Median effective dose of intranasal dexmedetomidine sedation for transthoracic echocardiography in pediatric patients with noncyanotic congenital heart disease: An up-and-down sequential allocation trial

Combined sedation in pediatric magnetic resonance imaging: determination of median effective dose of intranasal dexmedetomidine combined with oral midazolam

BACKGROUND

The exact median effective dose (ED50) of intranasal dexmedetomidine combined with oral midazolam sedation for magnetic resonance imaging (MRI) examination in children remains unknow and the aim of this study was to determine the ED50 of their combination.

METHODS

This is a prospective dose-finding study. A total of 53 children aged from 2 months to 6 years scheduled for MRI examination from February 2023 to April 2023 were randomly divided into group D (to determine the ED50 of intranasal dexmedetomidine) and group M (to determine the ED50 of oral midazolam). The dosage of dexmedetomidine and midazolam was adjusted according to the modified Dixon's up-and-down method, and the ED50 was calculated with a probit regression approach.

RESULTS

The ED50 of intranasal dexmedetomidine when combined with 0.5 mg∙kg- 1 oral midazolam was 0.39 µg∙kg- 1 [95% confidence interval (CI) 0.30 to 0.46 µg∙kg- 1] while the ED50 of oral midazolam was 0.17 mg∙kg- 1 (95% CI 0.01 to 0.29 mg∙kg- 1) when combined with 1 µg∙kg- 1 intranasal dexmedetomidine. The sedation onset time of children with successful sedation in group D was longer than in group M (30.0[25.0, 38.0]vs 19.5[15.0, 35.0] min, P < 0.05). No other adverse effects were observed in the day and 24 h after medication except one dysphoria.

CONCLUSION

This drug combination sedation regimen appears suitable for children scheduled for MRI examinations, offering a more precise approach to guide the clinical use of sedative drugs in children.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, identifier: ChiCTR2300068611(24/02/2023).

Median effective dose of intranasal dexmedetomidine for satisfactory mask induction in children undergoing examination under anaesthesia for retinoblastoma - A prospective up and down sequential allocation study

Background and Aims

Inhalational technique is used to induce anaesthesia in children without intravenous access. We aimed to determine the median effective dose (ED50) of intranasal dexmedetomidine to ensure satisfactory mask acceptance during inhalation induction in children with retinoblastoma undergoing examination under anaesthesia.

Methods

A prospective sequential allocation study was conducted in children aged 1-60 months divided into Group A (1-18 months) and Group B (18-60 months). Children were administered dexmedetomidine intranasally as premedication. Sedation was assessed using the modified Observer Assessment of Alertness and Sedation Scale until induction. Successful mask acceptance was defined as a cooperative or asleep child during inhalational induction. The starting dose of dexmedetomidine was 1 µg/kg. The next dose varied by 0.2 µg/kg depending on the outcome of this case. According to the Dixon up-and-down method, the mean of midpoints of the failure-success sequence was calculated to obtain the ED50 values.

Results

The ED50 of intranasal dexmedetomidine for satisfactory mask acceptance was 0.7 µg/kg (95% confidence interval [CI]: 0.54-0.86) in Group A (n = 23) and 0.96 µg/kg (95% CI: 0.83-1.08) in Group B (n = 25) (P = 0.020). The mean (standard deviation) duration of anaesthesia was 33.5 (14.9) minutes in group A versus 23.5 (8.48) minutes in Group B (P = 0.007).

Conclusion

ED50 was lower in children younger than 18 months than in older children. There was no difference in the time to discharge from the post-anaesthesia care unit despite the procedure being longer in smaller children.

Clinical Use of Adrenergic Receptor Ligands in Acute Care Settings

In this chapter, we review how ligands, both agonists and antagonists, for the major classes of adrenoreceptors, are utilized in acute care clinical settings. Adrenergic ligands exert their effects by interacting with the three major classes of adrenoceptors. Adrenoceptor agonists and antagonists have important applications, ranging from treatment of hypotension to asthma, and have proven to be extremely useful in a variety of clinical settings of acute care from the operating room to the critical care environment. Continued research interpreting the mechanisms of adrenoreceptors may help the discovery of new drugs with more desirable clinical profiles.

Predictors of pediatric sedation failure with initial dose of intranasal dexmedetomidine and oral midazolam

BACKGROUND

To assess the sedative failure rate over different dose combinations of intranasal dexmedetomidine and oral midazolam for procedural sedation.

METHODS

This was a retrospective study. Four groups were established according to the initial dose of sedatives. The primary outcome was the sedative failure rate for different doses of the two-drug combination. The risk factors associated with sedation failure were analyzed.

RESULTS

A total of 2165 patients were included in the final analysis. Of these, 394 children were classified as sedation failure after the initial dose of a combination of intranasal dexmedetomidine and oral midazolam. Although the initial doses of intranasal dexmedetomidine and oral midazolam administered to patients varied widely, no significant differences were detected in the sedation outcomes among the groups. Multivariate analysis showed that sedation history, a history of sedation failure, and echocardiography were independent risk factors for sedation failure after an initial dose of intranasal dexmedetomidine and oral midazolam. In contrast, patients undergoing lung function and MRI were more likely to be successfully sedated.

CONCLUSION

A combination of low-dose intranasal dexmedetomidine and oral midazolam provides adequate sedation efficacy without any increase in side effects, especially for patients undergoing MRI or lung function examination.

IMPACT

This is an original article about the risk factors of sedation failure with an initial dose of intranasal dexmedetomidine and oral midazolam for procedure sedation. For patients undergoing echocardiogram, it is better to choose other sedatives, while a combination of intranasal dexmedetomidine and oral midazolam is a good option for patients undergoing MRI or lung function. The selection of sedative drugs should be personalized according to different procedures.

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.

The use of dexmedetomidine in the emergency department: A systematic review

BACKGROUND

Dexmedetomidine (DEX), a centrally acting alpha-2 agonist, is increasingly used for sedation in multiple clinical settings. Evidence from the intensive care unit and operative settings suggests DEX may have significant advantages over traditional GABAergic sedatives such as benzodiazepines. There has been limited research on the use of DEX in the emergency department (ED).

METHODS

We performed a systematic review of the medical literature to identify all published evidence regarding the use of DEX in the ED. We included randomized and nonrandomized studies and studies reporting any use of DEX in the ED, even when it was not the primary focus of the study. Two authors reviewed studies for inclusion, and a single author assessed studies for quality and risk of bias and abstracted data.

RESULTS

We identified 35 studies meeting inclusion criteria, including 11 randomized controlled trials, 13 cohort and other nonrandomized studies, and 11 case reports and case series. Significant heterogeneity in interventions, comparators, indications, and outcomes precluded data pooling and meta-analysis. We found modest evidence that DEX was efficacious in facilitating medical imaging and mixed and limited evidence regarding its efficacy for procedural sedation and sedation of nonintubated medical and psychiatric patients. Our results suggested that DEX is associated with bradycardia and hypotension, which are generally transient and infrequently require medical intervention.

CONCLUSIONS

A limited body of generally poor- to moderate-quality evidence suggests that the use of DEX may be efficacious in certain clinical scenarios in the ED and that DEX use in the ED is likely safe. Further high-quality research into DEX use in the ED setting is needed, with a particular focus on clear and consistent selection of indications, identification of clear and clinically relevant primary outcomes, and careful assessment of the clinical implications of the hemodynamic effects of DEX therapy.

Dose Escalation Pharmacokinetic Study of Intranasal Atomized Dexmedetomidine in Pediatric Patients With Congenital Heart Disease

BACKGROUND

Atomized intranasal dexmedetomidine is an attractive option when sedation is required for pediatric patients as either premedication or the sole agent for noninvasive, nonpainful procedures. While intranasal dexmedetomidine is used frequently in this population, it is still unclear what dose and time of administration relative to the procedure will result in the optimal effect. Knowledge regarding the maximum concentration (C max ) and time to reach maximum concentration (T max ) of intranasally administered dexmedetomidine is the first step toward this. The risk of hemodynamic instability caused by increasing doses of dexmedetomidine necessitates a greater understanding of the pharmacokinetics in children.

METHODS

Sixteen pediatric patients 2 to 6 years of age undergoing elective cardiac catheterization received 2 or 4 μg/kg dexmedetomidine intranasally. Plasma concentrations were determined by liquid chromatography-tandem mass spectrometry with a validated assay. Descriptive noncompartmental analysis provided estimates of peak concentrations and time to reach peak concentrations. A population pharmacokinetic model was developed using nonlinear mixed-effects modeling. Simulations were performed using the final model to assess dose concentrations with an alternative dosing regimen of 3 µg/kg.

RESULTS

A median peak plasma concentration of 413 pg/mL was achieved 91 minutes after 2 μg/kg dosing, and a median peak plasma concentration of 1000 pg/mL was achieved 54 minutes after 4 μg/kg dosing. A 1-compartment pharmacokinetic model adequately described the data. Three subjects in the 4 μg/kg dosing cohort achieved a dose-limiting toxicity (DLT), defined as a plasma dexmedetomidine concentration >1000 pg/mL. None of these subjects had any significant hemodynamic consequences. Simulations showed that no subjects would experience a level >1000 pg/mL when using a dose of 3 µg/kg.

CONCLUSIONS

Concentrations associated with adequate sedation can be achieved with intranasal dexmedetomidine doses of 2 to 4 µg/kg in children 2 to 6 years of age. However, 50% of our evaluable subjects in this cohort reached a plasma concentration >1000 pg/mL. Doses of 3 µg/kg may be optimal in this population, with simulated concentrations remaining below this previously established toxicity threshold. Further studies correlating concentrations with efficacy and adverse effects are needed.

Preoperative sedation in children with congenital heart disease: 50% and 95% effective doses, hemodynamic effects, and safety of intranasal dexmedetomidine

STUDY OBJECTIVE

To determine the 50% and 95% effective doses (ED50 and ED95, respectively), hemodynamic effects, and safety of intranasal dexmedetomidine for preoperative sedation in pediatric patients with congenital heart disease (CHD) with a left-to-right shunt.

DESIGN

Double-blind sequential allocation trial.

SETTING

Pediatric preoperative waiting area.

PATIENTS

86 pediatric patients ASA physical status II-III scheduled for cardiac surgery, aged1-month to 6-years-old with left-to-right type CHD.

INTERVENTIONS

Children were divided into three groups according to age: infants (1 month-1 year), toddlers (1-3 years), and preschoolers (3-6 years). The first patient in all groups received intranasal dexmedetomidine (2 μg/kg), using the up-and-down Dixon method, and the and the next patient's dose was dependent on the previous patient's response.

MEASUREMENTS

Assessment using the Modified Observer's Assessment of Alertness/Sedation Scale and the Mask Acceptance Scale was performed before and every 5 min after treatment. Pulse oxygen saturation and heart rate were recorded at baseline, at 10-min intervals, and after admission to the operating room. Systolic pulmonary artery pressure was measured before anesthesia induction.

MAIN RESULTS

The respective ED₅₀ (95% confidence interval [CI]) and ED₉₅ (95% CI) values for preoperative sedation using intranasally administered dexmedetomidine were 3.1 (2.8-3.3) and 3.5 (3.3-4.0) μg/kg for infants; 3.4 (3.2-3.6) and 3.9 (3.7-4.4) μg/kg for toddlers; and 2.4 (2.2-2.6) and 2.9 (2.6-3.3) μg/kg for preschoolers. ED₅₀ was lower for preschoolers than for toddlers (p < 0.001) and infants (p = 0.044). No obvious difference in ED50 was found between infants and toddlers. There was no significant difference in sedation onset time among the groups, and no adverse events were observed during sedation in all patients.

CONCLUSIONS

Intranasal dexmedetomidine can be safety used for preoperative sedation in children with CHD and is effective for sedation when dosed appropriately. Trial registrationclinicaltrials.gov (ChiCTR2100047472); registered 20 June 2021.

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.

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.

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.

Pharmacokinetics and Sedative Effects of Intranasal Dexmedetomidine in Ambulatory Pediatric Patients

BACKGROUND

Our aim was to characterize the pharmacokinetics and sedative effects of intranasally (IN) administered dexmedetomidine used as an adjuvant in pediatric patients scheduled for magnetic resonance imaging (MRI) requiring sedation.

METHODS

This was an open-label, single-period study without randomization. Pediatric patients from 5 months to 11 years of age scheduled for MRI and receiving IN dexmedetomidine for premedication as part of their care were included in this clinical trial. Single doses of 2-3 µg·kg of dexmedetomidine were applied IN approximately 1 hour before MRI. Five or 6 venous blood samples were collected over 4 hours for dexmedetomidine concentration analysis. Sedation was monitored with Comfort-B scores, and vital signs were recorded. Pharmacokinetic variables were calculated with noncompartmental methods and compared between 3 age groups (between 1 and 24 months, from 24 months to 6 years, and over 6-11 years).

RESULTS

We evaluated 187 consecutive patients for suitability, of which 132 were excluded. Remaining 55 patients were recruited, of which 5 were excluded before the analysis. Data from 50 patients were analyzed. The average (standard deviation [SD]) dose-corrected peak plasma concentration (Cmax) was 0.011 liter (0.0051), and the median (interquartile range [IQR]) time to reach peak concentration (tmax) was 37 minutes (30-45 minutes). There was negative correlation with Cmax versus age (r = -0.58; 95% confidence interval [CI], -0.74 to -0.37; P < .001), but not with tmax (r = -0.14; 95% CI, 0.14-0.39; P = .35). Dose-corrected areas under the concentration-time curve were negatively correlated with age (r = -0.53; 95% CI, 0.70 to -0.29; P < .001). Median (IQR) maximal reduction in Comfort-B sedation scores was 8 (6-9), which was achieved 45 minutes (40-48 minutes) after dosing. Median (IQR) decrease in heart rate was 15% (9%-23%) from the baseline.

CONCLUSIONS

Dexmedetomidine is relatively rapidly absorbed after IN administration and provides clinically meaningful but short-lasting sedation in pediatric patients.

Incidence and risk factors of bradycardia in pediatric patients undergoing intranasal dexmedetomidine sedation

BACKGROUND

Dexmedetomidine is widely used for non-invasive pediatric procedural sedation. However, the hemodynamic effects of intravenous dexmedetomidine are a concern. There has been a growing interest in the application of intranasal dexmedetomidine as a sedative in children.

OBJECTIVE

To investigate the incidence of bradycardia in children undergoing intranasal dexmedetomidine sedation and to identify the associated risk factors.

METHODS

Data pertaining to pediatric patients who underwent intranasal dexmedetomidine sedation for non-invasive investigations at the Kunming Children's Hospital between October 2017 and August 2018 were retrospectively analyzed.

RESULTS

Out of 9984 children who qualified for inclusion, 228 children (2.3%) developed bradycardia. The incidence of bradycardia in the group that received additional dose of dexmedetomidine was higher than that in the group that did not receive additional dose (9.2% vs 16.7%; P = .003). The incidence of bradycardia in males was higher than that in females (2.6% vs 1.8%; P = .007). On multivariate logistic regression, only male gender showed an independent association with the occurrence of bradycardia (odds ratio 1.48; 95% confidence interval 1.11-1.97; P = .008).

CONCLUSIONS

The overall incidence of bradycardia in children after sole use of intranasal dexmedetomidine sedation was 2.3%. Male children showed a 1.48-fold higher risk of bradycardia. However, the blood pressure of the children who developed bradycardia was within the normal range. Simple wake-up can effectively manage bradycardia induced by intranasal dexmedetomidine sedation.

Intranasal dexmedetomidine is an effective sedative agent for electroencephalography in children

BACKGROUND

Intranasal dexmedetomidine (DEX), as a novel sedation method, has been used in many clinical examinations of infants and children. However, the safety and efficacy of this method for electroencephalography (EEG) in children is limited. In this study, we performed a large-scale clinical case analysis of patients who received this sedation method. The purpose of this study was to evaluate the safety and efficacy of intranasal DEX for sedation in children during EEG.

METHODS

This was a retrospective study. The inclusion criteria were children who underwent EEG from October 2016 to October 2018 at the Children's Hospital affiliated with Chongqing Medical University. All the children received 2.5 μg·kg^- 1 of intranasal DEX for sedation during the procedure. We used the Modified Observer Assessment of Alertness/Sedation Scale (MOAA/S) and the Modified Aldrete score (MAS) to evaluate the effects of the treatment on sedation and resuscitation. The sex, age, weight, American Society of Anesthesiologists physical status (ASAPS), vital signs, sedation onset and recovery times, sedation success rate, and adverse patient events were recorded.

RESULTS

A total of 3475 cases were collected and analysed in this study. The success rate of the initial dose was 87.0% (3024/3475 cases), and the success rate of intranasal sedation rescue was 60.8% (274/451 cases). The median sedation onset time was 19 mins (IQR: 17-22 min), and the sedation recovery time was 41 mins (IQR: 36-47 min). The total incidence of adverse events was 0.95% (33/3475 cases), and no serious adverse events occurred.

CONCLUSIONS

Intranasal DEX (2.5 μg·kg^- 1) can be safely and effectively used for EEG sedation in children.

The 95% effective dose of intranasal dexmedetomidine sedation for pulmonary function testing in children aged 1-3 years: A biased coin design up-and-down sequential method

STUDY OBJECTIVE

Intranasal dexmedetomidine (DEX) can provide adequate sedation during short examinations in children. However, we found no data regarding the 95% effective dose (ED₉₅) of intranasal DEX for children's pulmonary function testing (PFT).

DESIGN

Prospective study and a biased coin design up-and-down sequential method.

SETTING

Sedation center of Children's Hospital of Chongqing Medical University.

PATIENTS

Children aged 1-3 years undergoing pulmonary function testing.

INTERVENTION

The dose of DEX for each subsequent patient was determined by the response of the previous patient with the biased coin design up-and-down sequential method with an interval of 0.25 μg∙kg^-1.

MEASUREMENTS

Children aged 1-3 years who received pulmonary function testing were involved in this dose-finding trial. Intranasal DEX started at a dose of 2 μg∙kg^-1 on the first patient. The dose of DEX for each subsequent patient was determined by the response of the previous patient with the biased coin design up-and-down sequential method with an interval of 0.25 μg∙kg^-1. The sedation was assessed by the Modified Observer Assessment of Alertness and Sedation (MOAA/S) scale, and recovery was assessed by the modified Aldrete recovery score. The ED₉₅ was calculated using isotonic regression. Other variables, including the sedation onset time, examination time, wake-up time, blood pressure (BP), heart rate (HR), respiratory rate (RR), and oxyhaemoglobin desaturation (SpO₂), were recorded. Adverse events such as hypotension, bradycardia, respiration depression, oxyhaemoglobin desaturation, regurgitation and vomiting were recorded.

MAIN RESULTS

A total of 68 children were enrolled for the study; 62 children had successful sedation, and 6 had failed sedation. The ED₉₅ of intranasal DEX was estimated to be 2.64 μg∙kg^-1 [95% confidence interval (CI), 2.49-2.87 μg∙kg^-1]. The sedation onset time for all patients was 15.0 (12.3-19.0) min. The sedation onset time of successful sedation patients was 15.0 (12.0-19.0) min, the sedation onset time of failed sedation patients was 16.0 (15.0-27.8) min, the examination time was 8 (7-10) min, and the wake-up time was 40 (35-43) min. There were no adverse events during the whole procedure.

CONCLUSION

The ED₉₅ of intranasal DEX sedation in children aged 1-3 years undergoing PFT was 2.64 μg∙kg^-1.

Comparison of intranasal midazolam, intranasal ketamine, and oral chloral hydrate for conscious sedation during paediatric echocardiography: results of a prospective randomised study

OBJECTIVE

There are several agents used for conscious sedation by various routes in children. The aim of this prospective randomised study is to compare the effectiveness of three commonly used sedatives: intranasal ketamine, intranasal midazolam, and oral chloral hydrate for children undergoing transthoracic echocardiography.

METHODS

Children who were referred to paediatric cardiology due to a heart murmur for transthoracic echocardiography were prospectively randomised into three groups. Seventy-three children received intranasal midazolam (0.2 mg/kg), 72 children received intranasal ketamine (4 mg/kg), and 72 children received oral chloral hydrate (50 mg/kg) for conscious sedation. The effects of three agents were evaluated in terms of intensity, onset, and duration of sedation. Obtaining high-quality transthoracic echocardiography images (i.e. absence of artefacts) were regarded as successful sedation. Side effects due to medications were also noted.

RESULTS

There was no statistical difference in terms of sedation success rates between three groups (95.9, 95.9, and 94.5%, respectively). The median onset of sedation in the midazolam, ketamine, and chloral hydrate was 14 minutes (range 7-65), 34 minutes (range 12-56), and 40 minutes (range 25-57), respectively (p < 0.001 for all). However, the median duration of sedation in study groups was 68 minutes (range 20-75), 55 minutes (range 25-75), and 61 minutes (range 34-78), respectively (p = 0.023, 0.712, and 0.045). Gastrointestinal side effects such as nausea and vomiting were significantly higher in the chloral hydrate group (11.7 versus 0% for midazolam and 2.8% for ketamine, respectively, p = 0.002).

CONCLUSION

Results of our prospectively randomised study indicate that all three agents provide adequate sedation for successful transthoracic echocardiography. When compared the three sedatives, intranasal midazolam has a more rapid onset of sedation while intranasal ketamine has a shorter duration of sedation. Intranasal ketamine can be used safely with fewer side effects in children undergoing transthoracic echocardiography.

Determination of the 90% effective dose of intranasal dexmedetomidine for sedation during electroencephalography in children

BACKGROUND

The intranasal route of dexmedetomidine (DEX) administration is becoming increasingly popular for providing adequate sedation during short examinations in infants and children. However, data on the 90% effective dose (ED90) of intranasal DEX are rare in children under 3 years old.

METHODS

This is a double-blind trial using a biased coin design up-and-down sequential method (BCD-UDM). Fifty-three children aged under 3 years old requiring DEX for EEG were included in our study. The first patient received 2.5 μg kg^-1 DEX, and the dose of DEX administered to the subsequent patient was determined by the response of the previous patient. The patient responses were recorded and analysed to calculate the ED90 by isotonic regression. The 95% confidence interval (CI) was estimated using a bootstrapping method.

RESULTS

Fifty-three patients were included in our study, of which 45 patients were successfully sedated, and the 8 instances of failed sedation were rescued using sevoflurane inhalation, allowing the completion of the procedure. The 90% effective dose of DEX was calculated to be 3.28 µg kg^-1 , and the 95% CI was 2.74 ~ 3.39 µg kg^-1 . No significant adverse events occurred in any of the patients.

CONCLUSION

The 90% effective dose of intranasal DEX sedation for EEG was 3.28 μg kg^-1 in children under 3 years old.

Median Effective Dose of Intranasal Dexmedetomidine for Transthoracic Echocardiography in Children with Kawasaki Disease Who Have a History of Repeated Sedation

Background

The aim of this study was to investigate the median effective dose (ED50) of intranasal dexmedetomidine for echocardiography in children with Kawasaki disease who had a history of repeated sedation.

Material/Methods

There were 73 pediatric Kawasaki disease patients aged 1 to 36 months enrolled in this study who had American Society of Anesthesiologists (ASA) I–II, were scheduled to undergo echocardiography under sedation. They were assigned to 2 groups (group A: age 1–18 months, and group B: age 19–36 months). Intranasal dexmedetomidine was administered before echocardiography. The dose of intranasal dexmedetomidine was determined with the up-down sequential allocation, and the initial dose was 2 μg/kg with an increment/decrement of 0.2 μg/kg. The ED50 of intranasal dexmedetomidine for sedation was determined with the up-and-down method of Dixon and Massey and probit regression. The time to effective sedation, time to regaining consciousness, vital signs, oxygen saturation, echocardiographic examination time, clinical side-effects, and characteristics of regaining consciousness were recorded and compared.

Results

The ED50 of intranasal dexmedetomidine for sedation was 2.184 μg/kg (95% CI, 1.587–2.785) in group A and 2.313 μg/kg (95% CI, 1.799–3.426) in group B. There were no significant differences in the time to sedation and time to regaining consciousness between groups. Additionally, change in hemodynamic and hypoxemia were not noted in both groups.

Conclusions

The ED50 of intranasal dexmedetomidine was determined in children with Kawasaki disease who had a history of repeated sedation to be appropriate for repeated-routine sedation of echocardiographic examination in pediatric patients. The ED50 of intranasal dexmedetomidine for echocardiography in this circumstance is similar to that in children receiving initial sedation.

Is Orally Administered Pentobarbital a Safe and Effective Alternative to Chloral Hydrate for Pediatric Procedural Sedation?

OBJECTIVES

Chloral hydrate had been extensively used for children undergoing sedation for imaging studies, but after the manufacturer discontinued production, pediatric sedation providers explored alternative sedation medications. Those medications needed to be at least as safe and as effective as chloral hydrate. In this study, we examined if pentobarbital is a suitable replacement for chloral hydrate.

METHODS

Subjects who received pentobarbital were recruited from a prospectively collected database, whereas we used a retrospective chart review to study subjects who received chloral hydrate. Sedation success was defined as the ability to provide adequate sedation using a single medication. We included electively performed sedations for subjects aged 2 months to 3 years who received either pentobarbital or chloral hydrate orally. We excluded subjects stratified as American Academy of Anesthesiologists category III or higher and those who received sedation for electroencephalogram. The data collected captured subject demographics and complications.

RESULTS

Five hundred thirty-four subjects were included in the final analysis, 368 in the chloral hydrate group and 166 in the pentobarbital group. Subjects who received pentobarbital had a statistically significant higher success rate [136 (82%) vs 238 (65%), p < 0.001], but longer sleeping time (18.1% vs 0%, p < 0.001) in all age groups. Subjects who received chloral hydrate had a higher risk of airway complications in the <1 year of age group (6.5% vs 1.8%, p = 0.03).

CONCLUSIONS

For pediatric patients younger than 3 years of age undergoing sedation for imaging studies, oral pentobarbital may be at least as effective and as safe as chloral hydrate, making it an acceptable and practical alternative.

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.