLUSION

Opioid-free esketamine anesthesia based on quadratus lumborum block achieved perfect postoperative analgesia with little effect on inflammatory factors in patients undergoing lower abdominal or pelvic surgery.

Recent advances in the study of anesthesia-and analgesia-related mechanisms of S-ketamine

Ketamine is a racemic mixture of equal amounts of R-ketamine and S-ketamine and is well known to anesthesiologists for its unique dissociative anesthetic properties. The pharmacological properties of ketamine, namely, its sympathetic excitation, mild respiratory depression, and potent analgesia, are still highly valued in its use as an anesthetic for some patients. In particular, since its advent, S-ketamine has been widely used as an anesthetic in many countries due to its increased affinity for NMDA receptors and its enhanced anesthetic and analgesic effects. However, the anesthetic and analgesic mechanisms of S-ketamine are not fully understood. In addition to antagonizing NMDA receptors, a variety of other receptors or channels may be involved, but there are no relevant mechanistic summaries in the literature. Therefore, the purpose of this paper is to review the mechanisms of action of S-ketamine on relevant receptors and systems in the body that result in its pharmacological properties, such as anesthesia and analgesia, with the aim of providing a reference for its clinical applications and research.

Pharmacokinetics of Ketamine Transfer Into Human Milk

PURPOSE/BACKGROUND

Ketamine is an N -methyl- d -aspartate-antagonistic dissociative anesthetic infused intermittently for off-label management of treatment-resistant depression, acute suicidality, and postpartum depression. Despite the prevalence of postpartum depression nearing upward of 15% of deliveries, almost no research has been done to evaluate its safety during lactation.

METHODS

In this study, human milk samples were released from the InfantRisk Center's Human Milk Biorepository of 4 participants treated with intermittent ketamine infusions (49-378 mg) to determine the levels of the drug and its active norketamine metabolite using liquid chromatography-mass spectrometry.

RESULTS

The absolute infant dose of ketamine from human milk was 0.003 to 0.017 mg/kg per day, and norketamine was 0.005 to 0.018 mg/kg per day. The relative infant dose (RID) for ketamine ranged from 0.34% to 0.57%. The RID for norketamine ranged from 0.29% to 0.95%. There were no reported infant adverse effects.

CONCLUSION

The findings of this study suggest that the transfer of ketamine, as well as its active metabolite, norketamine, into human milk is minimal, as estimated by RIDs less than 1% in all participants. These relative doses are well below standardly accepted safety thresholds.

Effect of postoperative application of esketamine on postoperative depression and postoperative analgesia in patients undergoing pancreatoduodenectomy: a randomized controlled trial protocol

BACKGROUND

Pancreatoduodenectomy (PD) is traumatic, difficult to perform, and has a high incidence of postoperative complications and perioperative mortality. Postoperative complications and pain occur frequently and seriously affect the psychological status of patients. Esketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, has analgesic and antidepressant effects. In this study, we aim to investigate the effect of esketamine on postoperative depression and pain in patients undergoing PD.

METHODS/DESIGN

This prospective, single-center, randomized control trial will include 80 patients who will undergo elective PD. The patients will be randomly assigned to two groups: the experimental group that will receive esketamine (n = 40) and the control group (n = 40). In the esketamine group, the analgesic pump will be connected immediately after surgery. A solution of esketamine 1.5 mg/kg + sufentanil 2 µg/kg, diluted to 150 mL, will be administered continuously for 72 h at the background infusion and impact doses of 1 mL/h and 2 mL/time, respectively; the locking time will be 10 min. The control group will receive sufentanil 2 µg/kg that will be administered as per the esketamine group. The primary outcome will be the Hamilton Depression Scale (HAMD-17) score on the third day post-surgery (POD3). Secondary study indicators will include (1) visual analog scale (VAS) score and HAMD-17 score prior to surgery, immediately after entering the postanesthesia care unit (PACU) and 1, 2, 3, 4, and 5 days after surgery; (2) Richmond Agitation-Sedation Scale (RASS) score at 1, 2, 3, 4, and 5 days after surgery; (3) consumed doses of sufentanil and esketamine after surgery; (4) postoperative analgesia pump effective press times, rescue analgesia times, and rescue drug dosage, recording the number of rescue analgesia and rescue drug dosage at 6, 24, 48, and 72 h after the patient enters the PACU; (5) postoperative complications and adverse events; (6) postoperative hospital stay; (7) concentrations of brain-derived neurotrophic factor (BDNP), 5-hydroxytryptamine (5-HT), tumor necrosis factor (TNF-α) and interleukin-6, at 1, 3, and, 5 days post-surgery; and (8) the patient survival rate at 6 and 12 months post-surgery.

DISCUSSION

The study hypothesis is that the postoperative HAMD-17 and VAS scores, incidence of postoperative adverse reactions, and concentration of serum markers BDNP, 5-HT, TNF-α, and IL-6 in the experimental group will be lower than those in the control group.

TRIAL REGISTRATION

ClinicalTrials.gov ChiCTR2200066303. Registered on November 30, 2022.

PROTOCOL VERSION

1.0.

Low-dose esketamine with sufentanil for postcesarean analgesia in women with gestational diabetes mellitus: a prospective, randomized, double-blind study

Background

Pregnant women with gestational diabetes mellitus (GDM) require more analgesics after cesarean delivery than those who do not have GDM. Uncontrolled pain following cesarean delivery is a major problem in women with GDM. We investigate the efficacy of low-dose esketamine combined with sufentanil intravenous patient-controlled analgesia (PCA)for postcesarean analgesia in women with GDM.

Methods

One hundred forty pregnant women with GDM were enrolled participate in this randomized controlled trial and were randomized into two groups (70 in each group). The esketamine (S) group was given esketamine +sufentanil + ondansetron, and the control (C) group was given sufentanil +ondansetron. The primary outcome is sufentanil consumption at 24 hours postoperatively, the secondary outcomes are sufentanil consumption at 6 hours postoperatively, pain scores at 6, 24 and 48 hours postoperatively.

Results

Compared with group C, group S had significantly lower sufentanil consumption at 6 and 24 hours postoperatively (P= 0.049 and P<0.001), significantly lower activities VAS(pain during activities)scores at 6 hours postoperatively, rest and activities VAS (pain at rest and pain during activities)scores at 24 hours postoperatively, and activities VAS scores at 48 hours postoperatively(P=0.022, P =0.002, P=0.001 and P=0.007). Compared to group C, the time to bowel function return was significantly shorter in group S. There was no significant difference in rest VAS (pain at rest) scores at 6 and 48 hours postoperatively (P>0.05). The time to first lactation was not significantly different between the two groups (P>0.05). There was no significant difference in neonatal neurobehavioral scores between the two groups (P>0.05).

Conclusion

Compared to sufentanil PCA, adding low dose of esketamine significantly reduced the consumption of sufentanil while providing equally effective post cesarean analgesia in the patients with gestational diabetes.

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

Ketamine, a commonly used general anesthetic, can produce rapid and sustained antidepressant effect. However, the efficacy and safety of the perioperative application of ketamine on postoperative depression remains uncertain. We performed a meta-analysis to determine the effect of perioperative intravenous administration of ketamine on postoperative depression. Randomized controlled trials comparing ketamine with placebo in patients were included. Primary outcome was postoperative depression scores. Secondary outcomes included postoperative visual analog scale (VAS) scores for pain and adverse effects associated with ketamine. Fifteen studies with 1697 patients receiving ketamine and 1462 controls were enrolled. Compared with the controls, the ketamine group showed a reduction in postoperative depression scores, by a standardized mean difference (SMD) of -0.97, 95% confidence interval [CI, -1.27, -0.66], P < 0.001, I2 = 72% on postoperative day (POD) 1; SMD-0.65, 95% CI [-1.12, -0.17], P < 0.001, I2 = 94% on POD 3; SMD-0.30, 95% CI [-0.45, -0.14], P < 0.001, I2 = 0% on POD 7; and SMD-0.25, 95% CI [-0.38, -0.11], P < 0.001, I2 = 59% over the long term. Ketamine reduced VAS pain scores on POD 1 (SMD-0.93, 95% CI [-1.58, -0.29], P = 0.005, I2 = 97%), but no significant difference was found between the two groups on PODs 3 and 7 or over the long term. However, ketamine administration distinctly increased the risk of adverse effects, including nausea and vomiting (risk ratio [RR] 1.40, 95% CI [1.12, 1.75], P = 0.003, I2 = 30%), headache (RR 2.47, 95% CI [1.41, 4.32], P = 0.002, I2 = 19%), hallucination (RR 15.35, 95% CI [6.24, 37.34], P < 0.001, I2 = 89%), and dizziness (RR 3.48, 95% CI [2.68, 4.50], P < 0.001, I2 = 89%) compared with the controls. In conclusion, perioperative application of ketamine reduces postoperative depression and pain scores with increased risk of adverse effects.

The antidepressant actions of ketamine and its enantiomers

Ketamine, an N-methyl-d-aspartate receptor (NMDAR) antagonist first developed as an anesthetic, has shown significant promise as a medication with rapid antidepressant properties in treatment-resistant depression. However, concerns such as adverse side effects and potential misuse liability have limited its widespread use. Racemic ketamine has two enantiomers-(S)- and (R)-ketamine-that appear to have disparate underlying mechanisms. This brief review summarizes some of the most recent preclinical and clinical research regarding the convergent and divergent prophylactic, immediate, and sustained antidepressant effects of (S)- and (R)-ketamine while addressing potential differences in their side effect and misuse liability profiles. Preclinical research suggests divergent mechanisms underlying (S)- and (R)-ketamine, with (S)-ketamine more directly affecting mechanistic target of rapamycin complex 1 (mTORC1) signaling and (R)-ketamine more directly affecting extracellular signal-related kinase (ERK) signaling. Clinical research suggests that (R)-ketamine has a milder side effect profile than (S)-ketamine and decreases depression rating scale scores, but recent randomized, controlled trials found that it had no significant antidepressant efficacy compared to placebo, suggesting that caution is warranted in interpreting its therapeutic potential. Future preclinical and clinical research is needed to maximize the efficacy of each enantiomer, either by optimizing dose, route of administration, or administration paradigm.

Evaluation of clinical effects of Esketamine on depression in patients with missed miscarriage: A randomized, controlled, double-blind trial

BACKGROUND

Patients with missed miscarriages are usually accompanied by varying degrees of depression, which is closely related to the patient's prognosis. We investigated whether Esketamine could alleviate postoperative depression symptoms in patients with missed miscarriages who underwent painless curettage.

METHODS

This study was a randomized, parallel-controlled, double-blind, single-center trial. A total of 105 patients with preoperative 1d (EPDS) ≥ 10 were randomly assigned to the Propofol; Dezocine; Esketamine group. Patients record EPDS at 7 and 42 days after the operation. Secondary outcomes included VAS for 1 h postoperation, total propofol usage, adverse reactions, And the expressions of inflammatory factors of TNF-α, IL-1β, IL-6, IL-8, and IL-10.

RESULTS

Compared with the P and D group, patients in the S group had lower EPDS scores at 7 day (8.63 ± 3.14, 9.17 ± 3.23 vs. 6.34 ± 2.87 P = 0.0005) and 42 days (9.40 ± 2.67, 8.49 ± 3.05 vs.5.31 ± 2.49 P < 0.0001) after the operation. Respectively, Compared with the P group, the VAS scores (3.51 ± 1.12 vs. 2.80 ± 0.83, 2.40 ± 0.81, P = 0.0035) and the dosage of propofol used during operation (198.7 ± 47.48 vs. 145.5 ± 19.31, 142.9 ± 21.01 P < 0.0001) were lower in the D and S groups, and lower postoperative inflammatory response at 1 day after surgery. Other outcomes among the three groups were not found to the difference.

CONCLUSIONS

Esketamine effectively treated postoperative depressive symptoms of patients with a missed miscarriage, decreasing propofol consumption and inflammatory response.

Ketamine and the Disinhibition Hypothesis: Neurotrophic Factor-Mediated Treatment of Depression

Ketamine is a promising alternative to traditional pharmacotherapies for major depressive disorder, treatment-resistant depression, and other psychiatric conditions that heavily contribute to the global disease burden. In contrast to the current standard of care medications for these disorders, ketamine offers rapid onset, enduring clinical efficacy, and unique therapeutic potential for use in acute, psychiatric emergencies. This narrative presents an alternative framework for understanding depression, as mounting evidence supports a neuronal atrophy and synaptic disconnection theory, rather than the prevailing monoamine depletion hypothesis. In this context, we describe ketamine, its enantiomers, and various metabolites in a range of mechanistic actions through multiple converging pathways, including N-methyl-D-aspartate receptor (NMDAR) inhibition and the enhancement of glutamatergic signaling. We describe the disinhibition hypothesis, which posits that ketamine's pharmacological action ultimately results in excitatory cortical disinhibition, causing the release of neurotrophic factors, the most important of which is brain-derived neurotrophic factor (BDNF). BDNF-mediated signaling along with vascular endothelial growth factor (VEGF) and insulin-like growth factor 1 (IGF-1) subsequently give rise to the repair of neuro-structural abnormalities in patients with depressive disorders. Ketamine's efficacious amelioration of treatment-resistant depression is revolutionizing psychiatric treatment and opening up fresh vistas for understanding the underlying causes of mental illness.

Narrative Review: Low-Dose Ketamine for Pain Management

Pain is the leading cause of medical consultations and occurs in 50-70% of emergency department visits. To date, several drugs have been used to manage pain. The clinical use of ketamine began in the 1960s and it immediately emerged as a manageable and safe drug for sedation and anesthesia. The analgesic properties of this drug were first reported shortly after its use; however, its psychomimetic effects have limited its use in emergency departments. Owing to the misuse and abuse of opioids in some countries worldwide, ketamine has become a versatile tool for sedation and analgesia. In this narrative review, ketamine's role as an analgesic is discussed, with both known and new applications in various contexts (acute, chronic, and neuropathic pain), along with its strengths and weaknesses, especially in terms of psychomimetic, cardiovascular, and hepatic effects. Moreover, new scientific evidence has been reviewed on the use of additional drugs with ketamine, such as magnesium infusion for improving analgesia and clonidine for treating psychomimetic symptoms. Finally, this narrative review was refined by the experience of the Pain Group of the Italian Society of Emergency Medicine (SIMEU) in treating acute and chronic pain with acute manifestations in Italian Emergency Departments.

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

Importance

Epidural anesthesia is a primary choice for cesarean delivery, but supplemental analgesics are often required to relieve pain during uterine traction.

Objective

To investigate the sedative and analgesic effects of intravenous esketamine administered before childbirth via cesarean delivery with the patient under epidural anesthesia.

Design, Setting, and Participants

This multicenter, double-blind randomized clinical trial assessed 903 women 18 years or older who had full-term single pregnancy and were scheduled for elective cesarean delivery with epidural anesthesia in 5 medical centers in China from September 18, 2021, to September 20, 2022.

Intervention

Patients were randomized to receive intravenous injection of 0.25 mg/kg of esketamine or placebo before incision.

Main Outcomes and Measures

The coprimary outcomes included scores on the numeric rating scale of pain (an 11-point scale, with 0 indicating no pain and 10 indicating the worst pain; a difference of ≥1.65 points was clinically meaningful) and Ramsay Sedation Scale (a 6-point scale, with 1 indicating restlessness and 6 indicating deep sleep without response; a difference of ≥2 points was clinically meaningful) immediately after fetal delivery. Secondary outcomes included neonatal Apgar score assessed at 1 and 5 minutes after birth.

Results

A total of 600 women (mean [SD] age, 30.7 [4.3] years) were enrolled and randomized; all were included in the intention-to-treat analysis. Immediately after fetal delivery, the score on the numeric rating scale of pain was lower with esketamine (median [IQR], 0 [0-1]) than with placebo (median [IQR], 0 [0-2]; median difference, 0; 95% CI, 0-0; P = .001), but the difference was not clinically important. The Ramsay Sedation Scale scores were higher (sedation deeper) with esketamine (median [IQR], 4 [3-4]) than with placebo (median [IQR], 2 [2-2]; median difference, 2; 95% CI, 2-2; P < .001). The neonatal Apgar scores did not differ between the 2 groups at 1 minute (median difference, 0; 95% CI, 0-0; P = .98) and at 5 minutes (median difference, 0; 95% CI, 0-0; P = .27). Transient neurologic or mental symptoms were more common in patients given esketamine (97.7% [293 of 300]) than in those given placebo (4.7% [14 of 300]; P < .001).

Conclusions and Relevance

For women undergoing cesarean delivery under epidural anesthesia, a subanesthetic dose of esketamine administered before incision produced transient analgesia and sedation but did not induce significant neonatal depression. Mental symptoms and nystagmus were common but transient. Indications and the optimal dose of esketamine in this patient population need further clarification, but study should be limited to those who require supplemental analgesia.

Trial Registration

ClinicalTrials.gov Identifier: NCT04548973.

Effect of esketamine on postoperative depressive symptoms in patients undergoing thoracoscopic lung cancer surgery: A randomized controlled trial

Background

Depressive symptoms are common among patients with lung cancer. We aimed to assess the effects of esketamine on postoperative depressive symptoms after thoracoscopic lung cancer surgery.

Methods

In this randomized, double-blind, placebo-controlled trial, 156 patients undergoing thoracoscopic lung cancer surgery were randomly allocated in a 1:1 ratio to receive intravenous esketamine (intraoperatively and in patient-controlled analgesia until 48 h postoperatively) or normal saline placebo. The primary outcome was the proportion of patients with depressive symptoms at 1 month postoperatively, assessed using the Beck Depression Inventory-II (BDI-II). Secondary outcomes included depressive symptoms at 48 h postoperatively, hospital discharge and 3 months postoperatively, BDI-II scores, anxious symptoms, Beck Anxiety Inventory scores, Quality of Recovery-15 (QoR-15) scores, and 1- and 3-month mortality.

Main results

A total of 151 patients (75 in the esketamine group and 76 in the normal saline group) completed the 1-month follow-up. The esketamine group had a significantly lower incidence of depressive symptoms at 1 month compared to the normal saline group (1.3% vs. 11.8%; risk difference = −10.5, 95%CI = −19.6% to −0.49%; p = 0.018). After excluding patients without lung cancer diagnosis, the incidence of depressive symptoms was also lower in the esketamine group (1.4% vs. 12.2%; risk difference = −10.8, 95%CI = −20.2% to −0.52%; p = 0.018). The secondary outcomes were similar between groups, except that the esketamine group had higher QoR-15 scores at 1 month postoperatively (median difference = 2; 95%CI = 0 to 5; p = 0.048). The independent risk factors for depressive symptoms were hypertension (odds ratio = 6.75, 95%CI = 1.13 to 40.31; p = 0.036) and preoperative anxious symptoms (odds ratio = 23.83, 95%CI = 3.41 to 166.33; p = 0.001).

Conclusion

Perioperative administration of esketamine reduced the incidence of depressive symptoms at 1 month after thoracoscopic lung cancer surgery. History of hypertension and preoperative anxious symptoms were independent risk factors for depressive symptoms.

Clinical trial registration: Chinese Clinical Trial Registry http://www.chictr.org.cn, Identifier (ChiCTR2100046194).

Weapons of stress reduction: (R,S)-ketamine and its metabolites as prophylactics for the prevention of stress-induced psychiatric disorders

Exposure to stress is one of the greatest contributing factors to developing a psychiatric disorder, particularly in susceptible populations. Enhancing resilience to stress could be a powerful intervention to reduce the incidence of psychiatric disease and reveal insight into the pathophysiology of psychiatric disorders. (R,S)-ketamine and its metabolites have recently been shown to exert protective effects when administered before or after a variety of stressors and may be effective, tractable prophylactic compounds against psychiatric disease. Drug dosing, sex, age, and strain in preclinical rodent studies, significantly influence the prophylactic effects of (R,S)-ketamine and related compounds. Due to the broad neurobiological actions of (R,S)-ketamine, a variety of mechanisms have been proposed to contribute to the resilience-enhancing effects of this drug, including altering various transcription factors across the genome, enhancing inhibitory connections from the prefrontal cortex, and increasing synaptic plasticity in the hippocampus. Promisingly, select data have shown that (R,S)-ketamine may be an effective prophylactic against psychiatric disorders, such as postpartum depression (PPD). Overall, this review will highlight a brief history of the prophylactic effects of (R,S)-ketamine, the potential mechanisms underlying its protective actions, and possible future directions for translating prophylactic compounds to the clinic. This article is part of the Special Issue on 'Ketamine and its Metabolites'.

Epidural esketamine and morphine for postoperative analgesia after caesarean delivery: A pilot study

Objective

The aim of this study was to determine whether the addition of esketamine to morphine would improve postoperative analgesia after cesarean section.

Methods

Parturients who planned for a cesarean delivery using combined spinal-epidural anesthesia with a request for postoperative anesthesia were randomly divided into four groups (A, B, C, and D). When the surgery was completed, the parturients in groups A, B, C, and D were administered 2 mg morphine, 0.25 mg/kg of esketamine, 0.25 mg/kg of esketamine plus 2 mg morphine hydrochloride, and 0.25 mg/kg of esketamine plus 1 mg morphine through the epidural catheters, respectively. The postoperative pain at rest, pain with movement, the number of rescue analgesics, and adverse effects were evaluated for 48 h after cesarean delivery.

Results

A total of 119 parturients were included in this study, including 30 cases in group A, 30 cases in group B, 30 cases in group C, and 29 cases in group D. All visual analog scale (VAS) scores at rest and with movement were much lower in group C as compared with those in group A and group B (P < 0.05). Moreover, VAS scores at rest were also lower in Group C than in group D for 24 h (P < 0.05). Corresponding to the low pain scores, parturients in group C also required less rescue analgesia as compared with the other three groups (P = 0.021 for C vs. A, P < 0.001 for C vs. B, and P < 0.001 for C vs. D). There were no statistically significant differences between the four study groups with regard to the incidence of adverse events (P > 0.05).

Conclusions

The addition of esketamine to morphine improved postoperative analgesia after cesarean section without increasing the incidence of adverse events.

Effect of S-ketamine administered at the end of anesthesia on emergence delirium in preschool children undergoing tonsillectomy and/or adenoidectomy

Background: S-ketamine (the S-isomer of ketamine) is twice as potent as the racemic mixture of this agent and carries fewer side effects when administered to humans. Information regarding the use of S-ketamine for the prevention of emergence delirium (ED) is limited. Thus, we evaluated the effect of S-ketamine administered at the end of anesthesia on ED in preschool children undergoing tonsillectomy and/or adenoidectomy. Methods: We investigated 108 children aged 3-7 years, who were scheduled for elective tonsillectomy and/or adenoidectomy under general anesthesia. They were randomly assigned to receive either S-ketamine 0.2 mg/kg or an equal volume of normal saline at the end of anesthesia. The primary outcome was the highest score on the pediatric anesthesia ED (PAED) scale during the first 30 min post-surgery. The secondary outcomes included the incidence of ED (defined as a score of ≥ 3 on Aono scale), pain score, time to extubation, and incidences of adverse events. Multivariate analyses were also performed using logistic regression to evaluate the independent factors predictive of ED. Results: The median (interquartile range) PAED score of the S-ketamine group (0 [0, 3]) was significantly lower than that in the control group (1 [0, 7]) (estimate median difference = 0, 95% confidence interval -2 to 0, p = 0.040). Significantly fewer patients in the S-ketamine group had an Aono scale score ≥ 3 (4 [7%] vs. 12 [22%], p = 0.030). Patients in the S-ketamine group also had a lower median pain score than did control subjects (4 [4, 6] vs. 6 [5, 8], p = 0.002). The time to extubation and incidences of adverse events were comparable between the two groups. However, multivariate analyses indicated that except S-ketamine use, pain scores, age and duration of anesthesia were independent factors predictive of ED. Conclusion: S-ketamine (0.2 mg/kg) administered at the end of anesthesia effectively reduced the incidence and severity of ED in preschool children undergoing tonsillectomy and/or adenoidectomy without prolonging the time to extubation or increasing adverse events. However, S-ketamine use was not an independent factor predictive of ED.

Determining the effective dose of esketamine for mitigating pain during propofol injection by Dixon's up-and-down method: a double-blind, prospective clinical study of drug dose response

BACKGROUND

Propofol is an intravenous (IV) anesthetic medication widely used for procedural sedation, operative anesthesia, and in intensive care unit (ICU), but the incidence of pain during IV infusion can reach 28-90%. Ketamine can attenuate pain associated with IV propofol injection through local and central analgesic effects. Ketamine is gradually being transitioned to its S-enantiomer, esketamine, which has a similar mechanism of action. The purpose of our study is to determine the half effective dose (ED₅₀), 95% effective dose (ED₉₅), and 99% effective dose (ED₉₉) of esketamine for attenuating propofol injection pain using Dixon's up-and-down method to provide a reference for optimal dose selection for surgeries and procedures.

METHODS

Thirty gynecological patients undergoing hysteroscopic surgery were enrolled in a sequential method to determine the effective dose of esticketamine for analgesic propofol injection in order of operation. This study was based on the sequential allocation up-and-down rule designed by Dixon, and each patient was induced by esticketamine combined with propofol. During induction, the target dose of esketamine was first given via venous access in the left hand of the patient, and 30 s later, a fixed dose of 2 mg/kg (1 ml/s) of propofol was given. Patient perception of pain was scored with the verbal rating scale (VRS) every 5 s after the start of the propofol infusion, and the evaluation was stopped once the patient became unresponsive. The dosage of esketamine was increased or decreased up or down according to the patient's pain response. The initial dose of esketamine was 0.2 mg/kg, and the gradient of adjacent dose was 0.02 mg/kg. If the pain response assessment of the upper patient was positive (+), the dose of esselketamine in the next patient was increased by 0.02 mg/kg; if the pain response assessment of the upper patient was negative (-), the dose of esselketamine in the next patient was decreased by 0.02 mg/kg. The tests were carried out sequentially, with the pain response changing from positive to negative or from negative to positive, and the tests were stopped after at least 6 crossover points, and the effective dose of esticketamine was calculated using probit probability regression analysis.

RESULTS

The ineffective group comprised patients with a positive pain response and the effective group comprised patients with a negative pain response. The 95% CI was set as the confidence interval of effective dose ED value，and we found esketamine's ED₅₀ = 0.143 mg/kg (0.120, 0.162 mg/kg), ED₉₅ = 0.176 mg/kg (0.159, 0.320 mg/kg), and ED₉₉ = 0.189 mg/kg (0.167, 0.394 mg/kg). The esketamine dose and VRS score during propofol injection were significantly different between the two groups (P < 0.05), whereas surgical duration, emergence time, visual analogue scale (VAS) score of postoperative uterine contraction pain, and Riker sedation/anxiety scale (SAS) score were not significantly different. Bradycardia occurred in only one patient during anesthesia induction, while hemodynamics was stable in the rest of the patients without obvious adverse reactions.

CONCLUSION

Small doses of esketamine combined with propofol can be safely and effectively used for hysteroscopic surgery. We recommended a dose of 0.2 mg/kg IV esketamine before induction of anesthesia to reduce the pain of propofol injection.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2100048951. Date of registration: July 19, 2021.

Efficacy of ketamine for comorbid depression and acute or chronic pain: A systematic review

Pain and depression frequently co-occur. Due to its antidepressant and analgesic properties, ketamine has been used for the management of treatment-resistant depression and pain. This systematic review examined the literature on the efficacy of sub-anesthetic doses of ketamine in individuals experiencing comorbid depression and chronic pain (CDCP), as well as comorbid depression and acute pain (CDAP). A secondary objective was to provide an assessment of dosage, route, and adverse effects of ketamine treatment for CDCP and CDAP. A literature search was conducted on MEDLINE, PsycINFO, and Embase databases, coupled with a manual screening of the bibliography sections of included articles. In addition, registered ongoing and planned trials were searched on Clinicaltrials.gov. The end date of the search was April 9th, 2022. Included studies assessed changes in depression and pain in patients receiving at least one sub-anesthetic dose of ketamine. Assessment of quality was conducted using the GRADE checklist. Of the 7 CDCP clinical trials, 3 reported a reduction in depression and pain, 3 reported a reduction in depression or pain only, and 1 reported no improvement in either comorbidity. Among the 7 CDAP clinical trials, 4 studies found improvements in depression and pain while the remaining 3 reported improvements in only one parameter. Ten of the 12 case studies and 2 of the 3 observational studies assessing CDCP and CDAP found improvements in pain and depression scores post-treatment with effects of variable duration. The planned methodologies of the registered clinical trials are in line with those of the published research. Preliminary evidence supports the efficacy of ketamine in treating CDCP and CDAP. However, the current review identified a small number of heterogeneous studies with mixed results, preventing comprehensive conclusions. More longitudinal placebo-controlled studies are needed to identify the effects of ketamine for patients with CDCP and CDAP.

Subanaesthetic dose of esketamine during induction delays anaesthesia recovery a randomized, double-blind clinical trial

BACKGROUND

Esketamine is an antagonist of the N-methyl-D-aspartate receptor (NMDA receptor) that is widely used for multimodal analgesia. In addition to analgesia, sedation is another important effect of esketamine. However, data are limited regarding the sedation effect of esketamine during general anaesthesia. The objective of this study was to determine whether sedation with a subanaesthetic does of esketamine affects anaesthesia recovery.

METHODS

Fifty patients, ASA I to II patient scheduled to laparoscopic cholecystectomy, were randomly assigned to receive a single bolus of esketamine 0.2 mg kg-1 (esketamine group) or placebo (control group). Propofol, sufentanil and rocuronium were used during total intravenous anaesthesia. The patients' time of recovery from anaesthesia, postoperative pain, postoperative nausea and vomiting, and postoperative agitation were analysed.

RESULTS

Data from 47 patients were analysed. The average time of anaesthetic recovery was 22.04 ± 1.48 min in the esketamine group(n = 23) and 17.54 ± 1.46 min in the control group(n = 24). The recovery time was significantly longer in the esketamine group. Postoperative pain in the PACU was lower in the esketamine group (NRS score range 0-2) than in the control group (NRS score range 0-3). There were no differences in postoperative nausea and vomiting, and postoperative agitation.

CONCLUSION

Subanaesthetic doses of esketamine can reduce postoperative pain in the PACU but delay the aesthetic recovery during the laparoscopic cholecystectomy, without affecting postoperative nausea and vomiting, and postoperative agitation.

TRIAL REGISTRATION

The study was registered at the Chinese Clinical Trial Registry http://www.chictr.org.cn/ (Registration date: 20/11/2020; TrialID: ChiCTR2000040077 ).

Ketamine as a prophylactic resilience-enhancing agent

Stress exposure is one of the greatest risk factors for psychiatric illnesses, including major depressive disorder (MDD) and posttraumatic stress disorder (PTSD). Enhancing stress resilience could potentially protect against the development of stress-induced psychiatric disorders, yet no resilience-enhancing pharmaceuticals have been developed to date. This review serves to consider the existing evidence for a potential pro-resilience effect of ketamine in rodents as well as the preliminary evidence of ketamine as a prophylactic treatment for postpartum depression (PPD) in humans. Several animal studies have demonstrated that ketamine administered 1 week prior to a stressor (e.g., chronic social defeat and learned helplessness) may protect against depressive-like behavior. A similar protective effect has been demonstrated against PTSD-like behavior following Contextual Fear Conditioning (CFC). Recent work has sought to explore if the administration of ketamine prevented the development of postpartum depression (PPD) in humans. Researchers administered ketamine immediately following caesarian-section and found a significantly reduced prevalence of PPD in the ketamine-treated groups compared to the control groups. Utilizing ketamine as a resilience-enhancing treatment may have unique applications, including leading to a deeper understanding of the neurobiological mechanism underlying resilience. Future trials aiming to translate and replicate these findings with humans are warranted.