The Safety and Efficacy of Intranasal Dexmedetomidine During Electrochemotherapy for Facial Vascular Malformation: A Double-Blind, Randomized Clinical Trial

Intranasal Atomized Dexmedetomidine in Combination With Intranasal Atomized Butorphanol for Dressing Change Sedation and Analgesia in Adult Burn Patients: A Randomized Clinical Trial

We aimed to evaluate the efficacy of the intranasal atomized dexmedetomidine (IAD) + intranasal atomized butorphanol (IAB) combination therapy on adult patients with burns undergoing dressing changes. Herein, 46 adult patients with burns were enrolled and randomly divided into 2 groups: dexmedetomidine-butorphanol (DB) and saline-butorphanol, treated with atomized dexmedetomidine + butorphanol and saline + butorphanol, respectively. The primary outcomes were the Ramsay Sedation Scale (RSS) and the Visual Analog Scale (VAS) scores. The secondary outcomes were mean blood pressure (MBP), heart rate, respiratory rate (RR), peripheral blood oxygen saturation (SpO2), total butorphanol consumption, and adverse effects. The 2 groups were comparable in age, sex, weight, and total burn surface area. During dressing changes, the DB group exhibited significantly lower RSS levels (P < .05). Besides, the 2 groups showed no significant differences in VAS scores across all measurement time points. Notably, the DB group exhibited decreased MBP at the beginning of the operation (P < .0001), 10 min after (P < .0001), and 20 min after (P = .0205). Heart rate decreased significantly at the beginning (P = .0005) and 10 min after (P = .0088) in the DB group. Furthermore, the 2 groups showed no significant differences in RR and SpO2 levels. In addition, the rescue butorphanol dose was lower in the DB group (P < .001). Finally, dizziness and nausea incidences were significantly lower in the DB group (P < .05). In conclusion, besides its hemodynamic adverse reactions, the IAD + IAB combination therapy exerted a better sedation effect in adult patients with burns than IAB treatment alone.

Comparative evaluation of intravenous versus intranasal dexmedetomidine on emergence delirium and hemodynamics in pediatric patients undergoing adenotonsillectomy: a randomized controlled trial

Background

Dexmedetomidine effectively prevents emergence delirium in children. However, intravenous dexmedetomidine is frequently associated with hemodynamic instability and delayed recovery. Intranasal dexmedetomidine has been proposed as a method of reducing these side effects. This study aimed to evaluate the effects of intranasal versus intravenous dexmedetomidine on emergence recovery and hemodynamics in children undergoing adenotonsillectomy.

Methods

A total of 139 children, aged 3-10 years, who were scheduled for elective adenotonsillectomy were randomly assigned to receive intravenous dexmedetomidine (IV DEX group) or intranasal dexmedetomidine (IN DEX group), or saline (control group) after anesthesia induction. The primary outcome was the highest score on the pediatric anesthesia emergence delirium (PAED) score during the first 30 min after awakening. Secondary outcomes included the perioperative blood pressure and heart rate, time to awakening, postoperative pain score, and length of post-anesthesia care unit (PACU) stay.

Results

The highest PAED and pain scores were significantly lower in the IV and IN DEX groups than those in the control group during the first 30 min after awakening. However, no significant differences were observed between the IV and IN DEX groups. Notably, patients in the IN DEX group exhibited a significantly lower PAED score at 2 h and lower pain scores at 2, 4, and 6 h postoperatively than those in the IV DEX group. Patients in the IV DEX group exhibited a significantly longer awakening time and length of PACU stay than those in the IN DEX and control groups. In the IV DEX group, the heart rate was significantly lower perioperatively than at baseline, while this effect was not observed in the IN DEX group.

Conclusion

Both intravenous and intranasal administration of dexmedetomidine after induction of anesthesia effectively improved emergence delirium and pain intensity in children undergoing adenotonsillectomy. Intranasal administration of dexmedetomidine provided more stable hemodynamics and more prolonged analgesia and sedation than intravenous infusion of dexmedetomidine.

Clinical Trial Registration

https://www.chictr.org.cn/showproj.html?proj=180658.

Intranasal dexmedetomidine improves postoperative sleep quality in older patients with chronic insomnia: a randomized double-blind controlled trial

Objective: This study was determined to investigate the impact of intranasal dexmedetomidine (DEX) on postoperative sleep quality in older patients (age over 65) with chronic insomnia during their hospitalization after surgery. Design: A randomized double-blind controlled trial was conducted to compare the effects of intranasal dexmedetomidine spray with a placebo group. Setting and Participants: The study was carried out at Xiangya Hospital, Central South University. 110 participants with chronic insomnia were analyzed. Methods: This trial enrolled older patients who underwent total hip/knee arthroplasty and randomized them to receive intranasal dexmedetomidine (2.0 μg/kg) or saline daily at around 9 p.m. after surgery until discharge. The primary outcomes were subjective sleep quality assessed with the Leeds Sleep Evaluation Questionnaire (LSEQ). The secondary outcomes included the objective sleep quality measured with the Acti-graph, the Pittsburgh Sleep Quality Index (PSQI), the Insomnia Severity Index (ISI). The other outcomes included the incidence of delirium, levels of inflammatory factors, visual analog scale (VAS) pain scores, postoperative opioid consumption, and treatment-related adverse events. Results: 174 patients were screened for eligibility, and 110 were recruited and analyzed. The DEX group had significantly higher scores on both the LSEQ-Getting to sleep and LSEQ-Quality of Sleep at each time point compared to the placebo (p < 0.0001), The least squares (LS) mean difference in LSEQ-GTS score at T0 between placebo group and DEX group was 2 (95% CI, -1-6), p = 0.4071 and at T5 was -14 (95% CI, -17 to -10), p < 0.0001; The LS mean difference in the LSEQ-QOS score at T0 was -1 (95% CI, -4 to 1), p = 0.4821 and at T5 was -16 (95% CI, -21 to -10), p < 0.0001. The DEX group exhibited significant improvement in Total Sleep Time (TST), Sleep Onset Latency (SOL), and Sleep Efficiency (SE), at each time point after treatment compared to the placebo group (p < 0.0001). The PSQI and ISI scores in the DEX group were reduced after treatment (p < 0.001). No significant adverse events were reported with the use of dexmedetomidine. Conclusion and Implications: This study demonstrates that intranasal administration of dexmedetomidine improves postoperative sleep quality in older patients with chronic insomnia who undergo surgery, without increasing the incidence of adverse effects. Clinical Trial Registration: http://www.chictr.org.cn/, identifier ChiCTR2200057133.

The Beneficial Effect of Preoperative Dexmedetomidine in Controlling Postoperative Pain, Nausea, and Vomiting After Orthognathic Surgery: A Triple-blind Randomized Clinical Trial

PURPOSE

Controlling postoperative pain and nausea (PONV) following orthognathic surgery can be challenging. The aim of the study was to assess the efficacy of dexmedetomidine (DEX) in reducing pain and preventing nausea and vomiting in subjects undergoing orthognathic surgery.

METHODS

The authors implemented a triple-blinded, randomized clinical trial. Healthy adults with class III jaw deformity scheduled for bimaxillary orthognathic surgery were included. Subjects were randomized to the DEX or placebo groups. The DEX group received premedication with DEX 1 μg/kg IV over 10 minutes followed by a maintenance dose (0.2 μg/kg/hour) while the placebo group received normal saline. The primary outcome variables were postoperative pain, postoperative nausea, and postoperative vomiting . Pain was assessed using a visual analog scale at 1, 3, 6, 12, 18, and 24 hours, postoperatively). Nausea and vomiting were recorded throughout the postoperative period. Statistical analysis was performed using χ2, t test, and repeated measures ANOVA with a P value < .05 considered significant.

RESULTS

A total of 60 consecutive subjects with a mean age of 24.6 ± 3.5 years completed the study. There were 38 females (63.33%) and 22 males (36.66%). The mean visual analog scale was significantly lower in the DEX group at all time-points (P < .05). There was a significantly greater demand for rescue analgesics in the placebo group compared to the DEX group (P = .01). Fourteen subjects (46.7%) in the placebo group and one subject (3.3%) in the DEX group reported nausea (P < .001). Postoperative vomiting was not observed in any of the subjects.

CONCLUSION

Premedication with DEX can be considered a viable treatment option for reducing postoperative pain and postoperative nausea after bimaxillary orthognathic surgery.

Sublingual dexmedetomidine (BXCL501) reduces opioid withdrawal symptoms: findings from a multi-site, phase 1b/2, randomized, double-blind, placebo-controlled trial

Background: Like other alpha-2-adrenergic receptor agonists, dexmedetomidine may reduce the severity of opioid withdrawal but with fewer adverse cardiovascular effects.Objective: This study assessed the safety of sublingual dexmedetomidine (BXCL501) and its preliminary efficacy in treating opioid withdrawal (ClinicalTrials.gov: NCT04470050).Methods: Withdrawal was induced among individuals with physiological dependence on opioids via discontinuation of oral morphine (Days 1-5). Participants were randomized to receive placebo or active BXCL501: 30, 60, 90, 120, 180, and 240 μg twice daily (Days 6-12). Treatment-emergent adverse events (TEAEs) were the primary outcome measure. Secondary outcomes included the Clinical and Subjective Opiate Withdrawal Scales (COWS and SOWS-Gossop, respectively), and the Agitation and Calmness Evaluation Scale (ACES).Results: Of 225 participants enrolled, 90 discontinued during morphine stabilization. Post-BXCL501 randomization (Day 6) data were available from 135 participants (73% male), with 33% completing thru Day 12. In total, 36 subjects reported 1 or more TEAE. Higher doses of BXCL501 (i.e. 180 and 240 µg, twice daily) increased the frequency of: hypotension, orthostatic hypotension, and somnolence. TEAEs related to BXCL501 were mild or moderate in severity, except for one participant in the 120 µg condition whose orthostatic hypotension and bradycardia were classified as severe. Higher BXCL501 dose conditions (120, 180, and 240 µg) resulted in statistically significant reductions in COWS & SOWS scores. Mean ratings on the ACES were between 3 (mild), 4 (normal), and 5 (mild calmness), with few significant differences as a function of dose.Conclusions: These findings support the continued development of BXCL501 for the management of opioid withdrawal.

Drug delivery to the brain via the nasal route of administration: exploration of key targets and major consideration factors

Background

Cranial nerve-related diseases such as brain tumors, Alzheimer's disease, and epilepsy are serious diseases that continue to threaten human. Brain-related diseases are increasing worldwide, including in the United States and Korea, and these increases are closely related to the exposure to harmful substances and excessive stress caused by rapid industrialization and environmental pollution. Drug delivery to the brain is very important for the effective prevention and treatment of brain-related diseases. However, due to the presence of the blood-brain barrier and the extensive first-pass metabolism effect, the general routes of administration such as oral and intravenous routes have limitations in drug delivery to the brain. Therefore, as an alternative, the nasal-brain drug delivery route is attracting attention as a route for effective drug delivery to the brain.

Areas covered

This review includes physiological factors, advantages, limitations, current application status, especially in clinical applications, and the necessary factors for consideration in formulation development related to nasal-brain drug delivery.

Expert opinion

The nasal-brain drug delivery route has the advantage of enhancing drug delivery to the brain locally, mainly through the olfactory route rather than the systemic circulation. The nasal-brain lymphatic system has recently attracted attention, and it has been implied that the delivery of anticancer drugs to the brain nervous system is possible effectively. However, there are limitations such as low drug permeability, as well as nasal mucosa and the mucociliary system, as obstacles in nasal-brain drug delivery. Therefore, to overcome the limitations of nasal-brain drug delivery, the use of nanocarriers and mucoadhesive agents is being attempted. However, very few drugs have been officially approved for clinical application via the nasal-brain drug delivery route. This is probably because the understanding of and related studies on nasal-brain drug delivery are limited. In this review, we tried to explore the major considerations and target factors in drug delivery through the nasal-brain route based on physiological knowledge and formulation research information. This will help to provide a mechanistic understanding of drug delivery through the nasal-brain route and bring us one step closer to developing effective formulations and drugs in consideration of the key factors for nasal-brain drug delivery.

What's New in Intravenous Anaesthesia? New Hypnotics, New Models and New Applications

New anaesthetic drugs and new methods to administer anaesthetic drugs are continually becoming available, and the development of new PK-PD models furthers the possibilities of using arget controlled infusion (TCI) for anaesthesia. Additionally, new applications of existing anaesthetic drugs are being investigated. This review describes the current situation of anaesthetic drug development and methods of administration, and what can be expected in the near future.

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.

Intranasal Dexmedetomidine in Elderly Patients (Aged > 65 Years) During Maxillofacial Surgery: Sedative Properties and Safety Analysis

PURPOSE

Light sedation rather than intravenous sedation is preferred when patients have a low heart rate and blood pressure during maxillofacial surgery. Intranasal administration of dexmedetomidine is reported to be efficacious and safe in adults. However, dexmedetomidine could be unsuitable for routine clinical use in elderly patients because many of these patients take β-blockers, which increase the cardiovascular effects of dexmedetomidine. The objectives of the study were to evaluate the sedative properties and safety of intranasal dexmedetomidine, regardless of concurrent β-blocker treatment, in elderly patients who underwent maxillofacial surgery.

METHODS

This study was a retrospective analysis of 535 patients aged > 65 years (American Society of Anesthesiologists physical status I or II) who were undergoing maxillofacial surgery. Very anxious patients and those with hypertension received intranasal 1 µg/kg dexmedetomidine through an intranasal mucosal atomization device before anesthesia (local ropivacaine).

RESULTS

Intranasal administration of dexmedetomidine decreased the requirement for midazolam before surgery (18 of 252 vs 63 of 283, P < .0001), but increased the requirement for norepinephrine (102 of 252 vs 8 of 283, P < .0001) during or after the surgery. A combination of a β-blocker and intranasal administration of dexmedetomidine reduced the hemodynamic parameters for an extended period. Intranasal administration of dexmedetomidine resulted in bradycardia and hypotension, regardless of concurrent β-blocker treatment.

CONCLUSIONS

Intranasal 1 µg/kg dexmedetomidine was associated with a high sedation score during the operation, but also with bradycardia and hypotension.

Dexmedetomidine as an Analgesic Agent with Neuroprotective Properties: Experimental and Clinical Aspects

Dexmedetomidine (Dexdor or Precedex®) is considered as a sedative agent which is widely used as an adjuvant in general anesthesia and critical care practice. There is extensive evidence indicating its neuroprotective properties especially in various ischemic and hemorrhagic brain injury models of animals. Clinical trials have shown that dexmedetomidine (DEX) can improve the outcome of intensive care unit (ICU) patients. Also, DEX is appropriate as a non-opioid analgesic therapy whenever minimizing opioid-related side effects is necessary. The present article reviews the recent advances in the use of DEX as a neuroprotective agent in both animal and human studies including newest findings about the mechanism of the drug as well as analgesic efficacy of this drug at all perioperative stages. In spite of the beneficial effects of the drug on the nervous system, there are potential adverse effects, such as hypotension and bradycardia, which can be treated pharmacologically and must be taken into consideration by clinicians.

Comparison of dexmedetomidine with midazolam for dental surgery: A systematic review and meta-analysis

INTRODUCTION

Dexmedetomidine and midazolam have become important approaches for the sedation of dental surgery. However, the comparison of these 2 drugs for the sedation of dental surgery has not been well established. We conduct a systematic review and meta-analysis to evaluate the efficacy of dexmedetomidine versus midazolam for dental surgery.

METHODS

PubMed, Embase, and the Cochrane Central Register of Controlled Trials are searched. Randomized controlled trials (RCTs) assessing the influence of dexmedetomidine versus midazolam on dental surgery are included. Two investigators independently have searched articles, extracted data, and assessed the quality of included studies. Meta-analysis is performed using the random-effect model.

RESULTS

Five RCTs and 420 patients are included in the meta-analysis. Compared with midazolam intervention for dental surgery, dexmedetomidine intervention has similar lowest SpO2, lowest heart rate and lowest systolic blood pressure, duration of surgery, and total volume of local anesthetic, but is associated with stable and reduced lowest diastolic blood pressure.

CONCLUSIONS

Similar benefits of dexmedetomidine and midazolam intervention are observed for the sedation of dental surgery in terms of SpO2, heart rate, systolic blood pressure, and the volume of local anesthetic, but dexmedetomidine may result in more stable diastolic blood pressure.

Comparison of dexmedetomidine with chloral hydrate as sedatives for pediatric patients: A systematic review and meta-analysis

BACKGROUND

Dexmedetomidine (Dex) and chloral hydrate (CH) are the most frequently used sedative agents in pediatric patients. We aimed to systematically review the literature comparing the efficacy and safety of Dex and CH for sedation in pediatric patients.

METHODS

Seven electronic databases and 3 clinical trial registry platforms were searched for articles published prior to October 2019. Randomized controlled trials (RCTs) evaluating the efficacy and safety of Dex versus CH for sedation in children were examined by 2 reviewers. The extracted information included the success rate of sedation, sedation latency, sedation duration, sedation recovery time, and adverse events. Moreover, the extracted data included 5 subgroups: the effects of 1, 1.5, 2, 2.5, and 3 μg/kg doses of Dex were compared with the effect of CH on the success rate of sedation. We also formed separate subgroups for different types of adverse events (incidence of vomiting, hypotension, bradycardia, etc). The outcomes were analyzed by Review Manager 5.3 software and are expressed as relative risks (RR) or the mean difference (MD) with the 95% confidence interval (CI). Heterogeneity was assessed with I-squared (I) statistics.

RESULTS

A total of 15 RCTs involving 2128 children with Dex versus CH for sedation were included in the meta-analysis. The dose range of Dex ranged from 1 to 3 μg/kg. Compared with CH, the Dex group had a significantly higher success rate of sedation (RR = 1.14, 95% CI [1.05, 1.25], I = 79%, P = .003). Additionally, subgroup analysis revealed that there was no significant difference in the success rate of sedation between the CH group and the 1, 1.5, 2.5, and 3 μg/kg Dex groups; only the 2 μg/kg Dex group had a significantly higher success rate than the CH group (RR = 1.15, 95% CI [1.03, 1.29], I = 80%, P = .02). There was no significant difference in the number of subjects who required 2 doses or the duration of sedation between the CH and Dex groups. Furthermore, compared with the Dex group, the CH group had a significantly longer sedation latency (MD = -3.54, 95% CI [-5.94, -1.15], I = 95%, P = .004), sedation recovery time (MD = -30.08, 95% CI [-46.77, -13.39], I = 99%, P = .0004), and total time from sedative administration to discharge (MD = -12.73, 95% CI [-15.48, -9.97], I = 0%, P < .05), as well as a higher number of adverse events in total (RR = 0.25, 95% CI [0.11, 0.61], I = 89%, P = .002). Moreover, the subgroup analysis of adverse events revealed that CH was associated with higher risks of vomiting (RR = 0.07, 95% CI [0.03, 0.17], I = 0%, P < .0001), crying or resisting (RR = 0.22, 95% CI [0.07, 0.71], I = 60%, P = .01), and cough (RR = 0.15, 95% CI [0.05, 0.44], I = 0%, P = .0006); there was no significant difference in the risk of hypotension, supplemental oxygen, or respiratory events between CH and Dex. However, Dex was associated with a higher risk of bradycardia (RR = 4.08, 95% CI [1.63, 10.21], I = 0%, P = .003).

CONCLUSIONS

Dex is an appropriate effective alternative to CH for sedation in pediatrics. However, considering the possibility of bradycardia, Dex should be used with caution.

Intranasal dexmedetomidine combined with local anesthesia for conscious sedation during breast lumpectomy: A prospective randomized trial

Breast lumpectomy is usually performed under general or local anesthesia. To the best of our knowledge, whether conscious sedation with intranasal dexmedetomidine and local anesthesia is an effective anesthetic technique has not been studied. Thus, the present study aimed to investigate the effectiveness of conscious sedation with intranasal dexmedetomidine combined with local anesthesia in breast lumpectomy, and to identify its optimal dose. A prospective randomized, double-blinded, placebo-controlled, single-center study was designed, and patients undergoing breast lumpectomies were recruited based on the inclusion and exclusion criteria. All patients were randomly allocated to four groups: i) Local anesthesia with 0.9% intranasal saline (placebo); local anesthesia with ii) 1 µg.kg⁻¹; iii) 1.5 µg.kg⁻¹; or iv) 2 µg.kg⁻¹ intranasal dexmedetomidine. The sedation status, pain relief, vital signs, adverse events, and satisfaction of patient and surgeon were recorded. Patients in the three dexmedetomidine groups were significantly more sedated and experienced less pain compared with the placebo group 45 min after intranasal dexmedetomidine administration and during 30 min in the post-anesthesia care unit. Patients in the 1.5 µg.kg⁻¹ group were more sedated compared with the 1 µg.kg⁻¹ group (without reaching statistical significance), whereas the 1.5 µg.kg⁻¹ group exhibited a similar level of sedation 45 min after intranasal dexmedetomidine administration compared with the 2 µg.kg⁻¹ group. In addition, patients in the 1 and 1.5 µg.kg⁻¹ group experienced no adverse hemodynamic effects. Patient and surgeon satisfaction were greater in the 1.5 µg.kg⁻¹ group compared with the 1 and 2 µg.kg⁻¹ groups. Taken together, the results of the present study suggested that conscious sedation with intranasal dexmedetomidine and local anesthesia may be an effective anesthetic for breast lumpectomy surgery, and that the optimal dose for intranasal dexmedetomidine administration may be 1.5 µg.kg⁻¹, as it resulted in good sedation and patient satisfaction without adverse effects.

Intranasal dexmedetomidine in elderly subjects with or without beta blockade: a randomised double-blind single-ascending-dose cohort study

BACKGROUND

The aim of this double-blind, placebo-controlled, single-ascending-dose study was to determine the safety and tolerability of intranasal dexmedetomidine in the elderly.

METHODS

We randomly assigned 48 surgical patients ≥65 yr of age to receive single intranasal doses of dexmedetomidine or placebo (5:1 ratio) in four sequential dose cohorts: 0.5, 1.0, 1.5, and 2.0 μg kg-1. Each dose cohort comprised two groups of six subjects: a group of subjects using β-blockers and a group not taking β-blockers. Vital signs and sedation depth (Modified Observer's Assessment of Alertness and Sedation [MOAA/S] and bispectral index) were measured for 2 h after administration. Blood samples were taken to determine dexmedetomidine plasma concentrations.

RESULTS

One subject (1.0 μg kg-1) had acute hypotension requiring ephedrine. Systolic arterial BP decreased >30% in 15 of 40 subjects (37.5%) receiving dexmedetomidine, lasting longer than 5 min in 11 subjects (27.5%). The MAP decreased >30% (>5 min) in 10%, 20%, 50%, and 30% of subjects receiving dexmedetomidine 0.5, 1.0, 1.5, and 2.0 μg kg-1, respectively, irrespective of β-blocker use. HR decreased 10-26%. MOAA/S score ≤3 occurred in 18 (45%) subjects; eight (20%) subjects receiving dexmedetomidine showed no signs of sedation. Tmax was 70 min. Cmax was between 0.15 ng ml-1 (0.5 μg kg-1) and 0.46 ng ml-1 (2.0 μg kg-1).

CONCLUSIONS

Intranasal dexmedetomidine in elderly subjects had a sedative effect, but caused a high incidence of profound and sustained hypotension irrespective of β-blocker use. The technique is unsuitable for routine clinical use.

CLINICAL TRIAL REGISTRATION

NTR5513 (The Netherlands Trial Registry 5513).

Clinical Pharmacokinetics and Pharmacodynamics of Dexmedetomidine

Dexmedetomidine is an α₂-adrenoceptor agonist with sedative, anxiolytic, sympatholytic, and analgesic-sparing effects, and minimal depression of respiratory function. It is potent and highly selective for α₂-receptors with an α₂:α₁ ratio of 1620:1. Hemodynamic effects, which include transient hypertension, bradycardia, and hypotension, result from the drug’s peripheral vasoconstrictive and sympatholytic properties. Dexmedetomidine exerts its hypnotic action through activation of central pre- and postsynaptic α₂-receptors in the locus coeruleus, thereby inducting a state of unconsciousness similar to natural sleep, with the unique aspect that patients remain easily rousable and cooperative. Dexmedetomidine is rapidly distributed and is mainly hepatically metabolized into inactive metabolites by glucuronidation and hydroxylation. A high inter-individual variability in dexmedetomidine pharmacokinetics has been described, especially in the intensive care unit population. In recent years, multiple pharmacokinetic non-compartmental analyses as well as population pharmacokinetic studies have been performed. Body size, hepatic impairment, and presumably plasma albumin and cardiac output have a significant impact on dexmedetomidine pharmacokinetics. Results regarding other covariates remain inconclusive and warrant further research. Although initially approved for intravenous use for up to 24 h in the adult intensive care unit population only, applications of dexmedetomidine in clinical practice have been widened over the past few years. Procedural sedation with dexmedetomidine was additionally approved by the US Food and Drug Administration in 2003 and dexmedetomidine has appeared useful in multiple off-label applications such as pediatric sedation, intranasal or buccal administration, and use as an adjuvant to local analgesia techniques.

Practice Guidelines for Moderate Procedural Sedation and Analgesia 2018

Supplemental Digital Content is available in the text.

omparative Evaluation of the Intranasal Spray Formulation of Midazolam and Dexmedetomidine in Patients Undergoing Surgical Removal of Impacted Mandibular Third Molars: A Split Mouth Prospective Study

Purpose

The purpose of this prospective randomized single blinded split mouth study was to conduct a comparative evaluation of the efficacy of intranasal atomised spray formulation of Dexmedetomidine with Midazolam in patients undergoing surgical removal of bilaterally impacted mandibular third molars.

Methods

This prospective study was conducted in twenty volunteers. Each volunteer underwent the surgical removal of an impacted mandibular third molar at two separate appointments at an interval of two weeks. The first third molar surgery was conducted using either intranasal Midazolam (Group M) or intranasal Dexmedetomidine (Group D). At the second appointment the surgical procedure was performed using the sedative agent not used at the first appointment. The primary testing outcome variables were Plasma oxygen saturation (SpO2), pulse and blood pressure and Modified Observer's Assessment of Alertness/Sedation (OAA/S) scale. These were recorded at predetermined intervals starting 10 min before the administration of local anaesthesia and continued up to 10 min after completion of the procedure. In addition surgeon's opinion regarding the patient cooperation, event amnesia, post operative nausea & vomiting were obtained.

Results

The sample composed of twenty patients (M = 9 and F = 11). There was statistically no significant difference between Group M and Group D with respect to mean SpO2. Minor differences were however noted at 20 and 30 min after sedation. There was no significant difference between the groups with respect to mean pulse rate, blood pressure, OAA/S, event amnesia, post operative nausea and vomiting and patient cooperation.

Conclusion

We conclude that Midazolam and Dexmedetomidine are equivalent and can be used in minor oral surgery with minimal complications. These drugs can be used intranasally using nasal atomization device in routine outpatient basis in otherwise normal healthy but anxious patients. All procedures must however be performed in the presence of an anaesthesiologist and with ready availability of emergency drugs and equipment.

Intranasal dexmedetomidine in termination of first trimester pregnancy of suction evacuation

BACKGROUND AND AIM

Deep sedation without intubation for termination of first trimester pregnancy of suction evacuation entails use of sedatives such as propofol or a combination of propofol and sulfentanil, with unwanted complications. Dexmedetomidine is an α2-adrenoreceptor agonist which provides sedation, anxiolysis and analgesia, without any of the complications associated with the popular sedatives.

METHODS

A total number of 90 patients were randomized to three groups: 1. group P, treated with intranasal saline, intravenous saline and propofol; 2. group DP, treated with intranasal dexmedetomidine, intravenous saline and propofol; and 3. group SP, treated with intranasal saline, intravenous sulfentanil and propofol. The primary outcome was the consumption of propofol, and the secondary outcomes were numeric rating scale (NRS) anxiety score, NRS pain score of uterine cramping, amount of blood loss, use of oxytocin and NRS satisfaction scores of obstetric and gynecological (ob/gyn) physicians and patients.

RESULTS

The consumption of propofol, NRS pain score of uterine cramping after surgery, NRS anxiety score, and amount of blood loss in group DP were significantly lower than those in group P and group SP. Ob/gyn physicians' satisfaction score in group DP was significantly higher compared with group SP and group P.

CONCLUSION

Sedation with intranasal dexmedetomidine (1 μg/kg) provided effective analgesia and anxiolysis, reduced consumption of propofol and lower blood loss in termination of first trimester pregnancy of suction evacuation. Compared with propofol or the combination of propofol and sulfentanil, intranasal dexmedetomidine was associated with higher satisfaction score of ob/gyn physicians. No unforeseen perioperative respiratory and cardiovascular adverse events occurred.

REGISTRY NUMBER FOR CLINICAL TRIALS

ChiCTR-IPR-14005654.

Dexmedetomidine in perioperative acute pain management: a non-opioid adjuvant analgesic

Many nociceptive, inflammatory, and neuropathic pathways contribute to perioperative pain. Although opioids have long been a mainstay for perioperative analgesia, other non-opioid therapies, and dexmedetomidine, in particular, have been increasingly used as part of a multimodal analgesic regimen to provide improved pain control while minimizing opioid-related side effects. This article reviews the evidence supporting the preoperative, intraoperative, and postoperative efficacy of dexmedetomidine as an adjuvant, and the efficacy of intravenous, spinal canal, and nerve block analgesia with dexmedetomidine for perioperative acute pain treatment. While there have not been any large-scale clinical trials conducted, the current body of evidence suggests that dexmedetomidine is suitable for use as an adjuvant analgesic at all perioperative stages. However, there are potential adverse effects, such as hypotension and bradycardia, which must be taken into consideration by clinicians.

Risks and benefits of pre-operative dexmedetomidine in oral and maxillofacial surgeries: a systematic review

INTRODUCTION

Oral and maxillofacial surgeries might induce anxiety and pain to the patients. Sedative agents are one of the best ways for eliminating such consequences. Dexmedetomidine (DEX) is a recent sedative agent which presents higher sedative quality with greater specificity than other drugs. The aim of present paper is to evaluate the risks and benefits of administrating DEX during oral and maxillofacial surgeries by reviewing high quality released articles. Areas covered: Searches on PubMed, Scopus and Web of Science databases were completed with focus on randomized controlled trials (RCT). Related articles, from 2000 to 2015, were selected based on inclusion criteria and quality assessments factors. Full texts of the selected articles were screened and their significant information were gathered for judgments. Expert opinion: 17 RCTs on a total of 765 patients were screened. Some of the difficulties during reviewing the articles were: different pharmacokinetic and pharmacodynamics of drugs when combined with DEX, different time spots and method of monitoring, including studies on both minor and major surgeries for better data collection. Recent researches are going to focus on application of DEX for in-office procedures because of its desirable properties. Nevertheless, the analgesic and amnesic features of DEX are still questionable.

Dexmedetomidine versus Midazolam in Procedural Sedation. A Systematic Review of Efficacy and Safety

Objectives

To systematically review the literature comparing the efficacy and safety of dexmedetomidine and midazolam when used for procedural sedation.

Materials and Methods

We searched MEDLINE, EMBASE and COCHRANE for clinical trials comparing dexmedetomidine and midazolam for procedural sedation up to June 20, 2016. Inclusion criteria: clinical trial, human subjects, adult subjects (≥18 years), article written in English, German, French or Dutch, use of study medication for conscious sedation and at least one group receiving dexmedetomidine and one group receiving midazolam. Exclusion criteria: patients in intensive care, pediatric subjects and per protocol use of additional sedative medication other than rescue medication. Outcome measures for efficacy comparison were patient and clinician satisfaction scores and pain scores; outcome measures for safety comparison were hypotension, hypoxia, and circulatory and respiratory complications.

Results

We identified 89 papers, of which 12 satisfied the inclusion and exclusion criteria; 883 patients were included in these studies. Dexmedetomidine was associated with higher patient and operator satisfaction than midazolam. Patients receiving dexmedetomidine experienced less pain and had lower analgesic requirements. Respiratory and hemodynamic safety were similar.

Conclusions

Dexmedetomidine is a promising alternative to midazolam for use in procedural sedation. Dexmedetomidine provides more comfort during the procedure for the patient and clinician. If carefully titrated, the safety profiles are similar.

Efficacy of Dexmedetomidine as a Sole Sedative Agent in Small Diagnostic and Therapeutic Procedures: A Systematic Review

Dexmedetomidine is an upcoming agent with sedative, anxiolytic, and analgesic properties. This review summarizes empirical evidence for the efficacy of dexmedetomidine as a sole sedative agent, and its effectiveness for small diagnostic and therapeutic procedure, in comparison with other frequently used sedatives. All randomized controlled trials on the effect of dexmedetomidine were reviewed. Pain level, patient satisfaction, operator satisfaction, procedure duration, recovery time, and hemodynamic and respiratory characteristics were examined. A total of 1993 patients (1,621 adults; 372 children) from 35 studies were included. In the adult studies, dexmedetomidine yielded significantly lower pain levels compared to the other sedatives (in 31.25% of the included studies) and significantly more patient satisfaction (68.2%). In studies on children, more favorable results concerning respiratory safety and the level of adequate sedation were found compared to the control sedatives. Implications for future studies are discussed.

Intranasally Administered Adjunctive Dexmedetomidine Reduces Perioperative Anesthetic Requirements in General Anesthesia

PURPOSE

Intranasal dexmedetomidine is an effective sedative for premedication and is regularly used to reduce preoperative tension and anxiety in children. This study aimed to assess the effect of intranasally adjunctive dexmedetomidine on perioperative sedative and analgesic requirements in adults.

MATERIALS AND METHODS

Patients were randomly divided into four groups to receive preoperative administration of saline, intranasal dexmedetomidine 1 μg/kg and 2 μg/kg, and intravenous dexmedetomidine 1 μg/kg, respectively. Propofol and remifentanil were target-controlled infused to maintain intraoperative bispectral index at 45-55 and blood pressure at baseline value±20%. Sufentanil was administered to maintain postoperative visual analogue scale ≤3. Perioperative anesthetics requirements were compared using nonparametric tests.

RESULTS

Intranasal dexmedetomidine significantly attenuated propofol requirements for anesthesia induction and maintenance in a dose-dependent manner. Patients given intranasal dexmedetomidine 2 μg/kg required less remifentanil for anesthesia maintenance. The first postoperative request for sufentanil analgesia was delayed in patients given intranasal dexmedetomidine 2 μg/kg. The anesthetics-sparing effect of intranasal dexmedetomidine was significantly weaker than intravenous dexmedetomidine at the same dose of 1 μg/kg. The incidences of adverse events, including hemodynamic instability and delayed recovery, were comparable with and without intranasal dexmedetomidine.

CONCLUSION

Intranasal administration of dexmedetomidine can reduce perioperative anesthetic requirements, and a dose of dexmedetomidine 2 μg/kg produces a better effect in adults. The anesthetics-sparing effect of intranasal dexmedetomidine 1 μg/kg is less than that with the same intravenous dose of dexmedetomidine.

Intranasal dexmedetomidine in combination with patient-controlled sedation during upper gastrointestinal endoscopy: a randomised trial

BACKGROUND

Sedation using intranasal dexmedetomidine is a convenient and well-tolerated technique. This study evaluated the sedative efficacy of intranasal dexmedetomidine in combination with patient-controlled sedation (PCS) for upper gastrointestinal endoscopy.

METHODS

In this double-blind, randomised, controlled trial, 50 patients received either intranasal dexmedetomidine 1.5 μg/kg (dexmedetomidine group) or intranasal saline (placebo group) 1 h before the procedure. PCS with propofol and alfentanil was provided for rescue sedation. Additional sedative consumption, perioperative sedation scores using Observer's Assessment of Alertness/Sedation (OAA/S) scale, recovery, vital signs, adverse events and patient satisfaction were assessed.

RESULTS

Total consumption of PCS propofol and alfentanil was significantly less in the dexmedetomidine than placebo group with a mean difference of -13.8 mg propofol (95% confidence interval -27.3 to -0.3) and -34.5 μg alfentanil (95% confidence interval -68.2 to -0.7) at the completion of the procedure (P = 0.044). Weighted areas under the curve (AUCw ) of OAA/S scores were significantly lower in the dexmedetomidine group before, during and after procedures (P < 0.001, P = 0.024 and P = 0.041 respectively). AUCw of heart rate and systolic blood pressure were also significantly lower during the procedure (P = 0.007 and P = 0.022 respectively) with dexmedetomidine. There was no difference in recovery, side effects or satisfaction.

CONCLUSION

Intranasal dexmedetomidine with PCS propofol and alfentanil confers deeper perioperative clinical sedation with significantly less use of additional sedatives during upper gastrointestinal endoscopy.

New therapeutic uses for an alpha2 adrenergic receptor agonist--dexmedetomidine in pain management

Dexmedetomidine was initially approved for clinical use as a sedative. Its development in pain management has been limited. Dexmedetomidine has analgesic effects and analgesic-sparing properties, especially for patients with obstructed airways. Mixing dexmedetomidine with local anesthetics is a promising new avenue to enhance local anesthetics' effectiveness. Peripheral, spinal and supraspinal α(2A)-ARs are responsible for the analgesic function of dexmedetomidine. Animal studies have shown that antinociceptive synergism results from co-application of dexmedetomidine and opioids or local anesthetics. Dexmedetomidine has potential adverse effects such as hypotension and bradycardia. Therefore, dexmedetomidine is contraindicated for patients suffering from bradycardia or using β-adrenergic antagonists. Clinical trials of dexmedetomidine in chronic pain or hyperalgesia are lack.