Comparison of sedation by intranasal dexmedetomidine and oral chloral hydrate for pediatric ophthalmic examination

Efficacy and Safety of Dexmedetomidine Compared to Other Needle-Free Pharmacological Sedation Methods in Pediatric Patients Undergoing Imaging Procedures

BACKGROUND

Pediatric patients often require sedation during magnetic resonance imaging (MRI) and computed tomography (CT) to ensure stillness and minimize stress. This meta-analysis compared the effectiveness and safety of 3 sedative agents-dexmedetomidine, midazolam, and chloral hydrate-for pediatric MRI/CT sedation.

METHODS

Six studies with a total of 633 patients were included in the analysis. Quality assessment revealed varying levels of bias risk. Dexmedetomidine exhibited a significantly higher successful sedation rate compared to midazolam (risk ratio [RR] = 0.43, 95% confidence interval [CI] [0.29-0.64]), but no statistically significant difference compared to chloral hydrate (RR = 0.94, 95% CI [0.60-1.45]). Chloral hydrate also showed a higher successful sedation rate compared to midazolam (RR = 0.46, 95% CI [0.25-0.83]). The onset of sedation time did not significantly differ between the 3 agents.

RESULTS

The dexmedetomidine group had a significantly higher incidence of bradycardia compared to the chloral hydrate group (RR = 0.17, 95% CI [0.05-0.59]), but no significant difference compared to the midazolam group (RR = 0.29, 95% CI [0.06-1.26]). No statistically significant differences were observed in the incidence of nausea and vomiting between the 3 groups.

CONCLUSIONS

Dexmedetomidine demonstrates effectiveness in pediatric MRI/CT sedation, offering advantages over midazolam and similar efficacy to chloral hydrate. Careful cardiovascular monitoring is essential during administration, particularly in patients with congenital heart disease. Sublingual and intranasal administration of dexmedetomidine is a viable option with high bioavailability. This meta-analysis contributes valuable insights into refining sedation protocols for pediatric imaging procedures, emphasizing efficacy and safety considerations.

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/.

Two-center randomized controlled trial comparing oral chloral hydrate and intranasal combination of dexmedetomidine and ketamine for procedural sedation in children: study protocol

BACKGROUND

Oral chloral hydrate is widely used in pediatric sedation. Intranasal dexmedetomidine has been increasingly used for pediatric sedation; however, its improvement is warranted. The combination of dexmedetomidine with ketamine can improve onset and hemodynamic stability while maintaining sedative efficacy. This study aims to determine the efficacy and safety of intranasal combination of dexmedetomidine and ketamine compared to oral chloral hydrate.

METHODS

This is a prospective, parallel-arm, single-blinded, two-center, superiority randomized controlled trial with 1:1 allocation, designed to compare the effects of intranasal combination of dexmedetomidine and ketamine with those of oral chloral hydrate. We shall enroll 136 patients aged < 7 years old in this study. Prior to the procedure, we shall randomize each patient into the control group (oral chloral hydrate 50 mg/kg) or study group (intranasal dexmedetomidine 2 μg/kg and ketamine 3 mg/kg). The primary outcome will be the rate of achieving an adequate sedation level (6-point Pediatric Sedation State Scale 1, 2, or 3) within 15 min. In addition, we shall measure the sedation time, sedation failure rate, completion of procedure, adverse events, patient acceptance, and physician satisfaction.

DISCUSSION

This study will provide evidence of the efficacy and safety of the intranasal combination of dexmedetomidine and ketamine in comparison with oral chloral hydrate.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT04820205. Registered on 19th March 2021.

Procedural sedation in children for fractionated radiation treatment: Intranasal dexmedetomidine versus oral midazolam and ketamine

BACKGROUND AND AIMS

Sedation in paediatric cancer for fractionated radiation treatment (RT) is unique as the child has to be still for accurate delivery of RT, monitoring of the child is from a remote location and sedation is repeated for multiple sessions of RT. The present study was undertaken to compare the efficacy of intranasal dexmedetomidine with oral midazolam and ketamine combination for repeated sedation during fractionated RT in paediatric oncology.

METHODS

Ninety children aged between 3-6 years, planned for 21 fractions of RT, were randomised to receive intranasal dexmedetomidine 2 μg/kg (group D) or oral midazolam 0.2 mg/kg and ketamine 5 mg/kg (group MK). The 21 sessions of fractionated radiotherapy were divided into three subgroups of seven consecutive exposures 1-7, 8-14 and 15-21 for comparison. The primary endpoint was to determine the incidence of successful sedation. The sedation score achieved, time to satisfactory sedation and discharge, rescue ketamine required, and side effects were secondary endpoints.

RESULTS

The incidence of successful sedation in the three successive RT subgroups; sessions: 1-7, 8-14 and 15-21, was 82%, 75.6% and 66.7% in group D, as compared to 40%, 24.4% and 13.3% in group MK, respectively. (P < 0.001). A decrease in successful sedation was noted in the successive subgroups. Time to successful sedation and discharge was earlier in group D in comparison to MK (P = 0.000). More patients in group MK required rescue ketamine (P = 000).

CONCLUSION

Intranasal dexmedetomidine produces more satisfactory sedation as compared to oral ketamine with midazolam for fractionated RT.

Use of a single dose of 70mg/kg chloral hydrate as a hypnotic in nuclear magnetic resonance. A prospective study of 3132 cases

OBJECTIVE

To assess the mean time to hypnosis, hemodynamic stability, and incidence of complications associated with the administration of 70mg/kg oral chloral hydrate in children scheduled for magnetic resonance imaging (MRI).

MATERIAL AND METHODS

Prospective study conducted from January 2000 to January 2020 in which 3132 patients aged between one day and 5 years underwent MRI under anaesthesia in an outpatient setting. The study population was divided into 4 subgroups: A) aged between one and 30 days; B) aged between one month and one year; C) aged between one and 3 years, and D) aged between 3 and 5 years. Study variables were: sex, age, type of examination, mean imaging time, mean time to awakening, heart rate before and after MRI, SatO₂, and incidence of complications such as respiratory depression (SatO₂ below 90%), agitation during the MRI or on awakening (intense crying lasting more than 2min), prolonged sedation measured on the Steward scale, and nausea and/or vomiting during the MRI, on awakening, or at home.

RESULTS

No notable hemodynamic alterations were observed. The incidence of desaturation was .41%, awakening during the test was .16%, prolonged sedation was 1.08%, and agitated awakening was 1.46%. Nausea and vomiting at the end of the test had an incidence of .73%. The P value in all cases was <.05%.

CONCLUSIONS

Chloral hydrate at a dose of 70mg/kg continues to be suitable in sedation lasting no more than one hour for non-invasive procedures in children, and is associated with adequate haemodynamic stability with practically no side effects.

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.

Efficacy and safety of intranasal dexmedetomidine versus oral chloral hydrate as sedatives for pediatric patients: a systematic review and meta-analysis

This study was designed to review published literature to determine the efficacy and safety of intranasal dexmedetomidine versus oral chloral hydrate (CH) for sedation in pediatric patients based on qualified studies. We searched the PubMed, Cochrane, and Embase databases for qualified studies published before March 2021. For each study, we analyzed the relative risk or weighted mean difference combined with a 95% CI. Fourteen studies including 3749 pediatric patients were included in this meta-analysis. Compared with oral CH, intranasal dexmedetomidine significantly increased the success rate of sedation and decreased the duration and latency of sedation, time of recovery from sedation, and total sedation time. Compared with oral CH, intranasal dexmedetomidine significantly decreased the incidence of adverse events, including vomiting, but increased the incidence of bradycardia. In conclusion, intranasal dexmedetomidine provides better sedation than oral CH for pediatric patients with good safety; however, the incidence of bradycardia is increased.

Anxiolysis for laceration repair in children: a survey of pediatric emergency providers in Canada

OBJECTIVES

Intranasal dexmedetomidine is a potentially effective anxiolytic but its role in pediatric laceration repair is only emerging. Future trials and clinical adoption of intranasal dexmedetomidine depend on understanding pediatric emergency providers' practice patterns surrounding anxiolysis and perceived barriers to intranasal dexmedetomidine for anxiolysis during suture repair in children. Our objectives were to characterize these parameters to inform future research and facilitate clinical adoption.

METHODS

We conducted an online survey of pediatric emergency physician members of Pediatric Emergency Research Canada from September to December 2020. Questions pertained to perceptions of anxiolysis for suture repair, with a focus on intranasal dexmedetomidine. The primary outcome was anxiolysis for suture repair. Data were reported using descriptive statistics.

RESULTS

The response rate was 155/225 (68.9%). During suture repair, 127/148 (86%) believed that > 25% of young children experience distress requiring physical restraint. 116/148 (78%) would provide anxiolysis, mainly intranasal benzodiazepines (100/148, 68%). Only 6/148 (4%) would provide intranasal dexmedetomidine but 95/148 (64%) would consider it if there was evidence of benefit. The most common perceived barriers to intranasal dexmedetomidine included inadequate personal experience (114/145, 79%) and lack of access (60/145, 41%).

CONCLUSIONS

Most Canadian pediatric emergency providers believe that laceration repair in a young child is distressing. Despite questionable efficacy, most would provide intranasal benzodiazepines, but would consider intranasal dexmedetomidine if there was evidence of benefit.

The Sedative Effects of Inhaled Nebulized Dexmedetomidine on Children: A Systematic Review and Meta-Analysis

BACKGROUND

Children that need surgery and medical examinations are often uncooperative, and preoperative sedation is necessary. We aimed to assess the safety and efficacy of inhaled nebulized dexmedetomidine in children for sedation that underwent medical examinations or surgery.

METHODS

We systematically searched PubMed, Web of science, Embase, and Cochrane library, for randomized controlled trials of Intranasal dexmedetomidine using a spray or a mucosal atomization device in children undergoing examination or elective surgery. We included all studies that analyzed the sedation efficiency of intranasal dexmedetomidine in children.

RESULTS

Ten studies with 1,233pediatric patients were included. Compared to other sedation treatments, inhaled nebulized dexmedetomidine showed similar sedation satisfaction [risk ratio RR: 1.02; 95% confidence interval (CI): 0.87-1.18; P = 0.83; I² = 72%]. there was also no statistical difference in the success rate of separation from parents (RR: 0.96; 95% CI: 0.82-1.12; P = 0.58; I² = 67%), and mask acceptability (RR: 1; 95% CI: 0.83-1.20; P = 0.99; I² = 35%). But it is worth mentioning that nebulized dexmedetomidine combined with ketamine provided better sedation satisfaction (RR: 0.69; 95% CI: 0.49-0.96; I² = 49%) and more satisfactory separation from parents (RR: 0.85; 95% CI: 0.74-0.97; I² = 0%). Moreover, nebulized dexmedetomidine reduced the occurrences of nausea and vomiting (RR: 0.28; 95% CI: 0.15-0.51; P < 0.01; I² = 10%) and emergence agitation (RR: 0.30; 95% CI: 0.18-0.49; P < 0.01; I² = 0%). There are no hypotension or arrhythmia reported that required intervention in all articles.

CONCLUSION

Compared to other premedication treatments, inhaled nebulized dexmedetomidine provided equivalent sedation satisfaction for the examination or preoperative sedation of children, but it reduced the occurrences of emergence agitation and postoperative nausea and vomiting.

Efficacy and Safety of Intranasal Dexmedetomidine vs. Oral Chloral Hydrate for Sedation in Children Undergoing Computed Tomography/Magnetic Resonance Imaging: A Meta-Analysis

OBJECTIVE

This meta-analysis aims to evaluate the sedative efficacy and safety of intranasal administration of dexmedetomidine (DEX) compared with oral chloral hydrate for Computed tomography (CT) or Magnetic Resonance Imaging (MRI) examination in Children.

METHODS

Cochrane Library, PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), and China WanFang Databases were searched to collect randomized controlled trials (RCTs) investigating intranasal DEX (test group) vs. oral chloral hydrate (control group) in pediatric CT/MRI examinations up to December 30, 2021. The data were analyzed using Stata 15.0 software.

RESULTS

Seven RCTs with 1,846 children were identified. The meta-analysis results showed that the success rate of sedation (RR = 1.14, 95% CI: 1.03-1.26, P = 0.011), sedation onset time [weighted mean difference (WMD) = -0.87, 95% CI: -1.42 to -0.31, P = 0.002], sedation duration (WMD = -9.05, 95% CI:-14.69 to -3.42, P = 0.002), time to awakening (WMD = -9.75, 95% CI:-17.57 to -1.94, P = 0.014), and incidence of nausea and vomiting [relative risk (RR) = 0.09, 95% CI:0.04-0.23, P < 0.001) of the test group were significantly better than those of the control group. However, no significant differences were identified in incidence of hypotension (RR = 1.18, 95% CI: 0.51-2.74) and bradycardia (RR = 1.17, 95% CI: 0.13-22.11) between the two groups.

CONCLUSION

Intranasal administration of DEX is superior to oral chloral hydrate for sedation during pediatric CT/MRI examinations and has a better safety profile.

Practical Considerations for Dexmedetomidine Sedation in Adult Cataract Surgery Under Local/Regional Anesthesia: A Narrative Review

Cataract surgery is predominantly performed under local/regional anesthesia, with or without sedation. The practice pattern of sedation is unknown and seems to vary significantly among institutions and countries, routinely administered in some parts of the world to the other extreme of none at all. The selection of sedative agents and techniques varies widely. Currently, there is no ideal sedative agent. Dexmedetomidine has gained recent attention for sedation in ophthalmic local/regional anesthesia due to its alleged advantages of effective sedation with minimal respiratory depression, decreased intraocular pressure, and reduced pain during the local anesthetic injection; however, they are subject to differing interpretations. Published literature also suggests that although dexmedetomidine sedation for cataract surgery under local/regional anesthesia is potentially useful, its role may be limited due to logistical difficulties in administering the recommended dose.

Use of a single dose of 70mg/kg chloral hydrate as a hypnotic in nuclear magnetic resonance. A prospective study of 3,132 cases

OBJECTIVE

To assess the mean time to hypnosis, hemodynamic stability, and incidence of complications associated with the administration of 70mg/kg oral chloral hydrate in children scheduled for magnetic resonance imaging (MRI).

MATERIAL AND METHODS

Prospective study conducted from January 2000 to January 2020 in which 3,132 patients aged between one day and 5 years underwent MRI under anaesthesia in an outpatient setting. The study population was divided into 4 subgroups: A) aged between one and 30 days; B) aged between one month and one year; C) aged between one and 3 years, and D) aged between 3 and 5 years. Study variables were: sex, age, type of examination, mean imaging time, mean time to awakening, heart rate before and after MRI, SatO2, and incidence of complications such as respiratory depression (SatO2 below 90%), agitation during the MRI or on awakening (intense crying lasting more than 2min), prolonged sedation measured on the Steward scale, and nausea and/or vomiting during the MRI, on awakening, or at home.

RESULTS

No notable hemodynamic alterations were observed. The incidence of desaturation was 0.41%, awakening during the test was 0.16%, prolonged sedation was 1.08%, and agitated awakening was 1.46%. Nausea and vomiting at the end of the test had an incidence of 0.73%. The P value in all cases was<.05%.

CONCLUSIONS

Chloral hydrate at a dose of 70mg/kg continues to be suitable in sedation lasting no more than one hour for non-invasive procedures in children, and is associated with adequate haemodynamic stability with practically no side effects.

Intranasal Dexmedetomidine Compared to a Combination of Intranasal Dexmedetomidine with Ketamine for Sedation of Children Requiring Dental Treatment: A Randomized Clinical Trial

Outpatient pediatric sedation is challenging. This study aimed to test intranasal dexmedetomidine efficacy as a single drug or combined with ketamine (DK) to sedate children undergoing dental treatment. Children < 7 years were randomized into dexmedetomidine 2 mcg/kg and ketamine 1 mg/kg (DK) or dexmedetomidine 2.5 mcg/kg (D) groups. Videos from the dental sedation allowed the systematic assessment of children's behavior (primary outcome) according to the Ohio State University Behavioral Rating Scale (OSUBRS). Secondary outcomes were parental and dentist satisfaction, adverse events, and recovery time. The data were analyzed descriptively and through regression models. Participants were 88 children (44 per group; 50 boys). The duration of quiet behavior (OSUBRS) was higher than 50% (DK mean 58.4 [standard deviation 38.1]; D 55.2 [39.1]; p = 0.225). Parents (DK 78.0 [32.2]; D 72.7 [35.1]; p = 0.203) and dentists (KD 62.7 [41.0]; D 62.8 [40.1]; p = 0.339) were overall satisfied. Adverse events occurred in 16 cases (DK n = 10, 62.5%; D n= 6, 37.5%; p = 0.104) and were minor. The median recovery time in the DK group was 1.3 times greater than in group D (p < 0.05). Intranasal sedation with dexmedetomidine alone is equally efficacious and satisfactory for pediatric sedation with fewer adverse events and faster recovery than the DK combination.

Intranasal dexmedetomidine versus oral midazolam premedication to prevent emergence delirium in children undergoing strabismus surgery: A randomised controlled trial

BACKGROUND

Dexmedetomidine is being used increasingly as a premedicant in the paediatric population. However, the effectiveness of pre-operative intranasal dexmedetomidine premedication, compared with oral midazolam, for emergence delirium is not well characterised.

OBJECTIVE

To identify the effectiveness of pre-operative intranasal dexmedetomidine for emergence delirium in the paediatric patient population following general anaesthesia.

DESIGN

A prospective, randomised, double-blind, parallel-group, placebo-controlled trial.

SETTING

Single university teaching hospital, from September 2013 to August 2014.

PATIENTS

One hundred and fifty-six patients undergoing anaesthesia for strabismus surgery were included in the study.

INTERVENTION

Patients were randomised in a 1 : 1 : 1 ratio to receive premedication with intranasal dexmedetomidine 2 μg kg (the dexmedetomidine group), oral midazolam 0.5 mg kg (the midazolam group), or 0.9% saline (the placebo group).

MAIN OUTCOME MEASURES

The primary outcome was the incidence of emergence delirium assessed by the Paediatric Anaesthesia Emergence Delirium scale. Secondary outcomes included the quality of the inhalational induction, emergence time, postoperative pain intensity, length of stay in the postanaesthesia care unit, the incidence of postoperative nausea or vomiting (PONV) and parents' satisfaction.

RESULTS

The incidence of emergence delirium was lower in patients given dexmedetomidine compared with that in patients given midazolam (11.5 versus 44%, relative risk = 0.262, 95% confidence interval 0.116 to 0.592) or 0.9% saline (11.5 versus 49%, relative risk = 0.235, 95% confidence interval 0.105 to 0.525). Likewise, the incidence of PONV was lower in the dexmedetomidine group (3.8%) than that in the midazolam (22%; P = 0.006) or placebo (29.4%; P < 0.001) groups. However, there was no difference among the groups concerning postoperative pain scores and length of postanaesthesia care unit stay.

CONCLUSION

In paediatric patients undergoing strabismus surgery intranasal dexmedetomidine 2 μg kg premedication decreases the incidence of emergence delirium and PONV, and improves parents' satisfaction compared with oral midazolam.

TRIAL REGISTRATION

ClinicalTrials.gov (identifier: NCT01895023).

Evaluation of Intranasal Dexmedetomidine as a Procedural Sedative for Ophthalmic Examination of Children With Glaucoma

PRECIS

This study evaluated 2 doses of intranasal dexmedetomidine (IND) (3.0 and 3.5 µg/kg) as a procedural sedative for postoperative examination of children with glaucoma. A dose of 3.5 µg/kg was more efficacious and obviated the need for repeated general anesthesia.

PURPOSE

This study was carried out to determine the safety and effective dose of IND as a procedural sedative for postoperative follow-up examinations after glaucoma surgery in children in place of repeated examination under anesthesia.

MATERIALS AND METHODS

In this prospective randomized double-blinded interventional study, consecutive children aged 6 months to 6 years were randomized to receive 3.0 and 3.5 µg/kg IND using a mucosal atomizer device in the preoperative area of the operating room, under continuous monitoring of vital signs. Intranasal midazolam 0.25 mg/kg was used as a rescue agent in case of inadequate sedation, and general anesthesia was administered in case of persistent failure. All infants underwent a complete anterior and posterior segment evaluation including intraocular pressure and corneal diameter measurements.

RESULTS

A total of 30 and 31 children aged 23.9±15.0 and 19.2±10.1 months, respectively, received 3.0 and 3.5 µg/kg IND. Adequate sedation was possible in 18 of 30 (60%) children receiving 3.0 µg/kg and 24 of 31 (77.4%) receiving 3.5 µg/kg IND alone (P=0.17). In combination with midazolam, successful sedations were 86.6% versus 100%, respectively (P=0.052). One patient in the 3.5 µg/kg group had ventricular arrhythmia, reversed with dextrose-saline infusion and injection glycopyrrolate.

CONCLUSIONS

IND appears to be a safe and effective procedural sedative for postoperative follow-up examinations of pediatric glaucoma patients at doses of 3 and 3.5 µg/kg. The dose of 3.5 µg/kg was successful in more children.

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.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Intranasal dexmedetomidine 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.

Intranasal dexmedetomidine versus oral chloral hydrate for diagnostic procedures sedation in infants and toddlers: A systematic review and meta-analysis

BACKGROUND

Intranasal dexmedetomidine is a relatively new way to sedate young children undergoing nonpainful diagnostic procedures. We performed a meta-analysis to compare the efficacy and safety of intranasal dexmedetomidine in young children with those of oral chloral hydrate, which has been a commonly used method for decades.

METHODS

We searched PubMed, Embase, and the Cochrane Library for all randomized controlled trials that compared intranasal dexmedetomidine with oral chloral hydrate in children undergoing diagnostic procedures. Data on success rate of sedation, onset time, recovery time, and adverse effects were extracted and respectively analyzed.

RESULTS

Five studies with a total of 720 patients met the inclusion criteria. Intranasal dexmedetomidine provided significant higher success rate of sedation (relative risk [RR], 1.12; 95% confidence interval [CI], 1.02 to 1.24; P = .02; I = 74%) than oral chloral hydrate. Furthermore, it experienced significantly shorter onset time (weight mean difference [WMD], -1.79; 95% CI, -3.23 to -0.34; P = .02; I = 69%). Nevertheless, there were no statistically differences in recovery time (WMD, -10.53; 95% CI, -24.17 to 3.11; P = .13; I = 92%) and the proportion of patients back to normal activities (RR, 1.11; 95% CI, 0.77-1.60; P = .57; I = 0%). Intranasal dexmedetomidine was associated with a significantly lower incidence of nausea and vomiting (RR, 0.05; 95% CI, 0.01-0.22; P < .0001; I = 0%) than oral chloral hydrate. Although adverse events such as bradycardia, hypotension and hypoxia were not synthetized due to lack of data, no clinical interventions except oxygen supplementation were required in any patients.

CONCLUSION

Our meta-analysis revealed that intranasal dexmedetomidine is possibly a more effective and acceptable sedation method for infants and toddlers undergoing diagnostic procedures than oral chloral hydrate. Additionally, it shows similar safety profile and could be a potential alternative to oral chloral hydrate.

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.

Efficacy of chloral hydrate oral solution for sedation in pediatrics: a systematic review and meta-analysis

Objective

Chloral hydrate (CH), as a sedation agent, is widely used in children for diagnostic or therapeutic procedures. However, it has not come into the market and is currently only used as hospital preparation in China. This review aims to systematically evaluate the efficacy of CH in children of all age groups for sedation before medical procedures.

Materials and methods

Seven electronic databases and three clinical trial registry platforms were searched and the deadline was September 2018. Randomized controlled trials (RCTs) evaluating the efficacy of CH for sedation in children were included by two reviewers. The extracted information included success rate of sedation, sedation latency and sedation duration. The Cochrane risk of bias tool was applied to assess the risk of bias. The outcomes were analyzed by Review Manager 5.3 software and expressed as relative risks (RR) or Mean Difference (MD) with 95% confidence interval (CI). Heterogeneity was assessed with I-squared (I²) statistics.

Results

A total of 24 RCTs involving 3564 children of CH for sedation were included in the meta-analysis. Compared to placebo group, CH group had a significant increase in success rate of sedation when used for painless and painful procedure (RR=4.15, 95% CI [1.21, 14.24], P=0.02; RR=1.28, 95% CI [1.17, 1.40], P<0.01), which included 22 and 455 children for this analysis, respectively. Compared to midazolam group, CH group had a significant increase in success rate of sedation (RR=1.63, 95% CI [1.48, 1.79], I²=0%, P<0.00001), sedation latency (MD=13.29, 95% CI [11.42, 15.16], I²=0%, P<0.00001) and sedation duration (MD=17.52, 95% CI [10.3, 24.71], I²=0%, P<0.05), which included 1052, 710 and 727 children for this analysis, respectively. Compared to diazepam, there was no significant difference in success rate of sedation (RR=0.93, 95% CI [0.80, 1.08], I²=52%, P=0.32), which included 230 children for this analysis. Compared to dexmedetomidine, there was no significant difference in the success rate of sedation (RR=0.92, 95% CI [0.80, 1.06], I²=48%, P=0.27) and sedation latency (RR=-1.09, 95% CI [-2.45, 0.26], I²=26%, P=0.11), which included 512 and 371 children for this analysis, respectively. Compared to barbiturates, there was no significant difference in the success rate of sedation (RR=1.03, 95% CI [0.94, 1.13], I²=50%, P=0.58) and sedation duration (MD=-0.72, 95% CI [-1.78, 0.34], I²=38%, P=0.18), which included 749 and 210 children for this analysis, respectively.

Conclusions

From the extrapolation of the existing literature, CH oral solution is an appropriate effective alternative for sedation in pediatrics.

Using anxiolytics in a pediatric otolaryngology clinic to avoid the operating room

INTRODUCTION

There is increasing concern regarding the risks associated with the use of general anesthesia in pediatric patients. Many otolaryngologic procedures performed under general anesthesia can also be performed in clinic. We hypothesize that anxiolytics can aid in performing common procedures in clinic thus avoiding the need to undergo general anesthesia in the OR.

METHODS

We performed a retrospective review of patients undergoing inoffice procedures with anxiolytics in our pediatric otolaryngology outpatient clinic between February 2013 and January 2017. Charts were reviewed for age, past medical history, procedure type/duration, and outcome. These results were then compared to a cohort undergoing similar procedures in the OR.

RESULTS

A total of 34 patients underwent an in-office procedure with an anxiolytic. The success rate was 97% (33/34). The average age was 6.2 years. Six children (17%) had a known history of chromosomal abnormalities and 2 children (6%) had autism. The four most common procedures performed were cerumen impaction removal (8), flexible laryngoscopy (6), ear canal foreign body removal (5), and septal cautery (4). Performing similar procedures in the OR resulted in an average additional cost of $822.

CONCLUSIONS

Performing procedures with anxiolytics in a pediatric otolaryngology clinic is safe, expeditious, and cost-effective. Anxiolytics can provide an effective alternative to general anesthesia.

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.

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.

Chloral Hydrate Administered by a Dedicated Sedation Service Can Be Used Safely and Effectively for Pediatric Ophthalmic Examination

PURPOSE

To determine safety and efficacy of oral chloral hydrate sedation (CHS) for outpatient pediatric ophthalmic procedures.

DESIGN

Prospective, interventional case series.

METHODS

Setting: King Khaled Eye Specialist Hospital.

SUBJECTS

Children aged 1 month to 5 years undergoing CHS for ocular imaging/evaluation.

PROCEDURES

Details on chloral hydrate dose administered, sedation achieved, vital signs, and adverse events were recorded.

OUTCOME MEASURES

Primary outcome was percentage of patients with a sedation level ≥ 4 at 45 minutes post chloral hydrate administration. Secondary outcomes were time from sedation to discharge and adverse events, including changes in vital signs following chloral hydrate administration.

RESULTS

A total of 324 children were recruited with a mean age of 2.2 (SD: 1.3) years and mean weight of 10.9 (SD: 3.3) kg. Adequate sedation was obtained with a mean chloral hydrate first dose of 77.4 (SD: 14.7) mg/kg in 306 (94.4%) patients, with an additional 6 patients (1.9%) achieving adequate sedation with a second dose (overall adequate sedation: 96.3%). Mean reductions in heart rate, respiratory rate, and oxygen (O₂) saturation from pre-sedation to 25 minutes post-sedation were 11.7 (SD: 14.3) beats per minute, 1.2 (SD: 2.4) breaths per minute, and 0.81% (SD: 1.2%), respectively (P < .001 for all). In multivariable regression, odds of remaining sedated 45 minutes after chloral hydrate administration were 2.53 times higher for American Society of Anesthesiologists (ASA) class II or III patients than for ASA class I (95% confidence interval [CI]: 1.11-5.78, P = .03), 1.03 times higher per mg increase in initial dose of chloral hydrate (95% CI: 1.01-1.06, P = .006), and 2.70 times higher per unit increase in number of planned procedures (95% CI: 1.63-4.47, P < .001). Three patients developed minor adverse events: 2 cases of O₂ desaturation and 1 paradoxical reaction, none requiring significant intervention. Patients were discharged a median of 90 minutes after chloral hydrate administration.

CONCLUSION

Chloral hydrate administered by a dedicated sedation service, as in this prospective assessment, can be used safely and effectively for outpatient pediatric ophthalmic procedures.

Sedation and Analgesia Using Medications Delivered via the Extravascular Route in Children Undergoing Laceration Repair

OBJECTIVES

To describe the method of delivery, dosage regimens, and outcomes of sedatives and analgesics administered via the extravascular route for laceration repair in children.

METHODS

Medline, Embase, and International Pharmaceutical Abstracts were searched using the keywords "child," "midazolam," "ketamine," dexmedetomidine," "fentanyl," "nitrous oxide" (N₂O), and "laceration repair." Articles evaluating the use of extravascular sedation in children for laceration repair published in the English language between 1946 and June 2017 were included. Two authors independently screened each article for inclusion. Reports were excluded if they did not contain sufficient details on dosage regimen and outcomes.

RESULTS

A total of 16 reports representing 953 children receiving sedatives and analgesics via the extravascular route were included for analyses. A statistical analysis was not performed because of heterogeneity in dosing and types of analyses conducted. Midazolam and N₂O were the most common agents, with oral (PO) midazolam being the most common agent. Other agents that have supporting data were intranasal (IN) dexmedetomidine, IN ketamine, IN midazolam, PO diazepam, PO ketamine, transmucosal (TM) midazolam, and TM fentanyl.

CONCLUSIONS

Most of the agents administered through the extravascular route were efficacious. Selection of the agents should be based on perceived need for analgesia versus sedation, patient accessibility, and adverse drug events. Future research is needed to determine the optimal agent and route for laceration repair.

Dexmedetomidine-based monitored conscious sedation combined local anesthesia for levator resection in a 10-year-old child with Marcus Gunn jaw-winking synkinesis: A case report

RATIONALE

Levator resection has become a routine procedure for patients with severe Marcus Gunn jaw-winking synkinesis (MGJWS). To optimize the surgical outcome, adult patients need to be kept awake, or easily aroused and responsive to verbal commands during the operation. However, levator resection is commonly performed under general anesthesia in pediatric patients. In the present case, we described a successful anesthetic protocol of conscious sedation with local anesthesia for levator resection in a child.

PATIENT CONCERNS

A 10-year-old boy with MGJWS was admitted to our hospital and scheduled for levator resection. The patient was born through a normal delivery and had no previous history of allergy, no comorbidity, and no history of receiving anesthesia or operation. The laboratory tests of the patient were unremarkable.

DIAGNOSES

The diagnosis of MGJWS was made by two experienced ophthalmologists.

INTERVENTIONS

A 10-year-old boy with MGJWS was admitted to our hospital and scheduled for levator resection. The levator resection was performed under monitored conscious sedation with dexmedetomidine and local anesthesia.

OUTCOMES

Patient with spontaneous breathing responded normally to verbal commands throughout the operation, and no adverse events occurred. The patient and ophthalmologist reported high satisfaction with anesthesia management.

LESSONS

Dexmedetomidine-based monitored conscious sedation with local anesthesia is a feasible alternative to general anesthesia for levator resection in collaborative patients.

Monitoring and Morphologic Classification of Pediatric Cataract Using Slit-Lamp-Adapted Photography

Purpose

To investigate the feasibility of pediatric cataract monitoring and morphologic classification using slit lamp–adapted anterior segmental photography in a large cohort that included uncooperative children.

Methods

Patients registered in the Childhood Cataract Program of the Chinese Ministry of Health were prospectively selected. Eligible patients underwent slit-lamp adapted anterior segmental photography to record and monitor the morphology of their cataractous lenses. A set of assistance techniques for slit lamp–adapted photography was developed to instruct the parents of uncooperative children how to help maintain the child's head position and keep the eyes open after sleep aid administration.

Results

Briefly, slit lamp–adapted photography was completed for all 438 children, including 260 (59.4%) uncooperative children with our assistance techniques. All 746 images of 438 patients successfully confirmed the diagnoses and classifications. Considering the lesion location, pediatric cataract morphologies could be objectively classified into the seven following types: total; nuclear; polar, including two subtypes (anterior and posterior); lamellar; nuclear combined with cortical, including three subtypes (coral-like, dust-like, and blue-dot); cortical; and Y suture. The top three types of unilateral cataracts were polar (55, 42.3%), total (42, 32.3%), and nuclear (23, 17.7%); and the top three types of bilateral cataracts were nuclear (110, 35.8%), total (102, 33.2%), and lamellar (34, 11.1%).

Conclusions

Slit lamp–adapted anterior segmental photography is applicable for monitoring and classifying the morphologies of pediatric cataracts and is even safe and feasible for uncooperative children with assistance techniques and sleep aid administration.

Translational Relevance

This study proposes a novel strategy for the preoperative evaluation and evidence-based management of pediatric ophthalmology (Clinical Trials.gov, NCT02748031).