Comparison of Two Different Intranasal Doses of Dexmedetomidine in Children for Magnetic Resonance Imaging Sedation

Perioperative Staff's Experiences of Premedication for Children

PURPOSE

Providing perioperative care for children who express anxiety or react with negative anxiety-associated consequences can be a challenge. The use of premedication is established as an important intervention for young children before surgery, yet research into care providers' experiences of premedication is limited. The aim of this study was to explore perioperative staff's experiences of premedication for preschool-age children.

DESIGN

A descriptive inductive qualitative study was performed based on focus group discussions.

METHODS

A purposive sample of a team from the operating department with experience in anesthetizing and caring for children in the perioperative period was interviewed in small focus groups: five preoperative and postoperative care nurses, five nurse anesthetists, and five anesthesiologists. The transcribed text was categorized using qualitative content analysis.

FINDINGS

The content analysis revealed three themes: a matter of time, do not wake the sleeping bear, and on responsive tiptoes.

CONCLUSIONS

Care providers must adapt their work to the child's emotional state of mind and needs, allowing time for the child to trust and accept the premedication and for the premedication to reach its peak effect. Premedication provides light sleep preoperatively, which requires careful treatment of the child to avoid emotional reactions, and the postoperative path is most peaceful when the premedication supports a long duration of sedation. Our findings highlight the need for safety precautions and a permissive and flexible organization with the goal of achieving a smooth and safe journey for the child in the perioperative path.

Improving pediatric magnetic resonance imaging safety by enhanced non-technical skills and team collaboration

BACKGROUND

Safe pediatric magnetic resonance imaging (MRI) ideally relies on non-sedative techniques, as avoiding risky sedation is inherently safer. However, in practice, sedation often becomes unavoidable, particularly for younger children or those with anxiety, to ensure motion-free, high-quality imaging. This narrative review explores the current practices and proposes strategies to enhance safety in pediatric MRI examinations.

METHODS

We identified and analyzed 247 studies addressing various aspects of pediatric MRI safety, including sedation protocols, patient monitoring, and team-based management approaches.

RESULTS

Safe sedation requires careful drug selection tailored to individual needs, continuous monitoring, and robust emergency preparedness. While efforts are underway to minimize sedation, safer drug protocols and improved monitoring technologies remain essential. Assembling dedicated MRI teams trained in both technical and non-technical skills-such as situational awareness, communication, and teamwork-supports these strategies. Structured team briefings covering monitoring procedures, emergency scenarios, response protocols, and specific resuscitation roles are also critical. Developing a strong organizational culture that promotes patient safety and continuous learning from incident reports helps ensure ongoing improvements.

CONCLUSIONS

Achieving safe pediatric MRI examinations requires balancing the need for sedation with the goal of minimizing its use. Strengthening collaboration, refining sedation protocols, and implementing advanced safety monitoring systems are essential steps. Further advancements in imaging technologies are also necessary to reliably obtain high-quality scans without sedation, reducing risks and improving patient outcomes.

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.

Scoping review finds insufficient evidence on potential risks of procedural sedation with dexmedetomidine in children

AIM

Dexmedetomidine is commonly used in hospitals for sedation during procedurals. It has been considered safe even though studies have shown that it may cause bradycardia and hypotension. The aim of this study was to map the current evidence regarding potential risks of sedation of children with dexmedetomidine.

METHODS

Two database searches were conducted to gather all articles published through 30 January 2024 that matched the inclusion criteria. PubMed and Embase were chosen for the initial search. Search terms were chosen to create a broad systematic search that would include articles reporting adverse events during procedural sedation on children. From the included articles, data on type of sedation, administration, patient characteristics, endpoints and number of adverse events were collected.

RESULTS

After the initial search, 357 individual papers were screened and 41 papers were included. The most common adverse event reported was bradycardia. In almost 40% of the articles that measured oxygen saturation, one or more incidents of desaturation occurred. 27% reported that interventions to prevent further harm were preformed, most of the interventions were to improve oxygenation.

CONCLUSION

There is a need for further investigation regarding adverse events, especially respiratory adverse events during sedation with dexmedetomidine.

Pharmacokinetics, pharmacodynamics and bioavailability of dexmedetomidine nasal spray in healthy Chinese adults: A phase I clinical trial

Background

Intranasal administration is a convenient route for drug delivery that can be applied for procedural sedation. However, there is currently limited exploration into fixed dosing regimens. This study was to investigate the pharmacokinetics (PK), pharmacodynamics (PD), bioavailability (BA) and safety of dexmedetomidine after fixed doses of intranasal and intravenous administration in healthy male and female subjects.

Methods

Group A subjects received intranasal or intravenous administration in two periods (12 subjects received intranasal dexmedetomidine (Dex) or the intravenous formulation, and four received the corresponding placebo). Groups B to F underwent single-period dose ascending, receiving only the intranasal Dex formulation or the corresponding placebo (the number of subjects receiving the drug/placebo in groups B to F were 12/2, 12/2, 12/2, 10/2, 10/2, respectively), with doses of 75 μg, 125 μg, 150 μg, 175 μg, and 200 μg, respectively. After administration of each group, blood samples were collected to investigate the plasma concentration of dexmedetomidine, adrenaline and noradrenaline using a HPLC-MS/MS method. Ramsay score, blood pressure and heart rate were collected for safety evaluation. Pharmacokinetic parameters (Cmax, Tmax, AUC0-24h,AUC 0 - ∞ , and t1/2) of dexmedetomidine were calculated.

Results

A total of 82 subjects were randomized. One subject withdrew for personal reasons before administration and the other subjects completed the entire study process. At a dose of 25 μg, the absolute bioavailability was 59%. Across the dose range of 25 to 200 μg, the median Tmax was similar (0.5-1 h), and the mean elimination half-life was comparable (3.09-4.28 h), with exposure (Cmax and AUC0-t) increasing with dose. The pharmacokinetics after intranasal spray administration exhibited linear characteristics, although Cmax was similar in the higher dose groups (175 μg and 200 μg). PD results showed that ideal sedation effects (Ramsay score of 3 or higher in at least 90% of subjects) could be achieved within 30 min following intranasal administration of 75 μg or higher doses. All the subjects were well tolerated without any serious adverse events (SAEs).

Conclusion

Dexmedetomidine nasal spray was well tolerated and achieved satisfactory sedation in the dose range of 25-200 μg in Chinese healthy male and female subjects.

Clinical Trial Registration

http://www.chinadrugtrials.org.cn/, identifier CTR20201650.

A randomized clinical trial of intranasal dexmedetomidine versus inhaled nitrous oxide for procedural sedation and analgesia in children

BACKGROUND

Procedural sedation and analgesia is an important part of pediatric emergency care, safe and clinically useful alternatives for adequate management are necessary. The objective of this clinical trial was to evaluate the non-inferiority of intranasal dexmedetomidine to nitrous oxide with respect to analgesia for a painful procedure in children 3-15 years of age.

METHODS

This prospective, equally randomized, open-label, non-inferiority trial was conducted at a Pediatric Emergency Department. Previously healthy children 3-15 years of age, with an extremity fracture or luxation or a burn and requiring procedural sedation and analgesia were eligible. Patients were randomized to receive either intranasal dexmedetomidine or inhaled nitrous oxide. The primary outcome measure was highest pain level during the procedure, assessed with Face, Legs, Activity, Cry, Consolability scale (FLACC). Mann-Whitney U test (continuous variables) and Fisher's test (categorical variables) were used for statistical analysis.

RESULTS

The highest FLACC was median 4 (IQR 3-6) with intranasal dexmedetomidine and median 4 (IQR 2-6) with nitrous oxide. The median of the difference between samples from each group for FLACC was 0 with 95%CI (0-1), thus intranasal dexmedetomidine was not inferior to nitrous oxide with respect to the level of pain during the procedure. The same method for procedural sedation and analgesia would be accepted by 52/74 (82.5%) children and 65/74 (91.5%) parents in the intranasal dexmedetomidine group respectively 59/74 (88.1%) versus 70/74 (94.6%) with nitrous oxide. No serious adverse events were reported.

CONCLUSIONS

The results of this trial support that intranasal dexmedetomidine is not inferior to 50% nitrous oxide in providing analgesia for a painful procedure in children 3-15 years of age and can be considered as an alternative to 50% nitrous oxide for procedural sedation and analgesia.

TRIAL REGISTRATION

EudraCT 201,600,377,317, April 20, 2017. https://eudract.ema.europa.eu/ .

Procedural sedation and analgesia in pediatric diagnostic and interventional radiology: An expert DELPHI consensus document developed by the ITALIAN scientific society of anesthesia, analgesia, resuscitation and intensive care (SIAARTI)

BACKGROUND

Children undergoing diagnostic and interventional radiology procedures often require sedation to achieve immobility and analgesia if the procedure is painful. In the past decades, leading scientific organizations have developed evidence-based guidelines for procedural sedation and analgesia in children outside of the operating room. Their recommendations are being applied to procedural sedation in radiology. However, some questions remain open regarding specific aspects contextualized to the radiology setting, such as elective prone sedation, the urgency of the procedure, when venous access or airway protection is required, and others.

AIMS

To address the unresolved issues of procedural sedation and analgesia in pediatric diagnostic and interventional radiology.

METHODS

An expert panel of pediatricians, pediatric anesthesiologists, intensivists, and neuroradiologists selected topics representative of current controversies and formulated research questions. Statements were developed by reviewing the literature for new evidence, comparing expertise and experience, and expressing opinions. Panelists' agreement with the statements was collected anonymously using the DELPHI method.

RESULTS

Twelve evidence-based or expert opinion incorporate are presented, considering risks, benefits, and applicability.

CONCLUSIONS

This consensus document, developed by a multidisciplinary panel of experts involved in the field, provides statements to improve the quality of decision-making practice in procedural sedation and analgesia in pediatric radiology.

An evaluation of dexmedetomidine in combination with midazolam in pediatric sedation: a systematic review and meta-analysis

BACKGROUND

Dexmedetomidine and midazolam are commonly used sedatives in children. We conducted a systematic review and meta-analysis to compare the safety and effectiveness of sedation provided by dexmedetomidine combined with midazolam versus other sedatives including chloral hydrate, midazolam and other sedatives in pediatric sedation.

METHODS

The Embase, Web of Science, Cochrane Library, and PubMed databases, and Clinicaltrials.gov register of controlled trials were searched from inception to June 2022. All randomized controlled trials used dexmedetomidine-midazolam in pediatric sedation were enrolled. The articles search, data extraction, and quality assessment of included studies were performed independently by two researchers. The success rate of sedation was considered as the primary outcome. The secondary outcomes included onset time of sedation, recovery time of sedation and occurrence of adverse events.

RESULTS

A total of 522 studies were screened and 6 RCTs were identified; 859 patients were analyzed. The administration of dexmedetomidine combined with midazolam was associated with a higher sedation success rate and a lower incidence of nausea and vomiting in computed tomography, magnetic resonance imaging, Auditory Brainstem Response test or fiberoptic bronchoscopy examinations than the other sedatives did (OR = 2.92; 95% CI: 1.39-6.13, P = 0.005, I2 = 51%; OR = 0.23, 95% CI: 0.07-0.68, P = 0.008, I2 = 0%, respectively). Two groups did not differ significantly in recovery time and the occurrence of adverse reactions (WMD = - 0.27, 95% CI: - 0.93 to - 0.39, P = 0.42; OR 0.70; 95% CI: 0.48-1.02, P = 0.06, I2 = 45%. respectively). However, the results of the subgroup analysis of ASA I-II children showed a quicker onset time in dexmedetomidine-midazolam group than the other sedatives (WMD=-3.08; 95% CI: -4.66 to - 1.49, P = 0.0001, I2 = 30%).

CONCLUSIONS

This meta-analysis showed that compared with the control group, dexmedetomidine combined with midazolam group provided higher sedation success rates and caused a lower incidence of nausea and vomiting in completing examinations, indicating a prospective outpatient clinical application for procedural sedation.

Combination of Intranasal Dexmedetomidine and Midazolam for Sedation in Pediatric Magnetic Resonance Imaging: A Retrospective Observational Study

BACKGROUND

Intranasal dexmedetomidine associated with midazolam has been used for pediatric magnetic resonance imaging studies because immobility is a fundamental requirement for correct execution. Many studies have shown dexmedetomidine to be a good option for non-operating room sedation. However, identifying the optimal dose remains a key challenge, especially for pediatric patients.

METHODS

All medical records of 139 pediatric patients who underwent sedation for magnetic resonance imaging studies between September 2021 and November 2022 at the University Hospital of Salerno, Italy, were retrospectively reviewed about success rate and adverse events. Our protocol required dosing 30 minutes before the procedure. Patients weighing up to 40 kg received intranasal dexmedetomidine (3 μg/kg) with intranasal midazolam (0.2 mg/kg). Those weighing more than 40 kg received intranasal dexmedetomidine (2 μg/kg) with midazolam orally (0.3 mg/kg; maximum dose, 15 mg).

RESULTS

A total of 139 pediatric patients, with age range between 2 months and 16 years, median (95% confidence interval) of 3 (3-5) years, and weight range between 4 and 70 kg, median (95% confidence interval) of 19 (15-24) kg, were reviewed.The procedure was satisfactorily completed in 93.5% (130 patients) ( P < 0.01). Only 9 (6.5%) patients completed the procedure with general anesthesia; there are hot adverse events.

CONCLUSIONS

Our experience with association of intranasal dexmedetomidine and midazolam has a high success rate, with high effectiveness and safety.

Application of intranasal dexmedetomidine in magnetic resonance imaging of preterm infants: The ED50, efficacy and safety analysis

BACKGROUND

Infants undergoing magnetic resonance imaging (MRI) often require pharmacological sedation. Dexmedetomidine serves as a novel sedative agent that induces a unique unconsciousness similar to natural sleep, and therefore has currently been used as the first choice for sedation in infants and young children.

OBJECTIVE

To determine the 50% effective dose (ED50) and 95% confidence interval (95%CI) of intranasal dexmedetomidine for MRI in preterm and term infants, and to observe the incidence of adverse events. To explore whether there were differences in ED50 and 95%CI, heart rate (HR) and blood oxygen saturation (SpO2), the induction time and wake-up time and the incidence of adverse events between the 2 groups, so as to provide guidance for clinical safe medication for the meanwhile.

METHODS

A total of 68 infants were prospectively recruited for MRI examination under drug sedation (1 week ≤ age ≤ 23 weeks or weight ≤ 5kg). The children were divided into 2 groups according to whether they had preterm birth experience (Preterm group, Atterm group). The Dixon up-and-down method was used to explore ED50. The basic vital signs of the 2 groups were recorded, and the heart rate and SpO2 were recorded every 5 minutes until the infants were discharged from the hospital. The induction time, wake-up time and adverse events were recorded.

RESULTS

The ED50 (95%CI) of intranasal dexmedetomidine in the Preterm group and the Atterm group were 2.23 (2.03-2.66) μg/kg and 2.64 (2.49-2.83) μg/kg, respectively (P < .05). the wake-up time was longer in Preterm group (98.00min) than in Atterm group (81.00 min) (P < .05), the incidence of bradycardia in Preterm group was 3/33, which was higher than that in Atterm group (1/35). There was no difference in the induction time between the 2 groups (P > .05), and there was no significant difference in other adverse events.

CONCLUSIONS

Intranasal dexmedetomidine can be safely used for sedation in preterm infants undergoing MRI. Compared with term infants, preterm infants have a lower dose of dexmedetomidine, a higher incidence of bradycardia, and a longer weak-up time.

A randomized double-blind trial of intranasal dexmedetomidine versus intranasal esketamine for procedural sedation and analgesia in young children

BACKGROUND

Procedural sedation and analgesia are commonly used in the Emergency Departments. Despite this common need, there is still a lack of options for adequate and safe analgesia and sedation in children. The objective of this study was to evaluate whether intranasal dexmedetomidine could provide more effective analgesia and sedation during a procedure than intranasal esketamine.

METHODS

This was a double-blind equally randomized (1:1) superiority trial of 30 children aged 1-3 years presenting to the Emergency Department with a laceration or a burn and requiring procedural sedation and analgesia. Patients were randomized to receive 2.0 mcg/kg intranasal dexmedetomidine or 1.0 mg/kg intranasal esketamine. The primary outcome measure was highest pain (assessed using Face, Legs, Activity, Cry, Consolability scale (FLACC)) during the procedure. Secondary outcomes were sedation depth, parents' satisfaction, and physician's assessment. Comparisons were done using Mann-Whitney U test (continuous variables) and Fisher's test (categorical variables).

RESULTS

Adequate analgesia and sedation were reached in 28/30 patients. The estimated sample size was not reached due to changes in treatment of minor injuries and logistical reasons. The median (IQR) of highest FLACC was 1 (0-3) with intranasal dexmedetomidine and 5 (2-6.75) with intranasal esketamine, (p-value 0.09). 85.7% of the parents with children treated with intranasal dexmedetomidine were "very satisfied" with the procedure and sedation compared to the 46.2% of those with intranasal esketamine, (p-value 0.1). No severe adverse events were reported during this trial.

CONCLUSIONS

This study was underpowered and did not show any difference between intranasal dexmedetomidine and intranasal esketamine for procedural sedation and analgesia in young children. However, the results support that intranasal dexmedetomidine could provide effective analgesia and sedation during procedures in young children aged 1-3 years with minor injuries.

TRIAL REGISTRATION

Eudra-CT 2017-00057-40, April 20, 2017. https://eudract.ema.europa.eu/.

Effect of two different doses of nalbuphine for postoperative analgesia in children with cleft palate: a randomized controlled trial

BACKGROUND

Cleft palate repair surgery may result in severe pain in the immediate postoperative period. The aim of this study is to compare the effects of different doses of nalbuphine for postoperative analgesia in children with cleft palate.

METHODS

From November 2019 to June 2021, 90 children (45 males and 45 females, age 9-20 months old, ASA class I-II) were selected for palatoplasty. They were randomly divided into three groups: the control group (Group C), the N1 group (postoperative analgesia with 0.05 mg/kg/h nalbuphine) and the N2 group (postoperative analgesia with 0.075 mg/kg/h nalbuphine). Each group had 30 cases. Nalbuphine was not continuously infused in Group C but was continuously infused in Groups N1 and N2 at rates of 0.05 mg/kg/h and 0.075 mg/kg/h, respectively, for 24 h for postoperative analgesia. The FLACC analgesia score and Ramsay Sedation score were recorded at 10 min (T1), 30 min (T2), 2 h (T3), 12 h (T4) and 24 h (T5) after the operation. Adverse reactions such as nausea, vomiting and respiratory depression were observed and recorded.

RESULTS

Compared with those in Group C, the FLACC scores in the N1 and N2 groups decreased significantly at T1-T5 (p < 0.05); the Ramsay Sedation score in the N1 group was significantly higher at T3 and T4 (p < 0.05), and that in the N2 group was significantly higher at T1-T5 (p < 0.05). Compared with that in the N1 group, the FLACC score in the N2 group was not significantly different, and the Ramsay Sedation score increased significantly at T5 (p < 0.05).

CONCLUSION

Using 0.05 mg/kg/h Nalbuphine continuously for 24 h for postoperative analgesia in children with cleft palate has a better effect and fewer adverse reactions.

TRIAL REGISTRATION

This study was registered at ChiCTR1900027385 (11/11/2019).

Efficacy of intranasal administration of dexmedetomidine in combination with midazolam for sedation in infant with cleft lip and palate undergoing CT scan: a randomized controlled trial

BACKGROUND

There is a great challenge to sedation for infants with cleft lip and palate undergoing CT scan, because there is the younger age and no consensus on the type, dosage, and route of drug administration.

OBJECTIVE

This study aimed to evaluate the efficacy of intranasal administration of dexmedetomidine combined with midazolam as a sedative option for infants with cleft lip and palate under imaging procedures.

METHODS

Infants scheduled for cleft lip and palate repair surgery were randomly assigned to the IND group (intranasal dexmedetomidine 2 µg/kg alone) and the INDM group (intranasal dexmedetomidine 2 µg/kg combined with midazolam 0.05 mg/kg). The primary outcome was the proportion of infants underwent successful computed tomography (CT) scans under intranasal sedation. The secondary outcomes included onset time and duration of sedation, recovery time, Ramsay sedation scale, hemodynamic parameters during sedation, and adverse events. Data analyses involved the unpaired t-test, the repeated-measures analysis of variance test, and the continuity correction χ2 test.

RESULTS

One hundred five infants were included in the analysis. The proportion of infants underwent successful CT scans under sedation was significantly greater in the INDM group than in the IND group (47 [95.9%] vs. 45 [80.4%], p = 0.016). Additionally, the INDM group had a shorter onset time and a longer duration of sedation statistically (12 [8.5, 17] min vs. 16 [12, 20] min, p = 0.001; 80 [63.6, 92.5] min vs. 68.5 [38, 89] min, p = 0.014, respectively), and their recovery time was significantly longer (43 [30, 59.5] min vs. 31.5 [20.5, 53.5] min, p = 0.006). The difference in Ramsay sedation scale values 20 min after administration was statistically significant between the groups. No statistically significant difference was found between the groups in changes in heart rate and respiratory rate.

CONCLUSION

Intranasal administration of dexmedetomidine in combination with midazolam resulted in higher sedation success in comparison with sole dexmedetomidine. However, it has a relatively prolonged duration of sedation and recovery time.

TRIAL REGISTRATION

ChiCTR2100049122, Clinical trial first registration date: 21/07/2021.

Intranasal dexmedetomidine for transthoracic echocardiography in infants with shunt-dependent single ventricle heart disease

OBJECTIVES

We investigated the efficacy and complication profile of intranasal dexmedetomidine for transthoracic echocardiography sedation in patients with single ventricle physiology and shunt-dependent pulmonary blood flow during the high-risk interstage period.

METHODS

A single-centre, retrospective review identified interstage infants who received dexmedetomidine for echocardiography sedation. Baseline and procedural vitals were reported. Significant adverse events related to sedation were defined as an escalation in care or need for any additional/increased inotropic support to maintain pre-procedural haemodynamics. Minor adverse events were defined as changes from baseline haemodynamics that resolved without intervention. To assess whether sedation was adequate, echocardiogram reports were reviewed for completeness.

RESULTS

From September to December 2020, five interstage patients (age 29-69 days) were sedated with 3 mcg/kg intranasal dexmedetomidine. The median sedation onset time and duration time was 24 minutes (range 12-43 minutes) and 60 minutes (range 33-60 minutes), respectively. Sedation was deemed adequate in all patients as complete echocardiograms were accomplished without a rescue dose. When compared to baseline, three (60%) patients had a >10% reduction in heart rate, one (20%) patient had a >10% reduction in oxygen saturations, and one (20%) patient had a >30% decrease in blood pressure. Amongst all patients, no significant complications occurred and haemodynamic changes from baseline did not result in need for intervention or interruption of study.

CONCLUSIONS

Intranasal dexmedetomidine may be a reasonable option for echocardiography sedation in infants with shunt-dependent single ventricle heart disease, and further investigation is warranted to ensure efficacy and safety in an outpatient setting.

Perioperative management and drug selection for sedated/anesthetized patients undergoing MRI examination: A review

In recent years, magnetic resonance imaging (MRI) technology has become an indispensable imaging tool owing to significant improvements in MRI that have opened up new diagnostic perspectives. Due to the closed environment, long imaging time, and need to remain still during the examination process, the examiner may cannot cooperate with the completion of the examination of the procedure, which increases the need for deep sedation or anesthesia. Achieving this can sometimes be challenging, especially in the special nontraditional environment of MRI equipment (unfamiliar and narrow spaces, away from patients, strong magnetic fields) and in special populations requiring sedation/anesthesia during examinations, which pose certain challenges for the perioperative anesthesia management of MRI. A simple "checklist" is necessary because it allows the anesthesiologist to become familiar with the particular environment and human and material resources as quickly as possible. For the choice of sedative/anesthetic, the traditional drugs, such as midazolam and ketamine, are still used due to the ease of administration despite their low sedation success rate, prolonged recovery, and significant adverse events. Currently, dexmedetomidine, with respiratory drive preservation, propofol, with high effectiveness and rapid recovery, and sevoflurane, which is mild and nonirritating, are preferred for sedation/anesthesia in children and adults undergoing MRI. Therefore, familiarity with the perioperative management of patient sedation and general anesthesia and drug selection in the MRI environment is critical for successful surgical completion and for the safe and rapid discharge of MRI patients receiving sedation/anesthesia.

Optimal Dose of Intranasal Dexmedetomidine for Laceration Repair in Children: A Phase II Dose-Ranging Study

STUDY OBJECTIVE

To determine the optimal sedative dose of intranasal dexmedetomidine for children undergoing laceration repair.

METHODS

This dose-ranging study employing the Bayesian Continual Reassessment Method enrolled children aged 0 to 10 years with a single laceration (<5 cm), requiring single-layer closure, who received topical anesthetic. Children were administered 1, 2, 3, or 4 mcg/kg intranasal dexmedetomidine. The primary outcome was the proportion with adequate sedation (Pediatric Sedation State Scale score of 2 or 3 for ≥90% of the time from sterile preparation to tying of the last suture). Secondary outcomes included the Observational Scale of Behavior Distress-Revised (range: 0 [no distress] to 23.5 [maximal distress]), postprocedure length of stay, and adverse events.

RESULTS

We enrolled 55 children (35/55 [64%] males; median [interquartile range {IQR}] age 4 [2, 6] years). At 1, 2, 3, and 4 mcg/kg intranasal dexmedetomidine, respectively, the proportion of participants "adequately" sedated was 1/3 (33%), 2/9 (22%), 13/21 (62%), and 12/21 (57%); the posterior mean (95% equitailed credible intervals) for the probability of adequate sedation was 0.38 (0.04, 0.82), 0.25 (0.05, 0.54), 0.61 (0.41, 0.80), and 0.57 (0.36, 0.76); the median (IQR) Observational Scale of Behavior Distress-Revised scores during suturing was 2.7 (0.3, 3), 0 (0, 3.8), 0.6 (0, 5), and 0 (0, 3.7); the median (IQR) postprocedure length of stay was 67 (60, 78), 76 (60, 100), 89 (76, 109), and 113 (76, 150) minutes. There was 1 adverse event, a decrease in oxygen saturation at 4 mcg/kg, which resolved with head repositioning.

CONCLUSION

Despite limitations, such as our limited sample size and subjectivity in Pediatric Sedation State Scale scoring, sedation efficacy for 3 and 4 mcg/kg were similarly based on equitailed credible intervals suggesting either could be considered optimal.

Comparison of oral triclofos and intranasal midazolam and dexmedetomidine for sedation in children undergoing magnetic resonance imaging (MRI): an open-label, three-arm, randomized trial

The purpose of this study was to compare the efficacy of oral triclofos (TRI), intranasal midazolam (INM), and intranasal dexmedetomidine (IND) in achieving successful sedation in children undergoing MRI. This open-label, three-arm, randomized trial was conducted in a tertiary care teaching hospital over 18-month period. Children scheduled for MRI were enrolled. Rate of successful/adequate sedation was assessed using the Paediatric Sedation State Scale (PSSS). The primary outcome was the efficacy (successful sedation or sedation rate) of the three drugs. One-hundred and ninety-five children were included for the MRI procedure. IND was found to be superior in terms of achieving successful sedation. INM had a shorter onset and duration of sedation compared to IND and TRI, but with an increased failure rate (88.3%). Keeping INM as the reference group, it was found that the odds of sedation increased 4.1 times on changing from INM to IND (p < 0.01), and 2.26 times on changing from INM to TRI (p < 0.01). Adverse events included nasal discomfort (18.3%) in INM group; and self-limited tachycardia (4.6%) and hypotension (10.8%) in the IND group.

CONCLUSION

IND was more efficacious than INM or TRI for procedural sedation in children undergoing MRI without any significant adverse events.

CLINICAL TRIAL REGISTRATION

CTRI/2019/01/017257; date registered: 25/01/2019.

WHAT IS KNOWN

• Oral triclofos (TRI) and intranasal midazolam (INM) have been used for procedural sedation in children undergoing MRI with variable success; but the experience with intranasal dexmedetomidine (IND) is limited.

WHAT IS NEW

• IND provides more effective sedation compared to INM or TRI for procedural sedation in children undergoing MRI, without any significant adverse events.

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.

Needle-free pharmacological sedation techniques in paediatric patients for imaging procedures: a systematic review and meta-analysis

BACKGROUND

Sedation techniques and drugs are increasingly used in children undergoing imaging procedures. In this systematic review and meta-analysis, we present an overview of literature concerning sedation of children aged 0-8 yr for magnetic resonance imaging (MRI) procedures using needle-free pharmacological techniques.

METHODS

Embase, MEDLINE, Web of Science, and Cochrane databases were systematically searched for studies on the use of needle-free pharmacological sedation techniques for MRI procedures in children aged 0-8 yr. Studies using i.v. or i.m. medication or advanced airway devices were excluded. We performed a meta-analysis on sedation success rate. Secondary outcomes were onset time, duration, recovery, and adverse events.

RESULTS

Sixty-seven studies were included, with 22 380 participants. The pooled success rate for oral chloral hydrate was 94% (95% confidence interval [CI]: 0.91-0.96); for oral chloral hydrate and intranasal dexmedetomidine 95% (95% CI: 0.92-0.97); for rectal, oral, or intranasal midazolam 36% (95% CI: 0.14-0.65); for oral pentobarbital 99% (95% CI: 0.90-1.00); for rectal thiopental 92% (95% CI: 0.85-0.96); for oral melatonin 75% (95% CI: 0.54-0.89); for intranasal dexmedetomidine 62% (95% CI: 0.38-0.82); for intranasal dexmedetomidine and midazolam 94% (95% CI: 0.78-0.99); and for inhaled sevoflurane 98% (95% CI: 0.97-0.99).

CONCLUSIONS

We found a large variation in medication, dosage, and route of administration for needle-free sedation. Success rates for sedation techniques varied between 36% and 98%.

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.

Population Pharmacokinetics of Intranasal Dexmedetomidine in Infants and Young Children

BACKGROUND

Intranasal dexmedetomidine provides noninvasive, effective procedural sedation for pediatric patients, and has been widely used in clinical practice. However, the dosage applied has varied fourfold in pediatric clinical studies. To validate an appropriate dosing regimen, this study investigated the pharmacokinetics of intranasal dexmedetomidine in Chinese children under 3 yr old.

METHODS

Intranasal dexmedetomidine 2 µg · kg-1 was administered to children with simple vascular malformations undergoing interventional radiological procedures. A population pharmacokinetic analysis with data from an optimized sparse-sampling design was performed using nonlinear mixed-effects modeling. Clearance was modeled using allometric scaling and a sigmoid postmenstrual age maturation model. Monte Carlo simulations were performed to assess the different dosing regimens.

RESULTS

A total of 586 samples from 137 children aged 3 to 36 months were included in the trial. The data were adequately described by a two-compartment model with first-order elimination. Body weight with allometric scaling and maturation function were significant covariates of dexmedetomidine clearance. The pharmacokinetic parameters for the median subjects (weight 10 kg and postmenstrual age 101 weeks) in the authors' study were apparent central volume of distribution 7.55 l, apparent clearance of central compartment 9.92 l · h-1, apparent peripheral volume of distribution 7.80 l, and apparent intercompartmental clearance 61.7 l · h-1. The simulation indicated that at the dose of 2 µg · kg-1, 95% of simulated individuals could achieve a target therapeutic concentration of 0.3 ng · ml-1 within 20 min, and the average peak concentration of 0.563 ng · ml-1 could be attained at 61 min.

CONCLUSIONS

The pharmacokinetic characteristics of intranasal dexmedetomidine were evaluated in Chinese pediatric patients aged between 3 and 36 months. An evidence-based dosing regimen at 2 µg · kg-1 could achieve a preset therapeutic threshold of mild to moderate sedation that lasted for up to 2 h.

EDITOR’S PERSPECTIVE

Dexmedetomidine - An emerging option for sedation in neonatal patients

Dexmedetomidine is a sedative agent with limited dosing, safety, and efficacy information in the neonatal population. This comprehensive review describes the available evidence summarizing the use of dexmedetomidine in various neonatal populations. We identified 21 studies and 1 case report supporting the efficacy and short-term safety of DEX in neonates. Reported dosing ranges from 0.5-1.5 mcg/kg/h with or without loading doses. Clinically relevant adverse effects include bradycardia and hypotension. Future studies are needed to determine long-term safety and facilitate clinical applicability.

Intranasal dexmedetomidine: the ideal drug for sedation in the pediatric echo lab?

BACKGROUND

Intranasal dexmedetomidine is an attractive option for procedural sedation in pediatrics due to ease of administration and its relatively short half-life. This study sought to compare the safety and efficacy of intranasal dexmedetomidine to a historical cohort of pediatric patients sedated using chloral hydrate in a pediatric echo lab.

METHODS

Chart review was performed to compare patients sedated between September, 2017 and October, 2019 using chloral hydrate and intranasal dexmedetomidine. Vital signs, time to sedation, duration of sedation, need for second dose of medication, rate of failed sedation, and impact on vital signs were compared between groups. Subgroup analysis was performed for those with complex and cyanotic heart disease.

RESULTS

Chloral hydrate was used in 356 patients and intranasal dexmedetomidine in 376. Patient age, complexity of heart disease, and duration of sedation were similar. Rates of failed sedation were very low and similar. Average heart rate and minimum heart rate were lower for those receiving intranasal dexmedetomidine than chloral hydrate. Impact on vital signs was similar for those with complex and cyanotic heart disease. No adverse events occurred in either group.

CONCLUSIONS

Sedation with intranasal dexmedetomidine is comparable to chloral hydrate in regards to safety and efficacy for children requiring echocardiography. Consistent with the mechanism of action, patients receiving intranasal dexmedetomidine have a lower heart rate without morbidity.

Using intranasal dexmedetomidine with buccal midazolam for magnetic resonance imaging sedation in children: A single-arm prospective interventional study

OBJECTIVE

Although numerous intravenous sedative regimens have been documented, the ideal non-parenteral sedation regimen for magnetic resonance imaging (MRI) has not been determined. This prospective, interventional study aimed to investigate the efficacy and safety of buccal midazolam in combination with intranasal dexmedetomidine in children undergoing MRI.

METHODS

Children between 1 month and 10 years old requiring sedation for MRI examination were recruited to receive buccal midazolam 0.2 mg⋅kg^-1 with intranasal dexmedetomidine 3 μg⋅kg^-1. The primary outcome was successful sedation following the administration of the initial sedation regimens and the completion of the MRI examination.

RESULTS

Sedation with dexmedetomidine-midazolam was administered to 530 children. The successful sedation rate was 95.3% (95% confidence interval: 93.5-97.1%) with the initial sedation regimens and 97.7% (95% confidence interval: 96.5-99%) with a rescue dose of 2 μg⋅kg^-1 intranasal dexmedetomidine. The median sedation onset time was 10 min, and a significant rising trend was observed in the onset time concerning age (R = 0.2491, P < 0.001). The wake-up and discharge times significantly correlated with the duration of the procedure (R = 0.323, P < 0.001 vs. R = 0.325, P < 0.001). No oxygen deficiency nor medication intervention due to cardiovascular instability was observed in any of the patients. History of a prior failed sedation was considered a statistically significant risk factor for failed sedation in the multivariate logistic regression model [odds ratio = 4.71 (95% confidence interval: 1.24-17.9), P = 0.023].

CONCLUSION

In MRI examinations, the addition of buccal midazolam to intranasal dexmedetomidine is associated with a high success rate and a good safety profile. This non-parenteral sedation regimen can be a feasible and convenient option for short-duration MRI in children between 1 month and 10 years.

Validation of the Ramsay scale for invasive procedures under deep sedation in pediatrics

BACKGROUND

The Ramsay scale is the most widely used scale during pediatric procedures although it has not been formally validated.

OBJECTIVE

To validate the Ramsay scale during invasive procedures under sedation in pediatrics.

METHODS

A prospective analytic study was conducted in two hospitals. All patients ≥6 months that were undergoing invasive procedures under sedation were enrolled. All were recorded, and these videos were edited and randomized. 150 videos were scored by four observers (a pediatrician, a pediatric intensive care unit nurse, an anesthetist, and an operating room nurse). All videos were scored with the Ramsay scale and University of Michigan Sedation Scale. Observers were blinded to drug administration. Construct validity was measured through Wilcoxon test paired samples after administration of sedatives. Criterion validity, intra-observer reliability, and interobserver correlation were evaluated by comparing the scores of the scales using Spearman's correlation coefficient. Interobserver agreement was measured using the intraclass correlation coefficient. To assess test-retest reliability, 50 videos were randomly selected and reevaluated.

RESULTS

Sixty-five patients were included. Construct validity was demonstrated through changes in the Ramsay scale scoring after administration of sedatives (p < .0001). Regarding criterion validity, the Ramsay scale had a high correlation with the UMSS (ρ = 0.621). Intra-observer agreement was ρ = 0.884. The Ramsay scale showed interobserver reliability with an intraclass correlation coefficient = 0.94 when comparing it with the University of Michigan Sedation Scale. Internal consistency was α = 0.91. Regarding applicability, in our study, it was applied in two hospitals in different areas by four professionals from distinct categories.

CONCLUSIONS

The Ramsay scale is valid, reliable, and applicable to monitoring sedation for invasive procedures under deep sedation in pediatrics.

Comparison of Low-Dose Sevoflurane Inhalation With Intranasal Ketamine as Rescue Sedation After Intranasal Dexmedetomidine Failure in Outpatient Children Undergoing MRI: A Randomized Control Trial

PURPOSE

The present study aimed to evaluate the effectiveness and safety of low-dose inhalation of sevoflurane through a face mask as a rescue remedy for sedation compared with intranasal ketamine in outpatient children undergoing magnetic resonance imaging (MRI).

DESIGN

A prospective randomized control study. A total of 336 children scheduled for 3.0T MRI but were inadequately sedated after initial intranasal dexmedetomidine (3 μg/kg) were randomly divided into two groups.

METHODS

We used the following protocol for each group: group S, inhalation of low-dose sevoflurane (end-expiratory concentration, 0.4%) through a face mask; group K, intranasal ketamine (2 mg/kg). The success rates were compared between groups as the primary endpoint. The induction time, scan time, recovery time, time to return to baseline functional status, parental and radiologist satisfaction, occurrence of adverse events, and other secondary endpoints were also compared.

FINDINGS

Successful rescue sedation in groups S and K was achieved in 160 (95.2%) and 138 (82.1%) patients, respectively. Compared with group K, group S needed fewer repeat sequences and showed a significantly shorter induction time (5.7 ± 0.5 vs. 10.9 ± 2.7 min; P < 0.001), recovery time (27.4 ± 6.3 vs. 53.8 ± 15.2 min; P < 0.001), and time to return to baseline functional status (3.4 ± 0.6 vs. 6.1 ± 1.1 h; P < 0.001). Radiologist satisfaction, parental satisfaction, and parental desire to repeat the same sedation method were significantly higher in the sevoflurane group.

CONCLUSION

Our results suggest that the inhalation of low-dose sevoflurane through a face mask can provide effective and safe rescue sedation in 1- to 6-year-old outpatient children undergoing MRI, and yields a higher success rate, shorter induction and recovery times, and higher satisfaction than the intranasal ketamine method.

Factors affecting successful use of intranasal dexmedetomidine: a cohort study from a national paediatrics tertiary centre

BACKGROUND

Use of intranasal (IN) dexmedetomidine for procedural sedation has been reported in recent years. Good patient selection is important to ensure high success rates. We aimed to identify factors that influence the successful use of IN dexmedetomidine in non-invasive investigations.

METHODS

All paediatric patients who received IN dexmedetomidine for investigations between 01 July 2019 to 01 July 2020 were included. Baseline demographics, time to reach adequate sedation level, duration of sedation, dose, indications for sedation and need for rescue sedatives were recorded. Procedures were classified into "long" or "short" according to completion time. Successful sedation was defined by completion of investigations by IN dexmedetomidine alone.

RESULTS

Of 105 patients included, median age was 20.0 months, and median weight 11.0 kg. Magnetic resonance imaging (56, 53.3%) was the most common indication. Sixty (57.1%) were successfully sedated using IN dexmedetomidine alone. Automated auditory brainstem response, computerised tomography and mercaptoacetyltriglycine-3 renogram scans had the highest success rate (83.3%, 83.3%, and 100% respectively). On multivariate analysis, short procedures had an adjusted odds ratio of 5.30 (95% CI: 1.69-16.61; P=0.004) compared to long procedures.

CONCLUSIONS

IN dexmedetomidine is effective for procedural sedation for paediatric patients. The most important predictor for sedation success was indication of sedation and duration of procedures.

The 90% effective dose of intranasal dexmedetomidine for procedural sedation in children with congenital heart disease before and after surgery: A biased-coin design up-and-down sequential allocation trial

BACKGROUND

Intranasal dexmedetomidine can provide adequate sedation during short procedures. However, there are few reports investigating the effective dose of intranasal dexmedetomidine for sedation in children with congenital heart disease (CHD) before and after surgery.

METHODS

Children aged 13-36 months with acyanotic CHD requiring trans-thoracic echocardiography before cardiac surgery were recruited for this study. One month after the cardiac surgery, the same children were studied again. The 90% effective dose was established using a biased-coin design up-and-down sequential method. Onset time, examination time, wake-up time and adverse effects were measured. Safety was evaluated in terms of changes in vital signs.

RESULTS

A total of fifty-eight subjects were recruited for this study. The 90% effective dose of intranasal dexmedetomidine for sedation was 2.13 μg/kg (95% CI, 1.73-2.34 μg/kg) in children with CHD before cardiac surgery and 3.51 μg/kg (95% CI, 2.99-3.63 μg/kg) after cardiac surgery (P < .01). There were no differences between the groups in terms of demographic variables, onset time, examination time, wake-up time or adverse effects.

CONCLUSIONS

The 90% effective dose of intranasal dexmedetomidine for sedation in children with CHD was 2.13 μg/kg before cardiac surgery and 3.51 μg/kg after cardiac surgery.

Systematic review and meta-analysis found that intranasal dexmedetomidine was a safe and effective sedative drug during paediatric procedural sedation

AIM

This systematic review and meta-analysis evaluated the effectiveness of intranasal dexmedetomidine as a sole sedative during paediatric procedural sedation outside the operating room.

METHODS

Relevant literature identified by PubMed, Scopus, ClinicalTrials.gov, ScienceDirect and Cochrane Library up to 31 December 2019 was systematically reviewed. Randomised controlled trials that compared intranasal dexmedetomidine with another sedative or placebo during paediatric procedural sedation were included. Trials that studied intranasal dexmedetomidine as a premedication before anaesthesia were excluded. The primary outcome was the success of the planned procedure.

RESULTS

We analysed seven randomised controlled trials of 730 patients: four trials with 570 patients compared dexmedetomidine with chloral hydrate and three trials with 160 patients compared dexmedetomidine with midazolam. The incidence of successfully completing the procedure did not differ between dexmedetomidine and chloral hydrate, but dexmedetomidine had a higher success rate than midazolam. The incidence of hypotension, bradycardia or respiratory complications did not differ between the sedatives used. Nausea and vomiting were more common in children treated with chloral hydrate than in those treated with other sedatives.

CONCLUSION

Intranasal dexmedetomidine was a safe and effective sedative for minor paediatric procedures.

Dexmedetomidine: What's New for Pediatrics? A Narrative Review

Over the past few years, despite the lack of approved pediatric labelling, dexmedetomidine’s (DEX) use has become more prevalent in pediatric clinical practice as well as in research trials. Its respiratory-sparing effects and bioavailability by various routes are only some of the valued features of DEX. In recent years the potential organ-protective effects of DEX, with the possibility for preserving neurocognitive function, has put it in the forefront of clinical and bench research. This comprehensive review focused on the pediatric literature but presents relevant, supporting adult and animal studies in order to detail the recent growing body of literature around the pharmacology, end-organ effects, organ-protective effects, alternative routes of administration, synergetic effects, and clinical applications, with considerations for the future.

Value of Adding Dexmedetomidine in Endoscopic Ultrasound-Guided Celiac Plexus Neurolysis for Treatment of Pancreatic Cancer-Associated Pain

BACKGROUND

Abdominal and back pain is present in up to 80% of patients with pancreatic cancer and represents a significant cause of morbidity. Celiac plexus neurolysis (CPN) demonstrated good results in relief of pain of upper abdominal malignancy. Dexmedetomidine is alpha-2 adrenoceptor highly selective agonist approved for procedural sedation use.

PATIENTS AND METHODS

Fifty patients divided in two groups with locally advanced pancreatic cancer-associated abdominal pain underwent endoscopic ultrasound (EUS)-guided CPN using bupivacaine 0.5% alone with alcohol for the first group and bupivacaine 0.5% plus dexmedetomidine in the second. Patients scored their pain according to the Numeric Rating Scale (NRS-11) before, 2, 4, 6, 8, 12, 16, and 24 week after the procedure.

RESULTS

The study has included 50 patient in two groups. There was no significant difference between the two groups as regards medical, laboratory, or tumor characters. The median pain score decreases from 8.32 ± 0.75 before the procedure to 3.75 ± 3.72 24 week after the procedure in group 1 and from 8.08 ± 0.86 before to 1.67 ± 2.3 24 week after the procedure in group 2. However, there was no significant difference between the two groups in the median pain score during the first 4 weeks. There was no statistically significant difference between the two groups as regards the median survival time.

CONCLUSION

The addition of dexmedetomidine to bupivacaine 0.5% in EUS-CPN demonstrated beneficial effects as regards the degree and duration of pain relieve with negligible effect on the patient survival.

Drug selection for sedation and general anesthesia in children undergoing ambulatory magnetic resonance imaging

The demand for drug-induced sedation for magnetic resonance imaging (MRI) scans have substantially increased in response to increases in MRI utilization and growing interest in anxiety in children. Understanding the pharmacologic options for deep sedation and general anesthesia in an MRI environment is essential to achieve immobility for the successful completion of the procedure and ensure rapid and safe discharge of children undergoing ambulatory MRI. For painless diagnostic MRI, a single sedative/anesthetic agent without analgesia is safer than a combination of multiple sedatives. The traditional drugs, such as chloral hydrate, pentobarbital, midazolam, and ketamine, are still used due to the ease of administration despite low sedation success rate, prolonged recovery, and significant adverse events. Currently, dexmedetomidine, with respiratory drive preservation, and propofol, with high effectiveness and rapid recovery, are preferred for children undergoing ambulatory MRI. General anesthesia using propofol or sevoflurane can also provide predictable rapid time to readiness and scan times in infant or children with comorbidities. The selection of appropriate drugs as well as sufficient monitoring equipment are vital for effective and safe sedation and anesthesia for ambulatory pediatric MRI.

Intranasal dexmedetomidine for sedation in children; a review

Dexmedetomidine is an α2 adrenoreceptor agonist that may be administered by the intranasal route as a sole sedative agent in children. It is odourless, colourless and tasteless and is formulated in a concentration of 100µg.ml^-1. We performed a review of published randomised controlled trials in order to determine the efficacy of intranasal dexmedetomidine for sedation in children. Fourteen trials were eligible for inclusion in the review and contained a total of 1809 patients ranging in age from one month to 14 years. Intranasal dexmedetomidine was administered in a dose range of 1-4µg.kg^-1 and was compared with various other sedatives. Dexmedetomidine was administered by either drops or a mucosal atomiser device. The procedures ranged from non-painful examinations such as magnetic resonance imaging scans and transthoracic echocardiography to painful procedures such as dentistry and venous cannulation. Administration of 2µg.kg^-1 appears to be the optimal dose.

Intrathecal dexmedetomidine and postoperative pain: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND AND OBJECTIVE

A systematic review and meta-analysis of randomized controlled trials (RCTs) was undertaken to evaluate the effect of intrathecal dexmedetomidine (DEX) on the duration of postoperative analgesia, postoperative pain scores and incidences of adverse effects.

DATABASES AND DATA TREATMENT

Database search was performed from inception until January 2019. All RCTs analysing acute postoperative pain characteristics after intrathecal DEX administration in adults undergoing spinal anaesthesia for elective surgery were included. The primary outcome was postoperative analgesic duration, defined as the time to first analgesic request. The secondary outcomes included pain scores at 6, 12 and 24 postoperative hours and rates of hypotension, bradycardia, shivering and postoperative nausea and vomiting.

RESULTS

Twenty-four studies comprising a total of 1,460 patients were included. Postoperative analgesic duration was prolonged with intrathecal DEX compared to placebo, with a pooled mean difference (MD) of 191.3 min (95% CI 168.8-213.8). Patients who received intrathecal DEX reported lower Visual Analogue Scale scores at 24 postoperative hours compared with those patients receiving placebo, with a MD (95% CI) of -1.05 (-1.89 to -0.20, p = 0.02). There were no differences in the incidence of adverse effects, except for a lower rate of postoperative shivering in the intrathecal DEX group (pooled relative risk 0.58, 95% CI 0.34-0.98, p = 0.04).

CONCLUSIONS

Compared to placebo, intrathecal DEX prolonged postoperative analgesic duration, reduced 24-hr pain intensity and reduced the incidence of shivering without an increase in other adverse effects.

SIGNIFICANCE

The analgesic role of intrathecal DEX is promising due to its ability to significantly increase postoperative analgesic duration when compared with placebo. Its usage can be considered for patients undergoing surgeries with significant postoperative pain, particularly those intolerant of systemic analgesia. However, the optimal dose for various surgeries as well as its long-term neurological effects warrants further studies.

Intranasal Dexmedetomidine for Procedural Distress in Children: A Systematic Review

CONTEXT

Intranasal dexmedetomidine (IND) is an emerging agent for procedural distress in children.

OBJECTIVE

To explore the effectiveness of IND for procedural distress in children.

DATA SOURCES

We performed electronic searches of Medline (1946-2019), Embase (1980-2019), Google Scholar (2019), Cumulative Index to Nursing and Allied Health Literature (1981-2019), and Cochrane Central Register.

STUDY SELECTION

We included randomized trials of IND for procedures in children.

DATA EXTRACTION

Methodologic quality of evidence was evaluated by using the Cochrane Collaboration's risk of bias tool and the Grading of Recommendations Assessment, Development, and Evaluation system, respectively. The primary outcome was the proportion of participants with adequate sedation.

RESULTS

Among 19 trials (N = 2137), IND was superior to oral chloral hydrate (3 trials), oral midazolam (1 trial), intranasal midazolam (1 trial), and oral dexmedetomidine (1 trial). IND was equivalent to oral chloral hydrate (2 trials), intranasal midazolam (2 trials), and intranasal ketamine (3 trials). IND was inferior to oral ketamine and a combination of IND plus oral ketamine (1 trial). Higher doses of IND were superior to lower doses (4 trials). Adverse effects were reported in 67 of 727 (9.2%) participants in the IND versus 98 of 591 (16.6%) in the comparator group. There were no reports of adverse events requiring resuscitative measures.

LIMITATIONS

The adequacy of sedation was subjective, which possibly led to biased outcome reporting.

CONCLUSIONS

Given the methodologic limitations of included trials, IND is likely more effective at sedating children compared to oral chloral hydrate and oral midazolam. However, this must be weighed against the potential for adverse cardiovascular effects.

Fifty Percent Effective Dose of Intranasal Dexmedetomidine Sedation for Transthoracic Echocardiography in Children With Cyanotic and Acyanotic Congenital Heart Disease

OBJECTIVES

To determine the 50% and 95% effective dose of intranasal dexmedetomidine sedation for transthoracic echocardiography in children with cyanotic and acyanotic congenital heart disease.

DESIGN

A prospective, nonrandomized study.

SETTING

A tertiary care teaching hospital.

PARTICIPANTS

Patients younger than 18 months with known or suspected congenital heart disease scheduled for transthoracic echocardiography with sedation.

INTERVENTIONS

Patients were divided into a cyanotic group (blood oxygen saturation <85%) or an acyanotic group (blood oxygen saturation ≥85%). This study used Dixon's up-and-down method sequential allocation design. In both groups, the initial dose of intranasal dexmedetomidine was 2 μg/kg and the gradient of increase or decrease was 0.25 μg/kg.

MEASUREMENTS AND MAIN RESULTS

The 50% effective dose (95% confidence interval) of intranasal dexmedetomidine sedation for transthoracic echocardiography was 3.2 (2.78-3.55) μg/kg and 1.9 (1.69-2.06) μg/kg in the cyanotic and acyanotic groups, respectively. None of the patients experienced significant adverse events.

CONCLUSION

The 50% (95% confidence intervals) effective doses of intranasal dexmedetomidine sedation for transthoracic echocardiography were 3.2 (2.78-3.55) μg/kg and 1.9 (1.69-2.06) μg/kg in children with cyanotic and acyanotic congenital heart disease, respectively.

Randomised Comparison between the Efficacy of Two Doses of Nebulised Dexmedetomidine for Premedication in Paediatric Patients

Objective

Nebulised dexmedetomidine can be an easy alternative for preoperative sedation in paediatric patients, but data regarding its efficacy are very limited.

Methods

This prospective, randomised, double-blind study included 66 patients aged between 1 and 8 years. Patients were divided into two groups as D2 and D3. The D2 group received 2 μg kg⁻¹ of nebulised dexmedetomidine, and the D3 group received 3 μg kg⁻¹ of nebulised dexmedetomidine preoperatively. All the patients received general anaesthesia and caudal epidural analgesia with 0.75 mL kg⁻¹ of 0.2% ropivacaine. Parental Separation Anxiety Scale at 30 min after the end of nebulisation, Mask Acceptance Score (MAS) during induction, haemodynamic variables, emergence agitation and duration of caudal analgesia were compared between the groups. Statistical analysis was done using Mann-Whitney U test and chi-square test. A p-value <0.05 was accepted as significant.

Results

All the parameters were comparable between the D2 and D3 groups; however, significantly more number of younger children was observed in the D3 group. Hence, further analysis was done after division into the lower age (1–3 years) and higher age (4–8 years) groups. In lower age group children, satisfactory parental separation was achieved in 100% of the patients in the D3 group compared to 20% of those in the D2 group (p=0.00). MAS was significantly better in the D3 group in both the lower (p=0.019) and higher (p=0.036) age groups.

Conclusion

We conclude that nebulised dexmedetomidine in a dose of 3 μg kg⁻¹ provides better parental separation and mask acceptance in younger children.

Safety and Efficacy of Buccal Dexmedetomidine for MRI Sedation in School-Aged Children

OBJECTIVES

Intranasal, intramuscular, and intravenous (IV) dexmedetomidine routes have been used successfully for pediatric MRI studies. We designed this retrospective study to determine efficacy and safety of buccal dexmedetomidine for pediatric MRI sedation.

METHODS

Medical records were reviewed of outpatient children ages 5 to 18 years who received buccal dexmedetomidine with or without oral midazolam for MRI sedation at a freestanding children's hospital sedation program in 2015 and 2016.

RESULTS

A total of 220 outpatient encounters received buccal dexmedetomidine for MRI. Mean age of the cohort was 10.1 ± 2.6 years (range: 5-18.7). Buccal dexmedetomidine dose administered was a mean of 2.20 ± 0.38 μg/kg (range: 0.88-3.19). Of the 220 sedation encounters, 179 (81.4%) patients had satisfactory sedation with buccal dexmedetomidine with or without oral midazolam: 84 had buccal dexmedetomidine as the sole sedative, 95 had satisfactory sedation when buccal dexmedetomidine and oral midazolam (mean: 0.33 ± 0.07 mg/kg; range: 0.21-0.53) were given together, 1 (0.4%) had satisfactory sedation when intranasal fentanyl and midazolam were administered in addition to buccal dexmedetomidine, and 35 (15.9%) required IV sedatives to achieve satisfactory sedation. All patients completed their MRI successfully except 5 (2.2%): 2 encounters were sedation failures, 2 IV sedations developed severe upper airway obstruction, and 1 IV sedation experienced MRI contrast anaphylaxis.

CONCLUSIONS

In a selected population of pediatric patients, buccal dexmedetomidine with or without midazolam provides adequate sedation for most MRI studies with few adverse effects, but given a failure rate of almost 20%, modifications to buccal dexmedetomidine dosing should be investigated.

Median effective dose of intranasal dexmedetomidine sedation for transthoracic echocardiography examination in postcardiac surgery and normal children: An up-and-down sequential allocation trial

BACKGROUND

Dexmedetomidine (DEX) has been used for sedation in young infants and children undergoing transthoracic echocardiography (TTE). The median effective dose of intranasal DEX has not been described for postcardiac surgery children. Postcardiac surgery children could require more DEX to achieve satisfactory sedation for TTE examination than children suspected of congenital heart disease.

OBJECTIVES

To study whether postcardiac surgery children need a larger dose of DEX for TTE than normal children.

DESIGN

A double-blind sequential allocation trial with doses determined by the Dixon and Massey up-and-down method.

SETTING

A tertiary care teaching hospital from 25 October to 30 November 2016.

PATIENTS

Children under the age of 3 years requiring intranasal DEX for TTE.

INTERVENTIONS

Children were allocated to a postcardiac surgery group (n = 20) or a normal group (n = 19). The first patient in both groups received intranasal DEX (2 μg kg): using the up-and-down method of Dixon and Massey, the next dose was dependent on the previous patient's response.

MAIN OUTCOME MEASURES

Median effective dose was estimated from the up-and-down method of Dixon and Massey and probit regression. A second objective was to study haemodynamic stability and adverse events with these doses.

RESULTS

The median effective dose (95% confidence interval) of intranasal DEX was higher in postcardiac surgery children than in normal children, 3.3 (2.72 to 3.78) μg kg versus 1.8 (1.71 to 2.04) (μg kg), respectively (P < 0.05). There were no significant differences in time to sedation, time to wake-up or TTE examination time between the two groups for successful sedation. Additionally, there were no significant adverse events.

CONCLUSION

The median effective dose of intranasal DEX for TTE sedation in postcardiac surgery children was higher than in normal children.

TRIAL REGISTRATION

chictr.org.cn identifier: ChiCTR-OOC-16009846.

Study of Feasibility and Safety of Higher-Dose Dexmedetomidine in Special Outpatient Examination of Pediatric Ophthalmology

Objective

To investigate the feasibility and safety of higher-dose dexmedetomidine in ophthalmological outpatient examination of children with cataract.

Methods

100 cases of children were recruited in the study and randomly equally divided into two groups. One group was given 2 μg/kg intranasal dexmedetomidine anesthesia, while the other group was under 3 μg/kg. The dosage of dexmedetomidine was calculated by the same anesthesiologist according to the weight of patient. After sufficient sedation, the same ophthalmologist performed ocular examinations manually, including intraocular pressure, keratometry, axial length, and corneal thickness and recorded the ocular position score during intraocular pressure measurement and corneal thickness measurement. Other variables were sedation onset time, recovery time, vital signs, and side effects.

Results

In intraocular pressure measurement, only one case in the 2 μg/kg group did not complete the examination, while all cases in the 3 μg/kg group completed the examination and the difference of the success rate between the two groups was nonsignificant (P > 0.05). The success rates of the 3 μg/kg group in corneal curvature, axial length, and corneal thickness examination were 96%, 92%, and 86%, respectively, which were significantly higher than those of the 2 μg/kg group (22%, 18%, and 4%). The average onset time of sedation in the 3 μg/kg group was 15.42 ± 2.09 minutes, which was significantly shorter than that in the 2 μg/kg group (19.52 ± 2.43 minutes, P < 0.001). The average time of completing all examinations in the 3 μg/kg group was 18.36 ± 4.01 minutes, which was significantly shorter than that in the 2 μg/kg group (22.62 ± 4.13 min, P < 0.001). The recovery time of group 3 μg/kg was 90.62 ± 27.80 min, which was significantly longer than that of group 2 μg/kg (49.20 ± 15.50 min). Vital signs such as pulse, blood pressure, oxygen saturation, and heart rate kept in normal range throughout the tests, and no obvious side effects were observed.

Conclusion

3 μg/kg intranasal dexmedetomidine had a higher sedation success rate and quality than 2 μg/kg did in pediatric ocular examinations, without any obvious side effects.

A randomized controlled trial of oral chloral hydrate vs intranasal dexmedetomidine plus buccal midazolam for auditory brainstem response testing in children

BACKGROUND

Moderate to deep sedation is required for an auditory brainstem response test when high-intensity stimulation is used. Chloral hydrate is the most commonly used sedative, whereas intranasal dexmedetomidine is increasingly used in pediatric non-painful procedural sedations.

OBJECTIVE

The aim of this study was to compare the sedation success rate after oral chloral hydrate at 50 mg kg^-1 and intranasal dexmedetomidine at 3 μg kg^-1 plus buccal midazolam at 0.1 mg kg^-1 for an auditory brainstem response test.

METHODS

Children who required an auditory brainstem response test were recruited and randomly assigned to receive oral chloral hydrate at 50 mg kg^-1 and intranasal placebo, or intranasal dexmedetomidine at 3 μg kg^-1 with buccal midazolam 0.1 mg kg^-1 . The primary outcome was the rate of successful sedation for auditory brainstem response tests.

RESULTS

Fifty-seven out of 82 (69.5%) were successfully sedated after chloral hydrate, while 70 out of 78 (89.7%) children were successfully sedated with dexmedetomidine plus midazolam combination, with the odd ratio (95% CI) for successful sedation between dexmedetomidine plus midazolam combination and chloral hydrate estimated to be 3.84 (1.61-9.16), P = 0.002. Dexmedetomidine plus midazolam was associated with quicker onset with median onset time 15 (IQR 11.0-19.8) for dexmedetomidine plus midazolam and 20 (IQR 15.0-27.0) for chloral hydrate respectively, with difference between median (95% CI) of 5 [3-8], P < 0.0001). The behavior observed during drug administration of intranasal dexmedetomidine and buccal midazolam was better that of the children who had oral chloral hydrate. No children required oxygen therapy or medical intervention for hemodynamic disturbances in this study and the incidence of hypotension and bradycardia was similar.

CONCLUSION

Intranasal dexmedetomidine plus buccal midazolam was associated with higher sedation success with deeper level of sedation, with similar discharge time and adverse event rate when compared to chloral hydrate.

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.

Use of Intranasal Dexmedetomidine as a Solo Sedative for MRI of Infants

BACKGROUND

Dexmedetomidine, a selective α-2 receptor agonist, can be delivered via the intranasal (IN) route and be used for procedural sedation. The drug's favorable hemodynamic profile and relative ease of application make it a promising agent for sedation during radiologic procedures, although there are few studies on its efficacy for MRI studies.

METHODS

A retrospective chart review was performed between June 2014 and December 2016. Outpatients between 1 and 12 months of age who received 4 μg/kg of IN dexmedetomidine for MRI were included in the analysis. Our aim with this study was to determine the rate of successful completion of the sedation procedure without the need for a rescue drug (other than repeat IN dexmedetomidine).

RESULTS

A total of 52 subjects were included in our study. Median (interquartile range) patient age was 7 (5-8) months. Median (interquartile range) procedure length was 40 (35-50) minutes. Overall success rate (including first dose and any rescue dose IN) of dexmedetomidine was 96.2%. None of the patients had significant adverse effects related to dexmedetomidine.

CONCLUSIONS

IN dexmedetomidine is an effective solo sedative agent for MRI in infants.

A multinational, drug utilization study to investigate the use of dexmedetomidine (Dexdor®) in clinical practice in the EU

Aims

Dexmedetomidine (dexdor®) is approved in the European Union (EU) for sedation of adults in the intensive care unit (ICU). The present observational, retrospective study was requested by the European Medicines Agency to investigate dexmedetomidine use in clinical practice, with a particular focus on off‐label use, including the paediatric population.

Methods

Study countries and sites were chosen from those with highest dexmedetomidine use, based on sales. Site selection (blind) was conducted by a multispecialist, independent group. Anonymized data on demographics, treatment indication, dexmedetomidine dosing, concomitant medications and treatment effectiveness were collected retrospectively from records of all dexmedetomidine‐treated patients at the site during the enrolment period. Informed consent was waived, to avoid influencing the prescribing of dexmedetomidine. Recruitment was completed within 18 months of first site initiation.

Results

Data from 2000 patients were collected from 16 hospitals in four EU countries (Finland 750, Poland 505, Germany 470, Austria 275). The median age was 62 years, with more males (70.2%) than females. Dexmedetomidine was primarily used in the adult ICU (86.0%) for ICU sedation (78.6%) and mostly dosed according the product label. The intended sedative effect was obtained in 84.9% of administrations. Paediatric use (5.9% of patients, mostly in Austria and Finland) occurred mainly in the adult or paediatric ICU (75.6%) for sedation (67.2%).

Conclusions

Overall, most patients were treated with dexmedetomidine according to the product labelling. Use in children was limited but significant and similar in scope to that in adults. Administrations not fully according to the product labelling usually occurred in an ICU environment and reflected extensively investigated clinical uses of dexmedetomidine.