Monitored anesthesia care with dexmedetomidine: a prospective, randomized, double-blind, multicenter trial

Propofol-fentanyl versus propofol-dexmedetomidine in outpatient procedures sedation: a triple-blind, randomized controlled clinical trial

INTRODUCTION

The choice of anesthetic agents plays a crucial role in procedural success. This study aimed to compare the effects of propofol-fentanyl and propofol-dexmedetomidine combinations, focusing on patient and surgeon perspectives in outpatient procedures.

METHODS

A randomized, controlled, triple-blind clinical trial including 128 adult patients undergoing elective outpatient surgical procedures with sedation and local anesthesia. Patients were randomized to receive either propofol-fentanyl (PF, n = 64) or propofol-dexmedetomidine (PDex, n = 64). Primary outcomes were patient satisfaction, assessed using the ISAS-Br score, and the adequacy of sedation, evaluated by the surgeon and measured by a Numerical Rating Scale (NRS) for movement. Respiratory and hemodynamic changes, as well as awakening from anesthesia, adverse events during recovery, and time to hospital discharge were compared.

RESULTS

No difference between patient satisfaction scores (median ISAS-Br [IQR]: PF 2.64 [2.45‒3.00] vs. PDex 3.00 [2.45‒3.00], p = 0.252). The PF group had a significantly lower movement score (median NRS [IQR]: 0.5 [0.00‒2.25] vs. 2.0 [0.00‒5.00], p = 0.006). The incidence of intraoperative events related to respiration and hemodynamics, as postoperative pain and postoperative nausea/vomiting were similar. A higher proportion of patients sedated with PF awoke in the operating room (75% vs. 35.9%, p < 0.001), and 98.4% of the PF group vs. 92.2% of the PDex group were ready for hospital discharge in less than thirty minutes, p = 0.208.

CONCLUSION

Single doses of fentanyl or dexmedetomidine combined with propofol resulted in equivalent patient satisfaction, safety, and discharge times. The propofol-fentanyl combination demonstrated superior sedation adequacy from the surgeon's perspective and facilitated a faster emergence from anesthesia.

Dexmedetomidine as an Adjunctive Sedative in Patients Undergoing Endoscopic Submucosal Dissection: A Systematic Review and Meta-Analysis

Introduction

Endoscopic submucosal dissection (ESD) is a technique for removing dysplastic lesions in the gastrointestinal tract but carries risks like pain and perforation. Dexmedetomidine, an α2-receptor agonist, offers potential benefits as an adjunct sedative during ESD by providing anxiolysis and analgesia. This systematic review and meta-analysis assesses its efficacy and safety.

Methodology

We searched databases including Embase, Medline/PubMed, Scopus, and Web of Science up to April 21, 2024, following PRISMA guidelines. Eligible studies used dexmedetomidine with other sedatives for ESD. We analyzed outcomes such as en-bloc and complete resection rates, sedation duration, and adverse events, using RevMan for meta-analysis with a random-effects model.

Results

The initial search retrieved 216 studies and after screening, eight studies were included in the final analysis. Dexmedetomidine showed no significant difference in en-bloc or complete resection rates compared to controls. Sedation and procedure times were similar between the two groups as well. Dexmedetomidine significantly reduced restlessness (OR 0.15, 95% CI:0.07 to 0.29) and increased bradycardia (OR 7.15, 95% CI 3.17 to 16.11) compared to controls. Upon subgroup analysis, Dexmedetomidine plus Propofol, and Dexmedetomidine plus Midazolam, revealed the same findings regarding restlessness and bradycardia compared to controls which confirmed the adjunctive effects of Dexmedetomidine.

Conclusion

Dexmedetomidine as an adjunctive sedative appears safe and effective in ESD, reducing restlessness without significant adverse events. The risk of bradycardia is increased, which may be reflective of reduced physiological stress. Future studies should explore optimal dosing and compare Dexmedetomidine with other sedatives in diverse populations.

Moderate conscious sedation for transesophageal echocardiography guidance of percutaneous left atrial appendage closure: The MID-DEX protocol

OBJECTIVES

The aim of this study was to assess the feasibility, effectiveness, and safety of a novel moderate conscious sedation protocol of Dexmedetomidine plus Midazolam (MID-DEX MCS) in patients undergoing transcatheter left atrial appendage closure (LAAC).

DESIGN

This is a retrospective and single-arm study.

SETTING

Single-center, hospital.

PARTICIPANTS

All consecutive patients referred for LAAC.

INTERVENTIONS

LAAC procedures were TEE-guided under MCS using Midazolam and Dexmedetomidine.

MEASUREMENTS AND MAIN RESULTS

100 patients underwent LAAC under MID-DEX MCS protocol with an acute procedural success rate of 100 %. Ninety-four patients (94 %) successfully underwent TEE guidance under MCS for LAAC. In 6 patients (6 %), ICE guidance was required. Of these, only 2 cases (2 %) were due to insufficient sedation and psychomotor agitation, while the other 4 patients (4 %) had absolute contraindications to TEE. No MCS-related complications were observed. Conversion from MCS to general anesthesia was not required in any patient.

CONCLUSIONS

LAAC was safe and effective when performed under MCS. The application of the proposed MCS protocol may simplify the LAAC procedure, as well as reduce procedural time and procedural costs, while increasing overall patient and physician satisfaction.

Ultrasound-Guided Rectus Sheath Block With Monitored Anesthesia Care for Necrotic Umbilical Hernia Repair in a Patient With Severe Liver Failure and Refractory Ascites: A Case Report

Patients with severe liver dysfunction present significant perioperative challenges, including the risk of postoperative cognitive dysfunction (POCD) and hepatic encephalopathy (HE), after general anesthesia. While avoiding general anesthesia and deep sedation is crucial for early recovery in this patient population, neuraxial block techniques are often contraindicated due to coagulation disorders. A 73-year-old male patient (190 cm tall, weighing 77 kg) with Child-Pugh C cirrhosis (score 10), coagulopathy (platelets 90,000/μL, prothrombin time (PT) activity 47%), and complex medical history, including treated hepatocellular carcinoma, renal cancer, and bladder cancer, underwent necrotic umbilical hernia repair. The patient, classified as American Society of Anesthesiologists (ASA) physical status IV with a Model for End-Stage Liver Disease (MELD) score of 19, had been hospitalized for two months due to an umbilical hernia infection refractory to antibiotic therapy. After careful preoperative assessment, we selected monitored anesthesia care (MAC) as the preferred anesthetic approach due to the patient's high surgical risk. We performed a bilateral rectus sheath block (RSB) using diluted ropivacaine (0.15%, total 80 mL) with epinephrine (15 μg). Sedation was achieved using dexmedetomidine without a loading dose, supplemented with midazolam and low-dose remifentanil. This approach allowed us to maintain spontaneous breathing while providing adequate analgesia and patient comfort. The surgery was completed successfully with stable hemodynamics and respiratory functions. Throughout the procedure, hemodynamic parameters remained within 20% of baseline values, and bispectral index (BIS) values were maintained between 65 and 80, indicating appropriate sedation depth without excessive anesthetic administration. Ultrasound-guided RSB combined with carefully titrated MAC provides safe and effective anesthesia for umbilical hernia repair in patients with severe liver dysfunction. This approach maintains spontaneous breathing, delivers effective analgesia for somatic and visceral pain, and facilitates clearer differentiation between residual anesthetic effects and worsening HE postoperatively. When coagulopathy precludes neuraxial techniques, this pharmacokinetically informed strategy offers a valuable alternative for high-risk abdominal wall procedures.

Comparison of midazolam and dexmedetomidine combined with thoracic paravertebral block in hemodynamics, inflammation and stress response, and cognitive function in elderly lung cancer patients

OBJECTIVE

This study aimed to compare the clinical outcomes of midazolam and dexmedetomidine combined with ropivacaine-induced thoracic paravertebral nerve block (TPVB) in radical lung cancer surgery.

METHODS

To retrospectively analyze the clinical data of elderly patients who underwent thoracoscopic radical lung cancer surgery from March 2020 to February 2023 in our hospital. All patients underwent a single two-site method of TPVB at the levels of T4 and T7 under ultrasound guidance. The patients were divided into midazolam group (0.25 % ropivacaine + 0.1 mg/kg midazolam) and dexmedetomidine group (0.25 % ropivacaine + 0.8 μg/kg dexmedetomidine) according to the application of sedative drugs, with 78 cases in each group. Ramsay sedation score, mean arterial pressure (MAP), heart rate (HR), electroencephalographic bispectral index (BIS), and blood oxygen saturation (SpO2), as well as the serum levels of C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), epinephrine (E), cortisol (Cor), and norepinephrine (NE) were recorded at 6, 12, 24, 36 and 48 h postoperatively, respectively. The patients' cognitive function was assessed using the Brief Mental State Evaluation Scale (MMSE) at 1 d preoperatively, 1 d postoperatively, and 7 d postoperatively.

RESULTS

The amount of intraoperative sufentanil in the dexmedetomidine group was lower than that in the midazolam group (P < 0.05). The rate of atropine use was higher in the dexmedetomidine group than that in the midazolam group (P < 0.05). There was no significant difference in the occurrence of overall intraoperative adverse reactions (P > 0.05), but the incidence of respiratory depression in the dexmedetomidine group was significantly lower than that in the midazolam group, and the incidence of bradycardia in the dexmedetomidine group was significantly higher than that in the midazolam group (P < 0.05). At T0 ∼ T4, BIS and MAP showed a decreasing trend in both groups. 12, 24, 36 and 48 h postoperatively, the Ramsay sedation score was higher in the dexmedetomidine group than in the midazolam group (P < 0.05). At 36 and 48 h postoperatively, the serum Cor, E, NE, CRP, TNF-α, and IL-6 levels were lower in the dexmedetomidine group than in the midazolam group (P < 0.05). Compared with the preoperative 1d, the MMSE scores were significantly lower in both groups on one day postoperative, while the MMSE scores were significantly higher at postoperative day 7 than on postoperative day 1 (P < 0.05). At postoperative day 1, the MMSE score was significantly higher in the dexmedetomidine group than in the midazolam group (P < 0.05). The difference in the incidence of adverse events within 72 h postoperatively between the two groups was not statistically significant (3.95 % vs. 1.28 %, χ2 = 0.284, P = 0.594).

CONCLUSION

Dexmedetomidine compounded with ropivacaine-induced ultrasound-guided thoracic paravertebral nerve block is superior to midazolam for sedation, anti-inflammation, and anti-stress in elderly lung cancer patients.

Effects of Deep Sedation With Dexmedetomidine Versus Remifentanil on Postoperative Recovery in Soft Tissue Surgery

Background Soft tissue surgery comprises short or medium-duration surgical procedures, with anesthesia consisting of analgesia and sedation. Various quantitative and qualitative recovery scales are used to evaluate the quality of postoperative recovery. The primary objective of this study was to compare the effects of dexmedetomidine versus remifentanil on postoperative recovery using the Quality of Recovery-15 (QoR-15) scale to assess recovery quality in soft tissue surgeries. Methodology This prospective randomized study was conducted at the Clinic of Anesthesia, Reanimation and Intensive Care and University Clinic of Reconstructive and Plastic Surgery, Skopje, Republic of North Macedonia, involving 80 patients. Patients were randomly assigned into two groups, namely, Group 1, sedated with intraoperative dexmedetomidine infusion (Dex, n = 40), and Group 2, sedated with intraoperative remifentanil infusion (Rem, n = 40). Intraoperatively, hemodynamic and respiratory parameters were measured. Preoperatively and postoperatively, levels of leukocytes, blood sugar, and the QoR-15 score were determined. Postoperative mean arterial pressure (MAP), postoperative pain (Visual Analog Scale), and sedation level (Richmond Agitation-Sedation Scale) were compared with the quality of postoperative recovery scores (QoR-15) using Pearson's correlation coefficient. Results The results indicated that dexmedetomidine provided prolonged postoperative sedation and analgesia, which dissipated shortly thereafter, while patients sedated with remifentanil experienced pain immediately upon awakening and required more analgesics. The correlation analysis showed a negative relationship between the degree of postoperative pain and sedation and the quality of recovery. Conclusions Dexmedetomidine demonstrated a superior performance compared to remifentanil. Hence, dexmedetomidine in soft tissue surgery ensures hemodynamic stability, shows protective anti-inflammatory and anti-stress effects, provides good postoperative analgesic effects, reduces recovery time, and protects the body from undesirable postoperative complications.

Dexmedetomidine as an Adjunctive Sedative in Patients Undergoing Endoscopic Submucosal Dissection: A Systematic Review and Meta-Analysis

Introduction

Endoscopic submucosal dissection (ESD) allows for curative en-bloc resection of dysplastic gastrointestinal (GI) tract lesions. However, it is associated with postoperative adverse events (AEs) such as pain, bleeding, and perforation. Dexmedetomidine, an α2-receptor agonist, has emerged as a promising adjunct sedative for ESD under moderate sedation, offering anxiolysis and analgesia. We conducted a systematic review and meta-analysis to evaluate its efficacy and safety for use in ESD.

Methods

A comprehensive systematic search was conducted across multiple databases, including Embase, Medline, Scopus, and Web of Science. Studies that involved ESD utilizing dexmedetomidine as an adjunctive medication in combination with other sedatives, were included. Data extraction and risk of bias assessment were independently performed by two reviewers. Meta-analysis was carried out with RevMan using a random-effects model.

Results

Eight studies were included in the final analysis. Dexmedetomidine showed no significant difference in en-bloc or complete resection rates compared to controls. Sedation and procedure times were similar between the two groups as well. Dexmedetomidine significantly reduced restlessness (OR 0.15, 95% CI:0.07 to 0.29) and increased bradycardia (OR 7.15, 95% CI 3.17 to 16.11) compared to controls. Upon subgroup analysis, Dexmedetomidine plus Propofol, and Dexmedetomidine plus Midazolam, revealed the same findings regarding restlessness and bradycardia compared to controls which confirmed the adjunctive effects of Dexmedetomidine.

Conclusions

Dexmedetomidine as an adjunctive sedative appears safe and effective in ESD, reducing restlessness without significant adverse events. The risk of bradycardia is increased, which may be reflective of reduced physiological stress. Future studies should explore optimal dosing and compare Dexmedetomidine with other sedatives in diverse populations.

Propofol versus Dexmedetomidine for Sedation of Cancer Patients Undergoing Endoscopic Retrograde Cholangiopancreatography: Randomized Single-Blinded Controlled Study

Background

Endoscopic retrograde cholangiopancreatography (ERCP) is a primary diagnostic and therapeutic option for pancreaticobiliary pathologies.

Objectives

This study aimed to investigate the efficacy and safety of dexmedetomidine versus propofol during ERCP in cancer patients.

Methods

This randomized controlled single-blinded trial was conducted with 202 cancer patients aged 21 to 60 years, of both sexes, with a body mass index of 18.5 to 30 kg/m2, and classified as American Society of Anesthesiologists (ASA) class II - III, who were undergoing ERCP. The patients were randomly assigned to two equal groups. The Propofol Group (n = 101) received a loading dose of propofol (1 - 2 mg/kg over 30 seconds) followed by an infusion (0.05 - 0.1 mg/kg/hour). The Dexmedetomidine Group (n = 101) received a loading dose of dexmedetomidine (1 μg/kg over 10 minutes) followed by an infusion (0.2 - 0.7 μg/kg/hour). The maintenance dose was adjusted during the procedure based on vital signs, Bispectral Index (BIS), and oxygen saturation.

Results

The Dexmedetomidine group showed a significantly lower incidence of intra-procedural hypoxemic events (14.9% vs. 26.7%, P = 0.037) and a comparable incidence of hypotension (17.8% vs. 13.9%, P = 0.441). Dexmedetomidine also demonstrated significantly lower intraoperative pain scores according to the Facial Pain Score (P < 0.05), significantly lower postoperative Visual Analog Scale (VAS) scores (P < 0.05), and a lower frequency of postoperative nausea and vomiting (PONV) compared to the Propofol group. Additionally, there was a significantly higher frequency of endoscopist satisfaction in the Dexmedetomidine group compared to the Propofol group (P < 0.05).

Conclusions

Dexmedetomidine can be used as a safe and effective alternative to propofol for deep sedation of cancer patients undergoing ERCP. It is associated with a lower incidence of hypoxemic events, effective intraoperative sedation, quicker recovery, and superior analgesic effects both intraoperatively and postoperatively compared to propofol.

Cross-cultural adaptation and validation of the Iowa Satisfaction with Anesthesia Scale for use in Brazil: a cross-sectional study

BACKGROUND

The Iowa Satisfaction with Anesthesia Scale (ISAS) was developed to assess the satisfaction of patients undergoing sedation with monitored anesthesia care. This study aimed to cross-culturally adapt the ISAS instrument and evaluate the acceptability, validity, and reliability of the proposed Brazilian version (ISAS-Br).

METHODS

The cross-cultural adaptation process involved translation, synthesis, back-translation, expert committee review, pre-testing, and final review of the ISAS-Br. A cross-sectional study was conducted, involving 127 adult individuals undergoing ambulatory surgeries with moderate/deep sedation. The acceptability, reliability, and construct validity of the scale were assessed.

RESULTS

The cross-cultural adaptation process did not require significant changes to the final version of the scale. The ISAS-Br demonstrated excellent acceptability, with a completion rate of 99% and an average completion time of 4.6 minutes. Exploratory factor analysis revealed three factors: emotional well-being, physical comfort, and anxiety relief, with respective composite reliability coefficient values of 0.874, 0.580, and 0.428. The test-retest reliability of the ISAS-Br, measured by the intraclass correlation coefficient, was 0.67 (95% confidence interval [95% CI] 0.42 to 0.83), and the Bland-Altman plot showed satisfactory agreement between the measurements.

CONCLUSION

The proposed Brazilian version of the ISAS underwent successful cross-cultural adaptation according to international standards. It demonstrated good acceptability and reliability, regarding the assessment of temporal stability. However, the ISAS-Br exhibited low internal consistency for some factors, indicating that this instrument lacks sensitivity to assess the satisfaction of deeply sedated patients. Further studies are necessary to explore the hypotheses raised based on the knowledge of its psychometric properties.

Predictors for Dexmedetomidine Requirement for Sedation under Regional Anesthesia

(1) Background: This prospective observational study aimed to investigate the predictors affecting DMT requirements for sedation during regional anesthesia. (2) Method: A total of 108 patients who received regional anesthesia with intravenous DMT administration for orthopedic upper- or lower-extremity surgery were enrolled. Following successful regional anesthesia, DMT was administered at a rate of 4 µg/kg/h until reaching loss of consciousness (LOC). The administered dose of DMT per body weight until LOC (DMTLOC; µg/kg) was evaluated. The infusion was maintained at a rate of 0.2-0.7 µg/kg/h during the surgery. At the end of surgery, the elapsed time to a BIS value of 90 (TBIS90; s) was recorded. Linear regression models were used to identify potential predictors of DMTLOC and TBIS90. (3) Results: One hundred patients were analyzed. There were negative relationships between DMTLOC and age (r = -0.297, p = 0.003) and DMTLOC and body mass index (BMI) (r = -0.425, p < 0.001), respectively. Multiple linear regression models revealed that both increasing age and BMI were significantly related to DMTLOC (r2 = 0.259, p < 0.001), but those variables showed no association with TBIS90. (4) Conclusions: The results of this study suggest that initial loading of DMT should be carefully titrated to minimize risk in elderly and obese surgical populations.

Sedation with propofol/remifentanil versus dexmedetomidine / remifentanil for patients undergoing transcatheter aortic valve implant: A retrospective study between 2012 and 2019

BACKGROUND AND OBJECTIVES

Percutaneous implantation of an aortic valve prosthesis is a therapeutic alternative for patients with severe aortic stenosis. The procedure is traditionally performed under general anaesthesia; however, sedation is now gaining in popularity because it reduces the need for vasoactive drugs and shortens the patient's stay in the critical care unit and on the ward. The aim of this study is to evaluate the clinical efficacy, safety and potential benefits of sedation with dexmedetomidine in patients undergoing percutaneous implantation of an aortic valve prosthesis in terms of haemodynamic and respiratory complications.

MATERIALS AND METHODS

We performed a retrospective study of 222 patients that had undergone percutaneous implantation of an aortic valve prosthesis between 2012 and 2019 under sedation with either dexmedetomidine plus remifentanil (DEX-RMF) or propofol plus remifentanil (PROPO-RMF). We collected data on complications, mainly haemodynamic and respiratory, during and after the procedure.

RESULTS

No significant differences were found between sedation with dexmedetomidine and propofol (in combination with remifentanil) in terms of haemodynamic stability and intraprocedural cerebral blood oxygen. In the DEX-RMF group, however, mean blood pressure, midazolam dose, and duration of anaesthesia were lower compared with the PROPO-RMF group, but the incidence of haemodynamic and respiratory complications did not differ significantly between groups.

CONCLUSIONS

Our results show that sedation, particularly with adjuvant dexmedetomidine, is a valid anaesthetic techniques in percutaneous aortic valve prosthesis implantation.

Regional Anesthesia for Arthroscopic Knee Repair in a Patient With Hypertrophic Obstructive Cardiomyopathy (HOCM) Under Monitored Anesthesia Care With Dexmedetomidine Infusion

Patients with hypertrophic obstructive cardiomyopathy (HOCM) who are scheduled for elective, noncardiac surgery present a distinctive challenge for perioperative healthcare providers. The use of general anesthesia and neuraxial anesthesia carries the risk of unpredictable hemodynamic changes and potential complications. Regional anesthesia (RA) emerges as a prudent and effective option for HOCM patients. RA provides advantages such as minimizing hemodynamic fluctuations, avoiding intubation, reducing pharmacologic side effects, facilitating enhanced recovery after surgery, and contributing to greater patient satisfaction. We share the case of a 15-year-old individual diagnosed with HOCM and exercise intolerance, undergoing arthroscopic repair for right patellar instability. In this instance, the patient received preoperative peripheral nerve blocks for surgical anesthesia and underwent repair utilizing monitored anesthesia care (MAC) with a dexmedetomidine (DEX) infusion.

Monitored Anesthesia Care in Minimally Invasive Spine Surgery-A Retrospective Case Series Study

Background and Objectives: Minimally invasive spine surgery (MISS) under monitored anesthesia care (MAC) has emerged as a treatment modality for spinal radiculopathy. It is essential to secure the airway and guarantee spontaneous respiration without endotracheal intubation during MISS in a prone position. Materials and Methods: To evaluate the feasibility and safety of MAC with dexmedetomidine during MISS, we retrospectively reviewed clinical cases. A retrospective review of medical records was conducted between September 2015 and June 2016. A total of 17 patients undergoing MISS were included. Vital signs were analyzed every 15 min. The depth of sedation was assessed using the bispectral index (BIS) and the frequency of rescue sedatives. Adverse events during anesthesia, including bradycardia, hypotension, respiratory depression, postoperative nausea, and vomiting, were evaluated. Results: All cases were completed without the occurrence of airway-related complications. None of the patients needed conversion to general anesthesia. The median maintenance dosage of dexmedetomidine for adequate sedation was 0.40 (IQR 0.40-0.60) mcg/kg/hr with a median loading dose of 0.70 (IQR 0.67-0.82) mcg/kg. The mean BIS during the main procedure was 76.46 ± 10.75. Rescue sedatives were administered in four cases (23.6%) with a mean of 1.5 mg intravenous midazolam. After dexmedetomidine administration, hypotension and bradycardia developed in six (35.3%) and three (17.6%) of the seventeen patients, respectively. Conclusions: MAC using dexmedetomidine is a feasible anesthetic method for MISS in a prone position. Hypotension and bradycardia should be monitored carefully during dexmedetomidine administration.

Efficacy and safety of sedation with dexmedetomidine in adults undergoing gastrointestinal endoscopic procedures: systematic review and meta-analysis of randomized controlled trials

Background: The sedative role of dexmedetomidine (DEX) in gastrointestinal endoscopic procedures is unclear. We performed this systematic review and meta-analysis to assess the efficacy and safety of sedation with DEX during gastrointestinal endoscopic procedures with a view to providing evidence-based references for clinical decision-making. Methods: The PubMed, Embase, Cochrane Library, Web of Science, and ClinicalTrials.gov databases were searched for randomized controlled trials (RCTs) that compared DEX with different sedatives comparators (such as propofol, midazolam, and ketamine) for sedation in a variety of adult gastrointestinal endoscopic procedures from inception to 1 July 2022. Standardized mean difference (SMD) and weighted mean difference (WMD) with 95% confidence interval (CI) or pooled risk ratios (RR) with 95% CI were used for continuous outcomes or dichotomous outcomes, respectively, and a random-effect model was selected regardless of the significance of the heterogeneity. Results: Forty studies with 2,955 patients were assessed, of which 1,333 patients were in the DEX group and 1,622 patients were in the control (without DEX) group. The results suggested that the primary outcomes of sedation level of DEX are comparable to other sedatives, with similar RSS score and patient satisfaction level, and better in some clinical outcomes, with a reduced risk of body movements or gagging (RR: 0.60; 95% CI: 0.37 to 0.97; p = 0.04; I2 = 68%), and a reduced additional requirement for other sedatives, and increased endoscopist satisfaction level (SMD: 0.41; 95% CI: 0.05 to 0.77; p = 0.03; I2 = 86%). In terms of secondary outcomes of adverse events, DEX may benefit patients in some clinical outcomes, with a reduced risk of hypoxia (RR:0.34; 95% CI: 0.20 to 0.55; p < 0.0001; I2 = 52%) and cough (RR: 0.25; 95% CI: 0.12 to 0.54; p = 0.0004; I2 = 0%), no significant difference in the risk of hypotension, while an increased risk of bradycardia (RR: 3.08; 95% CI: 2.12 to 4.48; p < 0.00001; I2 = 6%). Conclusion: This meta-analysis indicates that DEX is a safe and effective sedative agent for gastrointestinal endoscopy because of its benefits for patients in some clinical outcomes. Remarkably, DEX is comparable to midazolam and propofol in terms of sedation level. In conclusion, DEX provides an additional option in sedation for gastrointestinal endoscopic procedures. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/#searchadvanced.

Hemodynamic instability following intravenous dexmedetomidine infusion for sedation under brachial plexus block: Two case reports

BACKGROUND

Dexmedetomidine (DMED) is frequently used as a sedative in several medical fields. The benefits of DMED include enhanced quality of regional anesthesia, prolonged analgesia, and postoperative opioid-sparing when administered intravenously or perineurally in combination with regional anesthesia. Severe hemodynamic complications, such as profound bradycardia and hypotension, can occur after DMED administration in critically ill patients or overdosage; however, there are few reports of complications with DMED administration following brachial plexus block (BPB).

CASE SUMMARY

We present two cases of hemodynamic instability that occurred following the initial loading of DMED under supraclavicular BPB. A healthy 29-year-old man without any medical history showed profound bradycardia after receiving a loading dose of DMED 0.9 μg/kg for 9 min. DMED administration was promptly stopped, and after receiving a second dose of atropine, the heart rate recovered. A 62-year-old woman with a history of cardiomyopathy became hypotensive abruptly, requiring the administration of inotrope and vasopressors after receiving a reduced loading dose of 0.5 μg/kg for 10 min. Half of the recommended loading dose of DMED was administered due to the underlying heart dysfunction. Decreased blood pressure was maintained despite the intravenous administration of ephedrine. With continuous infusion of dopamine and norepinephrine, the vital signs were maintained within normal ranges. Inotropic and vasopressor support was required for over 6 h after the initial loading dose of DMED.

CONCLUSION

DMED administration following BPB could trigger hemodynamic instability in patients with decreased cardiac function as well as in healthy individuals.

Spinal anesthesia in elective lumbar spinal surgery

Spinal anesthesia (SA) is gaining recognition as a safe and efficacious regional alternative to general anesthesia for elective lumbar surgery. However, unfamiliarity with management issues related to its use has limited the adoption of awake spine surgery, despite its benefits. Few centers in the United States routinely offer SA for elective lumbar surgery, and a comprehensive workflow to standardize SA for lumbar surgery is lacking. In this article, we examine recent literature on the use of SA in lumbar surgery, review the experience of our institution with SA in lumbar surgery, and provide a cohesive outline to streamline the implementation of SA from the perspective of the anesthesiologist. We review the critical features of SA in contemporary lumbar surgery, including selection of patients, methods of SA, intraoperative sedation, and management of several important technical considerations. We aimed to flatten the learning curve to improve the availability and accessibility of the technique for eligible patients.

Comparison of Procedural Sedation With Propofol and Dexmedetomidine During Transcatheter Aortic Valve Replacement Using the Transfemoral Approach

OBJECTIVES

Although procedural sedation is an established method of anesthesia for transcatheter aortic valve replacement (TAVR), reliable evidence to guide the choice of a suitable sedative agent remains scarce. Accordingly, this trial aimed to compare the effect of procedural sedation with dexmedetomidine versus propofol on postoperative neurocognitive and related clinical outcomes in patients undergoing TAVR.

DESIGN

Prospective, randomized, double-blind clinical trial.

SETTING

The study was conducted at the University Medical Centre Ljubljana, Slovenia.

PARTICIPANTS

The study enrolled 78 patients who underwent TAVR under procedural sedation between January 2019 and June 2021. Seventy-one patients randomized into the propofol group (n = 34) and dexmedetomidine group (n = 37) were included in the final analysis.

INTERVENTIONS

Patients in the propofol group received sedation with propofol (continuous intravenous infusion of 0.5-2.5 mg/kg/h), whereas patients in the dexmedetomidine group received sedation with dexmedetomidine (loading dose of 0.5 µg/kg over 10 minutes followed by continuous intravenous infusion of 0.2-1.0 µg/kg/h).

MEASUREMENTS AND MAIN RESULTS

Minimental state examination (MMSE) was performed before and 48 hours after TAVR. There was no statistically significant difference in MMSE scores between groups before TAVR (p = 0.253), but the MMSE after the procedure revealed a significantly lower incidence of delayed neurocognitive recovery (p = 0.005) and thus better cognitive outcomes in the dexmedetomidine group (p = 0.022).

CONCLUSIONS

Compared with propofol, procedural sedation with dexmedetomidine in TAVR was associated with a significantly lower incidence of delayed neurocognitive recovery.

Long-duration upper extremity surgery under brachial plexus block combined with intravenous dexmedetomidine sedation without an anesthesiologist

BACKGROUND

Dexmedetomidine (DEX) provides a unique conscious sedation without respiratory depression. We examined the usefulness of intravenous (IV) DEX sedation combined with brachial plexus block for long-duration upper extremity surgery without an anesthesiologist.

METHODS

We retrospectively reviewed 90 limbs of 86 patients and measured the actual operative time course in detail. The adverse events and the patient-reported outcomes regarding intraoperative pain and depth of sedation were evaluated.

RESULTS

The mean total time of the operation, tourniquet use, and the IV DEX sedation were 150 min, 132 min, and 117 min, respectively. The mean time between discontinuation of IV DEX sedation and completion of the operation was 51 min. The intraoperative adverse events involved bradycardia (21%), hypotension (18%), and oxygen desaturation (3%). The mean visual analog scale scores of pain during brachial plexus block, surgical site pain, tourniquet pain, and depth of the sedation were 23.4 mm, 0.14 mm, 4.2 mm, and 6.6 mm, respectively. Furthermore, 96% patients expressed a preference for receiving anesthesia as brachial plexus block with IV DEX sedation.

CONCLUSIONS

Long-duration upper extremity surgery, even longer than 2 h, was feasible under brachial plexus block combined with IV DEX sedation without an anesthesiologist. For patients with low blood pressure and/or low heart rate, it is recommended to adjust the continuous infusion of IV DEX to less than 0.4 µg/kg/h. To ensure that the patients are able to promptly leave the operating room fully awake, IV DEX infusion should be stopped at least 30 min before finishing the operation.

Effects of dexmedetomidine in non-operating room anesthesia in adults: a systematic review with meta-analysis

BACKGROUND

Dexmedetomidine (DEX) is an α2-adrenergic receptor agonist used for its sedative, analgesic, and anxiolytic effects. Non-Operating Room Anesthesia (NORA) is a modality of anesthesia that can be done under general anesthesia or procedural sedation or/and analgesia. In this particular setting, a level-2 sedation, such as the one provided by DEX, is beneficial. We aimed to study the effects and safety of DEX in the different NORA settings in the adult population.

METHODS

A systematic review with meta-analysis of randomized controlled trials was conducted. Interventions using DEX only or DEX associated with other sedative agents, in adults (18 years old or more), were included. Procedures outside the NORA setting and/or without a control group without DEX were excluded. MEDLINE, ClinicalTrials.gov, Scopus, LILACS, and SciELO were searched. The primary outcome was time until full recovery. Secondary outcomes included hemodynamic and respiratory complications and other adverse events, among others.

RESULTS

A total of 97 studies were included with a total of 6,706 participants. The meta-analysis demonstrated that DEX had a higher time until full recovery (95% CI = [0.34, 3.13] minutes, a higher incidence of hypotension (OR = 1.95 [1.25, 3.05], p = 0.003, I2 = 39%) and bradycardia (OR = 3.60 [2.29, 5.67], p < 0.00001, I2 = 0%), and a lower incidence of desaturation (OR = 0.40 [0.25, 0.66], p = 0.0003, I² = 60%).

CONCLUSION

DEX in NORA procedures in adults was associated with a lower incidence of amnesia and respiratory effects but had a long time to recovery and more hemodynamic complications.

Comparison of Standard-Dose Versus High-Dose Dexmedetomidine in Extracorporeal Membrane Oxygenation

BACKGROUND

Dexmedetomidine is commonly used to achieve light sedation in patients on extracorporeal membrane oxygenation (ECMO) despite minimal evidence. In vivo studies have shown dexmedetomidine sequestration in ECMO circuits, and higher doses may be used to overcome sequestration.

OBJECTIVE

The purpose of this study was to compare safety and efficacy of dexmedetomidine at standard versus high doses in ECMO.

METHODS

A retrospective analysis of adult ECMO patients was performed. Patients were compared as receiving either standard-dose (≤1.5 µg/kg/h) or high-dose (>1.5 µg/kg/h) dexmedetomidine. Safety outcomes included new onset bradycardia or hypotension. Efficacy was compared by the addition of concomitant sedative and analgesic agents.

RESULTS

One hundred five patients were evaluated, with 20% of patients in the high-dose group. Comparing standard and high dosing, no significant differences were seen in primary safety outcomes including bradycardia (49% vs 38%, P = 0.46), hypotension (79% vs 71%, P = 0.56), or addition of vasopressors (75% vs 71%, P = 0.78). Need for concomitant analgesic agents and propofol was similar between groups.

CONCLUSION AND RELEVANCE

This represents the first evaluation of use of high-dose dexmedetomidine in ECMO. Rates of dexmedetomidine higher than 1.5 µg/kg/h were commonly used in patients on ECMO, with similar rates of adverse effects and need for concomitant propofol and analgesic agents. While high-dose dexmedetomidine may be as safe as standard dose, no additional efficacy was found.

Effects of dexmedetomidine on pharyngeal swallowing and esophageal motility-A double-blind randomized cross-over study in healthy volunteers

BACKGROUND

Sedative agents increase the risk of pulmonary aspiration, where an intact swallowing function is an important defense mechanism. Dexmedetomidine is an α2 -adrenoceptor agonist widely used during procedural sedation due to beneficial properties with minimal respiratory effects. The effects of dexmedetomidine on pharyngeal swallowing and esophageal motility are not known in detail.

METHODS

To determine the effects of dexmedetomidine on pharyngeal swallowing and esophageal motility, nineteen volunteers were included in this double-blinded, randomized placebo-controlled cross-over study. Study participants received target-controlled dexmedetomidine and placebo infusions. Recordings of pressure and impedance data were acquired using a manometry and impedance solid-state catheter. Data were analyzed from three bolus swallows series: baseline, during dexmedetomidine/placebo infusion at target plasma concentrations 0.6 ng ml-1 and 1.2 ng ml-1 . Subjective swallowing difficulties were also recorded.

KEY RESULTS

On pharyngeal swallowing, dexmedetomidine affected the upper esophageal sphincter with decreased pre- and post-swallow contractile pressures and an increase in residual pressure during swallow-related relaxation. On esophageal function, dexmedetomidine decreased contractile vigor of the proximal esophagus and increased velocity of the peristaltic contraction wave. Residual pressures during swallow-related esophagogastric junction (EGJ) relaxation decreased, as did basal EGJ resting pressure. The effects on the functional variables were not clearly dose-dependent, but mild subjective swallowing difficulties were more common at the higher dose level.

CONCLUSIONS AND INFERENCES

Dexmedetomidine induces effects on pharyngeal swallowing and esophageal motility, which should be considered in clinical patient management and also when a sedative agent for procedural sedation or for manometric examination is to be chosen.

Comparison of vital sign stability and cost effectiveness between midazolam and dexmedetomidine during third molar extraction under intravenous sedation

Objectives

To compare the vital sign stability and cost of two commonly used sedatives, midazolam (MDZ) and dexmedetomidine (DEX). Patients and.

Methods

This retrospective study targeted patients who underwent mandibular third molar extractions under intravenous sedation using MDZ or DEX. The predictor variable was the type of sedative used. The primary outcome variables were vital signs (heart rate and blood pressure), vital sign outliers, and cost of the sedatives. A vital sign outlier was defined as a 30% or more change in vital signs during sedation; the fewer changes, the higher the vital sign stability. The secondary outcome variables included the observer's assessment of alertness/sedation scale, level of amnesia, patient satisfaction, and bispectral index score. Covariates were sex, age, body mass index, sleeping time, dental anxiety score, and Pederson scale. Descriptive statistics were computed including propensity score matching (PSM). The P-value was set at 0.05.

Results

The study enrolled 185 patients, 103 in the MDZ group and 82 in the DEX group. Based on the data after PSM, the two samples had similar baseline covariates. The sedative effect of both agents was satisfactory. Heart rate outliers were more common with MDZ than with DEX (49.3% vs 22.7%, P=0.001). Heart rate was higher with MDZ (P=0.000). The cost was higher for DEX than for MDZ (29.27±0.00 USD vs 0.37±0.04 USD, P=0.000).

Conclusion

DEX showed more vital sign stability, while MDZ was more economical. These results could be used as a reference to guide clinicians during sedative selection.

Effect of different doses of dexmedetomidine on the median effective concentration of propofol during gastrointestinal endoscopy: a randomized controlled trial

AIMS

Dexmedetomidine could be an ideal adjuvant to propofol during gastrointestinal endoscopy because it provides both analgesia and sedation without respiratory depression. This study investigates the effect of different doses of dexmedetomidine on the median effective concentration of propofol during gastrointestinal endoscopy.

METHODS

Ninety adult patients were randomly assigned to Group Control, Group DEX0.5 (0.5 μg/kg dexmedetomidine) or Group DEX1.0 (1.0 μg/kg dexmedetomidine). Anaesthesia during endoscopy was implemented by plasma target-controlled infusion (TCI) of propofol with different doses of dexmedetomidine. TCI concentration of the first patient for each group was 2.5 μg/mL and the consecutive adjacent concentration gradient was 0.5 μg/mL. Median effective concentration (EC₅₀ ) of propofol by TCI for gastrointestinal endoscopy was determined by using the modified Dixon's up-and-down method. Cardiovascular variables were also measured.

RESULTS

EC₅₀ of propofol by TCI and 95% confidence interval (CI) for gastrointestinal endoscopy were 3.77 (3.48-4.09), 2.51 (2.27-2.78) and 2.10 (1.90-2.33) μg/mL in Group Control, Group DEX0.5 and Group DEX1.0, respectively. The average percent change from heart rate (HR) baseline was 2.8 (8.9), -7.4 (7.7) and -10.5 (8.8) (P < .001), and the average percent change from mean arterial pressure (MAP) baseline was -10.6 [-24.7; 3.5], -9.5 [-29.2; 11.4] and -4.0 [-27.3; 15.5] (P = .034) in Group Control, Group DEX0.5 and Group DEX1.0, respectively.

CONCLUSIONS

Dexmedetomidine reduced the EC₅₀ of propofol by TCI. A 0.5-1 μg/kg dose of dexmedetomidine caused a decrease in HR without bradycardia. The decrease in dosage of propofol with increasing doses of dexmedetomidine caused more stable MAP. Dexmedetomidine is an ideal adjuvant drug to propofol during gastrointestinal endoscopy.

Sedation-analgesia techniques for nonoperating room anesthesia: an update

PURPOSE OF REVIEW

There has been a substantial increase in nonoperating room anesthesia procedures over the years along with an increase in the complexity and severity of cases. These procedures pose unique challenges for anesthesia providers requiring meticulous planning and attention to detail. Advancements in the delivery of sedation and analgesia in this setting will help anesthesia providers navigate these challenges and improve patient safety and outcomes.

RECENT FINDINGS

There has been a renewed interest in the development of newer sedative and analgesic drugs and delivery systems that can safely provide anesthesia care in challenging situations and circumstances.

SUMMARY

Delivery of anesthesia care in nonoperating room locations is associated with significant challenges. The advent of sedative and analgesic drugs that can be safely used in situations where monitoring capabilities are limited in conjunction with delivery systems, that can incorporate unique patient characteristics and ensure the safe delivery of these drugs, has the potential to improve patient safety and outcomes. Further research is needed in these areas to develop newer drugs and delivery systems.

Sedation for magnetic resonance imaging in the prone position - A report of four cases -

Background: Magnetic resonance imaging (MRI) is a useful tool, but it can be difficult to perform in those with claustrophobia as it requires being enclosed in a noisy cylindrical space. Being in the prone position is essential to spread breast tissue. However, sedation in a prone position is challenging because of the possibility of respiratory depression and the difficulty in manipulating the airway. Case: Four patients with claustrophobia were sedated using dexmedetomidine, has minimal effect on respiration. Dexmedetomidine also enables the patient’s cooperation in assuming the prone position while infusing loading time. But dexmedetomidine requires a longer time to reach moderate sedation, an intermittent bolus of midazolam was required for rapid induction of moderate sedation. All exams were conducted successfully without any complications.Conclusions: Administering dexmedetomidine and a midazolam bolus at the appropriate dose and timing will render MRI examinations in the prone position safe and satisfactory, without respiratory complications.

Anesthetic Management of a Patient With Catecholaminergic Polymorphic Ventricular Tachycardia

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare inherited arrhythmogenic disorder induced by adrenergic stress. Electrophysiologically, it is characterized by emotional stress- or exercise-induced bidirectional ventricular tachycardia that may result in cardiac arrest. Minimizing perioperative stress is critical as it can reduce fatal arrhythmias in patients with CPVT. Dexmedetomidine (DEX), a centrally acting sympatholytic anesthetic agent, was used in the successful intravenous (IV) moderate sedation of a 27-year-old female patient with CPVT, a history of cardiac events, and significant dental fear and anxiety scheduled to undergo mandibular left third molar extraction. Oral surgery was successfully performed under DEX-based IV sedation to reduce stress, and no arrhythmias were observed. IV sedation with DEX provided a sympatholytic effect with respiratory and cardiovascular stability in this patient with CPVT who underwent oral surgery.

Comparison of the efficacy and safety of sedation protocols with the use of dexmedetomidine-remifentanil and propofol-remifentanil during percutaneous closure of atrial septal defects: a randomized clinical trial

BACKGROUND

The study was aimed to compare the efficacy and safety of different sedation protocols of dexmedetomidine-remifentanil and propofol-remifentanil for percutaneous closure of atrial septal defects (ASD) under transthoracic echocardiography (TTE) guidance.

MATERIAL AND METHODS

From March 2020 to January 2021, of 114 patients screened, 59 ASD patients scheduled for percutaneous closure under TTE guidance were randomly allocated into the dexmedetomidine-remifentanil (D-R) group (n = 29) and the propofol-remifentanil (P-R) group (n = 30). The incidence of hemodynamic and respiratory adverse events, arterial blood gas analysis, induction and recovery time, pain score, infusion rate of remifentanil, satisfaction of the surgeon and patient, additional sedatives were collected for analysis and comparison.

RESULTS

The induction time was longer in the D-R group than that in the P-R group (17.66 ± 2.65 min vs 11.43 ± 1.48 min; difference, 6.22 min; 95% CI 5.10 to 7.35; P < 0.001). No differences were observed in the 2 groups in terms of the additional sedatives, infusion rate of remifentanil, pain score, recovery time (P > 0.05). There was no difference between the two groups regarding the incidence of cardiovascular adverse events (6 [20.7%] vs 4 [13.3%]; difference, 7.4%; 95% CI - 11.7 to 26.5%; P = 0.506). Respiratory adverse events occurred in 1 patient (3.4%) in the D-R group, and 8 patients (26.7%) in the P-R group (difference, 23.3%; 95% CI 6.2 to 40.5%; P = 0.026). The incidence of hypercapnia was significantly lower in the D-R group (4 [13.8%]) than in the P-R group (13 [43.3%]; difference, 29.5%; 95% CI 7.8 to 51.2%; P = 0.012).

CONCLUSIONS

Except for more rapid the induction time and higher the surgeon satisfaction score in the propofol-remifentanil protocol, the efficacy was similar between two sedation protocols. The hemodynamic stability was comparable, the dexmedetomidine-remifentanil protocol had superior airway security due to fewer hypercapnia and respiratory adverse events.

Comparison of the Efficacy and Safety of Dexmedetomidine Administered in Two Different Modes Under Procedural Sedation and Analgesia in Plastic Surgery

Background

Dexmedetomidine (DEX), a highly selective α2-adrenergic receptor agonist, is now widely used in procedural sedation and analgesia. This study was designed to observe and compare the efficacy and safety of DEX administered in two different modes.

Methods

In total, 100 patients were randomly divided into two groups to receive intravenous DEX 1 µg/kg over 15 min followed by 0.4–0.7 µg/kg/h infusion or DEX 1 µg/kg over 30 min followed by 0.4–0.7 µg/kg/h infusion. Heart rate (HR), mean arterial pressure (MAP), respiratory rate (RR), bispectral index (BIS), Ramsay Sedation Scores (RSS scores), the lowest respiratory rates (LRR), incidences of respiratory adverse events and frequencies of body movements were recorded. Recovery time, recall of intraoperative events, pain scores in PACU and satisfaction of patients and surgeons were assessed.

Results

The BIS at time points from 5 min after anesthesia to the end of surgery in the intervention group were significantly higher (p < 0.05). The RSS scores at time points from 5 min after anesthesia to immediately after induction with DEX were significantly higher in the intervention group (p < 0.05). The HR at time points from the beginning of surgery to 30 min after local anesthesia, the MAP at time points from 30 min after local anesthesia to the end of surgery, and the RR at time points from 5 min after anesthesia to the end of surgery were significantly higher in the intervention group (p < 0.05). Patients in the intervention group had higher LRR, lower incidences of respiratory adverse events, and shorter recovery time (p < 0.05).

Conclusions

Dexmedetomidine infused with a loading dose over 30 min had less impact on patients’ hemodynamics and respiration and could shorten the recovery time after anesthesia in procedural sedation and analgesia.

Clinical Trial Registration

ClinicalTrials.gov, identifier: ChiCTR1900027958.

Local Infiltration Anesthesia for Orbital Exenteration in Patients With Rhino-Orbital Cerebral Mucormycosis: A Case Series

Orbital exenteration is occasionally required for rhino-orbital cerebral mucormycosis. Multiple associated comorbidities can pose a risk for general anesthesia. There is only 1 report of exenteration being performed under trigeminal nerve block. We describe 5 patients who underwent orbital exenteration under local infiltration anesthesia with sedation. Patients and surgeons reported satisfactory conditions, with stable hemodynamics and successful day care management. Orbital exenteration under local infiltration anesthesia can be a safe and effective alternative for patients with rhino-orbital mucormycosis who are at risk with use of general anesthesia.

Determination of the ED95 of intranasal sufentanil combined with intranasal dexmedetomidine for moderate sedation during endoscopic ultrasonography

BACKGROUND

Sedation during endoscopic ultrasonography (EUS) poses many challenges and moderate-to-deep sedation are often required. The conventional method to preform moderate-to-deep sedation is generally intravenous benzodiazepine alone or in combination with opioids. However, this combination has some limitations. Intranasal medication delivery may be an alternative to this sedation regimen.

AIM

To determine, by continual reassessment method (CRM), the minimal effective dose of intranasal sufentanil (SUF) when combined with intranasal dexmedetomidine (DEX) for moderate sedation of EUS in at least 95% of patients (ED₉₅).

METHODS

Thirty patients aged 18-65 and scheduled for EUS were recruited in this study. Subjects received intranasal DEX and SUF for sedation. The dose of DEX (1 μg/kg) was fixed, while the dose of SUF was assigned sequentially to the subjects using CRM to determine ED₉₅. The sedation status was assessed by modified observer’s assessment of alertness/sedation (MOAA/S) score. The adverse events and the satisfaction scores of patients and endoscopists were recorded.

RESULTS

The ED₉₅ was intranasal 0.3 μg/kg SUF when combined with intranasal 1 μg/kg DEX, with an estimated probability of successful moderate sedation for EUS of 94.9% (95% confidence interval: 88.1%-98.9%). When combined with intranasal 1 μg/kg DEX, probabilities of successful moderate sedation at each dose level of intranasal SUF were as follows: 0 μg/kg SUF, 52.8%; 0.1 μg/kg SUF, 75.4%; 0.2 μg/kg SUF, 89.9%; 0.3 μg/kg SUF, 94.9%; 0.4 μg/kg SUF, 98.0%; 0.5 μg/kg SUF, 99.0%.

CONCLUSION

The ED₉₅ needed for moderate sedation for EUS is intranasal 0.3 μg/kg SUF when combined with intranasal 1 μg/kg DEX, based on CRM.

Dexmedetomidine reduces propofol-induced hippocampal neuron injury by modulating the miR-377-5p/Arc pathway

BACKGROUND

Propofol and dexmedetomidine (DEX) are widely used in general anesthesia, and exert toxic and protective effects on hippocampal neurons, respectively. The study sought to investigate the molecular mechanisms of DEX-mediated neuroprotection against propofol-induced hippocampal neuron injury in mouse brains.

METHODS

Hippocampal neurons of mice and HT22 cells were treated with propofol, DEX, and propofol+DEX. In addition, transfection of miR-377-5p mimics or inhibitors was performed in HT22 cells. Neuronal apoptosis was evaluated by a means of terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) or Hochest 33,258 staining; Arc positive expression in hippocampus tissues was detected using a microscope in immunohistochemistry assays; miRNA-377-5p expression was quantified by RT-qPCR; the protein levels of Arc, DNMT3A, and DNMT3B were determined using western blot; Cell Counting Kit-8 (CCK-8) assay was used to detect the viability and apoptotic rate of the neurons; methylation analysis in the miR-377-5p promoter was performed through methylated DNA immunoprecipitation (MeDIP) assay; dual luciferase reporter assay was performed to confirm whether Arc was under targeted regulation of miR-377-5p.

RESULTS

In the current study, both in vitro and in vivo, propofol treatment induced hippocampal neuron apoptosis and suppressed cell viability. DNMT3A and DNMT3B expression levels were decreased following propofol treatment, resulting in lowered methylation in the miR-377-5p promoter region and then enhanced expression of miR-377-5p, leading to a decrease in the expression of downstream Arc. Conversely, the expression levels of DNMT3A and DNMT3B were increased following DEX treatment, thus methylation in miR-377-5p promoter region was improved, and miR-377-5p expression was decreased, leading to an increase in the expression of downstream Arc. Eventually, DEX pretreatment protected hippocampal neurons against propofol-induced neurotoxicity by recovering the expression levels of DNMT3A, miR-377-5p, and Arc to the normal levels. Additionally, DNMT3A knockdown improved miR-377-5p expression but reduced Arc expression, and DNMT3A overexpression exerted the opposite effects. Dual luciferase reporter assay revealed a binding target between miR-377-5p and Arc 3'UTR. The neuroprotective effect of DEX against propofol-induced neuronal apoptosis was diminished after Arc knockdown. Silencing Arc independently triggered the apoptosis of HT22 cells, which was alleviated through transfection of miR-377-5p inhibitors.

CONCLUSIONS

DEX reduced propofol-induced hippocampal neuron injury via the miR-377-5p/Arc signaling pathway.

A Randomized Control Trial of Three Intravenous Dexmedetomidine Doses for Procedural Sedation in Patients Undergoing Minor Gynaecological Surgery

Background: Minor gynaecological procedures are usually done in outpatient settings. Early discharge with minimal haemodynamic compromise is an essential requirement of these procedures. Many sedative drugs are being used for outpatient surgeries. Of the sedative agents available, dexmedetomidine, which has sedative and analgesic sparing effects, has the best safety profile in the cardiorespiratory system. Therefore, we evaluated the optimum dexmedetomidine dose for providing better procedural sedation.

Methodology: This randomized, double-blinded study included 120 ASA grade I and II patients aged 18-45 years who were undergoing short gynaecological procedures in a tertiary care hospital. Patients were randomly allocated into three groups of 40 each. After a loading dose of 1 µg/kg over 10 min, group A received dexmedetomidine infusion at a rate of 0.2 µg/kg/hr, group B at a rate of 0.4 µg/kg/hr, and group C at a rate of 0.6 µg/kg/hr. Perioperative hemodynamic changes, intraoperative adjuvant drug requirements, and postoperative recovery were also compared in the three different dexmedetomidine groups.

Results: Heart rate, blood pressure, oxygen saturation, and respiratory rate remained within the normal physiological range in all three groups at most perioperative time points. The time to achieve the Modified Aldrete Score and the post-anesthetic discharge scoring system was maximum in group C and minimum in group A. Ketamine had to be supplemented in almost half of the patients in group A and less than a quarter of the patients in group B. In group C, surgery was completed without any drug supplementation. Two patients in group B and four patients in group C had an episode of bradycardia. Oxygen saturation decreased in one patient in group C, necessitating oxygen supplementation.

Conclusions: Dexmedetomidine, at a dose of 0.4 µg/kg/hr with ketamine supplementation, provides the most appropriate procedural sedation and analgesia (PSA) without any significant hemodynamic compromise.

Opioid-free TIVA Improves Post- operative Quality of Recovery (QOR) in Patients Undergoing Oocyte Retrieval

BACKGROUND

Oocyte retrieval is a part of in vitro fertilisation (IVF) procedures performed on an ambulatory basis. Total intravenous anaesthesia (TIVA) with opioid is shown to improve quality of recovery (QOR) after ambulatory surgery. Opioid-free anaesthesia (OF) is gaining popularity in recent times as it is associated with lesser post-operative side effects related to opioids. Quality of recovery is considered as one of the principal end points in ambulatory surgery.

AIM

To compare quality of recovery using QOR-15 questionnaire between opioid-free TIVA and opioid-based TIVA at 24 h after oocyte retrieval.

SETTINGS AND DESIGN

A prospective randomised control study.

PATIENTS AND METHODS

Sixty six patients undergoing oocyte retrieval were prospectively selected. They were randomised into two equal group. OF TIVA group with dexmedetomidine (D) and propofol or opioid-based TIVA with fentanyl (F) and propofol. The primary outcome measured was quality of recovery using QOR-15 at 24 h after oocyte retrieval. Secondary outcomes measured were incidence of bradycardia, post-operative nausea and vomiting, usage of rescue analgesia and total consumption of propofol.

RESULTS

A statistically significant difference in total QOR-15 was observed between two groups (p value = 0.021) at 24 h post-operatively. Usage of rescue analgesia and incidence of post-operative nausea and vomiting was less in opioid-free TIVA.

CONCLUSION

Opioid-free TIVA improves post-operative QOR in patients undergoing oocyte retrieval.

Review of the Physiology and Anesthetic Considerations for Pleuroscopy/Medical Thoracoscopy

Pleuroscopy or medical thoracoscopy is the second most common utilized procedure after bronchoscopy in the promising field of interventional pulmonology. Its main application is for the diagnosis and management of benign or malignant pleural effusions. Entry into the hemithorax is associated with pain and patient discomfort, whereas concurrently, notable pathophysiologic alterations occur. Therefore, frequently procedural sedation and analgesia is needed, not only to alleviate the patient's emotional stress and discomfort by mitigating the anxiety and minimizing the pain but also for yielding better procedural conditions for the operator. The scope of this review is to present the physiologic derangements occurring in pleuroscopy and compare the various anesthetic techniques and sedative agents that are currently being used in this context.

Monitored Anesthesia Care with Dexmedetomidine Supplemented by Midazolam/Fentanyl versus Midazolam/Fentanyl Alone in Patients Undergoing Pleuroscopy: Effect on Oxygenation and Respiratory Function

Although pleuroscopy is considered a safe and well tolerated procedure with a low complication rate, it requires the administration of procedural sedation and analgesia. The purpose of this study was to assess the effects of dexmedetomidine administration on oxygenation and respiratory function in patients undergoing diagnostic or therapeutic pleuroscopy. Through a prospective, single center, cohort study, we studied 55 patients receiving either a dexmedetomidine intravenous infusion supplemented by midazolam/fentanyl (Group DEX + MZ/F) or a conventional sedation protocol with midazolam/fentanyl (Group MZ/F). Our primary outcome was the changes in lung gas exchange (PaO₂/FiO₂ ratio) obtained at baseline and at predetermined end points, while changes in respiratory mechanics (FEV1, FVC and the ratio FEV1/FVC) and PaCO₂ levels, drug consumption, time to recover from sedation and adverse events were our secondary endpoints (NCT03597828). We found a lower postoperative decrease in FEV1 volumes in Group DEX + MZ/F compared to Group MZ/F (p = 0.039), while FVC, FEV1/FVC and gas exchange values did not differ between groups. We also found a significant reduction in midazolam (p < 0.001) and fentanyl consumption (p < 0.001), along with a more rapid recovery of alertness postprocedure in Group DEX + MZ/F compared to Group MZ/F (p = 0.003), while pain scores during the postoperative period, favored the Group DEX + MZ/F (p = 0.020). In conclusion, the use of intravenous dexmedetomidine during pleuroscopy is associated with a smaller decrease in FEV1, reduction of the consumption of supplementary sedatives and analgesics and quicker awakening of patients postoperatively, when compared to midazolam/fentanyl. Therefore, dexmedetomidine administration may provide clinically significant benefits in terms of lung mechanics and faster recovery of patients undergoing pleuroscopy.

Is Spinal Dexmedetomidine Aggravating Hypotension after Tourniquet Deflation?

Background and Aims:

The addition of dexmedetomidine to spinal anesthesia decreases the incidence of tourniquet pain but may aggravate hypotension after tourniquet deflation.

Methods:

Fifty patients were included in this prospective, double-blinded, randomized study, randomly divided into two equal groups of 25 patients each. Spinal anesthesia was performed using 2.5 mL of 0.5% hyperbaric bupivacaine plus 0.5 mL of normal saline in control group (Group C) or 2.5 mL of 0.5% hyperbaric bupivacaine plus 0.5 mL (5 μg) of dexmedetomidine in (Group D). Tourniquet pain was treated by 50 mg of meperidine and repeated in a dose of 20 mg, and the total meperidine consumption was calculated. After tourniquet deflation, heart rate and mean blood pressure were measured for 15 min in the operating room and at these times: before induction of anesthesia (baseline), after inflating tourniquet (inflation), 1 min before deflating tourniquet (predeflation), after tourniquet deflation (10 min postdeflation), and maximum blood pressure and heart rate changes. Duration of time that started before the minimum blood pressure and maximum heart rate was changed until recovery was recorded.

Results:

Pain after torniquet inflation was significantly higher in the Group C compared to the Group D. The maximal change of blood pressure was lower in the dexmedetomidine than in the control group. The mean time between the maximal change in blood pressure reached and started to recover was 135 ± 14 s in the dexmedetomidine group and 80 ± 31 s in the control group (P < 0.01) and maximal heart rate change was lower in dexmedetomidine group than the control group. The time between the maximal heart rate changes until recovery was 113.2 ± 19 s in the dexmedetomidine group and 53.2 ± 11 s in the control group P < 0.01.

Conclusion:

Adding dexmedetomidine to spinal anesthesia decreases the incidence of tourniquet pain but aggravates the hemodynamic effect of tourniquet deflation.

Comparison of Two Different Sedation Protocols during Transvaginal Oocyte Retrieval: Effects on Propofol Consumption and IVF Outcome: A Prospective Cohort Study

(1) Background: There has been various reports on the potential impact of anesthetic agents used during oocyte retrieval (OR) on the impairment of the capacity of the oocyte for fertilization and subsequent embryo quality; results have been conflicting; (2) Methods: The effects of two different sedation protocols during OR in two groups of patients undergoing In Vitro Fertilization/Intra-Cytoplasmic Sperm Injection IVF/ICSI, were compared on propofol consumption and on in vitro fertilization (IVF)/ICSI success. The study group received dexmedetomidine and fentanyl, while the control remifentanil and midazolam. In a prospective cohort study, we encompassed 72 cycles/patients. The administered dose of propofol per patient and fertilization rates were the primary outcomes, while anesthesiological parameters and IVF/ICSI outcomes were the secondary endpoints; (3) Results: We found a significant increase in propofol consumption in the study compared to the control group (77.0 ± 10.6 mg vs. 12.1 ± 6.1; p < 0.001), but fertilization rates were similar (p = 0.469). From the secondary anesthesiological outcomes, the post anesthesia discharge scores were better in the control group (15.0 (13.5 min) vs. 5.0 (10.0 min), p = 0.028). From the IVF/ICSI secondary outcome parameters, we found a higher quality of embryos on day three in the study compared to the control group (p = 0.040). The comparison of the other secondary outcomes yielded non-significant differences; (4) Conclusions: The use of dexmedetomidine, as an alternative agent during OR, was associated with higher propofol consumption as a rescue dose compared to remifentanil but was linked with similar fertilization rates and higher quality of embryos produced.

Dexmedetomidine reduces postoperative cognitive and behavioral dysfunction in adults submitted to general anesthesia for non-cardiac surgery: meta-analysis of randomized clinical trials

Introduction and objectives

Dexmedetomidine (DEX) has been associated with a decrease in postoperative cognitive and behavioral dysfunction in patients submitted to general anesthesia, whether inhalation or total intravenous anesthesia. Consequently, the DEX effects on postoperative agitation and delirium in patients submitted to general anesthesia for non-cardiac surgery have been investigated.

Method

A systematic review and meta-analysis of randomized and double-blind clinical trials (RCTs) was undertaken assessing adults submitted to elective procedures under general anesthesia receiving DEX or placebo. The search included articles published in English in the Pubmed and Web of Science databases using keywords such as dexmedetomidine, delirium, and agitation. Duplicate publications, studies involving cardiac surgery or using active control (other than saline solution) were included. A random effects model was adopted using the DerSimonian-Laird method and estimate of Odds Ratio (OR) for dichotomous variables, and weighted mean difference for continuous variables, with their respective 95% Confidence Intervals (95% CI).

Results

Of the 484 articles identified, 15 were selected comprising 2,183 patients (1,079 and 1,104 patients in the DEX and control group, respectively). The administration of DEX was considered a protective factor for postoperative cognitive and behavioral dysfunction (OR = 0.36; 95% CI 0.23–0.57 and p < 0.001), regardless of the anesthesia technique used.

Conclusion

Dexmedetomidine administration reduced by at least 43% the likelihood of postoperative cognitive and behavioral dysfunction in adult patients submitted to general anesthesia for non-cardiac surgery.

Dexmedetomidine-remifentanil vs propofol-remifentanil for monitored anesthesia care during hysteroscopy: Randomized, single-blind, controlled trial

BACKGROUND

Although dexmedetomidine has been used as either the anesthetic agent for light sedation or as an adjunct to other sedatives, no study has investigated the usefulness of dexmedetomidine as the main sedative agent for invasive and painful procedures. The purpose of this study was to compare the safety of dexmedetomidine-remifentanil and propofol-remifentanil during monitored anesthesia care (MAC) for hysteroscopy.

METHODS

Female patients undergoing hysteroscopy were randomly assigned to either the dexmedetomidine (group D) or the propofol group (group P). The study drug (0.6 ml/kg; dexmedetomidine 2 μg/ml or propofol 4 mg/ml) was loaded for 10 minutes followed by 0.1 to 0.5 ml/kg/hour to maintain a bispectral index of 60 to 80 during the procedure. In both groups, remifentanil was infused using a target-controlled-infusion system with a target concentration of 2 ng/ml and titrated during the procedure. The incidence rates of intraoperative respiratory depression in both groups were compared. Postoperative pain and patients satisfaction were also compared.

RESULTS

A total of 69 female patients were included in this study. Dexmedetomidine significantly decrease the incidence of respiratory depression compared with propofol (15/34 [44.1%] vs 5/35 [14.3%], P = .006, group P and D, respectively). Postoperative pain and patients satisfaction score did not differ between the groups.

CONCLUSION

The combination of dexmedetomidine-remifentanil can reduce the incidence of respiratory depression without increasing hemodynamic complications compared with propofol-remifentanil for MAC during hysteroscopy.

Clinical and economic impact of the use of dexmedetomidine for sedation in the intensive care unit compared to propofol

Background Despite the advantages of dexmedetomidine (DEX) over propofol (PRO) including minimal respiratory depression and the potential for preventing and/or treating intensive care unit (ICU) delirium, PRO has been the preferred agent due to its lower cost. However, the acquisition cost of DEX has considerably decreased as a generic version of DEX has recently become available. Objective To evaluate clinical and economic outcomes of DEX-based sedation compared to PRO in the ICU. Setting A retrospective cohort study of 86 ICU patients who received either DEX or PRO for a period ≥ 12 h. Method Patients were matched by age, sex, and Sequential Organ Failure Assessment scores in a 1:1 ratio. Main outcome measure Clinical outcomes included the duration of mechanical ventilation (MV), ICU and hospital length of stay (LOS), and requirements of concomitant sedatives and opioids. Economic outcomes included the ICU and hospital costs as well as the cost of sedatives or combined sedatives and opioids per patient. Results There were no significant differences in ICU and hospital LOS and time on MV in both groups (median ICU LOS 7 [DEX] vs. 9 [PRO] days, p = 0.07; median hospital LOS 12 [DEX] vs. 14 [PRO] days, p = 0.261; median time of MV 144 [DEX] vs. 158 [PRO] hours, p = 0.176). DEX-based sedation compared to PRO was associated with similar ICU and hospital costs (US$ 67,561 vs. 78,429, p = 0.39; US$ 71,923 vs. 71,084, p = 0.1). Conclusion The clinical outcomes and economic impact associated with DEX- and PRO-based sedation were similar.

Dexmedetomidine Is an Equal Cost Alternative to Propofol in Transcatheter Aortic Valve Replacement, With Equivalent In-Hospital and 30-Day Outcomes

OBJECTIVE

Transcatheter aortic valve replacement (TAVR) with monitored anesthesia care (MAC) is well-tolerated and is growing in popularity. Differences in outcomes based on anesthetic agent choice with MAC has received less attention. The authors sought to determine whether differences in outcomes and cost exist based on whether patients receive dexmedetomidine or propofol when undergoing TAVR with MAC.

DESIGN

Retrospective cohort study.

SETTING

The Penn State Milton S. Hershey Medical Center, Hershey, Pennsylvania.

PARTICIPANTS

The study comprised 161 patients who underwent TAVR with MAC between May 2014 and March 2019.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A propofol-only (n = 58) group and dexmedetomidine-only (n = 103) group were identified. No differences in in-hospital mortality or complication rate were identified when evaluating for stroke, transfusion, new arrhythmia, cardiac arrest, or bleeding and vascular complications (p > 0.05, all). Thirty-day outcomes were also equivalent, with no differences in mortality, stroke, vascular complication, new arrhythmia, or myocardial infarction (p > 0.05, all). The average amount of epinephrine, norepinephrine, or phenylephrine used intraoperatively was not significantly different. Overall median hospitalization costs were equivalent ($57,554.31 with dexmedetomidine v $58,538.08 with propofol, p = 0.97).

CONCLUSIONS

There were no significant differences in in-hospital outcomes, 30-day outcomes, or total cost of the patient's hospitalization, based on the use of dexmedetomidine versus propofol in patients undergoing TAVR.

Dexmedetomidine Provides Fewer Respiratory Events Compared With Propofol and Fentanyl During Third Molar Surgery: A Randomized Clinical Trial

PURPOSE

Propofol and fentanyl can cause airway obstruction and respiratory depression when used together for intravenous sedation. This study investigated whether dexmedetomidine and midazolam would decrease respiratory events requiring intervention during deep sedation compared with propofol, fentanyl, and midazolam.

PATIENTS AND METHODS

A prospective, randomized, double-blinded, controlled trial was designed to assess 2 intravenous treatment groups during third molar surgery. Patients were randomized into 2 groups. The control group (group P) received 0.8 μg/kg of fentanyl followed by propofol infusion at 125 μg/kg per minute over a 10-minute period with intraoperative boluses of 0.1 μg/kg. The study group (group D) received dexmedetomidine bolus infusion of 1 μg/kg over a 10-minute period followed by maintenance infusion at 0.5 μg/kg per hour. Both groups were given 0.03 mg/kg of midazolam before infusion. Scorers, masked to group, viewed the procedure remotely and evaluated the primary outcome variable of respiratory events requiring intervention. Secondary outcome variables evaluated by the scorers included the Behavioral Pain Scale for non-intubated patients at initial injection, cooperation score at 5 and 15 minutes, and time to ambulation and discharge. Patient satisfaction and hemodynamic stability were measured. The difference between groups regarding the occurrence of respiratory events was tested using the Fisher exact test, and mixed-effects models were used to compare repeated vital signs.

RESULTS

The sample was composed of 141 patients randomly assigned to either group P (n = 67) or group D (n = 74). No statistically significant differences in the distribution of study variables were found between groups at baseline. A statistically significant difference in respiratory events requiring deliberate intervention existed between group P (25.4%) and group D (2.7%) (P < .0001). No statistically significant difference was found between groups for Behavioral Pain Scale score, cooperation score, time to ambulation or discharge, and patient satisfaction.

CONCLUSIONS

Using dexmedetomidine and midazolam for outpatient surgery resulted in fewer respiratory events requiring deliberate intervention compared with propofol, fentanyl, and midazolam. Ambulation and discharge times were not prolonged using dexmedetomidine.

Effects of dexmedetomidine on cognitive function in elderly patients after laparoscopic cholecystectomy: A protocol for systematic review and meta-analysis

BACKGROUND

Although many studies have reported the effects of dexmedetomidine on cognitive function (CF) in elderly patients after laparoscopic cholecystectomy (LCT), to this date, its effects are still not well understood. The aim of this study is to produce a qualitative synthesis of assessing the effects of dexmedetomidine on CF in elderly patients after LCT.

METHODS

We will conduct a comprehensive search in Cochrane Library, MEDLINE, EMBASE, CINAHL, PsycINFO, Scopus, VIP Database, WANGFANG Database, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure from the commencement to March 31, 2020 without restrictions of language and publication status. In addition, we will also search grey literature, including conference abstracts, dissertations, reference lists of included studies and relevant reviews. All potential studies will be identified independently by 2 authors to determine their inclusion against previously defined eligibility criteria. The quality of selected papers will be assessed using Cochrane risk of bias tool. All statistical analysis will be performed using RevMan 5.3 software.

RESULTS

This study will provide a synthesis of the current available data on assessing the effects of dexmedetomidine on CF in elderly patients after LCT.

CONCLUSIONS

Its findings will provide qualitative evidence to better understand the effects of dexmedetomidine on CF in elderly patients after LCT.INPLASY Registration Number: INPLASY202040030.

A contemporary approach to sedation during regional anaesthesia in gynaecology

Safe and adequate sedation during regional anesthesia is one of the issues at the current time. According to the basic principles of modern anesthesiology, safe and effective sedation should protect the patient’s psycho-emotional sphere, provide absence of awareness, pain and fear during surgery as well as nausea and vomiting in the postoperative period. At the same time, it should neither cause respiratory depression and haemodynamics changes, nor be accompanied by a slow recovery of psychomotor function.After studying modern literature and analyzing our own observations, we reached the point that sedation with dexmedetomidine rather than propofol is more preferred during regional anaesthesia. Sedation with dexmedetomidine decreases frequency of cognitive impairment in the early postoperative period, intensity of the pain syndrome, and has beneficial effect on recovery and activation after surgery. Additionally, it is associated with lower risk of hypoxemia and arterial hypotension during surgery.

A Historical Review of Indian Perspectives on Techniques of Tympanoplasty

Reconstructive surgery of the conductive hearing mechanism is collectively called as tympanoplasty, which has gradually evolved over time with the contributions from all over the word. The aim of the present historical review is to summarize the Indian contributions in the development of the technique of tympanoplasty. The literature review was conducted using only the “Medline” search using keywords “tympanoplasty” and “ossiculoplasty” in “India” on 15^th June 2016. A total of 195 articles and abstracts were found dated from the year 1998 onwards. Articles describing work on technique were included, and those describing only experimentation with graft material were excluded. All articles were fully read and analysed. It was found that there had been experiments regarding the choice of anaesthesia and the use of combinations of different chemical agents for this purpose. There were suggestions in favour of monitored anaesthesia care for the surgery in select patients. Surgeons expressed their perspectives on the time and conditions for the surgery, laterality of surgery, different types of incisions, use of endoscopes, graft placement techniques, ossicular replacements with autologous or allogenic grafts, and the timing of prophylactic antibiotic therapy given after or during the surgery. The range of work is wide and covers most of the aspects of surgery; however, the incorporation of a uniform methodology and standards reporting results were lacking in the articles reviewed.

Intraoperative Dexmedetomidine Versus Midazolam in Patients Undergoing Peripheral Surgery With Mild Traumatic Brain Injuries: A Retrospective Cohort Analysis

Background:

The intra- and postoperative effects of dexmedetomidine are not completely consistent and midazolam/fentanyl is most widely used in peripheral surgeries. The objectives of the study were to evaluate the sedative, analgesic, hemodynamic, anti-inflammatory, and antioxidant effects of dexmedetomidine against midazolam in patients undergoing peripheral surgeries with mild traumatic brain injuries.

Methods:

Medical records of patients who underwent peripheral surgeries with mild traumatic brain injury were included in the analysis. Patients received intraoperative midazolam (MDZ cohort, n = 225) or dexmedetomidine (DEX cohort, n = 231). Pre-, intra-, and postoperative characteristics of patients were collected and analyzed.

Results:

After administration of anesthesia, up to 40 minutes, patients of the MDZ group had lower modified observer’s assessment of alertness/sedation score than those of the DEX group (P = .041), but after 40 minutes, patients of the MDZ group had a higher score than those of the DEX group throughout surgeries (P = 0.048). The DEX group has less requirements of postoperative morphine/equivalent doses than the MDZ group (4 ± 1 vs 5 ± 1, P < .0001, q = 18.451).

Conclusions:

Intraoperative DEX offers better sedation, postoperative analgesia, and clinical recovery for peripheral surgeries and suppresses inflammatory response.

Level of Evidence:

III.

Dexmedetomidine elevates the lethal dose threshold of bupivacaine in rats: A dosing study

Dexmedetomidine (DMED), an alpha-2 adrenoreceptor agonist, has been widely used in regional anesthesia procedures. However, the effect of DMED on local anesthetic cardiotoxicity has not been well delineated. This study consisted of two experiments. In experiment A, 42 Sprague–Dawley (SD) rats were randomly divided into 6 groups ( n = 7), each group was pretreated with DMED 0 μg kg−1 (D0 group), 1 μg kg−1 (D1 group), 3 μg kg−1 (D3 group), 6 μg kg−1 (D6 group), 12 μg kg−1 (D12 group), and 24 μg kg−1 (D24 group), administered through the right femoral vein. In experiment B, 20 SD rats were randomly divided into 4 groups ( n = 5), such as control group, DMED group, yohimbine (YOH) group, and DMED + YOH group. Each subgroup in experiment B was also pretreated similarly as in experiment A. After pretreatment of rats as described above (in experiments A and B), bupivacaine 2.5 mg kg−1 min−1 was infused to induce cardiac arrest. In experiment A, the lethal dose threshold of bupivacaine and plasma bupivacaine concentration in D3 and D6 group were higher than the other groups. In experiment B, there was no interaction between DMED and YOH in lethal dose threshold, arrhythmia time, plasma concentration of bupivacaine, and myocardial content of bupivacaine. DMED doses of 3–6 μg kg−1 elevated the lethal dose threshold of bupivacaine without involvement of the alpha-2 adrenoceptors.