Perioperative utility of amisulpride and dopamine receptor antagonist antiemetics-a narrative review

Despite advances in antiemetics and protocolized postoperative nausea vomiting (PONV) management, it remains one of the most common postoperative adverse events. In patients who developed PONV despite antiemetic prophylaxis, giving a rescue treatment from the same class of medication is known to be of limited efficacy. Given the widespread use of 5-HT3 antagonists as PONV prophylaxis, another class of effective intravenous rescue antiemetic is in dire need, especially when prophylaxis fails, and rescue medication is utilized. Dopamine antagonists were widely used for the treatment of PONV but have fallen out of favor due to some of their side effect profiles. Amisulpride was first designed as an antipsychotic medication but was found to have antiemetic properties. Here we will review the historical perspective on the use of dopamine receptor antagonist antiemetics, as well as the evidence on the efficacy and safety of amisulpride

The validity and applications of the analgesia nociception index: a narrative review

Pain refers to the subjective, unpleasant experience that is related to illness or injury. In contrast to pain, nociception refers to the physiological neural processing of noxious stimuli, such as intra-operative surgical stimuli. One novel device, the Analgesia Nociception Index (ANI), aims to objectively measure intra-operative nociception by analyzing the heart rate variability in patients undergoing surgery. Through this method of nociceptive monitoring, the ANI device aims to provide an objective, continuous evaluation of patient comfort levels and allow anesthesiologists to better manage surgical stress and patient analgesia, perhaps with even better efficacy than current practices used to assess nociception. Additionally, ANI may have clinical application in settings outside of the operating room, such as in the intensive care unit. In this narrative review, we compiled and summarized the findings of many studies that have investigated ANI's validity and applications in different clinical settings. Currently, the literature appears mostly supportive of ANI's ability to detect nociception in both surgical and non-surgical settings. However, the ability for ANI to provide clinical benefits, such as decreased intra-operative opioid use, post-operative opioid use, and post-operative pain compared to standard practices appear controversial. Because of the wide variety of methodology, clinical settings, patient populations, and limitations in these studies, more investigation of ANI is needed before any firm conclusions can be drawn on its clinical benefits

Caudal block vs. transversus abdominis plane block for pediatric surgery: a systematic review and meta-analysis

BackgroundThe caudal block and transversus abdominis plane block (TAP) are commonly used in combination with general anesthesia for pediatric lower abdominal, inguinal, and genitourinary surgeries. There is limited data directly comparing the impact of these techniques on recovery. In this meta-analysis, we compare the duration of postoperative analgesia between these two techniques.ObjectiveThis review examined the duration of analgesia in pediatric patients (age 0–18 years) undergoing surgery who received caudal or TAP block after induction of general anesthesia. The primary outcome was duration of analgesia, defined as the time to first rescue analgesic dose. Secondary outcomes included number of rescue analgesic doses, acetaminophen usage within 24 h postoperatively, 24 h pain score area under the curve, and postoperative nausea and vomiting.Evidence reviewWe systematically searched Pubmed, Central, EMBASE, CINAHL, Google Scholar, Web of Science citation index, the US clinical trials register, and abstracts from prominent 2020–2022 anesthesia conferences for randomized controlled trials that compared these blocks and reported analgesia duration.FindingsTwelve RCTs inclusive of 825 patients were identified. TAP block was associated with longer analgesia duration (Mean difference = 1.76 h, 95% CI: 0.70–2.81, p = 0.001) and reduced doses of rescue analgesic within 24 h (Mean difference = 0.50 doses, 95% CI: 0.02–0.98, p = 0.04). No statistically significant differences were detected in other outcomes.ConclusionThis meta-analysis suggests that TAP block provides greater duration of analgesia than caudal block after pediatric surgeries. TAP block was also associated with fewer rescue analgesic doses in the first 24 h without increased pain scores.Systematic review registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?RecordID=380876, identifier: CRD42022380876

Anesthesia, the developing brain, and dexmedetomidine for neuroprotection

Anesthesia-induced neurotoxicity is a set of unfavorable adverse effects on central or peripheral nervous systems associated with administration of anesthesia. Several animal model studies from the early 2000’s, from rodents to non-human primates, have shown that general anesthetics cause neuroapoptosis and impairment in neurodevelopment. It has been difficult to translate this evidence to clinical practice. However, some studies suggest lasting behavioral effects in humans due to early anesthesia exposure. Dexmedetomidine is a sedative and analgesic with agonist activities on the alpha-2 (ɑ2) adrenoceptors as well as imidazoline type 2 (I2) receptors, allowing it to affect intracellular signaling and modulate cellular processes. In addition to being easily delivered, distributed, and eliminated from the body, dexmedetomidine stands out for its ability to offer neuroprotection against apoptosis, ischemia, and inflammation while preserving neuroplasticity, as demonstrated through many animal studies. This property puts dexmedetomidine in the unique position as an anesthetic that may circumvent the neurotoxicity potentially associated with anesthesia

Pairing symmetry and properties of iron-based high temperature superconductors

Pairing symmetry is important to indentify the pairing mechanism. The analysis becomes particularly timely and important for the newly discovered iron-based multi-orbital superconductors. From group theory point of view we classified all pairing matrices (in the orbital space) that carry irreducible representations of the system. The quasiparticle gap falls into three categories: full, nodal and gapless. The nodal-gap states show conventional Volovik effect even for on-site pairing. The gapless states are odd in orbital space, have a negative superfluid density and are therefore unstable. In connection to experiments we proposed possible pairing states and implications for the pairing mechanism.Comment: 4 pages, 1 table, 2 figures, polished versio

Fault model of the 2017 Jiuzhaigou Mw 6.5 earthquake estimated from coseismic deformation observed using Global Positioning System and Interferometric Synthetic Aperture Radar data

Abstract On August 8, 2017, the Jiuzhaigou Mw 6.5 earthquake occurred in Sichuan province, southwestern China, along the eastern margin of the Tibetan Plateau. The epicenter is surrounded by the Minjiang, Huya, and Tazang Faults. As the seismic activity and tectonics are very complicated, there is controversy regarding the accurate location of the epicenter and the seismic fault of the Jiuzhaigou earthquake. To investigate these aspects, first, the coseismic deformation field was derived from Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) measurements. Second, the fault geometry, coseismic slip model, and Coulomb stress changes around the seismic region were calculated using a homogeneous elastic half-space model. The coseismic deformation field derived from InSAR measurements shows that this event was mainly dominated by a left-lateral strike-slip fault. The maximal and minimal displacements were approximately 0.15 m and − 0.21 m, respectively, along line-of-sight observation. The whole deformation field follows a northwest-trending direction and is mainly concentrated west of the fault. The coseismic slip is 28 km along the strike and 18 km along the dip. It is dominated by a left-lateral strike-slip fault. The average and maximal fault slip is 0.18 and 0.85 m, respectively. The rupture did not fully reach the ground surface. The focal mechanism derived from GPS and InSAR data is consistent with the kinematics and geometry of the Huya Fault. Therefore, we conclude that the northern section or the Shuzheng segment of the Huya Fault is the seismogenic fault. The maximal fault slip is located at 33.25°N and 103.82°E at a depth of ~ 11 km, and the release moment is approximately 6.635 × 1018 Nm, corresponding to a magnitude of Mw 6.49, which is consistent with results reported by the US Geological Survey, Global Centroid Moment Tensor, and other researchers. The coseismic Coulomb stress changes enhanced the stress on the northwest and southeast edges of the northern extension of the Huya Fault. Seismic risks cannot be ignored in the future although aftershocks are fewer in number in these regions

Surgery, neuroinflammation and cognitive impairmentResearch in context

Trauma experienced during surgery can contribute to the development of a systemic inflammatory response that can cause multi-organ dysfunction or even failure. Post-surgical neuroinflammation is a documented phenomenon that results in synaptic impairment, neuronal dysfunction and death, and impaired neurogenesis. Various pro-inflammatory cytokines, such as TNFα, maintain a state of chronic neuroinflammation, manifesting as post-operative cognitive dysfunction and post-operative delirium. Furthermore, elderly patients with post-operative cognitive dysfunction or delirium are three times more likely to experience permanent cognitive impairment or dementia. We conducted a narrative review, considering evidence extracted from various databases including Pubmed, MEDLINE and EMBASE, as well as journals and book reference lists. We found that further pre-clinical and well-powered clinical studies are required to delineate the precise pathogenesis of post-operative delirium and cognitive dysfunction. Despite the burden of post-operative neurological sequelae, clinical studies investigating therapeutic agents, such as dexmedetomidine, ibuprofen and statins, have yielded conflicting results. In addition, evidence supporting novel therapeutic avenues, such as nicotinic and HMGB-1 targeting and remote ischaemic pre-conditioning, is limited and necessitates further investigation. Keywords: Inflammation, Neuroinflammation, Surgery, Systemic inflammatory response syndrome, Multiple organ dysfunction syndrome, Therapeutic target