Dexmedetomidine in Children

Melatonin vs. dexmedetomidine for sleep induction in children before electroencephalography

Background and objectives

In children requiring electroencephalography (EEG), sleep recording can provide crucial information. As EEG recordings during spontaneous sleep are not always possible, pharmacological sleep-inducing agents are sometimes required. The aim of the study was to evaluate safety and efficacy of melatonin (Mel) and dexmedetomidine (Dex; intranasal and sublingual application) for sleep induction prior to EEG.

Methods

In this prospective randomized study, 156 consecutive patients aged 1-19 years were enrolled and randomized by draw into melatonin group (Mel; n = 54; dose: 0.1 mg/kg), dexmedetomidine (Dex) sublingual group (DexL; n = 51; dose: 3 mcg/kg) or dexmedetomidine intranasal group (DexN; n = 51; dose: 3 mcg/kg). We compared the groups in several parameters regarding efficacy and safety and also carried out a separate analysis for a subgroup of patients with complex behavioral problems.

Results

Sleep was achieved in 93.6% of participants after the first application of the drug and in 99.4% after the application of another if needed. Mel was effective as the first drug in 83.3% and Dex in 99.0% (p < 0.001); in the subgroup of patients with complex developmental problems Mel was effective in 73.4% and Dex in 100% (p < 0.001). The patients fell asleep faster after intranasal application of Dex than after sublingual application (p = 0.006). None of the patients had respiratory depression, bradycardia, desaturation, or hypotension.

Conclusions

Mel and Dex are both safe for sleep induction prior to EEG recording in children. Dex is more effective compared to Mel in inducing sleep, also in the subgroup of children with complex behavioral problems.

Clinical Trial Registration

Dexmedetomidine and Melatonin for Sleep Induction for EEG in Children, NCT04665453.

Comparative evaluation of nebulised dexmedetomidine vs fentanyl for the treatment of post-dural puncture headache (PDPH) in parturients after caesarean section under spinal anaesthesia: A randomised controlled study

Background and Aims

The incidence of post-dural puncture headache (PDPH) following spinal anaesthesia in the obstetric population is around 0.5%-2%. Hydration, bed rest, caffeine, paracetamol, non-steroid anti-inflammatory drugs, epidural blood patches, etc., are the various modalities used for its management. This study aims to compare nebulised dexmedetomidine versus fentanyl for the treatment of PDPH in parturients after caesarean section under spinal anaesthesia.

Methods

Ninety obstetric patients aged 18-35 years with American Society of Anesthesiologists (ASA) physical status II/III and suffering from PDPH as per the criteria of the International Headache Society after caesarean section under spinal anaesthesia were recruited in this double-blinded randomised study. Patients were randomised to Group D (dexmedetomidine 1 µg/kg nebulisation), Group F (fentanyl 1 µg/kg nebulisation), and Group S (saline nebulisation 4mL). The nebulisation was done 12 hourly for 72 hours. Assessment parameters included pain score and the requirement of additional treatment such as paracetamol, caffeine, and epidural blood patch. Analysis of variance test was used for continuous quantitative variables, and the Kruskal-Wallis test was used for quantitative discrete data.

Results

The pain scores at 1, 6, 12, 24, 48, and 72 hours following nebulisation were significantly lower in Group D in comparison to groups F and S (P < 0.001). The number of patients requiring additional analgesic therapy was lower in Group D in comparison to patients in other groups (P < 0.001).

Conclusion

Dexmedetomidine nebulisation resulted in effective reduction in PDPH symptoms and pain scores. Nebulisation with fentanyl did not alleviate PDPH symptoms when compared to the control group.

Effect of different doses of dexmedetomidine as an adjuvant to lignocaine nebulization: A comparative study during awake flexible fiberoptic bronchoscopy

Background and Aims

Mild to moderate sedation during bronchoscopy is essential for patient safety, comfort during and after the procedure, and to facilitate the performance of the bronchoscopist. Dexmedetomidine is a highly selective, centrally acting α-2 agonist used to provide conscious sedation during various procedures. The aim of this study was to compare the efficacy of three different doses of dexmedetomidine nebulization as an adjuvant to lignocaine during bronchoscopy.

Material and Methods

Ninety American Society of Anesthesiologists physical status I/II patients, aged from 18 to 60 years, scheduled for an elective bronchoscopy, were recruited. They were divided into three groups: 30 patients in each group. Group I: The patient was nebulized with a mixture of 4 ml of 4% lignocaine and dexmedetomidine 0.5 μg/kg. Group II: The patient was nebulized with a mixture of 4% lignocaine, 4 ml, and dexmedetomidine, 1 μg/kg. Group III: The patient was nebulized with 4% lignocaine 4 ml and dexmedetomidine 1.5 μg/kg.

Results

The mean cough score was (1.17 ± 0.37), (1.40 ± 0.49), and (1.70 ± 0.75) in group III, group II, and group I, respectively. A significant difference was found between the groups. Patients were more comfortable with a statistically significant difference in the comfort score in group III as compared to group II and group I.

Conclusion

Dexmedetomidine nebulization in a dose of 1.5 μg/kg (compared to 1 μg/kg or 0.5 μg/kg) as an adjuvant to lignocaine, provides better bronchoscopy conditions and patient satisfaction.

The effect of age on outpatient pediatric procedural sedation with intranasal dexmedetomidine and oral midazolam

Procedural sedation for diagnostic examination is a common practice in children. The study aims to analyze the sedative effect and safety of intranasal dexmedetomidine combined with oral midazolam in outpatient pediatric procedural sedation across different age groups and to assess the incidence of sedation failure. From February 2021 to September 2021, children who underwent procedural sedation were retrospectively enrolled. The children were divided into 4 groups based on age: the infant group (0 to 1 year old), toddler group (1 to 3 years old), preschool group (3 to 6 years old), and school-age group (6 to 12 years old). Two-mcg/kg intranasal dexmedetomidine and 0.5-mg/kg oral midazolam were used for sedation. The sedation success rate after rescue, sedation success rate, onset time of sedation, and the sedation time were recorded. The incidence of adverse events and the risk factors for sedation failure were also analyzed. A total of 4758 patients were identified. After exclusion, 3149 patients were ultimately enrolled. The combination of 2-mcg/kg intranasal dexmedetomidine and 0.5-mg/kg oral midazolam resulted in a total success rate of 99.7% and a sedation success rate of 91.4%. The sedation success rate varied among the four groups: 90.2% in the infant group, 93.1% in the toddler group, 92.7% in the preschool group, and 78.4% in the school-age group. The sedation success rate was significantly lower in the school-age group compared to the other three groups (P < 0.001). The onset time of sedation was shorter in infant (22 min, IQR: 18-28 min, P < 0.001) and longer in the school-age group (30 min, IQR: 25-35 min, P < 0.05). Additionally, the infants had a longer sedation time (110 min, IQR: 90-135 min, P < 0.001) and a higher rate of delayed recovery (27.5%, all P < 0.001). The incidence of adverse events was low (4.70%), which bradycardia (2.03%) being the most common. Age (0-1 year and > 6 years), weight, ASA class II, and history of failed sedation were identified as risk factors of sedation failure.   Conclusion: Intranasal administration of 2-mcg/kg dexmedetomidine combined with oral administration of 0.5-mg/kg midazolam was found to be efficient and safety for pediatric procedural sedation. Different age groups of children exhibited distinct sedation characteristics, and age was identified as a risk factor affecting the efficacy of sedation. What is Known: • Procedural sedation for diagnostic examination is a common practice in children. • The combination of dexmedetomidine with midazolam can improve sedative effects. What is New: • The success rate of sedation using a combination of 2-mcg/kg intranasal dexmedetomidine and 0.5-mg/kg oral midazolam was significantly lower in school-age children as compared to infants, toddlers, and preschoolers. • The onset time of sedation increased with age, and the sedation time was found to be longer in infant patients.

Impact of Dexmedetomidine Infusion on Opioid and Benzodiazepine Doses in Ventilated Pediatric Patients in the Cardiac Intensive Care Unit

INTRODUCTION

Dexmedetomidine (DEX) is frequently used as an adjunct agent for prolonged sedation in the intensive care unit (ICU), though its effect on concomitant opioids or benzodiazepines infusions is unclear. We explored the impact of DEX on concomitant analgosedation in a cohort of ventilated pediatric patients in a cardiac ICU, with stratification of patients according to duration of ventilation (< 5 versus ≥ 5 days) following DEX initiation.

METHODS

We conducted a retrospective analysis on ventilated patients receiving a DEX infusion ≥ 24 h and at least one other sedative/analgesic infusion (January 2011-June 2021). We evaluated trends of daily doses of opioids and benzodiazepines from 24 h before to 72 h following DEX initiation, stratifying patients based on ventilation duration after DEX initiation (< 5 versus ≥ 5 days).

RESULTS

After excluding 1146 patients receiving DEX only, 1073 patients were included [median age 234 days (interquartile range 90, 879)]. DEX was associated with an opioid infusion in 99% of patients and a benzodiazepine infusion in 62%. Among patients ventilated for < 5 days (N = 761), opioids increased in the first 24 h following DEX initiation [+ 1.12 mg/kg/day (95% CI 0.96, 1.23), P < 0.001], then decreased [- 0.90 mg/kg/day (95% CI - 0.89, - 0.71), P < 0.001]; benzodiazepines slowly decreased [- 0.20 mg/kg/day (95% CI - 0.21, - 0.19), P < 0.001]. Among patients ventilated for ≥ 5 days (N = 312), opioid administration doubled [+ 2.09 mg/kg/day (95% CI 1.82, 2.36), P < 0.001] in the first 24 h, then diminished minimally [- 0.18 mg/kg/day (95% CI - 0.32, - 0.04), P = 0.015] without returning to baseline; benzodiazepine administration decreased minimally [- 0.03 mg/kg/day (95% CI - 0.05, - 0.01), P = 0.010]. Similar trends were confirmed when adjusting for age, gender, surgical complexity, recent major invasive procedures, duration of mechanical ventilation before DEX initiation, extubation within 72 h following DEX initiation, mean hourly DEX dose, and use of neuromuscular blocking infusion.

CONCLUSION

While in patients ventilated < 5 days opioids initially increased and then quickly decreased in the 72 h following DEX initiation, among patients ventilated ≥ 5 days opioids doubled, then decreased only minimally; benzodiazepines decreased minimally in both groups, although more slowly in the long-ventilation cohort. These findings may inform decision-making on timing of DEX initiation in ventilated patients already being treated with opioid or benzodiazepine infusions.

Pain Management in Children Admitted to the Emergency Room: A Narrative Review

Pain is a biopsychosocial experience characterized by sensory, physiological, cognitive, affective, and behavioral components. Both acute and chronic pain can have short and long-term negative effects. Unfortunately, pain treatment is often inadequate. Guidelines and recommendations for a rational approach to pediatric pain frequently differ, and this may be one of the most important reasons for the poor attention frequently paid to pain treatment in children. This narrative review discusses the present knowledge in this regard. A literature review conducted on papers produced over the last 8 years showed that although in recent years, compared to the past, much progress has been made in the treatment of pain in the context of the pediatric emergency room, there is still a lot to do. There is a need to create guidelines that outline standardized and easy-to-follow pathways for pain recognition and management, which are also flexible enough to take into account differences in different contexts both in terms of drug availability and education of staff as well as of the different complexities of patients. It is essential to guarantee an approach to pain that is as uniform as possible among the pediatric population that limits, as much as possible, the inequalities related to ethnicity and language barriers.

Determination of the ED90 of Dexmedetomidine Infusion to Prevent Emergence Agitation in Children Undergoing Dental Rehabilitation With Sevoflurane Anesthesia: A Biased-Coin Up-and-Down Sequential Allocation Trial

BACKGROUND

Emergence agitation (EA) is an adverse complication during early recovery from sevoflurane anesthesia. Continuous intravenous infusion of dexmedetomidine (DEX) is commonly used for EA prevention. However, a wide dose range is used for preventing EA, and the optimal dose remains unknown. This study was aimed at determining the optimal dose (the 90% effective dose [ED90]) of DEX for continuous intraoperative infusion for EA prevention in children.

METHODS

We enrolled children aged 3 to 7 years who underwent dental treatment under sevoflurane anesthesia. DEX was continuously infused from the time of the establishment of the intravenous access until 5 minutes before the end of surgery. The initial DEX dose was 0.5 µg/kg/h, and subsequent dose adjustments were determined based on the response of the previous patient by using an up-down sequential allocation with a biased-coin design. The primary outcome was the ED90 for continuous DEX infusion based on the success or failure of the EA-preventing dose.

RESULTS

Forty-five patients were enrolled in the study. The DEX dose ranged from 0.50 to 0.90 µg/kg/h. The estimated ED90 (95% confidence interval [CI]) for preventing EA was 0.74 µg/kg/h (0.67-1.05 µg/kg/h). The duration of surgery (mean ± standard deviation [SD]) was 113 ± 30 minutes. The times (mean ± SD) for extubation, time to emergence, and recovery time were 5 ± 2 minutes, 27 ± 9 minutes, and 39 ± 7 minutes, respectively.

CONCLUSIONS

The ED90 for continuous intraoperative DEX infusion for EA prevention in pediatric patients receiving dental treatment under sevoflurane anesthesia was 0.74 µg/kg/h (95% CI, 0.67-1.05 µg/kg/h).

Effect of dexmedetomidine on preventing perioperative respiratory adverse events in children: A systematic review and meta‑analysis of randomized controlled trials

The most common critical incidents in pediatric anesthesia are perioperative respiratory adverse events (PRAEs). The present meta-analysis aimed to assess the preventive effect of dexmedetomidine on PRAEs in children. Dexmedetomidine is a highly selective α₂-adrenoceptor agonist that provides sedation, anxiolysis and analgesic effects without causing respiratory depression. Dexmedetomidine can diminish airway and circulatory responses during extubation in children. Original randomized controlled trial data were analyzed to study the putative effect of dexmedetomidine on PRAEs. By searched the Cochrane Library, EMBASE and PubMed, a total of ten randomized controlled trials (1,056 patients) was identified. PRAEs included cough, breath holding, laryngospasm, bronchospasm, desaturation (percutaneous oxygen saturation <95%), body movement and pulmonary rales. Compared with placebo, dexmedetomidine resulted in a significant reduction of incidence of cough, breath holding, laryngospasm and emergence agitation. The incidence of PRAEs was significantly reduced in dexmedetomidine compared with active comparators group. Moreover, dexmedetomidine decreased heart rate and increased post-anesthesia care unit stay duration by 11.18 min. The present analysis suggested that dexmedetomidine improved the airway function and decreased risks associated with general anesthesia in children. The present data demonstrated that dexmedetomidine may be a good choice to prevent PRAEs in children.

A comprehensive overview of clinical research on dexmedetomidine in the past 2 decades: A bibliometric analysis

Introduction: Dexmedetomidine is a potent, highly selective α-2 adrenoceptor agonist with sedative, analgesic, anxiolytic, and opioid-sparing properties. A large number of dexmedetomidine-related publications have sprung out in the last 2 decades. However, no bibliometric analysis for clinical research on dexmedetomidine has been published to analyze hot spots, trends, and frontiers in this field. Methods: The clinical articles and reviews related to dexmedetomidine, published from 2002 to 2021 in the Web of Science Core Collection, were retrieved on 19 May 2022, using relevant search terms. VOSviewer and CiteSpace were used to conduct this bibliometric study. Results: The results showed that a total of 2,299 publications were retrieved from 656 academic journals with 48,549 co-cited references by 2,335 institutions from 65 countries/regions. The United States had the most publications among all the countries (n = 870, 37.8%) and the Harvard University contributed the most among all institutions (n = 57, 2.48%). The most productive academic journal on dexmedetomidine was Pediatric Anesthesia and the first co-cited journal was Anesthesiology. Mika Scheinin is the most productive author and Pratik P Pandharipande is the most co-cited author. Co-cited reference analysis and keyword analysis illustrated hot spots in the dexmedetomidine field including pharmacokinetics and pharmacodynamics, intensive care unit sedation and outcome, pain management and nerve block, and premedication and use in children. The effect of dexmedetomidine sedation on the outcomes of critically ill patients, the analgesic effect of dexmedetomidine, and its organ protective property are the frontiers in future research. Conclusion: This bibliometric analysis provided us with concise information about the development trend and provided an important reference for researchers to guide future research.

Nurse-driven intranasal dexmedetomidine administration as sedation for non-invasive procedures in children: a single centre audit

The purpose of this study is to audit the efficacy and safety of intranasal dexmedetomidine sedation for non-invasive procedural sedation in children provided by nurses of the procedural sedation (PROSA) team in the University Hospitals Leuven. Efficacy (successful sedation as sole sedative) and safety (cardiorespiratory monitoring, saturation) were assessed. In this audit, prospectively recorded data were extracted from the medical files in 772 patients between 4 weeks to 18 years old, who underwent sedation with intranasal dexmedetomidine (2-4 µg/kg) by the nurse-driven PROSA team, following pre-screening on risk factors. Ninety-one percent of the patients were successfully sedated (single dose, monotherapy), 60 patients (7.8%) needed an additional intervention during sedation, 37 (4.8%) needed an extra dose of intranasal dexmedetomidine, and 14 (1.8%) received an additional other sedative. Successful sedation rates were higher in younger children, and medical imaging was the most common indication. Sedation failed in 12 (1.6%) patients, with 10 of them failed to fall asleep. Adverse events were limited in number (n = 13, 1.7%) and severity: 4 patients had a low heart rate (one received atropine), one had an irregular heart rate, and 7 desaturation events were described. Hypotension was treated with normal saline in one case.

CONCLUSIONS

In this nurse-driven PROSA setting, intranasal dexmedetomidine is effective and safe for non-invasive procedural sedation in an a priori low risk group of paediatric patients.

WHAT IS KNOWN

• Procedural sedation outside the operating theatre or intensive care units is increasingly used, including sedation performed by non-anaesthesiologists or nurses. This resulted in the development of procedural sedation and analgesia (PROSA) teams. • Off-label use of intranasal dexmedetomidine in children is increasing, with a limited number of audits on this practice, its safety and efficacy.

WHAT IS NEW

• In an audit on 772 procedures, nurse-driven intranasal dexmedetomidine administration as sedation for non-invasive procedures in children within a structured framework was safe and effective. • Imaging (CT, MRI) was the most common procedural indication in our study, but also nuclear imaging techniques were included.

Dexmedetomidine for sedation during hematopoietic stem cell harvest apheresis and leukapheresis in the PICU: Guideline development

BACKGROUND

Hematopoietic stem cell (HSC) harvest apheresis and leukapheresis are performed in the pediatric intensive care unit (PICU) for high-risk pediatric patients who require procedural sedation. Patients need central access either with their own central lines, ports or require apheresis catheter (CVL) placement. Previously, patients were either awake or emerging from sedation on PICU admission. Uncertainty regarding procedural sedation plans caused delays initiating sedation and apheresis. A guideline was developed to standardize Dexmedetomidine (DEX) for procedural sedation. We investigated if guideline implementation would improve efficiency during PICU admission as demonstrated by shorter time intervals for initiation of sedation, apheresis, PICU length of stay and less alternative sedating medication.

METHODS

Data was collected retrospectively from electronic health records of preguideline and post-guideline patients who were admitted to the PICU for sedated apheresis. We compared demographic and clinical characteristics, time intervals for sedation, apheresis, PICU length of stay, and sedation agents between the two groups using Fisher Exact tests and Mann-Whitney tests, as appropriate.

RESULTS

The groups did not differ in age or weight at the time of apheresis. All intervals of time compared were shorter post-guideline. Time intervals from admission to start of sedation, admission to start of apheresis, and admission to end of apheresis were statistically significantly different. The type and number of alternative sedating medications administered did not differ between the two groups.

CONCLUSION

This guideline implementation improved efficiency during PICU admission. This study might have been too small to demonstrate statistically significant differences in other time intervals studied.

Rapid emergence from dexmedetomidine sedation in Sprague Dawley rats by repurposing an α2-adrenergic receptor competitive antagonist in combination with caffeine

BACKGROUND

The α2 adrenergic receptor agonist dexmedetomidine is an important intravenous sedative with analgesic properties. Currently available dexmedetomidine reversal agents, like the α2-receptor antagonist atipamezole, cause serious adverse effects at the large dosages required for effective reversal; they are not used clinically. Without reversal agents, emergence times from dexmedetomidine sedation are slow. In this study we tested the ability of low-dose atipamezole, in combination with caffeine, to reverse dexmedetomidine sedation. The low dose of atipamezole employed should not be associated with unwanted effects.

METHODS

Two different sedation protocols were employed. In the first protocol, a bolus of dexmedetomidine was rapidly applied and the drug was allowed to equilibrate for 10 min before rats received either saline (as control) or low-dose atipamezole with caffeine. Following this procedure, rats were placed on their backs. Emergence from sedation was the time for rats to recover their righting reflex and stand with 4 paws on the floor. A second sedation protocol simulated a pediatric magnetic resonance imaging (MRI) scan. Adult rats were sedated with dexmedetomidine for one hour followed by 30 min with both dexmedetomidine and propofol. At the end of 90 min, rats received either saline (control) or a combination of low-dose atipamezole, and caffeine. Recovery of the righting reflex was used as a proxy for emergence from sedation.

RESULTS

Emergence from sedation, the time for rats to recover their righting reflex, decreased by ~ 90% when using an atipamezole dose ~ 20 fold lower than manufacturer's recommendation, supplemented with caffeine. Using an atipamezole dose ~ tenfold lower than recommended, with caffeine, emergence times decreased by ~ 97%. A different stimulant, forskolin, when tested, was as effective as caffeine. For the MRI simulation, emergence times were decreased by ~ 93% by low-dose atipamezole with caffeine.

CONCLUSIONS

Low dose atipamezole with caffeine was effective at reversing dexmedetomidine sedation. Emergence was rapid and the rats regained not only their righting reflex but also their balance and their ability to carry out complex behaviors. These findings suggest that the combination of low dose atipamezole with caffeine may permit rapid clinical reversal of dexmedetomidine without unwanted effects.

Nurse-led dexmedetomidine sedation for magnetic resonance imaging in children: a 6-year quality improvement project

We aimed to safely introduce dexmedetomidine into a nurse-led sedation service for magnetic resonance imaging in children. Secondary aims were to increase the number of children eligible for sedation and to increase the actual number of children having sedation performed by our nurse sedation team. We analysed 1768 consecutive intravenous and 219 intranasal dexmedetomidine sedation episodes in infants, children and adolescents having magnetic resonance imaging scans between March 2016 and March 2022. The overall sedation success rate was 98.4%, with a 98.9% success rate for intravenous dexmedetomidine and a 95.0% success rate for intranasal dexmedetomidine. The incidence of scan interruption during intravenous and intranasal dexmedetomidine sedation was 8.8% and 21.9%, respectively. We conclude that paediatric sedation with dexmedetomidine for magnetic resonance scanning is safe and successful.

Comparison of single-shot nebuliser protocol between dexmedetomidine and ketamine in children undergoing magnetic resonance imaging

BACKGROUND

Sedation for magnetic resonance imaging mandates deep sedation to ensure patient immobility. The nebulised route of drug delivery carries the advantage of good bioavailability and safety profile. We aimed to compare the efficacy and safety of nebulised dexmedetomidine and ketamine for sedation in children undergoing magnetic resonance imaging.

METHODS

A total of 71 children, aged two to eight years scheduled for outpatient magnetic resonance imaging were randomly allocated to receive nebulised dexmedetomidine 2 μg/kg (group D) or nebulised ketamine 2 mg/kg (group K) 30min before magnetic resonance imaging.

RESULTS

Nebulised dexmedetomidine (2 μg/kg) resulted in faster onset and significantly better sedation scores with rapid clear-headed recovery. Ketamine resulted in better venepuncture scores but was associated with more neuropsychological events at recovery.

CONCLUSION

Nebulised dexmedetomidine at 2 μg/kg provides rapid onset of satisfactory sedation, with good parental separation and a quicker and more clear-headed recovery, allowing for a smooth magnetic resonance imaging experience.

Dexmedetomidine decreases the 50% effective dose (ED50) of intravenous propofol required to prevent tracheal intubation response in Beagles

OBJECTIVE

To determine the 50% effective dose (ED50) of intravenous propofol required for successfully preventing tracheal intubation response in Beagles co-induced with dexmedetomidine.

ANIMALS

36 adult male Beagles.

PROCEDURES

The dogs were randomly assigned to either group D1, group D2, or group C (received 1 µg/kg, 2 µg/kg dexmedetomidine intravenously, or the same amount of normal saline as dexmedetomidine, 10 mL). The first dog in each group received 6 mg/kg of propofol for induction. The pump speed of propofol was 600 mL/h. The dosage varied with increments or decrements of 0.5 mg/kg based on the Dixon up-and-down method. The duration of eye-opening after propofol administration was recorded. Changes in heart rate (HR) and respiratory rate (RR) were recorded at 5 timepoints: after entering the operation room and prior to propofol administration (T1), 1 and 3 min after propofol administration (T2 and T3), 3 and 5 min after intubation (T4 and T5).

RESULTS

The required ED50 of propofol that prevented tracheal intubation response in D1, D2, and C groups were 6.4 mg/kg (95% CI, 6.1 to 6.7 mg/kg), 5.8 mg/kg (95% CI, 5.67 to 6 mg/kg), and 8.3 mg/kg (95% CI, 8 to 8.5 mg/kg), respectively. The recovery time of group D2 was significantly longer than that of groups D1 and C (P < .05). The differences in HR among the 3 groups were significant from T2 up to T5 timepoint (P < .05). The differences in RR among the 3 groups were significant at T2 and T3 timepoints (P < .05).

CLINICAL RELEVANCE

Dexmedetomidine pre-injection reduces the amount of propofol required for endotracheal intubation response in Beagles, thereby reducing the respiratory inhibition induced by propofol.

The comparison of ketamine-dexmedetomidine (ketadex) and ketamine-propofol (ketofol) for procedural sedation in pediatric patients: A meta-analysis of randomized controlled trials

Introduction

The combination of different agents used for procedural sedation allows a greater range of desirable effects while minimizing side effects. The ketamine-dexmedetomidine combination (ketadex) and ketamine-propofol combination (ketofol) are successful examples. The purpose of this meta-analysis was to compare the safety and efficacy of ketadex with ketofol used for procedural sedation in pediatric patients.

Methods

We searched Pubmed, Cochrane Controlled Register of Trials, and Embase from inception to June 2022. Studies were independently evaluated for inclusion criteria and exclusion criteria by two reviewers. Outcome measures for safety comparison were the incidence of hypotension, bradycardia, respiratory depression, nausea, vomiting, and agitation; Outcome measure for efficacy comparison was clinicians' satisfaction. In addition, we compared the recovery time of ketadex and ketofol.

Results

Nine studies were included in this meta-analysis. Compared with ketofol, ketadex sedation in pediatric patients had lower risk of respiratory depression (RR: 0.51, 95% CI: 0.34–0.76, P = 0.0009). However, ketadex displayed significant effect on recovery time (MD: 8.38 min, 95% CI: 7.55–9.22 min, P < 0.00001). Ketadex had similar incidence of hypotension (RR: 0.95, 95% CI: 0.33–2.67, P = 0.92) and bradycardia (RR: 1.80, 95% CI: 0.64–5.06, P = 0.26) compared to those with ketofol. Clinicians' satisfaction rate of ketadex and ketofol were both high (RR: 0.93, 95% CI: 0.69–1.25, P = 0.62). Also, no significant difference was observed between ketadex and ketofol on the incidence of nausea, vomiting, and agitation.

Conclusions

Both ketadex and ketofol can provide effective sedation and maintain stable hemodynamics. In consideration of good safety profile in respiratory problems, we suggest ketadex is a better option for procedural sedation in pediatric patients.

Dexmedetomidine and perioperative analgesia in children

Dexmedetomidine (DEX) is an anaesthetic agent that mimics natural deep sleep and produces minimal cardiorespiratory depression. As such, it is a very valuable option in the management of such a challenging population as paediatric patients. The main objective of this mini review was to evaluate the role of DEX as a perioperative analgesic in children receiving anaesthesia. We searched Google, Pubmed, Embase and the Cochrane Library for articles published between 2010 and 2021, and reviewed various of aspects of DEX, such as pharmacology, effectiveness, safety, and the most recent evidence on its clinical use as an analgesic in paediatric anaesthesia. We also include a cost estimate of perioperative analgesia with DEX.

Improved postoperative recovery profile in pediatric oral rehabilitation with low-dose dexmedetomidine as an opioid substitute for general anesthesia: a randomized double-blind clinical trial

Background

Low-dose dexmedetomidine may be a suitable alternative to opioids for pediatric ambulatory procedures under general anesthesia (GA). However, the recovery profile remains unclear. Herein, we aimed to evaluate the effects of low-dose dexmedetomidine on the recovery profile of children.

Methods

Seventy-two children undergoing ambulatory oral rehabilitation under GA were randomly and equally distributed into two groups (D and F). Group D received an infusion of dexmedetomidine 0.25 µg/kg for 4 min for induction, followed by maintenance of 0.4 µg/kg/h. Group F received an infusion of fentanyl 1 µg/kg over 4 min for induction, followed by maintenance at 1 µg/kg/h. The primary outcome was the extubation time. The secondary outcomes were awakening time, end-tidal sevoflurane (ET-Sevo) requirement, change in hemodynamic parameters, Richmond Agitation-Sedation Scale (RASS), Children's Hospital of Eastern Ontario pain scale (CHEOPS) score, length of PACU stay, and incidence of adverse events.

Results

Statistically significant differences were observed in the recovery profile between the groups: the median time for extubation was 3.65 (3.44-6.2) vs. 6.25 (4.21-7) minutes in groups D vs. F (P = 0.001), respectively, while the corresponding awakening times were 19 (18.75-21) and 22.5 (22-24) minutes, respectively (P < 0.001). The mean ET-Sevo was low in group D (1.1 vs. 1.2; P < 0.001). The heart rate was significantly low across all time points in group D, without resulting in bradycardia. The median RASS and CHEOPS scores were also significantly lower in group D. No significant differences were observed in the mean arterial pressure, incidence of adverse events, or length of PACU stay.

Conclusion

Low-dose dexmedetomidine was more effective than fentanyl as an opioid substitute at providing a better recovery profile in pediatric ambulatory oral rehabilitation under GA. Dexmedetomidine also significantly reduced sevoflurane consumption without causing adverse events or prolonging hospital stay.

Intranasal Dexmedetomidine as Sedative for Medical Imaging in Young Children: A Systematic Review to Provide a Roadmap for an Evidence-Guided Clinical Protocol

There is an increasing need for effective anxiety and pain reduction during medical imaging procedures in children, addressed by non-pharmacological or pharmacological approaches. Dexmedetomidine is a fairly recently marketed, selective α2-adrenergic agonist that can be administered intranasally. To develop an evidence-guided clinical protocol, we investigated the (side) effects, preconditions and safety aspects following intranasal dexmedetomidine administration in children (1 month–5 years) for procedural sedation during medical imaging. To this end, a systematic search (PubMed, Embase and CINAHL (12/2021)) was performed to identify studies on intranasal dexmedetomidine for procedural sedation for medical imaging (computer tomography and magnetic resonance imaging). Following screening and quality assessment, eight studies were retained. Nasal nebulization was considered the best administration method, dosing varied between 2 and 4 µg/kg (age-dependent) 30–45 min prior to imaging and contraindications or restrictions with respect to oral intake were somewhat consistent across studies. Valid sedation scores and monitoring of vital signs were routinely used to assess sedation and the need for rescue dosing (different approaches), whereas discharge was generally based on Aldrete score (score ≥ 9). Heart rate, blood pressure and saturation were routinely monitored, with commonly observed bradycardia or hypotension (decrease by 20%). Based on these findings, a roadmap for evidence-guided clinical protocol was generated.

Dex modulates the balance of water-electrolyte metabolism by depressing the expression of AVP in PVN

Dexmedetomidine (Dex) is a highly selective α2 adrenergic agonist used in clinical anesthesia. Studies have shown that Dex can act on the collecting duct and reduce the body’s water reabsorption, thereby increasing water discharge. However, the specific mechanism of Dex on water homeostasis remains unclear. The hypothalamus is the regulatory center of water and salt balance and secretes related neurochemical hormones, such as arginine vasopressin (AVP), to regulate the discharge of water and salt. The paraventricular nucleus (PVN) and supraoptic nucleus (SON) in the hypothalamus are also considered to be the key targets of the thirst loop. They are responsible for the secretion of AVP. The suprachiasmatic nucleus (SCN) is also one of the brain regions where AVP neurons are densely distributed in the hypothalamus. This study used C57BL/6J mice for behavior, immunofluorescence, and blood analysis experiments. Our results showed that Dex could not only depress the expression of AVP in the PVN but also reduce serum AVP concentration. The animal water intake was decreased without impairing the difference in food consumption and the urine excretion was enhanced after the intraperitoneal injection of Dex, while AVP supplementation restored the water intake and inhibited the urine excretion of mice in the Dex group. In addition, the renin-angiotensin-aldosterone system is vital to maintaining serum sodium concentration and extracellular volume. We found that serum sodium, serum chloride, serum aldosterone (ALD) concentration, and plasma osmolality were decreased in the Dex group, which inhibited water reabsorption, and the plasma osmolarity of mice in the Dex group supplemented with AVP was significantly higher than that in Dex group. We also found that Dex significantly increased the concentration of blood urea nitrogen and decreased the concentration of creatinine within the normal range of clinical indicators, indicating that there was no substantive lesion in the renal parenchyma. These results showed that Dex could modulate the balance of water-electrolyte metabolism by depressing the expression of AVP in PVN without impairing renal function.

Dexmededomidine in pediatric unilateral internal inguinal ring ligation

BACKGROUND

Safe and effective analgesia strategy remains one of the priorities for pediatric inguinal hernia treatment.

AIM

To explore safety and efficacy of dexmededomidine monotherapy for postoperative analgesia in children who received laparoscopic unilateral internal inguinal ring ligation.

METHODS

This randomized single-center controlled trial included 390 children (aged 1-3 years, ASA grade I-II), randomly divided into a dexmededomidine group (D group), a dexmededomidine + sufentanil group (DS group), and a sufentanil group (S group). The primary endpoint was percentage of children with the Face, Legs, Activity, Cry, and Consolability (FLACC) score ≤ 3 points 2 h after surgery.

RESULTS

The comparisons of the FLACC scores at 2, 4, 6, 8, 12, and 24 h were not significantly different among the three groups (P > 0.05). The sedative effects in the D group were significantly better than those in the S group (P > 0.05), but not significantly different from those in the DS group. The incidence of nausea and vomiting was significantly lower in the D group than in the S group and DS group (P > 0.05).

CONCLUSION

Analgesic effects of dexmededomidine monotherapy are comparable to those of sufentanil alone or in combination with dexmededomidine for children who underwent laparoscopic unilateral internal inguinal ring ligation, with better sedative effects and a lower incidence of adverse events.

CYP2A6 and GABRA2 Gene Polymorphisms are Associated With Dexmedetomidine Drug Response

Background: Dexmedetomidine is a commonly used clinical sedative; however, the drug response varies among individuals. Thus, the purpose of this study was to explore the association between dexmedetomidine response and gene polymorphisms related to drug-metabolizing enzymes and drug response (CYP2A6, UGT2B10, UGT1A4, ADRA2A, ADRA2B, ADRA2C, GABRA1, GABRB2, and GLRA1).

Methods: This study was a prospective cohort study. A total of 194 female patients aged 18–60 years, American Society of Anesthesiologists (ASA) score I-II, who underwent laparoscopy at the Third Xiangya Hospital of Central South University, were included. The sedative effect was assessed every 2 min using the Ramsay score, and the patient’s heart rate decrease within 20 min was recorded. Peripheral blood was collected from each participant to identify genetic variants in the candidate genes of metabolic and drug effects using the Sequenom MassARRAY^® platform. Furthermore, additional peripheral blood samples were collected from the first 99 participants at multiple time points after dexmedetomidine infusion to perform dexmedetomidine pharmacokinetic analysis by Phoenix^® WinNonlin 7.0 software.

Results: Carriers of the minor allele (C) of CYP2A6 rs28399433 had lower metabolic enzyme efficiency and higher plasma concentrations of dexmedetomidine. In addition, the participants were divided into dexmedetomidine sensitive or dexmedetomidine tolerant groups based on whether they had a Ramsay score of at least four within 20 min, and CYP2A6 rs28399433 was identified to have a significant influence on the dexmedetomidine sedation sensitivity by logistic regression with Plink software [p = 0.003, OR (95% CI): 0.27 (0.11–0.65)]. C allele carriers were more sensitive to the sedative effects of dexmedetomidine than A allele carriers. GABRA2 rs279847 polymorphism was significantly associated with the degree of the heart rate decrease. In particular, individuals with the GG genotype had a 4-fold higher risk of heart rate abnormality than carriers of the T allele (OR = 4.32, 95% CI: 1.96–9.50, p = 0.00027).

Conclusion:CYP2A6 rs28399433 polymorphism affects the metabolic rate of dexmedetomidine and is associated with susceptibility to the sedative effects of dexmedetomidine; GABRA2 rs279847 polymorphism is significantly associated with the degree of the heart rate decrease.

Analgesia, Sedation, Paralytics, Delirium, and Iatrogenic Withdrawal

The care of the critically ill child often includes medications used for the relief of pain and anxiety. Children have key differences in pharmacokinetics and pharmacodynamics compared with adults that should always be considered to achieve safe medication use in this population. Pain must be addressed, and sedative use should be minimized when possible. Our understanding of sedation safety is evolving, and studies have shown that minimizing exposure to multiple medications can reduce the burden of delirium and iatrogenic withdrawal.

Evaluation of Nebulised Dexmedetomidine Given Pre-operatively to Attenuate Hemodynamic Response to Laryngoscopy and Endotracheal Intubation: A Randomised Control Trial

Background and aim

A variety of medications have been studied to reduce the hemodynamic response to laryngoscopy and intubation. Dexmedetomidine has been used intravenously in many studies to reduce the hemodynamic response to laryngoscopy and intubation. In high-risk patients, this pressor response can increase morbidity and mortality. As dexmedetomidine has a good bioavailability via the nebulisation route, we formulated this study to evaluate the effect of nebulised dexmedetomidine on the hemodynamic response to laryngoscopy and endotracheal intubation.

Methods

This is a prospective, randomised controlled trial conducted on 100 patients with the American Society of Anesthesiologists grade I and II. The primary objective of the study was to see if nebulised dexmedetomidine at a dose of 1 microgram/kg could reduce the stress reaction to laryngoscopy and intubation. The secondary objective was to study the dose sparing effect of nebulised dexmedetomidine on the amount of propofol used during induction of general anaesthesia. The study population was randomly divided into two groups: group A (n = 50) included patients nebulised with dexmedetomidine 1 microgram/kg and group B (n = 50) included patients nebulised with 5 ml saline 30 minutes before induction of anaesthesia in a sitting position.

Results

The demographics were similar in both groups. Following laryngoscopy and intubation, the systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and heart rate showed a significant increase in the control group B as compared to the treatment group A. In group A, there was attenuation in SBP (one minute = 113.2 ± 14.503, P < 0.001; five minutes = 109.86 ± 8.342, P < 0.001; 10 minutes = 114.24 ± 7.797, P = 0.010), DBP (one minute = 73.72 ± 10.986, P = 0.011; five minutes = 71.62 ± 9.934, P = 0.005; 10 minutes = 76.1 ± 8.006, P = 0.009), MAP (one minute = 86.80 ± 11.86, P = 0.001; five minutes = 84.44 ± 8.97, P = 0.006; 10 minutes = 88.72 ± 7.44, P = 0.018), and heart rate (one minute = 83.34 ± 12.325, P = 0.001; five minutes = 81.56 ± 13.33, P = 0.003; 10 minutes = 80.16 ± 14.086, P = 0.013) following laryngoscopy and intubation. Induction dose of propofol was significantly lower in the dexmedetomidine group (73 ± 19.509, P < 0.001).

Conclusion

Nebulised dexmedetomidine effectively blunts the hemodynamic response to laryngoscopy and intubation and also has a dose sparing effect on the induction dose of propofol.

Protective effects of dexmedetomidine in vital organ injury: crucial roles of autophagy

Vital organ injury is one of the leading causes of global deaths. Accumulating studies have demonstrated that dexmedetomidine (DEX) has an outstanding protective effect on multiple organs for its antiinflammatory and antiapoptotic properties, while the underlying molecular mechanism is not clearly understood. Autophagy, an adaptive catabolic process, has been found to play a crucial role in the organ-protective effects of DEX. Herein, we present a first attempt to summarize all the evidence on the proposed roles of autophagy in the action of DEX protecting against vital organ injuries via a comprehensive review. We found that most of the relevant studies (17/24, 71%) demonstrated that the modulation of autophagy was inhibited under the treatment of DEX on vital organ injuries (e.g. brain, heart, kidney, and lung), but several studies suggested that the level of autophagy was dramatically increased after administration of DEX. Albeit not fully elucidated, the underlying mechanisms governing the roles of autophagy involve the antiapoptotic properties, inhibiting inflammatory response, removing damaged mitochondria, and reducing oxidative stress, which might be facilitated by the interaction with multiple associated genes (i.e., hypoxia inducible factor-1α, p62, caspase-3, heat shock 70 kDa protein, and microRNAs) and signaling cascades (i.e., mammalian target of rapamycin, nuclear factor-kappa B, and c-Jun N-terminal kinases pathway). The authors conclude that DEX hints at a promising strategy in the management of vital organ injuries, while autophagy is crucially involved in the protective effect of DEX.

Intranasal versus sublingual route of dexmedetomidine sedation in paediatric dentistry: A randomized controlled clinical trial

BACKGROUND

Many children experience dental anxiety during dental treatment. Conscious sedation is used to alleviate anxiety and enhance a child's cooperation.

AIM

This study aimed to compare the efficacy of intranasal versus sublingual dexmedetomidine.

DESIGN

Forty-two healthy, uncooperative children participated in the study. They were divided randomly into two groups: In the first visit, Group I received intranasal dexmedetomidine and group II received sublingual dexmedetomidine, whereas at the second visit, the alternate route was implemented in a crossover design. The child's acceptance of drug administration method was assessed using a 4-point rating scale. Time until optimum sedation was measured. Anxiety during local anesthesia administration was scored using Venham's rating scale. Postoperative response was recorded through Vernon et al's questionnaire.

RESULTS

The sublingual dexmedetomidine route was better accepted than the intranasal route (P=0.01), while the latter acted faster (P>0.001). No significant difference in anxiety scores was found between groups at baseline (P=0.84) or during local anesthetic administration (P=0.44). No negative effect was recorded by the parents who answered the Modified Vernon et al questionnaire 24 hour after the dental visit compared to before the dental visit (P=1.00).

CONCLUSIONS

Both routes prevented the increase in anxiety scores equally during local anesthesia and do not have negative effect on postoperative behavior of children. However, the sublingual route showed better acceptance with longer onset time of action than the intranasal route.

Recent Advances in the Clinical Value and Potential of Dexmedetomidine

Dexmedetomidine, a highly selective α2-adrenoceptor agonist, has sedative, anxiolytic, analgesic, sympatholytic, and opioid-sparing properties and induces a unique sedative response which shows an easy transition from sleep to wakefulness, thus allowing a patient to be cooperative and communicative when stimulated. Recent studies indicate several emerging clinical applications via different routes. We review recent data on dexmedetomidine studies, particularly exploring the varying routes of administration, experimental implications, clinical effects, and comparative advantages over other drugs. A search was conducted on the PubMed and Web of Science libraries for recent studies using different combinations of the words “dexmedetomidine”, “route of administration”, and pharmacological effect. The current routes, pharmacological effects, and application categories of dexmedetomidine are presented. It functions by stimulating pre- and post-synaptic α2-adrenoreceptors within the central nervous system, leading to hyperpolarization of noradrenergic neurons, induction of an inhibitory feedback loop, and reduction of norepinephrine secretion, causing a sympatholytic effect, in addition to its anti-inflammation, sleep induction, bowel recovery, and sore throat reduction effects. Compared with similar α2-adrenoceptor agonists, dexmedetomidine has both pharmacodynamics advantage of a significantly greater α2:α1-adrenoceptor affinity ratio and a pharmacokinetic advantage of having a significantly shorter elimination half-life. In its clinical application, dexmedetomidine has been reported to present a significant number of benefits including safe sedation for various surgical interventions, improvement of intraoperative and postoperative analgesia, sedation for compromised airways without respiratory depression, nephroprotection and stability of hypotensive hemodynamics, reduction of postoperative nausea and vomiting and postoperative shivering incidence, and decrease of intraoperative blood loss. Although the clinical application of dexmedetomidine is promising, it is still limited and further research is required to enhance understanding of its pharmacological properties, patient selection, dosage, and adverse effects.

Administration of Intravenous Dexmedetomidine and Acetaminophen for Improved Postoperative Pain Management in Primary Palatoplasty

OBJECTIVE

Suboptimal pain management after primary palatoplasty (PP) may lead to complications such as hypoxemia, and increased hospital length of stay. Opioids are the first option for postoperative acute pain control after PP; however, adverse effects include excessive sedation, respiratory depression, and death, among others. Thus, optimizing postoperative pain control using opioid-sparing techniques is critically important. This paper aims to analyze efficacy and safety of combined intravenous (IV), dexmedetomidine, and IV acetaminophen during PP.

METHODS

Review of a cohort of patients who underwent PP from April 2009 to July 2018 at a large free-standing children's hospital was performed, comparing patients who received combined IV dexmedetomidine and acetaminophen with those who did not receive either of the 2 medications. Efficacy was measured through opioid and nonopioid analgesic dose and timing, pain scores, duration to oral intake, and length of stay. Safety was measured by 30-day complication rates including readmission for bleeding and need for supplementary oxygen.

RESULTS

Total postoperative acetaminophen (P = 0.01) and recovery room fentanyl (P < 0.001) requirements were significantly lower in the study group compared with the control group. Length of stay, oral intake duration, pain scores, total postoperative opioid requirements, and complications rates trended favorably in the study group, though differences did not reach statistical significance.

CONCLUSIONS

Intraoperative IV dexmedetomidine and acetaminophen during PP provides safe and effective perioperative pain control, resulting in statistically significant decreased need for postoperative acetaminophen and fentanyl. Larger studies are necessary to determine if other trends identified in this study may be significant.

Association of dexmedetomidine with recovery room and hospital discharge times: A retrospective cohort analysis

BACKGROUND

Dexmedetomidine is a useful anesthetic adjunct, increasingly popular during pediatric surgery and procedural sedation. Its half-life of 2-3 hours might prolong recovery and discharge times when compared with an un-supplemented propofol anesthetic. This may create an additional burden in a busy post-anesthetic care unit (PACU).

AIM

To investigate whether intraoperative adjuvant dexmedetomidine delays PACU discharge in patients undergoing propofol anesthesia for day surgery or procedural investigations with minimal anticipated post-procedural pain.

METHODS

We conducted a retrospective review of outpatient procedures performed during a six-month period including pediatric patients, ASA physical status I-III, who underwent intravenous anesthesia with propofol and remifentanil for magnetic resonance imaging (MRI), strabismus repair, upper gastrointestinal endoscopy, or combined upper/lower gastrointestinal endoscopy. Patients receiving a sedative premedication, long-acting opioids, or volatile anesthetics for maintenance of anesthesia, were excluded. Duration of PACU stay was compared for patients who did or did not receive intraoperative dexmedetomidine in the four procedure groups.

RESULTS

Charts were reviewed for 359 patients; 130 (36%) received dexmedetomidine. Median differences in duration of PACU stay for dexmedetomidine versus non-dexmedetomidine cases were: 5 minutes (95%CI 0 to 10, p=0.037) for MRI; 5 minutes (95%CI -3 to 15, p=0.258) for strabismus surgery; 7 minutes (95%CI 3 to 10, p<0.001) for upper endoscopy; and 5 minutes (95%CI 1 to 12, p=0.021) for combined upper/lower endoscopy. Linear regression (F=61.1, adjusted R² =0.40) indicated a significant relationship between dexmedetomidine dose (estimate 14.6 minutes per μg/kg, 95%CI 8.2 to 21.1, p<0.001) and duration of PACU stay.

CONCLUSION

We found evidence for a small association of intraoperative dexmedetomidine with duration of recovery from propofol anesthesia for a set of common outpatient procedures, with a potential dose relationship equivalent to approximately 15 minutes delay per μg/kg dexmedetomidine administered. Future research into the benefits of dexmedetomidine in pediatric anesthesia should further evaluate this relationship.

The frequency of emergence delirium in children undergoing outpatient anaesthesia for magnetic resonance imaging

AIM

The aim of this study was to investigate the effect on the occurrence of emergence delirium of propofol and ketofol with intranasal dexmedetomidine and midazolam applied as premedication to paediatric patients during magnetic resonance imaging (MRI).

METHODS

The study included children aged 2-10 years who received sedation for MRI, separated into four groups. Group MP (midazolam-propofol) received intranasal midazolam (0.2 mg/kg) for premedication and intravenous (IV) propofol (1 mg/kg) as the anaesthetic agent. Group MK (midazolam-ketofol) received intranasal midazolam (0.2 mg/kg) for premedication and IV ketofol (1 mg/kg) as the anaesthetic agent. Group DP (dexmedetomidine-propofol) received intranasal dexmedetomidine (1 mcg/kg) for premedication and IV propofol (1 mg/kg) as the anaesthetic agent. Group DK (dexmedetomidine-ketofol) received intranasal dexmedetomidine (1 mcg/kg) for premedication and IV ketofol (1 mg/kg) as the anaesthetic agent. The Paediatric Anaesthesia Emergence Delirium (PAED) scale was used to evaluate delirium. A PAED score ≥ 10 was accepted as delirium.

RESULTS

Statistical analysis was made of 140 paediatric patients. Delirium developed in 1.42% of all the patients, and in 5.7% of Group MP. The mean Aldrete and PAED scores were lower and the length of stay in the recovery room was shorter in Group DP than in the other groups. The need for additional anaesthetic was highest in Group DP at 94.3% and lowest in Group DK at 14.3%. The groups administered ketofol were observed to have a lower requirement for additional anaesthetic.

CONCLUSION

Delirium was seen at a very low rate only in the Group MP and it is difficult to say the best combination in terms of delirium frequency. However, intranasal dexmedetomidine and IV ketofol seem to be better and safer than the other groups in terms of the need for additional doses and the number of side effects. The addition of ketamine to propofol reduces the need for additional doses with a synergistic effect.

Dexmedetomidine does not compromise neuronal viability, synaptic connectivity, learning and memory in a rodent model

Recent animal studies have drawn concerns regarding most commonly used anesthetics and their long-term cytotoxic effects, specifically on the nervous tissue. It is therefore imperative that the search continues for agents that are non-toxic at both the cellular and behavioural level. One such agent appears to be dexmedetomidine (DEX) which has not only been found to be less neurotoxic but has also been shown to protect neurons from cytotoxicity induced by other anesthetic agents. However, DEX's effects on the growth and synaptic connectivity at the individual neuronal level, and the underlying mechanisms have not yet been fully resolved. Here, we tested DEX for its impact on neuronal growth, synapse formation (in vitro) and learning and memory in a rodent model. Rat cortical neurons were exposed to a range of clinically relevant DEX concentrations (0.05-10 µM) and cellular viability, neurite outgrowth, synaptic assembly and mitochondrial morphology were assessed. We discovered that DEX did not affect neuronal viability when used below 10 µM, whereas significant cell death was noted at higher concentrations. Interestingly, in the presence of DEX, neurons exhibited more neurite branching, albeit with no differences in corresponding synaptic puncta formation. When rat pups were injected subcutaneously with DEX 25 µg/kg on postnatal day 7 and again on postnatal day 8, we discovered that this agent did not affect hippocampal-dependent memory in freely behaving animals. Our data demonstrates, for the first time, the non-neurotoxic nature of DEX both in vitro and in vivo in an animal model providing support for its utility as a safer anesthetic agent. Moreover, this study provides the first direct evidence that although DEX is growth permissive, causes mitochondrial fusion and reduces oxygen reactive species production, it does not affect the total number of synaptic connections between the cortical neurons in vitro.

Sequestration of Dexmedetomidine in Ex Vivo Cardiopulmonary Bypass Circuits

Dexmedetomidine (DEX) is a sedative used in combination with other drugs in neonates and infants undergoing cardiac surgery using cardiopulmonary bypass (CPB). This study aimed to evaluate the disposition of DEX after administration to the ex vivo CPB circuits following different bolus doses and continuous infusion of DEX, including the effect of circuit coating, temperature, and modified ultrafiltration (MUF). Cardiopulmonary bypass circuits were setup ex vivo and primed with reconstituted blood. Dexmedetomidine was administered to the circuit (as a single bolus or single bolus along with continuous infusion). The circuit was allowed to equilibrate during the first 5 minutes, blood samples were collected at multiple time points (5-240 minutes). Blood samples were processed to collect plasma and analyzed for DEX with a validated assay. The majority of DEX sequestration in ex vivo CPB circuits occurred within the first 15 minutes. The percent of DEX remained in plasma pre-MUF (16-71%) and post-MUF (22-92%) varied depending on the dose and dosing scheme. Modified ultrafiltration significantly increased the plasma concentration of DEX in 19 of 23 circuits by an average of 12.1 ± 4.25% (p < 0.05). The percent sequestration of DEX was lower in CPB circuits at lower DEX doses compared to higher doses. A combination of DEX initial loading dose and continuous infusion resulted in steady concentrations of DEX over 4 hours. At therapeutically relevant concentrations of DEX (485-1,013 pg/ml), lower sequestration was observed in ex vivo CPB circuits compared to higher doses. The sequestration of DEX to circuits should be considered to achieve the optimal concentration of DEX during CPB surgery.

Dexmedetomidine leading to profound bradycardia in a pediatric liver transplant recipient

Dexmedetomidine, an α₂ -agonist, is used in the PICU for its sedative properties as it minimally affects respiratory status. However, hemodynamic instability is one of its known side effects. There is limited published experience with its use in pediatric liver transplant. We present a case of a 9-month-old infant who received a deceased donor liver transplantation for biliary atresia and received an IV dexmedetomidine infusion for sedation starting at 20 hours post-operatively. The patient received an IV bolus of 0.08 mcg/kg followed by an increase to 1 mcg/kg/hour. She was also receiving a fentanyl infusion for sedation at the time of dexmedetomidine initiation. Approximately 3 hours after initiation, she developed bradycardia as low as 30 beats-per-minute with an associated sinus pause of 7 seconds. She was given chest compressions by the bedside nurse briefly before arousing and becoming agitated. Evaluation of other etiologies for the patient's bradycardia was unrevealing. Thus, bradycardia was attributed to dexmedetomidine therapy which was discontinued without recurrence. Hemodynamic instability, specifically bradycardia, is known to occur with dexmedetomidine administration. As this medication is primarily metabolized by the liver, its use immediately after transplantation, when liver function is still recovering, may be associated with an increased risk of side effects. Understanding risk factors for bradycardia and hemodynamic instability early after liver transplantation, particularly with dexmedetomidine, is critical to allow clinicians to identify the patients for higher risk for dexmedetomidine side effects.

Circulating microRNA-30a-5p, microRNA-101-3p, microRNA-140-3p and microRNA-141-3p as potential biomarkers for dexmedetomidine response in pediatric patients

PURPOSE

The aim of this study was to investigate the expression levels of plasma miR-30a-5p, miR-101-3p, miR-140-3p and miR-141-3p and their relationship to dexmedetomidine efficacy and adverse effects in pediatric patients.

METHODS

The expression levels of miR-30a-5p, miR-101-3p, miR-140-3p and miR-141-3p were measured by qRT-PCR in plasma of 133 pediatric patients receiving dexmedetomidine for preoperative sedation. We analyzed the relationship between miRNA abundance and dexmedetomidine response, including sedative effect and adverse effects, and assessed the predictive power of miRNAs for drug response.

RESULTS

Among 133 pediatric patients, 111 patients were dexmedetomidine responders (UMSS ≥ 2) and 22 patients were non-responders (UMSS < 2). We observed higher expression levels of miR-101-3p and miR-140-3p in dexmedetomidine responders compared with non-responders (P < 0.05, P < 0.0001). In contrast, there was no significant difference in the expression levels of miR-30a-5p and miR-141-3p between responders and non-responders (P > 0.05). The plasma levels of miR-101-3p and miR-30a-5p were markedly downregulated in patients who experienced hypotension and bradycardia, respectively (P < 0.05). MiR-101-3p and miR-140-3p demonstrated a potential discriminatory ability between dexmedetomidine responders and non-responders, with AUC of 0.64 (P < 0.05) and 0.77 (P < 0.0001), respectively. The AUC of miR-101-3p in distinguishing patients without hypotension was 0.63 (P < 0.05). The AUC of miR-30a-5p in distinguishing patients without bradycardia was 0.74 (P < 0.05).

CONCLUSION

Our study demonstrated that circulating miR-101-3p, miR-140-3p and miR-30a-5p might be used as a blood-based marker for dexmedetomidine efficacy and safety in pediatric patients.

Effects of opioid-reduced anesthesia during scoliosis surgery in children: a prospective observational study

Aims: Opioid-reduced anesthesia (ORA) was suggested to decrease morphine consumption after adolescent idiopathic scoliosis (AIS) surgery and incidence of chronic pain. Materials & methods: A prospective analysis using the ORA in AIS surgery was performed. Two cohorts were compared: a control group (opioid-based anesthesia) and the ORA group. The main outcome was morphine consumption at day 1. Results: 33 patients operated for AIS using ORA were compared with 36 with opioid-based anesthesia. Morphine consumption was decreased in the ORA group (1.1 mg.kg^-1 [0.2-2] vs 0.8 mg.kg^-1 [0.3-2]; p = 0.02) at day 1. Persistent neuropathic pain at 1 year was decreased in the ORA group (p = 0.02). Conclusion: The ORA protocol is efficient to reduce postoperative morphine consumption in AIS surgery and preventing neuropathic pain.

Dexmedetomidine & perioperative analgesia in children

Dexmedetomidine (DEX) is an anaesthetic agent that mimics natural deep sleep and produces minimal cardiorespiratory depression. As such, it is a very valuable option in the management of such a challenging population as paediatric patients. The main objective of this mini review was to evaluate the role of DEX as a perioperative analgesic in children receiving anaesthesia. We searched Google, Pubmed, Embase and the Cochrane Library for articles published between 2010 and 2021, and reviewed various of aspects of DEX, such as pharmacology, effectiveness, safety, and the most recent evidence on its clinical use as an analgesic in paediatric anaesthesia. We also include a cost estimate of perioperative analgesia with DEX.

Effectiveness of nebulized dexmedetomidine for treatment of post-dural puncture headache in parturients undergoing elective cesarean section under spinal anesthesia: a randomized controlled study

PURPOSE

The need for effective treatment for post-dural puncture headache (PDPH) is a growing research entity. This study aimed to test the effectiveness of additional dexmedetomidine (DEX) to PDPH conservative management and evaluate its cerebral hemodynamic effects trans-cranial Doppler.

METHODS

This prospective randomized double-blind controlled trial was conducted on 43 post-partum females suffering from PDPH with visual analog score (VAS) ≥ 4 and Lybecker score ≥ 2. The study subjects were allocated into control group [n = 22] received nebulization of 4 mL 0.9% saline and DEX group [n = 21] received nebulization of 1 µg/kg DEX diluted in 4 mL 0.9% saline twice daily that was continued until achieving VAS score ≤ 3 and Lybecker score < 2 and/or for a maximum of 72 h. Both groups received routine conservative management. The primary outcome was the VAS and Lybecker scores and the secondary results were the DEX effects on cerebral vessels and the occurrence of any adverse effects.

RESULTS

VAS and Lybecker scores were significantly lower in DEX group. The middle cerebral artery mean flow velocity was significantly lower, and the pulsatility index was considerably higher after DEX nebulization compared to placebo. Two patients in the control group were indicated for epidural blood patch.

CONCLUSION

The addition of DEX nebulization (1 µg/kg twice daily) to the PDPH conservative care effectively relieved the symptoms and lowered pain scores which could be due to its analgesic and cerebral vasoconstrictive effects.

TRIAL REGISTRATION

This study was approved by the research ethical committee of Faculty of Medicine, Zagazig University with the reference number (ZU-IRB#: 6075/26-4-2020) and it was registered under clinicaltrials.gov (NCT04327726).

Safety and Efficacy of Single-Dose Ketorolac for Postoperative Pain Management After Primary Palatoplasty: A Prospective Cohort Study With Historical Controls

OBJECTIVE

To analyze safety and efficacy of single-dose ketorolac after primary palatoplasty (PP).

DESIGN

Consecutive cohort of patients undergoing PP, comparing to historical controls. Setting: A large academic children's hospital.

PATIENTS, PARTICIPANTS

A consecutive cohort of 111 patients undergoing PP (study n = 47) compared to historical controls (n = 64).

INTERVENTIONS

All patients received intraoperative acetaminophen, dexmedetomidine, and opioids while the study group received an additional single dose of ketorolac (0.5 mg/kg) at the conclusion of PP.

MAIN OUTCOME MEASURES

Safety of ketorolac was measured by significant bleeding complications and need for supplementary oxygen. Efficacy was assessed through bleeding, Face Legs Activity Cry Consolability (FLACC) scale, and opioid dose.

RESULTS

Length of stay was similar for both groups (control group 38.5 hours [95% CI: 3.6-43.3] versus study group 37.6 hours [95% CI: 31.3-44.0], P = .84). There were no significant differences in all postoperative FLACC scales. The mean dose of opioid rescue medication measured as morphine milligram equivalents did not differ between groups (P = .56). Significant postoperative hemorrhage was not observed.

CONCLUSIONS

This is the first prospective study to evaluate the safety and efficacy of single-dose ketorolac after PP. Although lack of standardization between study and historical control groups may have precluded observation of an analgesic benefit, analysis demonstrated a single dose of ketorolac after PP is safe. Further investigations with more patients and different postoperative regimens may clarify the role of ketorolac in improving pain after PP.

The effect of intraoperative dexmedetomidine administration on length of stay in the post-anesthesia care unit in ambulatory surgery: A hospital registry study

STUDY OBJECTIVE

Dexmedetomidine, which is commonly used for procedural sedation and as adjunct to general anesthesia for ambulatory procedures, may affect patient discharge from the post-anesthesia care unit (PACU). We hypothesized that intraoperative dexmedetomidine use in ambulatory surgery is associated with delayed discharge from the PACU and that this is modified by surgical duration and anesthesia type.

DESIGN

Retrospective cohort study.

SETTING

Academic medical center.

PATIENTS

130,854 adult patients undergoing ambulatory surgery between 2008 and 2018.

INTERVENTIONS

Intraoperative administration of dexmedetomidine.

MEASUREMENTS

The primary outcome was PACU length of stay. In secondary and exploratory analyses, we examined dose-dependency, effect modification by duration of surgery and anesthesia type, effects of timing of dexmedetomidine administration, and PACU discharge delays.

MAIN RESULTS

Dexmedetomidine was associated with a prolonged PACU length of stay (adjusted absolute difference [AD_adj] 15.0 min; 95%CI 12.7-17.3; p < 0.001). This effect was dose-dependent (p-for-trend < 0.001), magnified in surgeries of less than one hour (AD_adj 20.7 min; 95%CI 16.7-24.7; p < 0.001) and in patients undergoing monitored anesthesia care compared to general anesthesia (AD_adj 16.8 min; 95%CI 14.1-19.6; p < 0.001). The effect was more pronounced if dexmedetomidine was administered within the last 60 min of surgery (AD_adj 18.7 min; 95%CI 15.7-21.7; p < 0.001). Dexmedetomidine was associated with discharge delays due to cardiovascular complications (OR_adj 2.27; 95%CI 1.59-3.24; p < 0.001) and over-sedation (OR_adj 1.28; 95%CI 1.11-1.48; p < 0.001). In patients who received dexmedetomidine (n = 2901), the use of bolus doses only versus the combination of bolus and infusions, magnified the effects on PACU length of stay (AD_adj 29.5 min per μg/kg; 95%CI 17.3-41.8 versus 18.1 min per μg/kg; 95%CI 11.4-24.8; p < 0.001).

CONCLUSIONS

The intraoperative administration of dexmedetomidine was dose-dependently associated with a prolonged PACU length of stay. Clinicians should judiciously titrate dexmedetomidine, especially when using this long-acting drug for monitored anesthesia care for shorter procedures.

Comparative study of intranasal dexmedetomidine v/s midazolam for sedation of pediatric patients during transthoracic echocardiography

Background

Procedural sedation required to improve the quality of Transthoracic Echocardiography (TTE) in infants and children. The ideal drug and route for sedation in children should have a rapid and reliable onset, atraumatic, palatable with minimal side effects, and rapid recovery. So, the aim of our study to evaluate and compare the efficacy and safety of intranasal midazolam and intranasal dexmedetomidine in pediatric patients for sedation during TTE.

Materials and Method

Hundred children under three year of age, belonging to the American Society of Anaesthesiologists class-I and II, scheduled for TTE were divided into two groups by standard randomization technique. Patients in group-M received intranasal midazolam 0.2 mg/kg, whereas patients in group-D received intranasal dexmedetomidine 2 μg/kg prior to TTE under an adequately monitored anesthesia care. Onset and duration of sedation, heart rate, oxygen saturation, sonographer's, and parent's satisfaction scores were recorded.

Results

All patients were successfully sedated for TTE. The average onset time, sedation time, awakening time and total time for Group-M were 7.3, 18.8, 29.51, 51 min and group-D were 10.1, 14.2, 24.9, 46.3 min, respectively and all were statistically significant (P < 0.001). TTE scan time of Group-M is 8.84 min and Group-D is 9.18 min and was statistically significant. Sonographer's and Parent's average satisfaction score for Group-M was 9.88, 10 and for Group-D was 7.64, 8.76, respectively, which were statistically significant (P < 0.001).

Conclusion

Intranasal midazolam and dexmedetomidine are safe and effective for sedation in TTE. Intranasal midazolam was found to be comparatively more effective in view of onset of action, sonographers, and parental satisfaction score, while sedation time, awakening time and total duration was significantly higher as compared to intranasal dexmedetomidine.

Intranasal drugs for analgesia and sedation in children admitted to pediatric emergency department: a narrative review

Acute pain is one of the most common symptoms in children admitted to the Pediatric Emergency Department (PED) and its management represents a real clinical challenge for pediatricians. Different painful procedures can be very stressful for young children and their perception of pain can be enhanced by emotional factors, such as anxiety, distress, or anger. Adequate procedural sedation reduces anxiety and emotional trauma for the patient, but it reduces also stress for operators and the time for procedures. We have reviewed the literature on this topic and the drugs covered in these papers were: midazolam, fentanyl, ketamine, and dexmedetomidine. There are several routes of administering for these drugs to provide analgesia and anxiolysis to children: oral, parenteral, or intranasal (IN). Intravenous (IV) sedation, since it involves the use of needles, can be stressful; instead, IN route is a non-invasive procedure and generally well tolerated by children and it has become increasingly widespread. Some medications can be administered by a mucosal atomizer device (MAD) or by drops. The benefits of the atomized release include less drug loss in the oropharynx, higher cerebrospinal fluid levels, better patient acceptability, and better sedative effects. IN midazolam has a sedative, anxiolytic and amnesic effect, but without analgesic properties. Fentanyl and ketamine are mainly used for pain control. Dexmedetomidine has anxiolytic and analgesic properties. In conclusion, IN analgo-sedation is a simple, rapid and painless option to treat pain and anxiety in the PED requiring brief training on the administration process and experience in sedation.

Effects on the Upper Airway Morphology with Intravenous Addition of Ketamine after Dexmedetomidine Administration in Normal Children

General anesthesia decreases the tone of upper airway muscles in a dose-dependent fashion, potentially narrowing the pharyngeal airway. We examined the effects of adding ketamine on the airway configuration after dexmedetomidine administration in spontaneously breathing children with normal airways. 25 children presenting for Magnetic Resonance Imaging (MRI) of the brain/spine under general anesthesia were prospectively recruited in the study. Patients were anesthetized with dexmedetomidine bolus (2 mcg over 10 min) followed by dexmedetomidine infusion (2 mcg·kg−1·h) and ketamine and permitted to breathe spontaneously via the native airway. MR-CINE images of the upper airway were obtained with dexmedetomidine infusion alone (baseline) and 5, 10, and 15 min after administering ketamine bolus (2 mg·kg−1) in two anatomical axial planes at the nasopharynx and the retroglossal upper airway. Airway lumen is segmented with a semi-automatic image processing approach using a region-growing algorithm. Outcome measures of cross-sectional area, transverse and anterior-posterior diameters of the airway in axial planes at the level of the epiglottis in the retroglossal airway, and in the superior nasopharynx were evaluated for changes in airway size with sedation. Airway dimensions corresponding to the maximum, mean, and minimum sizes during a respiratory cycle were obtained to compare the temporal changes in the airway size. The dose-response of adding ketamine to dexmedetomidine alone condition on airway dimensions were examined using mixed-effects of covariance models. 22/25 patients based on inclusion/exclusion criteria were included in the final analysis. The changes in airway measures with the addition of ketamine, when compared to the baseline of dexmedetomidine alone, were statistically insignificant. The modest changes in airway dimensions are clinically less impactful and within the accuracy of the semi-automatic airway segmentation approach. The effect sizes were small for most airway measures. The duration of ketamine seems to not affect the airway size. In conclusion, adding ketamine to dexmedetomidine did not significantly reduce upper airway configuration when compared to dexmedetomidine alone.

Dexmedetomidine for EEG sedation in children with behavioral disorders

OBJECTIVE

To evaluate the efficacy and safety of sedation with dexmedetomidine, a highly selective α2-agonist with sedative effect, for EEG recording in children with behavioral disorders.

MATERIAL AND METHODS

Prospective observational study on children with behavioral disorders undergoing EEG at the Pediatric Hospital in Padova, Italy. A 2 mcg/kg intravenous bolus of dexmedetomidine was administered, followed by a 1-2 mcg/kg/h infusion. If necessary, bolus was repeated up to 3 times to reach the target level of sedation, assessed by Pediatric Sedation State Scale. Patients were fully monitored before, during and after the procedure until complete recovery. EEG recording quality, and caregivers' satisfaction were collected. Any adverse effect was registered using SIVA score.

RESULTS

For this preliminary study, 19 patients were enrolled. EEG was successfully completed in all of them. Mean total dose of dexmedetomidine was 3.7 ± 1.7 mcg/kg. Adequate sedation was achieved within 11.9 ± 8 minutes. Mean time to first awakening was 30.9 ± 36.9 minutes and time to complete recovery 113.3 ± 92.7 minutes. Adverse effects (hypotension, bradycardia) were reported in 10 patients, all classified as "minor." EEG recording quality was good or excellent. Parents' satisfaction was high in all the interviewed families.

CONCLUSIONS

Intravenous dexmedetomidine as a single drug showed an excellent efficacy and good safety profile for EEG recording in children with behavioral disorders.

Uncorrected Tetralogy of Fallot's: Anesthetic Challenges

Tetrology of Fallot's (TOF) is the most common cause of cyanotic congenital heart disease, and accounts for 10% of all congenital heart diseases. Right to left shunting and hyperviscosity of blood predisposes these patients to brain abscess. Perioperative management of these patients with uncorrected TOF for noncardiac surgery is a challenge for the anesthesiologists owing to the long-term effects of hypoxia and decreased pulmonary blood flow, resulting in considerable modification of the physiology and neurological complications. We are hereby reporting the anaesthetic management of an 8 year old child with uncorrected TOF presenting with multiple brain abscesses who underwent craniotomy with uneventful recovery.

Dexmedetomidine Mediates Neuroglobin Up-Regulation and Alleviates the Hypoxia/Reoxygenation Injury by Inhibiting Neuronal Apoptosis in Developing Rats

Background

Exploring the effective therapy for neonatal hypoxic-ischemic brain injury is an important goal. This study was designed to investigate how dexmedetomidine (DEX) contribute to hypoxic brain injury.

Methods

Developing Sprague-Dawley rat models of hypoxia/reoxygenation (H/R) injury were constructed to simulate neonatal hypoxic brain injury for DEX treatment. Immunohistochemistry and western blot were performed to measure neuroglobin (Ngb) protein expression in hippocampal tissues. Hippocampal neuron injury and apoptosis were detected by Nissl staining and TUNEL assay, respectively. A Morris water maze (MWM) test was performed to evaluate the long-term learning and memory function.

Results

The expression of Ngb was increased following H/R model establishment and up-regulated by medium and high doses of DEX, but not up-regulated by low doses of DEX. Medium and high doses of DEX alleviated the H/R injury as well as induced the reduction of Nissl bodies and apoptosis. Besides, medium and high doses of DEX down-regulated cytosolic Cyt-c, Apaf-1, and caspase-3 in H/R injury model. MWM test showed that medium and high doses of DEX significantly shortened the escape latency and enhanced the number of platform crossings. However, low doses of DEX have no effect on Nissl bodies, mitochondrial apoptosis, expression of apoptosis-related proteins and long-term learning functions.

Conclusions

DEX induced Ngb expression in H/R rat models. The neuroprotection of DEX-mediated Ngb up-regulation may be achieved by inhibiting neuronal apoptosis through the mitochondrial pathway. Findings indicated that DEX may be useful as an effective therapy for neonatal hypoxic brain injury.

Evaluation of nebulised dexmedetomidine in blunting haemodynamic response to intubation: A prospective randomised study

Background and Aim:

The process of laryngoscopy and endotracheal intubation is associated with intense sympathetic activity, which may precipitate intra-operative complications. Taking the advantage of dexmedetomidine's good bioavailability and rapid absorption through nasal mucosa; we contemplated this study to evaluate the effects of nebulised dexmedetomidine as a premedication in blunting the haemodynamic response to laryngoscopy and tracheal intubation.

Methods:

This prospective, randomised, comparative study was conducted in 100 American Society of Anesthesiologists (ASA) I, II patients. The primary outcome was to evaluate the effects of dexmedetomidine nebulisation in blunting the stress response to laryngoscopy and intubation. The secondary outcome was to study its adverse effects. The study population was divided randomly into two groups. Control group C (n = 50) received nebulisation with 5 ml of normal saline and group D (n = 50) received 1 μg/kg dexmedetomidine 5 ml 10 min before induction in sitting position.

Results:

Demographics were comparable. Following laryngoscopy and intubation, systolic (SBP), diastolic (DBP) and mean arterial pressure (MAP), response entropy (RE) and state entropy (SE) were markedly increased in the control group whereas in group D there was a fall in SBP (at 1 min-126.64 ± 26.37; P 0.01, 5 min-109.50 ± 16.83; P 0.02, 10 min-106.94 ± 17.01; P 0.03), DBP (at 1 min-83.18 ± 17.89; P 0.001, 5 min-66.40 ± 13.88; P 0.001, 10 min- 62.56 ± 14.91; P 0.01) and MAP (at 1 min-99.68 ± 19.22; P 0.001, 5 min- 84.08 ± 13.66; P 0.003, 10 min- 81.74 ± 14.79; P 0.008), RE and SE which was statistically significant (P 0.002). There was a dose sparing effect of propofol in group D; sedation score was comparable.

Conclusion:

Nebulised dexmedetomidine effectively blunts the stress response to laryngoscopy and intubation with no adverse effects.

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.