Anesthetic Adjunct Research Articles

ENHANCING SPINAL ANESTHESIA WITH DEXMEDETOMIDINE: A PROSPECTIVE STUDY ON PROLONGING ANALGESIA AND REDUCING OPIOID REQUIREMENTS IN INFRA UMBILICAL SURGERIES

Objective: Pain management in surgical settings poses significant challenges, particularly in minimizing opioid use due to associated risks. Dexmedetomidine, a selective α2-adrenergic agonist, has shown promise as an adjunct in spinal anesthesia to enhance analgesic and anesthetic effects. Methods: This prospective, randomized, double-blind study involved 60 patients undergoing infraumbilical surgeries, divided into two groups. Group D received intravenous dexmedetomidine, while Group C received a saline placebo. We assessed the duration of sensory and motor blocks, sedation levels, and the time to first postoperative analgesia request. Results: Group D exhibited significantly longer durations of sensory and motor blocks, higher sedation scores, and extended time before requesting postoperative analgesia compared to Group C. These results suggest improved anesthetic quality and pain control with dexmedetomidine. Conclusion: Intravenous dexmedetomidine enhances spinal anesthesia by prolonging block durations and improving sedation, potentially decreasing the need for postoperative opioids. This supports its use as an effective adjunct in anesthesia, contributing to safer, more effective pain management strategies.

Safety and efficacy of Dexmedetomidine in preoperative and postoperative settings during transsphenoidal resection of pituitary Adenoma: A systematic review and meta-analysis of randomized controlled trials

Background Pituitary adenoma, a benign tumor of the pituitary gland, represents 10-15% of intracranial tumors. Although non-cancerous, its size and location can cause significant health issues, including hormonal imbalances and compression of nearby structures like the optic chiasm, leading to conditions such as Cushing’s disease, acromegaly, and visual disturbances. The prevalence ranges from 46 to 95 per 100,000 individuals. This study evaluates the effectiveness and safety of dexmedetomidine versus placebo in patients undergoing transsphenoidal resection of pituitary adenomas. Methods A systematic review and meta-analysis following PRISMA guidelines included 10 RCTs with 633 patients. English-language RCTs were sourced from PubMed, Scopus, Web of Science, Google Scholar, and Cochrane Library. Risk of bias was assessed using the ROB2 tool, and statistical analyses were performed using RevMan 5.3. Results Dexmedetomidine significantly reduced heart rate after intubation (MD: -6.61 bpm, 95% CI: -8.98 to -4.24, p < 0.00001) and post-extubation (MD: -6.77 bpm, 95% CI: -8.59 to -4.96, p < 0.00001). Mean arterial pressure decreased after intubation (MD: -10.49 mmHg, 95% CI: -12.73 to -8.26, p < 0.00001) and post-extubation (MD: -12.97 mmHg, 95% CI: -14.37 to -11.57, p < 0.00001). Dexmedetomidine also reduced surgical duration (SMD: -0.23, 95% CI: -0.41 to -0.05, p = 0.01), blood loss (MD: -109.49 mL, 95% CI: -152.60 to -66.38, p < 0.00001), propofol dose (SMD: -1.04, 95% CI: -1.72 to -0.37, p = 0.002), extubation time (SMD: -0.70, 95% CI: -0.93 to -0.47, p < 0.00001), and postoperative nausea and vomiting (OR: 0.45, 95% CI: 0.25 to 0.80, p = 0.007). Conclusions Dexmedetomidine enhances perioperative outcomes in transsphenoidal resection of pituitary adenomas, supporting its use as an effective anesthetic adjunct.

Anesthetic Gases: Environmental Impacts and Mitigation Strategies for Fluranes and Nitrous Oxide

Anesthetic gases represent a small but significant portion of the environmental impact of health care in many countries. These compounds include several fluorocarbons commonly referred to as “fluranes”. The fluranes are greenhouse gases (GHG) with global warming potentials in the hundreds to thousands and are also PFAS compounds (per- and polyfluorinated alkyl substances) according to at least one definition. Nitrous oxide (N2O) is sometimes used as an adjunct in anesthesia, or for sedation, but has a significant stratospheric ozone depletion potential as well as GHG effects. Reducing emissions of these compounds into the environment is, therefore, a growing priority in the health care sector. Elimination or substitution of the highest impact fluranes with alternatives has been pursued with some success but limitations remain. Several emission control strategies have been developed for fluranes including adsorption onto solids, which has shown commercial promise. Catalytic decomposition methods have been pursued for N2O emission control, although mixtures of fluranes and N2O are potentially problematic for this technology. All such emission control technologies require the effective scavenging and containment of the anesthetics during use, but the limited available information suggests that fugitive emissions into the operating room may be a significant route for unmitigated losses of approximately 50% of the used fluranes into the environment. A better understanding and quantification of such fugitive emissions is needed to help minimize these releases. Further cost–benefit and techno-economic analyses are also needed to identify strategies and best practices for the future.

A COMPARISON OF 0.5% BUPIVACAINE ALONE VERSUS 0.5% BUPIVACAINE WITH VERAPAMIL AS AN ADJUNCT IN ULTRASOUND-GUIDED SUPRACLAVICULAR BRACHIAL PLEXUS BLOCK

Objective: Supraclavicular brachial plexus blocks are commonly performed for surgeries on the upper limb because they are highly effective for both anesthesia during the procedure and pain control afterward. This method targets the entire brachial plexus, making it a popular alternative to general anesthesia, as it minimizes associated risks while offering better pain relief after the surgery. Bupivacaine, a long-lasting local anesthetic, is often preferred for this block, though its pain-relieving effects eventually wear off. Owing to limitations regarding the duration of analgesia, many adjuncts have been tried since time immemorial to enhance the effectiveness of the blocking properties of these local anesthetics. Verapamil, a calcium channel blocker, has emerged as a promising adjunct that can potentially enhance and prolong the effects of Bupivacaine. This study aims to compare the efficacy of 0.5% Bupivacaine alone versus Bupivacaine combined with Verapamil in ultrasound-guided supraclavicular brachial plexus blocks. Methods: A randomized clinical trial was conducted on patients undergoing elective upper limb surgeries under ultrasound-guided supraclavicular brachial plexus block. Group A received 30 mL of 0.5% Bupivacaine, whereas Group B received 30 mL of 0.5% Bupivacaine with 5 mg of Verapamil. Primary outcomes included the time of onset of sensory and motor blockade and the duration of analgesia for the same, whereas secondary outcomes included post-operative pain scores and hemodynamic stability. Results: The addition of Verapamil to Bupivacaine significantly accelerated the onset of sensory and motor blockade in Group B compared to Group A. Group B also exhibited a significantly prolonged duration of both sensory and motor blockade and reduced post-operative analgesic requirements. Conclusion: Verapamil helps boost the effectiveness of Bupivacaine in supraclavicular brachial plexus blocks, speeding up the onset of its actions and extending its pain-relieving effects. This makes it a useful addition to local anesthetics, making it a valuable adjunct in regional anesthesia.

Combination of different local anesthetic adjunct for supraclavicular brachial plexus block after arthroscopic shoulder surgery: a prospective randomized controlled trial

BackgroundAcute pain is a major concern after arthroscopic shoulder surgery, supraclavicular brachial plexus blockade has shown favorable postoperative analgesic effects. However, its duration of analgesia does not meet clinical needs. We aimed to explore whether the combination of different local anesthetic adjunct can prolong the analgesic duration of supraclavicular brachial plexus block for arthroscopic shoulder surgery.MethodsIn this prospective randomized controlled trial, we allocated 80 patients into four groups: Group DMD (dexamethasone 10 mg + ropivacaine 100 mg + dexmedetomidine 50 µg + magnesium sulfate 250 mg), Group DM (ropivacaine 100 mg + dexmedetomidine 50 µg + magnesium sulfate 250 mg), Group M (ropivacaine 100 mg + magnesium sulfate 250 mg) and Group D (ropivacaine 100 mg + dexmedetomidine 50 µg). The primary outcome was the time to first request for analgesia. Secondary outcome measures included cumulative opioid consumption at 6, 12, 18, 24, and 48 h postoperatively, VAS scores at 6, 12, 18, 24, and 48 h postoperatively and so on.ResultsThe time to first request for analgesia in Group DMD was significantly longer than Group DM (P = 0.011) and Group M (P = 0.003). The cumulative opioid consumption at 18 h postoperatively in Group DMD was significantly lower than in Group DM (P = 0.002) and Group M (P = 0.007). The cumulative opioid consumption at 24 h postoperatively in Group DMD was significantly lower than in Group DM (P = 0.016). The VAS score at 6 h postoperatively in Group DMD was significantly lower than in Group DM and Group M. The VAS score at 12 h postoperatively in Group DMD was significantly lower than in Group M. For American Shoulder and Elbow Surgeons Score, Group DMD had a better score than Group DM and Group D.ConclusionsThe analgesic efficacy of supraclavicular brachial plexus blockade combined with dexamethasone, magnesium sulfate, and dexmedetomidine is significantly superior to the combination of magnesium sulfate and dexmedetomidine, and significantly superior to the use of magnesium sulfate alone.Trial registrationThis trial was registered in Chinese Clinical Trial Registry. (ChiCTR2200061181, Date of registration: June 15, 2022, http://www.chictr.org.cn)

Alleviation effects of dexmedetomidine on myocardial ischemia/reperfusion injury through fatty acid metabolism pathway via Elovl6

Dexmedetomidine (Dex) is widely used in the sedation in intensive care units and as an anesthetic adjunct. Considering the anti-inflammatory and antioxidant properties of Dex, we applied in vivo rat model as well as in vitro cardiomyocyte models (embryonic rat cardiomyocytes H9c2 cells and neonatal rat cardiomyocytes, NRCMs) to evaluate the effects of Dex against myocardial ischemia reperfusion (I/R) injury. Transcriptomic sequencing for gene expression in heart tissues from control rats and Dex-treated rats identified that genes related to fatty acid metabolism were significantly regulated by Dex. Among these genes, the elongation of long-chain fatty acids (ELOVL) family member 6 (Elovl6) was most increased upon Dex-treatment. By comparing the effects of Dex on both wild type and Elovl6-knockdown H9c2 cells and NRCMs under oxygen-glucose deprivation/reoxygenation (OGD/R) challenge, we found that Elovl6 knockdown attenuated the protection efficiency of Dex, which was supported by the cytotoxicity endpoints (cell viability and lactate dehydrogenase release) and apoptosis as well as key gene expressions. These results indicate that Dex exhibited the protective function against myocardial I/R injury via fatty acid metabolism pathways and Elovl6 plays a key role in the process, which was further confirmed using palmitate exposure in both cells, as well as in an in vivo rat model. Overall, this study systematically evaluates the protective effects of Dex on the myocardial I/R injury and provides better understanding on the fatty acid metabolism underlying the beneficial effects of Dex.

The Impact of Ketamine-Based Versus Non-Ketamine-Based ECT Anesthesia Regimens on the Severity of Patients’ Depression and Occurrence of Adverse Events: A Systematic Review with Meta-Analysis

Objective: To compare efficacy and safety outcomes for ketamine anesthesia + electroconvulsive therapy (ECT) versus nonketamine anesthesia + ECT in treatment-resistant depression (TRD) patients. Data Sources: PubMed and Embase were searched from the earliest date through November 27, 2023. Study Selection and Data Extraction: Relevant randomized controlled trials (RCTs) of ketamine + ECT versus nonketamine anesthesia + ECT that reported data on remission (odds ratio [OR]), defined as a Hamilton Depression Rating Scale (HAM-D) and Montgomery-Asburg Depression Rating Scale (MADRS) score <8-10) and mean differences (MDs) in HAM-D scores after several ECT sessions were compared using inverse variance methods. The risk of bias (RoB) was assessed using the Cochrane RoB tool. Data Synthesis: Seventeen RCTs (RoB: Low N = 12, Moderate N = 2, High N = 3) with 1181 total patients met inclusion criteria. Patients receiving ECT experienced greater clinical remission (OR: 1.78, [95% confidence interval (CI): 1.08-2.93], I2 = 11%, N = 9) and lower HAM-D scores after the third through sixth ECT sessions as well as the eighth ECT session when ketamine versus nonketamine anesthesia was used. Ketamine use with ECT significantly increased fear with hallucinations (OR: 1.99, [95% CI: 1.11-3.58], I2 = 0%, N = 7) than with nonketamine anesthesia. Relevance to Patient Care and Clinical Practice: Selecting ketamine-based anesthesia could more quickly and profoundly enhance the beneficial effects of ECT for patients with severe TRD, but the balance of benefits to harm is unclear as there may be additional adverse events. Conclusion: Ketamine is a promising anesthesia adjunct to ECT that may enhance antidepressant effects in exchange for more adverse events.

Serum Levels of Bupivacaine After Bilateral Ultrasound-Guided Deep Parasternal Intercostal Plane Block in Cardiac Surgery with Median Sternotomy

To evaluate systemic levels of bupivacaine after bilateral ultrasound-guided deep parasternal intercostal plan (PIP) block in cardiac surgical patients undergoing median sternotomy. Prospective, observational study SETTING: Single institution; academic university hospital PARTICIPANTS: Twenty-eight adult patients undergoing cardiac surgery with median sternotomy received a PIP block with 2.5 mg/kg bupivacaine with or without dexamethasone and dexmedetomidine. Arterial blood samples were analyzed for total serum bupivacaine concentration at 5, 15, 30, 45, 60, 90, 120, and 150 minutes after placement of PIP. Local anesthetic volume, local anesthetic adjuncts, time to extubation, postoperative pain scores, and opioid consumption were recorded. The mean peak bupivacaine concentration was 0.60 ± 0.62 µg/mL, and the mean time to maximum concentration (Tmax) was 16.92 ± 12.97 minutes. Two patients (7.1%) had a concentration >2.0 µg/mL within 15 minutes of block placement. The mean Tmax of bupivacaine was significantly greater in patients who did not receive additives compared to those patients who did (22.86 ± 14.77 minutes v 10.0 ± 5.22 minutes; p = .004). The times to extubation and postoperative pain were not improved with additives. Bilateral PIP placed at the end of cardiac surgery resulted in low systemic bupivacaine levels. The inclusion of additives shortened Tmax without improving outcome.

Impact of dexmedetomidine use on pediatric PACU length of stay and practice patterns: A single center study

BackgroundDexmedetomidine has been increasingly incorporated in pediatric anesthesia owing to its opioid sparing analgesic effect. In theory, dexmedetomidine may lower the use of intraoperative and postoperative opioids but increase post anesthesia care unit (PACU) patient recovery time. In 2020, the Anesthesia Department of Albany Medical Center implemented an opioid reducing initiative with dexmedetomidine incorporation as a major strategy. As such, we have carried out this retrospective study to examine the effect of dexmedetomidine on pediatric PACU length of stay (LOS) across a blend of invasive surgical procedures requiring general anesthesia. MethodsThe present study is a single-institution, retrospective chart review of children undergoing invasive procedures requiring general anesthesia at an academic center during 2021 and 2022. Convenience sampling of the first 200 patients from each of those years was analyzed (n=400). Here, we compared PACU LOS between patients who did or did not receive dexmedetomidine using the propensity-score matching treatment effects analysis. We also examined changes in perioperative medication patterns between patients who did versus did not receive dexmedetomidine. Results344 patients over the study period met inclusion criteria. The matched cohort consisted of 118 patients without dexmedetomidine administration and 122 patients with dexmedetomidine administration. The average treatment effect for administration of dexmedetomidine was an increase in PACU LOS of 19.4 min (p < 0.001). Dosages and proportion of patients receiving intraoperative or postoperative opioids did not significantly change during the study period. ConclusionsIn our center, dexmedetomidine use in pediatric procedures with general anesthesia was associated with prolonged recovery times, without a corresponding reduction in opioid use. Further investigations are therefore warranted to understand the role of dexmedetomidine as an anesthetic adjunct and in multimodal pain management.

Are We Depleted of Research Questions in Regional Anaesthesia?

Regional anaesthesia has significantly evolved, shaping pain management in surgery. This article examines whether research question in this field are becoming exhausted, or if new avenues remain unexplored. Key trends include the integration of ultrasound guidance for precision, optimizing drug combinations for enhanced safety and efficacy, and focusing on patient-concerned outcomes to improve satisfaction and recovery. Tailored approaches for special populations and long-term safety studies are also crucial. Future research may explore innovations in drug delivery, novel local anaesthetic adjuncts, neurostimulation techniques, global access, interdisciplinary collaborations, and the application of artificial intelligence. Emphasizing simplicity, innovation, and patient centric care will ensure continued progress in regional anaesthesia, fostering advancement that enhance both scientific knowledge and clinical practices. Keywords: Pain management, Regional anaesthesia, Research trends

Intra-operative anesthetic induced myocardial protection during cardiothoracic surgery: a literature review.

Myocardial protection involves limiting the metabolic activity and oxygen consumption of the heart, thus enabling surgery to proceed with minimal blood loss while reducing the level of ischemic injury. It was this concept that allowed for the development of the open-heart surgical technique. We know myocardial ischemia and reperfusion injury are both detrimental, thus developing strategies to mitigate this can help reduce peri-operative morbidity and mortality. In this review, we will mainly be addressing the anesthetic considerations for myocardial protection, along with discussing potential future research which can help expand the field. We searched the PubMed database for relevant studies dating from 2004-2022. In total, 18 studies were deemed suitable for this literature review. Studies have demonstrated cardioprotective effects with use of the volatile agents and propofol, mainly with respect to lower levels of inflammatory markers such as creatine kinase (CK)-MB and troponin I (TnI)/troponin T (TnT). The data is lacking regarding protective effects of dexmedetomidine and lidocaine, hence we cannot recommend either agent at present. Myocardial protection with respect to the anesthetic agents have been extensively studied over the past two decades, some routinely used drugs such as the volatile agents, propofol and opiates have demonstrated a cardioprotective role. The ideal dosing regimen and duration are areas of research that can be studied further. The data for the other anesthetic adjuncts such as lidocaine, dexmedetomidine along with use of regional anesthesia is still equivocal. Alongside advances in anesthesia, we believe surgical research looking into optimal cardioplegia solutions will also help improve myocardial protection in the future.

Peripheral nerve block adjuncts: which medication to choose? A narrative review of the current literature.

Enhancing the effect of peripheral nerve blockade by adding other classes of medications has long history of trial and error. Studies have identified multiple potentially beneficial adjuncts that work to either speed the onset of analgesia or prolong its duration. The benefits of these adjuncts must be weighed against the risks of systemic negative side effects. To date, the most commonly used adjuncts, and ones with the most robust scientific efficacy are, dexamethasone, dexmedetomidine and buprenorphine. This narrative review will discuss several classes of local anesthetic adjuncts and provide evidence for the clinical efficacy and side effect profile of the most commonly studied medications.

Effects of epinephrine, lidocaine, and prilocaine on viability and differentiation capacity of human adipose stem cells

Local anesthetics (LAs) are routinely administered in plastic and reconstructive surgery, e.g., as tumescent anesthesia adjunct in liposuction. Historically, these substances were assumed to act cytotoxically. Thus, the application of LA was avoided when handling adipose stem cells (ASCs). We recently determined that most LAs are not cytotoxic when ASCs are exposed to concentrations used for tumescent liposuction. However, there is limited information when combining LA with epinephrine and about the effects of prilocaine on ASCs. We analyzed the effects of prilocaine or lidocaine in co-exposure with epinephrine on the viability of primary human ASCs, i.e., proliferation, metabolic activity, and cytotoxicity, using crystal violet-staining, PrestoBlue®-, and WST-1 assay. We quantified the impact of short-term incubation of lidocaine and epinephrine on the differentiation of ASCs into the adipogenic, chondrogenic, and osteogenic lineage. After 2h, prilocaine (10mM) significantly reduced metabolic activity and cell numbers, whereas lidocaine only inhibited metabolic activity. After 6h, prilocaine (10mM) and lidocaine significantly decreased metabolic activity as well as cell numbers. The application of high concentrations of epinephrine did not affect cell numbers but diminished metabolic activity. Combining lidocaine with epinephrine had no additional cytotoxic effect. Differentiation into the chondrogenic lineage was significantly inhibited by epinephrine. Deducing from our data, neither lidocaine combined with epinephrine nor prilocaine has a cytotoxic impact on ASCs in vitro at concentrations equivalent to those in tumescent anesthesia and has no long-lasting effect on the differentiation capacity of ASCs into the osteogenic and adipogenic lineage.

Intravenous Dexmedetomidine Use in Total Hip Arthroplasty May Lead to Elevated Rates of Hypotension.

Purpose Enhanced recovery protocols for total hip arthroplasty (THA), using opioid-sparing techniques have become widely used. Reports of novel additions to multimodal pain control regimens have been published, however, a paucity of literature exists on the use of intravenous dexmedetomidine. In this study, we analyzed our experience with intravenous dexmedetomidine and hypothesized that it would reduce postoperative opioid use. Secondary outcomes were also examined, including post-operative hypotension, hemoglobin, length of stay, and discharge disposition. Methods All patients who underwent primary THA at a single tertiary-level center between January 1, 2016, and September 1, 2019, underwent investigation. Diagnosis, surgical approach, anesthetic type, body mass index (BMI), and American Society of Anesthesiologists (ASA) score were recorded. Postoperative clinical measures were analyzed, adjusting for patient and surgical characteristics. Results Of the 599 patients included in the study, 218 patients received intravenous (IV) dexmedetomidine, at a mean dose of 44.9 mg during their operative event. Using a multivariate model, patients in the IV dexmedetomidine group were estimated to have received 24% elevated morphine milligramequivalent at postoperative day zero compared to those in the control group (p = 0.05). In addition, patients in the IV dexmedetomidine group who underwent spinal anesthesia had increased odds of hypotension 3.47 times that of the control [odds ratio (OR) 1.43-8.43, p=0.006]. Conclusions Surprisingly, we found no opioid-sparing effects with the use of IV dexmedetomidine.IV dexmedetomidine may be used cautiously as an anesthesia adjunct with spinal anesthesia in the setting of primary THA, as the experience at our institution illustrated increased odds of postoperative hypotension. Level of evidence This retrospective case-control study has a level of evidence III.

Dexmedetomidine as an anesthetic adjunct is associated with reduced complications and cardiac intensive care unit length of stay after heart valve surgery

BackgroundWe sought to explore the relationship between dexmedetomidine as an anesthetic adjuvant in cardiac surgery and postoperative complications and length of stay (LOS) in the cardiac intensive care unit (CICU).MethodsWe conducted a retrospective study of patients aged 18 years and older who underwent heart valve surgery between October 2020 and June 2022. The primary endpoint of the study was major postoperative complications (cardiac arrest, atrial fibrillation, myocardial injury/infarction, heart failure) and the secondary endpoint was prolonged CICU LOS (defined as LOS > 90th percentile). Multivariate logistic regression analysis was performed for variables that were significant in the univariate analysis.ResultsA total of 856 patients entered our study. The 283 patients who experienced the primary and secondary endpoints were included in the adverse outcomes group, and the remaining 573 were included in the prognostic control group. Multivariate logistic regression analysis revealed that age > 60 years (odds ratio [OR], 1.68; 95% confidence interval [CI], 1.23–2.31; p < 0.01), cardiopulmonary bypass (CPB) > 180 min (OR, 1.62; 95% CI, 1.03–2.55; p = 0.04) and postoperative mechanical ventilation time > 10 h (OR, 1.84; 95% CI, 1.35–2.52; p < 0.01) were independent risk factors for major postoperative complications; Age > 60 years (OR, 3.20; 95% CI, 1.65–6.20; p < 0.01), preoperative NYHA class 4 (OR, 4.03; 95% CI, 1.74–9.33; p < 0.01), diabetes mellitus (OR, 2.57; 95% CI, 1.22–5.41; p = 0.01), Intraoperative red blood cell (RBC) transfusion > 650 ml (OR, 2.04; 95% CI, 1.13–3.66; p = 0.02), Intraoperative bleeding > 1200 ml (OR, 2.69; 95% CI, 1.42–5.12; p < 0.01) were independent risk factors for prolonged CICU length of stay. Intraoperative use of dexmedetomidine as an anesthetic adjunct was a protective factor for major complications (odds ratio, 0.51; 95% confidence interval, 0.35–0.74; p < 0.01) and prolonged CICU stay. (odds ratio, 0.37; 95% confidence interval, 0.19–0.73; p < 0.01).ConclusionsIn patients undergoing heart valve surgery, age, duration of cardiopulmonary bypass, and duration of mechanical ventilation are associated with major postoperative complication. Age, preoperative NYHA classification 4, diabetes mellitus, intraoperative bleeding, and RBC transfusion are associated with increased CICU length of stay. Intraoperative use of dexmedetomidine may improve such clinical outcomes.

Retraction: Dexmedetomidine as anesthetic adjunct for fast tracking and pain control in off-pump coronary artery bypass.

[This retracts the article on p. 6 in vol. 7, PMID: 23717223.].

Comprehensive Analysis of Local Anesthetics Affecting Adipose Stem Cells In Vitro.

Adipose stem cells (ASCs) hold a great regenerative capacity because of their differentiation capability and their secretory activity. Thus, ASC survival is of great significance during perioperative harvesting. Various local anesthetics are commonly applied during fat grafting procedures. These substances are known to impair cellular viability, which would affect graft survival and final outcomes, but the exact extent of their impact on ASC biology is unknown. The authors analyzed the short- and long-term effects of lidocaine, mepivacaine, ropivacaine, and bupivacaine at increasing concentrations (0.1 to 10 mM) on primary human ASC proliferation and metabolic activity. Trilinear differentiation was assessed by oil red O stain (adipogenesis), safranin O (chondrogenesis), and cresolphthalein (osteogenesis) labeling. In supernatants, cytokine [interleukin (IL)-6/IL-8, vascular endothelial growth factor, hepatocyte growth factor] secretion was analyzed by enzyme-linked immunosorbent assay. Bupivacaine at greater than 100 µM demonstrated the strongest anti proliferative effects, whereas lidocaine and ropivacaine did not affect cell numbers. Mepivacaine evoked reciprocal results regarding cell count at greater than 1 mM. Each compound impaired trilinear differentiation. Secretion of hepatocyte growth factor and IL-8 was reduced significantly by local anesthetic exposure; levels were restored after substances were washed out. In vitro data show that lidocaine, mepivacaine, and ropivacaine could be applied at concentrations of 1 to 10 mM without affecting ASC survival. In contrast, bupivacaine at concentrations greater than 100 µM should be administered with great caution. The differentiation of ASCs and the ASC's secretome might already be decreased by each local anesthetic at 1 mM. The authors' experimental data can be of great significance to the clinical practice, as local anesthetics are routinely administered during liposuction as a tumescent anesthesia adjunct. Therapeutic, V.

Comparison of Dexmedetomidine Versus Fentanyl-Based Anesthetic Protocols Under Patient State Index Guidance in Patients Undergoing Elective Neurosurgical Procedures with Intraoperative Neurophysiological Monitoring.

Objectives The study was designed to elucidate the effects of dexmedetomidine as an anesthetic adjunct to propofol in total intravenous anesthesia (TIVA) on anesthetic dose reduction, the quality of intraoperative neurophysiological monitoring (IONM) recordings, analgesic requirements, and recovery parameters in patients undergoing neurosurgical procedures with neurophysiological monitoring. Methods A total of 54 patients for elective neurosurgical procedures with IONM were randomized to group D (dexmedetomidine) and group F (fentanyl). A loading dose of the study drug of 1µg/kg followed by 0.5 µg/kg/h infusion was used in two groups. Propofol-based TIVA with a Schneider target-controlled infusion model was used for induction and maintenance with effect site concentration of 4-5 and 2.5-4 µg/mL, respectively, titrated to a Patient State Index (PSI) of 25-40. Baseline IONM recordings were obtained after induction. The mean propofol consumption, number of patient movements, quality of IONM recordings, number of fentanyl boluses, hemodynamic characteristics, and recovery parameters were recorded. Results The mean propofol consumption was significantly lower in group D when compared to group F (101.4 ± 13.5 µg/kg/min vs 148.0 ± 29.8 µg/kg/min). Baseline IONM recordings were acquired in all patients without any difficulty. The two groups were comparable with respect to the number of additional boluses of fentanyl, patient movements, and recovery characteristics. Conclusion Dexmedetomidine as an adjuvant to propofol in TIVA reduces the requirement of the latter, without affecting the IONM recordings. The addition of dexmedetomidine also ensures stable hemodynamics and decreases the requirement of opioids with similar recovery characteristics.

Magnesium as an adjunct in regional anesthesia: literature review

Neringa Umaraitė1, Audronė Grigaliūnaitė2, Ramūnas Tamošiūnas2 1Lithuanian University of Health Sciences, Academy of Medicine, Faculty of Medicine, Kaunas, Lithuania 2Hospital of Lithuanian University of Health Sciences Kaunas Clinics, Department of Anesthesiology, Kaunas, Lithuania Abstract Background. High-quality regional anesthesia should ensure good operating conditions and effective, long-lasting analgesia after surgery. Ways to prolong analgesia in order to allow early patient mobility and rehabilitation procedures are constantly being sought. Magnesium sulfate (MgSO4) as an adjunct to local anesthetics solutions is an attractive option and is being extensively studied. The aim: to review the scientific literature on usage of MgSO4 as an adjunct in regional anesthesia and to provide clinical conclusions for the application of MgSO4 in this anesthesia. Methods: The search of the scientific literature was performed in PubMed, Google Scholar online databases, using the following keywords and their combinations: ,,magnesium“, ,,peripheral nerve block“, ,,brachial plexus block“, ,,TAP block”, ,,spinal anesthesia“, ,,epidural anesthesia“, ,,neuraxial anesthesia“. 19 publications were included. Descriptive analysis was used to analyze the literature. Results. Regardless of type of regional anesthesia, magnesium combined with a local anesthetic shortens the duration of analgesic onset, prolongs both sensory and motor block durations, alleviates postoperative pain. Furthermore, less analgesics are consumed during surgery and postoperative period. Also, magnesium has advantage over some adjuvants to complement the action of local anesthetics or to avoid certain adverse effects. However, there is no consensus on what concentrations and volumes of MgSO4 solution should be used for different types of regional anesthesia. Conclusions. MgSO4, when used as an adjunct in regional anesthesia, enhances the action of local anesthetics without increasing the frequency of adverse effects. Keywords: magnesium sulfate, regional anesthesia, peripheral blocks, neuraxial anesthesia. Full article https://doi.org/10.53453/ms.2023.2.18

Effect of Dexmedetomidine on Incidence of Emergence Delirium in Adult Nasal Surgery

Background/Purpose/Question. Emergence delirium (ED) is an acute phenomenon that develops in the early phase of recovery from general anesthesia, and characterized by confusion, disorientation, &amp; possible violent behavior, and is a common occurrence particularly with nasal surgery. Dexmedetomidine is a highly selective alpha-2 adrenergic agonist that results in anxiolysis, sedation, analgesia, and sympatholysis without depressing ventilation. This educational scholarly project aimed to review the literature and investigate the effect of intraoperative dexmedetomidine on the incidence of ED in adults recovering from general anesthesia after nasal surgery. Methods/Evidence Search. PubMed and EMBASE were structurally searched from 2011 to 2021. Five randomized controlled studies (RCT) were selected that compared intraoperative dexmedetomidine to a placebo and how the recovery profile was affected in adults after nasal surgery. Key search terms included “anesthesia”, “dexmedetomidine”, “emergence”, “nasal surgery”. Synthesis of Literature/Results/Discussion. There were collectively 392 participants across these five studies, and the incidence of ED in dexmedetomidine groups was significantly lower than control groups (respectively 21% vs. 50%). The mean arterial pressure (MAP) and heart rate (HR) among dexmedetomidine groups exhibited less variability during emergence without hypotension, which indicates a more stable hemodynamic profile. Analgesic and antiemetic requirements in the post-anesthesia care unit (PACU) were decreased in dexmedetomidine groups, however these results were not statistically significant. Conclusion/Recommendations for Practice. Intraoperative dexmedetomidine significantly decreases the incidence of ED. Secondary effects, like hemodynamic stability and analgesia, were observed, but these qualities need to be further studied before they can be generalized. Overall, dexmedetomidine is a safe and effective anesthetic adjunct that facilitates a smoother emergence after nasal surgery without any complications. Keywords: Anesthesia, dexmedetomidine, emergence, nasal surgery