s-ketamine enhances thalamocortical and corticocortical synaptic transmission in acute murine brain slices via increased AMPA-receptor-mediated pathways

Safety and efficacy of low-dose esketamine in laparoscopic cholecystectomy: a prospective, double-blind randomized controlled trial

BACKGROUND

Esketamine, recognized for its analgesic, sedative, and anti-inflammatory qualities, is integral in multimodal analgesia. However, the potential opioid-sparing effects of intravenous esketamine, along with its impact on inflammatory responses, and cognitive function during laparoscopic surgery, remain unexplored.

METHODS

In this study, 90 patients scheduled for laparoscopic cholecystectomy were equally randomized into three groups: a normal saline control group (NS), a low-dose esketamine group (LS) and a high-dose esketamine group (HS). Subsequently, we monitored several parameters: hemodynamics, levels of stress and inflammatory responses, intraoperative doses of sufentanil, remifentanil, and propofol, and 24-hour postoperative sufentanil requirements. We also evaluated alterations in cognitive function, perioperative indicators, and potential adverse reactions among the three groups.

RESULTS

Compared to their levels 5 minutes prior to anesthesia (T0) and 30 minutes post-operation (T4), the NS group exhibited a more significant decrease in Mean Arterial Pressure (MAP) and Heart Rate (HR) at various time intervals: 5 minutes after the skin incision (T1), 30 minutes post-incision (T2), and at the conclusion of the operation (T3), compared to the LS and HS groups(P < 0.05). Furthermore, the NS group exhibited a greater increase in levels of adrenaline (AD), noradrenaline (NE), endothelin (ET), C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) at T1, T2, and T3, more so than the other two groups(P < 0.05). 24 hours after the surgery, patients in the LS group and HS group had significantly higher Montreal Cognitive Assessment (MoCA) scores than those in the NS group(P < 0.05). The LS and HS groups required lower doses of propofol, remifentanil, and sufentanil during surgery (P < 0.05), experienced shorter postoperative recovery times, and had lower incidences of nausea, vomiting, and respiratory depression compared to the NS group (P < 0.05).

CONCLUSION

The administration of low-dose esketamine has been shown to be safe, effective, and dependable in the context of laparoscopic gallbladder surgery. It has the capacity to stabilize hemodynamic responses, ameliorate both stress and inflammatory reactions from surgery, and hastens anesthesia recovery. Furthermore, it fosters the restoration of postoperative cognitive function. Notably, when combined with nalbuphine, it exhibits opioid-sparing effects, reducing postoperative adverse outcomes.

TRIAL REGISTRATION

The trial is registered with the China Clinical Trials Registry Registration Number: ChiCTR2300067596. Retrospectively registered (date of registration: 12/01/2023).

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.