The use of melatonin as an alternative to sedation in uncooperative children undergoing an MRI examination

Efficacy of Melatonin as a Sleep Inducer in EEG Procedures in the Pediatric Population: A Cross-Sectional Study

Introduction Melatonin has been used as an alternative to sleep deprivation for EEG sleep induction in the pediatric population. Our study aims to describe the efficacy of the currently used doses of melatonin for sleep induction among the pediatric age group. Methods A retrospective cross-sectional study included all patients who underwent an EEG after receiving melatonin over the period of one year. A total of 126 patients have been included in the study. Patients aged one year to three years received oral melatonin in doses between 2 mg and 6 mg. Patients in the age of three years and above received 10 mg of melatonin. Patients' success rate in achieving sleep and the exact time required for the patients to fall asleep were obtained using the readings of their EEG. The percentage of patients who have achieved sleep and the time required for those patients to sleep were calculated and correlated with the patient's gender, the presence of any associated neurobehavioral disorders, and their use of antiepileptic drugs (AED). Results Successful sleep was achieved in 84.9% (n:107) of the patients, with a mean time of 24 minutes to fall asleep (SD = 14.36). Patients with neurobehavioral disorders were 20% less likely to fall asleep when compared to other patients without neurobehavioral disorders (p: 0.003). However, there was not a statistically significant difference among different genders and among patients who received AED. Conclusion Melatonin is an effective sleep inducer for patients undergoing EEG procedures. It should be considered in the majority of patients. However, in patients with neurobehavioral disorders, a lower success rate is expected.

Behavioral-play familiarization for non-sedated magnetic resonance imaging in young children with mild traumatic brain injury

BACKGROUND

Mild traumatic brain injury (mTBI) sustained in early childhood affects the brain at a peak developmental period and may disrupt sensitive stages of skill acquisition, thereby compromising child functioning. However, due to the challenges of collecting non-sedated neuroimaging data in young children, the consequences of mTBI on young children's brains have not been systematically studied. In typically developing preschool children (of age 3-5years), a brief behavioral-play familiarization provides an effective alternative to sedation for acquiring awake magnetic resonance imaging (MRI) in a time- and resource-efficient manner. To date, no study has applied such an approach for acquiring non-sedated MRI in preschool children with mTBI who may present with additional MRI acquisition challenges such as agitation or anxiety.

OBJECTIVE

The present study aimed to compare the effectiveness of a brief behavioral-play familiarization for acquiring non-sedated MRI for research purposes between young children with and without mTBI, and to identify factors associated with successful MRI acquisition.

MATERIALS AND METHODS

Preschool children with mTBI (n=13) and typically developing children (n=24) underwent a 15-minutes behavioral-play MRI familiarization followed by a 35-minutes non-sedated MRI protocol. Success rate was compared between groups, MRI quality was assessed quantitatively, and factors predicting success were documented.

RESULTS

Among the 37 participants, 15 typically developing children (63%) and 10 mTBI (77%) reached the MRI acquisition success criteria (i.e., completing the two first sequences). The success rate was not significantly different between groups (p=.48; 95% CI [-0.36 14.08]; Cramer's V=.15). The images acquired were of high-quality in 100% (for both groups) of the structural images, and 60% (for both groups) of the diffusion images. Factors associated with success included older child age (Β=0.73, p=.007, exp(B)=3.11, 95% CI [1.36 7.08]) and fewer parental concerns (Β=-1.56, p=.02, exp(Β)=0.21, 95% CI [0.05 0.82]) about the MRI procedure.

CONCLUSION

Using brief behavioral-play familiarization allows acquisition of high-quality non-sedated MRI in young children with mTBI with success rates comparable to those of non-injured peers.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Behavioral and cardiovascular effects of a single dose of gabapentin or melatonin in cats: a randomized, double-blind, placebo-controlled trial

OBJECTIVES

The aim of this study was to verify whether a single oral dose of gabapentin (100 mg) or melatonin (3 mg) given 60 mins before a cardiac evaluation would reduce anxiety without interfering with heart rate (HR), systemic blood pressure (SBP), electrocardiogram (ECG) and echocardiographic indexes.

METHODS

Seventy-five client-owned healthy cats underwent two sets of cardiac assessments 60 mins apart, randomly divided into gabapentin, melatonin and placebo groups. The interval between treatment and the second ECG and SBP measurement was 60 mins, and 70 mins for echocardiography. A compliance score (CS) classified the behavior, focusing on the ease of handling.

RESULTS

Most variables did not change between the examinations. The placebo group showed more significant changes (SBP, tricuspid annular plane systolic excursion, HR during echocardiography, aortic flow velocity, S' wave from lateral mitral annulus), but they were not considered to be hemodynamically relevant. Gabapentin and melatonin significantly increased the cats' compliance without interfering with cardiac assessment. Eight cats presented with mild sedation, seven after gabapentin and one after melatonin. No major side effects were observed.

CONCLUSIONS AND RELEVANCE

Gabapentin tranquilized the cats when it was given 60 mins prior to ECG and SBP measurement, and 70 mins prior to echocardiography, without interfering with systolic echocardiographic indexes. Melatonin also decreased the CS, but without sedation in most cases. The waiting period may have relaxed the cats in the placebo group, resulting in lower SBP measurements. However, this tranquility did not last as some echocardiographic changes signaled a sympathetic predominance.

The Effect of Pre-emptive Oral Melatonin versus Placebo on Post-operative Analgesia in Infants after Thoracotomy for Closed Cardiac Surgeries: A Randomized Controlled Study

BACKGROUND: Thoracotomy pain is one of the severest types of pain that should be managed properly, especially in children. Opioids are the most widely prescribed analgesics for post-operative pain, but they can have a number of undesirable side effects. Melatonin could be employed as an adjuvant analgesic therapy during procedural discomfort as it had no known major side effects. STUDY DESIGN: This was a double-blinded, controlled randomized study. METHODS: Fifty patients divided randomly into two equal groups. One hour before surgery, children in M group (n = 25) were given 0.5 mg/kg orally of melatonin 3 mg tablets) and patients in Group P (n = 25) received a placebo (5 ml of water by syringe 5 ml) orally. Post-operative pethidine consumption over the 1st 24 h (mg) was recorded, the intraoperative fentanyl consumption (HR and ABP) at baseline, 1 min after induction, at skin incision, and every 30 min till the end of the surgery were recorded. Neonatal Infant Pain Score (NIPS) at 4 h, 6 h, 8 h, 12 h, 18 h, and 24 h postoperatively was recorded. Other reported data include demographic data, extubation time, days of ICU stay, and complications. RESULTS: Total post-operative pethidine consumption (mg) over 24 h was significantly lower in M group than P group (3.48 ± 2.23 vs. 7.68 ± 4.52 p = 0.01). Intraoperative fentanyl consumption (ug) was significantly lower in M group than P group (10.28 ± 4.98 vs. 17.08 ± 7.39 p < 0.001). As regards NIPS, it was statistically lower in M group than P group in all times except at 8 h and 24 h with significant difference. CONCLUSION: Oral melatonin is an effective and safe pre-emptive drug as it reduces the total post-operative pethidine consumption over the first 24 h and decreased post-operative pain scores without any unpleasant effects in pediatrics undergoing closed heart surgery.

Melatonin for pre-medication in children: a systematic review

Background

Melatonin’s effectiveness as an anxiolytic medication has been confirmed in adults; however, its efficacy in a paediatric population is unclear. A number of small studies have assessed its use in children as a pre-operative anxiolytic, with conflicting results.

Methods

We undertook a systematic review of pre-operative melatonin use in children. Four databases (MEDLINE, Embase, the Cochrane Central Register of Controlled Trials and Web of Science), and ‘ClinicalTrials.gov’ were searched for ongoing and completed clinical trials of relevance. Citation tracking reference lists and relevant articles were also accessed. The review was unrestricted by comparator or outcomes. Eleven studies were judged eligible for inclusion. There were high levels of heterogeneity in melatonin administration (in terms of dose and timing). Variable outcomes were reported and included: anxiety; anaesthetic success; analgesia; sedation; post-operative recovery; and safety. Outcomes were not always assessed with the same measures.

Results

Evidence to support melatonin’s anxiolytic properties in this setting is conflicting. Melatonin was associated with reduced sedative effects, post-operative excitement and improved emergence behaviour, compared to comparator drugs. One study reported the benefit of melatonin use on sleep disturbance at two weeks post-surgery. No adverse safety events were identified to be significantly associated with melatonin, affirming its excellent safety profile.

Conclusion

Despite potential advantages, including improved emergence behaviour, based on current evidence we cannot confirm whether melatonin is non-inferior to current “usual care” pre-medications. Further consideration of melatonin as an anxiolytic pre-medication in paediatric surgery is needed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03149-w.

Melatonin for non-operating room sedation in paediatric population: a systematic review and meta-analysis

CONTEXT

The literature on melatonin as a sedative agent in children is limited.

OBJECTIVE

To conduct a systematic review of studies assessing the efficacy and safety of melatonin for non-operating room sedation in children.

METHODS

Medline, Embase, Cochrane Library and Cumulative Index to Nursing and Allied Health were searched until 9 April 2020 for studies using melatonin and reporting one of the prespecified outcomes of this review. Two authors independently assessed the eligibility, risk of bias and extracted the data. Studies with a similar study design, comparator and procedure were pooled using the fixed-effect model.

RESULTS

25 studies (clinical trials=3, observational studies=9, descriptive studies=13) were included. Melatonin was used for electroencephalogram (EEG) (n=12), brainstem evoked response audiometry (n=8) and magnetic resonance imaging (MRI) (n=5). No significant differences were noted on meta-analysis of EEG studies comparing melatonin with sleep deprivation (SD) (relative risk (RR) 1.06 (95% CI 0.99 to 1.12)), melatonin with chloral hydrate (RR 0.97 (95% CI 0.89 to 1.05)) and melatonin alone with melatonin and SD combined (RR 1.03 (95% CI 0.97 to 1.10)) for successful procedure completion. However, significantly higher sedation failure was noted in melatonin alone compared with melatonin and SD combined (RR 1.55 (95% CI 1.02 to 2.33)) for EEG. Additionally, meta-analysis showed lower sleep latency for melatonin compared with SD (mean difference -10.21 (95% CI -11.53 to -8.89) for EEG. No major adverse events were reported with melatonin.

CONCLUSION

Although several studies were identified, and no serious safety concerns were noted, the evidence was not of high quality to establish melatonin's efficacy for non-operating room sedation in children.

Characterisation of Children's Head Motion for Magnetic Resonance Imaging With and Without General Anaesthesia

Head motion is one of the major reasons for artefacts in Magnetic Resonance Imaging (MRI), which is especially challenging for children who are often intimidated by the dimensions of the MR scanner. In order to optimise the MRI acquisition for children in the clinical setting, insights into children's motion patterns are essential. In this work, we analyse motion data from 61 paediatric patients. We compare structural MRI data of children imaged with and without general anaesthesia (GA), all scanned using the same hybrid PET/MR scanner. We analyse several metrics of motion based on the displacement relative to a reference, decompose the transformation matrix into translation and rotation, as well as investigate whether different regions in the brain are affected differently by the children's motion. Head motion for children without GA was significantly higher, with a median of the mean displacements of 2.19 ± 0.93 mm (median ± standard deviation) during 41.7±7.5 min scans; however, even anaesthetised children showed residual head motion (mean displacement of 1.12±0.35 mm). For both patient groups translation along the z-axis (along the scanner bore) was significantly larger in absolute terms (GA / no GA: 0.87±0.29/0.92 ± 0.49 mm) compared to the other directions. Considering directionality, both patient groups were moving in negative z-direction and thus, out of the scanner. The awake children additionally showed significantly more nodding rotation (0.33±0.20°). In future studies as well as in the clinical setting, these predominant types of motion need to be taken into consideration to limit artefacts and reduce re-scans due to poor image quality.

Pharmacological and philosophical considerations for the around-the-clock use of scheduled melatonin to promote sedation and reduce aggression in individuals with serious mental illness: a case report

Melatonin, the endogenous hormone that helps maintain circadian rhythm, has been used exogenously for both primary and secondary sleep disorders. While the effects of melatonin given prior to planned sleep and to restore normal circadian sleep phases have been well studied, there is little information on the use of melatonin as a pharmacotherapeutic intervention for around-the-clock sedation to prevent agitation and aggressive patient behaviors. This is the first case report to our knowledge of melatonin used throughout the day, as a scheduled dose for prolonged treatment duration, to reduce aggression in a patient with severe mental illness.

Efficacy and tolerability of Melatonin vs Triclofos to achieve sleep for pediatric electroencephalography: A single blinded randomized controlled trial

PURPOSE

To compare Melatonin with Triclofos for efficacy (proportion of successful EEG, need of augmentation, sleep onset latency (SOL), yield of discharges, duration of sleep, presence and grade of artifacts) and tolerability (adverse effect profile).

METHODS

A randomized trial was performed (block randomization). All children were advised regarding sleep deprivation, EEG technician administered the drug. EEG was labelled successful if at least 30 min of record could be obtained (sleep with or without awake state). Pediatric neurologist reported the EEG findings-sleep onset latency, epileptiform abnormalities and graded the artifacts (excess beta activity and movement artifacts if present). The parents were interviewed telephonically next day by a pediatric resident for any adverse effects. The parents, pediatric neurologist and pediatric resident were blinded for the drug given.

RESULTS

228 children were randomized (114 each received Melatonin and Triclofos). Both the groups were comparable at baseline for age group and demographic data. The proportion of successful EEG was 89.4% in Melatonin and 91.2% in Triclofos. First dose was effective in 64% in Melatonin and 63.15% in Triclofos group. Augmentation dose was needed in 25.4% in Melatonin and 28% in Triclofos group. Mean total sleep duration was 80 min after Melatonin and 82.39 after Triclofos administration. Adverse effects were observed in 6.14% of Melatonin and 8.65% of Triclofos group. None of the results were statistically significant.

CONCLUSION

There was no significant difference between efficacy and tolerability of Melatonin and Triclofos. Melatonin can be safely used to achieve sleep for EEG in children.

Melatonin for anaesthetic indications in paediatric patients: a systematic review

The favourable safety profile and ubiquitous nature of melatonin has led to an increase in its use in various clinical settings in adults and children. We performed a systematic review of published studies on the use of melatonin for anaesthetic indications in paediatric patients. To identify relevant articles, PubMed, EMBASE, Cumulative Index to Nursing and Allied Health Literature, Web of Science and Scopus databases were searched. Study title and abstract screening, and full text review were performed by two reviewers. Twenty-seven eligible studies investigating melatonin use for anaesthetic indications were identified. Due to significant heterogeneity in study methodology, a quantitative synthesis of the published findings was not possible. The identified studies were therefore categorised by the indication for melatonin: analgesia, diagnostic sedation and as an anaesthetic adjunct. Melatonin use for anaesthetic-related indications is safe; may provide analgesia for inflammatory-associated pain in neonates and children before venepuncture; may decrease the need for, or replace, general anaesthesia for diagnostic procedures; and may serve as an anaesthesia adjunct before induction in paediatric patients.

Melatonin is useful alternative for sedation in children undergoing auditory brainstem responses testing

Auditory brainstem responses testing (ABRs) is frequently required to assess auditory function in children. It is done usually in outpatient fashion and requires deep sleep to avoid artefacts. Sedation method used for the test should allow a deep sleep while avoiding general anaesthesia that requires special monitoring, dedicated staff and operating room availability. For this purpose, several sedation methods have been used, with the risk of respiratory depression and sides effects. We aim to assess the efficacy and the usefulness of melatonin in sedation for children undergoing auditory brainstem responses testing. We calculated success rate of complete bilateral ABR, sleep delay and quality of sleep of 247 children referred for ABR testing. Two hundred six children (83.4%) successfully underwent both ears testing. The delay to sleep was variable with a mean of 32 min. The quality of sleep was described as continuous in 156 infants (75.7%) and discontinuous in 50 infants (24.27%) requiring either simple nursing or a second dose of melatonin 30 min later.Conclusion: Melatonin has the advantages of inducing natural sleep and reducing sleep delay without adverse effects or respiratory depression risk. It is efficient and useful sedation method for ABRs in an outpatient setting. What Is Known? • Auditory brainstem responses test is the most used objective test to assess auditory function in children and requires deep sleep to avoid artefacts. • Melatonin is an endogenous pineal hormone used for sedation in electrophysiological testing and magnetic resonance imaging. What Is New? • 83.4% of children in our study successfully performed a bilateral ABR under melatonin-induced sleep with continuous sleep in 75.7%. • The use of melatonin to induce sleep for ABR tests is useful in an outpatient setting and it is a good alternative to general anaesthesia in Morocco.

Melatonin Use in Hospitalized Children for Non-Anesthetic Indications: A Systematic Review

Melatonin, a potent free radical scavenger, plays an important role in homeostasis of cell and organ physiology. The increased demand and synthesis from the pineal gland during times of oxidative stress suggests a potential benefit of melatonin supplementation during hospitalization for acute illness. Yet, the paucity of clinical studies for non-anesthetic-associated indications in pediatric populations hampers the safe, effective, and consistent use of melatonin. The objective of this study was to systematically review published studies of melatonin use for non-sedative and non-analgesic indications in hospitalized pediatric patients. We conducted a search of PubMed, EMBASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Web of Science, and Scopus databases for articles on the use of melatonin for pediatric patients in a hospital setting. Thirteen eligible studies, all in neonates, were identified. Data elements extracted included study design, number of study subjects, indication for melatonin therapy, and melatonin regimen (formulation, dosage, and duration). Because study methodologies were very heterogeneous, a quantitative synthesis of the published findings was not possible. The identified studies were therefore categorized by the indication of melatonin (adjuvant-antioxidant or anti-inflammatory therapy) in the following specific disease states: (i) acute infections, (ii) respiratory distress syndrome, (iii) neurologic injury, and (iv) jaundice. The current data suggest that melatonin is safe for use in hospitalized neonates. Melatonin may be beneficial for reducing inflammatory markers in neonatal patients with disease states and clinical sequelae that are associated with increased inflammation and oxidative stress. Melatonin, in conjunction with phototherapy, is not superior to use of vitamin D with phototherapy for treatment of neonatal jaundice. However, studies in other pediatric populations are needed given widespread use across clinical inpatient settings.

Neuroimaging young children and associations with neurocognitive development in a South African birth cohort study

Magnetic resonance imaging (MRI) is an indispensable tool for investigating brain development in young children and the neurobiological mechanisms underlying developmental risk and resilience. Sub-Saharan Africa has the highest proportion of children at risk of developmental delay worldwide, yet in this region there is very limited neuroimaging research focusing on the neurobiology of such impairment. Furthermore, paediatric MRI imaging is challenging in any setting due to motion sensitivity. Although sedation and anesthesia are routinely used in clinical practice to minimise movement in young children, this may not be ethical in the context of research. Our study aimed to investigate the feasibility of paediatric multimodal MRI at age 2–3 years without sedation, and to explore the relationship between cortical structure and neurocognitive development at this understudied age in a sub-Saharan African setting. A total of 239 children from the Drakenstein Child Health Study, a large observational South African birth cohort, were recruited for neuroimaging at 2–3 years of age. Scans were conducted during natural sleep utilising locally developed techniques. T1-MEMPRAGE and T2-weighted structural imaging, resting state functional MRI, diffusion tensor imaging and magnetic resonance spectroscopy sequences were included. Child neurodevelopment was assessed using the Bayley-III Scales of Infant and Toddler Development. Following 23 pilot scans, 216 children underwent scanning and T1-weighted images were obtained from 167/216 (77%) of children (median age 34.8 months). Furthermore, we found cortical surface area and thickness within frontal regions were associated with cognitive development, and in temporal and frontal regions with language development (beta coefficient ≥0.20). Overall, we demonstrate the feasibility of carrying out a neuroimaging study of young children during natural sleep in sub-Saharan Africa. Our findings indicate that dynamic morphological changes in heteromodal association regions are associated with cognitive and language development at this young age. These proof-of-concept analyses suggest similar links between the brain and cognition as prior literature from high income countries, enhancing understanding of the interplay between cortical structure and function during brain maturation.

•

MRI data are challenging to acquire in the early years of life.

•

Paediatric MRI without sedation is feasible in sub-Saharan Africa, with 77% success.

•

The Drakenstein Child Health study has novel MRI data of South African children.

•

Morphological features of the cortex associate with neurocognitive development.

•

Structure-cognition relationships in heteromodal association regions at 2–3 years.

Efficacy of melatonin for auditory brainstem response testing in children: A systematic review

OBJECTIVE

To examine the literature on pre-treatment with melatonin for successful completion of Auditory Brainstem Response (ABR) testing in pediatric patients and evaluate melatonin dosing protocols.

DATA SOURCES

The Cochrane Library, PubMed, Ovid MEDLINE, and Web of Science from inception through May 20th, 2019. In addition, a retrospective case series of pediatric patients (<18yr) who underwent melatonin assisted ABR testing between 2015 and 2018 was performed at our institution.

REVIEW METHODS

Prospective and retrospective studies involving melatonin use in pediatric patients (<18yrs) for auditory brainstem response testing were evaluated. Studies meeting inclusion/exclusion criteria reported success rate of ABR testing using melatonin pre-treatment, dosage of melatonin used, duration of sleep, and whether adverse events occurred.

RESULTS

43 studies were identified, 8 studies were selected, and finally 5 studies were included in the review. A total of 480 pediatric patients underwent ABR testing with pre-treatment of melatonin with success rates ranging from 65% to 86.7%. Age across studies ranged from 1 month to 14 years, 6 months. Dosage of melatonin varied from 0.25 mg for patients <3 months of age to 20 mg for patients >6 years of age, with one study using a weight-based approach. No significant adverse events were reported by any of the included studies.

CONCLUSION

Pre-medication with melatonin may be a useful option for obtaining successful results of non-sedated ABR testing in pediatric patients and may provide a useful alternative to sedation. Dosing patterns are highly variable. No adverse events were reported with any dosing strategy.

Melatonin in neuropaediatric MRI: a retrospective study of efficacy in a general hospital setting

BACKGROUND

Melatonin may offer a safe and cheap alternative to general anaesthesia and sedatives in neuropaediatric MRI. The purpose of our study was to evaluate its efficacy during a daily scanning programme and to assess its financial benefit.

METHODS

Neuro-MRI scans, performed in a general hospital setting after administration of melatonin in 64 children aged 10 months-5 years, were retrospectively reassessed by an experienced paediatric neuroradiologist, rating them as diagnostically contributing or as failed. The financial benefit was calculated.

RESULTS

49/64 scans (77%) were diagnostically contributing, in 11 (22%) no movement artefact was seen in any sequence; 15/64 scans failed (23%), in 3/15 because of serious movement artefacts, in 12/15 the scan was not started. Repeat scans under general anaesthesia were performed in 17 cases (27%): in the 15 failed cases and in 2 cases initially assessed as failed, but were considered diagnostically contributing in the present study. The financial benefit at the time the scans were made was approximately 13,360 Euro.

CONCLUSIONS

In this retrospective study, the use of melatonin in neuropaediatric MRI, made during a daily scanning programme with a remote waiting room, was associated with a high success rate in infants and young children. A minority of scans had no movement artefacts, indicating most children were not asleep. The sleep-inducing effect of melatonin could therefore not be proven, but the high success rate may be attributed to the sedative and/or anxiolytic effect of melatonin. Only a minority of scans had to be repeated under general anesthesia, leading to a reduction of scan related costs.

A solution based on melatonin, tryptophan, and vitamin B6 (Melamil Tripto©) for sedation in newborns during brain MRI

INTRODUCTION

Melatonin has been studied and used for several years as a sleep-wake cycle modulator in patients with sleep disorders. Experimental evidence has demonstrated the multiple neuroprotective benefits of this indoleamine secreted by the pineal gland. Melatonin is also used in neurological investigations, for its ability to induce sleep in children. In fact, it favors falling asleep during electroencephalogram, Magnetic Resonance Imaging (MRI), and during brainstem auditory evoked potentials. Previous studies are focused on infants and children. No investigation have been performed in neonates, before or during instrumental assessments.

MATERIAL AND METHODS

One hundred ten newborns (term and preterm) undergoing brain MRI were enrolled in the study. Thirty minutes before the planned time for the examination, we administered a single dose solution of melatonin- tryptophan-vitamin B6. Twenty minutes after the initial administration of 2 mg, a second dose of 1 mg was administered, if the baby was still awake. If after further 15 min the baby was still not sleeping, an additional dose of 1 mg was administered.

RESULTS

In 106 patients we obtained adequate sedation without adverse events, allowing us to perform an adequate quality MRI, with a median time of 25 min to reach sleeping. Only in three patients MRI could not be performed. In patients having a large weight, higher doses of melatonin were necessary to reach sleeping. Considering the pro kg dose of melatonin, the average dose that induced sleepiness in neonates was 0,64 ± 0.16 mg/Kg.

CONCLUSION

A solution based on Melatonin- tryptophan-vitamin B6 can be a helpful sedative to administer to neonates undergoing brain MRI, avoiding the use of anesthetics and achieving adequate assessments.

Transmucosal delivery of melatonin-encapsulated niosomes in a mucoadhesive gel

AIM

A transmucosal niosome gel was developed to improve the pharmacokinetics of exogenous melatonin.

MATERIALS & METHODS

The melatonin niosomes (MN) gel was characterized and melatonin levels were determined in healthy volunteers.

RESULTS

Micron-sized MN in a gel, mean ex vivo residence time of more than 3 h with maximum adhesiveness at 25 and 37°C showed similar in vitro release but different in vitro permeation to melatonin gel. Oral transmucosal MN gels, at 2.5, 5 and 10 mg, topically applied in 14 healthy volunteers in a randomized double-blinded crossover design with 7-day washout, gave dose-proportional pharmacokinetics, with improved absorption and prolonged systemic circulation.

CONCLUSION

The transmucosal MN gel provides a topical option for melatonin administration with substantial prolonged systemic delivery.

The potential utility of melatonin in the treatment of childhood cancer

Childhood cancer management has improved considerably, with the overall objective of preventing early-life cancers completely. However, cancer remains a major cause of death in children, with the survivors developing anticancer treatment-specific health problems. Therefore, the anticancer treatment needs further improvement. Melatonin is a effective antioxidant and circadian pacemaker. Through multiple mechanisms, melatonin has significant positive effects on multitude adult cancers by increasing survival and treatment response rates, and slowing disease progression. In addition, melatonin appears to be safe for children. As an appealing therapeutic agent, we herein address several key concerns regarding melatonin's potential for treating children with cancer.

Correction to: Melatonin as an alternative sedation method during magnetic resonance imaging in preschool children with musculoskeletal problems

AbstractMagnetic resonance imaging (MRI) in preschool children is often challenging due to excessive motion artifacts. Sedation or general anesthesia (GA) are commonly used to prevent children from moving in the MRI scanner, with increased risk for cardiopulmonary complications and requirement for skilled personnel. Herein we investigated whether oral melatonin, a natural hormone implicated in circadian rhythm regulation, could be used as an alternative sedation method prior to the MRI in preschool children with musculoskeletal problems. Fifteen children with suspected juvenile idiopathic arthritis underwent a total of 16 MRI examinations following administration of 10 mg of oral melatonin; satisfactory images were obtained in all but one case, with no adverse events.Conclusion: The use of melatonin before the musculoskeletal MRI in preschool children is an effective, safe and inexpensive alternative to standard sedation and general anesthesia in preventing motion artifacts. What is known: • Magnetic resonance imaging (MRI) is a well-recognized diagnostic method to visualize synovial inflammation and changes of cartilage and bone in juvenile idiopathic arthritis.• MRI examination requires sedation or general anesthesia to ensure immobility in children who are uncooperative. What is new: • Additional to previous published studies we were able to show that melatonin for sedation for an MRI of joints, even without sleep deprivation, in the studied population may provide an alternative in children without behavioral problems, in order to avoid sedation/GA.

Melatonin as an alternative sedation method during magnetic resonance imaging in preschool children with musculoskeletal problems

Magnetic resonance imaging (MRI) in preschool children is often challenging due to excessive motion artifacts. Sedation or general anesthesia (GA) is commonly used to prevent children from moving in the MRI scanner, with increased risk for cardiopulmonary complications and requirement for skilled personnel. Herein, we investigated whether oral melatonin, a natural hormone implicated in circadian rhythm regulation, could be used as an alternative sedation method prior to the MRI in preschool children with musculoskeletal problems. Fifteen children with suspected juvenile idiopathic arthritis underwent a total of 16 MRI examinations following administration of 10 mg of oral melatonin; satisfactory images were obtained in all but one case, with no adverse events.

CONCLUSION

The use of melatonin before the musculoskeletal MRI in preschool children is an effective, safe, and inexpensive alternative to standard sedation and general anesthesia in preventing motion artifacts. What is Known: • Magnetic resonance imaging (MRI) is a well-recognized diagnostic method to visualize synovial inflammation and changes of cartilage and bone in juvenile idiopathic arthritis. • MRI examination requires sedation or general anesthesia to ensure immobility in children who are uncooperative. What is New: • Melatonin without sleep deprivation is efficacious and safe alternative to conventional sedation and general anesthesia before the musculoskeletal contrast-enhanced MRI in preschool children with JIA with timely insertion of intravenous cannula.

Need for a standardized technique of nap EEG recordings: results of a national online survey in Italy

The aim of this study is to report current clinical practice for sleep induction in Italian epilepsy centers. We administered an online-structured survey between March and November 2017 and collected data from pediatric and adult neurophysiologists belonging to 73 epilepsy centers. The preferred time for EEG recording is variable, depending on daily schedule of each laboratory. To facilitate spontaneous sleep during nap EEGs, almost all centers require sleep deprivation before the examination, with partial loss preferred to total deprivation in most centers (58/73 vs 12/73, p < 0.001). Other non-pharmacological procedures include breast/bottle feeding or listening to music (encouraged in most centers). Pharmacological sleep induction is performed in 40% of laboratories, more commonly in children than in adults (27/60 vs 7/42, p = 0.003). Melatonin is the most frequently prescribed drug to facilitate spontaneous sleep (one third of participating centers). Our study highlights the great heterogeneity among Italian epilepsy centers in current clinical practice for sleep EEG recordings. Expert consensus for sleep induction procedure is warranted.

The environmental neurotoxin β-N-methylamino-L-alanine inhibits melatonin synthesis in primary pinealocytes and a rat model

The environmental neurotoxin β-N-methylamino-L-alanine (BMAA) is a glutamate receptor agonist that can induce oxidative stress and has been implicated as a possible risk factor for neurodegenerative disease. Detection of BMAA in mussels, crustaceans, and fish illustrates that the sources of human exposure to this toxin are more abundant than previously anticipated. The aim of this study was to determine uptake of BMAA in the pineal gland and subsequent effects on melatonin production in primary pinealocyte cultures and a rat model. Autoradiographic imaging of 10-day-old male rats revealed a high and selective uptake in the pineal gland at 30 minutes to 24 hours after ¹⁴ C-L-BMAA administration (0.68 mg/kg). Primary pinealocyte cultures exposed to 0.05-3 mmol/L BMAA showed a 57%-93% decrease in melatonin synthesis in vitro. Both the metabotropic glutamate receptor 3 (mGluR3) antagonist Ly341495 and the protein kinase C (PKC) activator phorbol-12-myristate-13-acetate prevented the decrease in melatonin secretion, suggesting that BMAA inhibits melatonin synthesis by mGluR3 activation and PKC inhibition. Serum analysis revealed a 45% decrease in melatonin concentration in neonatal rats assessed 2 weeks after BMAA administration (460 mg/kg) and confirmed an inhibition of melatonin synthesis in vivo. Given that melatonin is a most important neuroprotective molecule in the brain, the etiology of BMAA-induced neurodegeneration may include mechanisms beyond direct excitotoxicity and oxidative stress.

Factors Associated With Successful MRI Scanning in Unsedated Young Children

Introduction: Young children are often unable to remain still for magnetic resonance imaging (MRI), leading to unusable images. Various preparation methods may increase success, though it is unclear which factors best predict success. Here, in a retrospective sample, we describe factors associated with successful scanning in unsedated young children. We hypothesized that the mock scanner training and fewer behavior problems would result in higher success rates. Methods: We recruited 134 children aged 2.0-5.0 years for an MRI study. We compared success between children whose parents opted for mock scanner training (n = 20) or not (n = 114), and evaluated demographic and cognitive factors that predicted success. Results: Ninety-seven children (72%) completed at least one MRI sequence successfully on their first try; 64 children (48%) provided high-quality data for all 3 structural imaging sequences. Cognitive scores were higher in successful than unsuccessful children. Children who received mock scanner training were no more likely to be successful than children without, though they had slightly higher scores on T1 image quality. Conclusions: Our data shows that scanning with minimial preparation is possible in young children, and suggests limited advantages of mock scanner preparation for healthy young children.Cognitive ability may predict success.

Melatonin versus chloral hydrate as the sedating agent in performing electroencephalogram in paediatric patients

Electroencephalography (EEG) is a valuable tool in the diagnosis of epilepsy. The attainment of a high quality EEG requires patient's co-operation which is particularly difficult in children. Chloral hydrate has been used as a sedating agent in EEGs but it has potential serious adverse effects and anti-epileptic activity. Melatonin is used increasingly in different investigations as a safe alternative. Our study is to compare their effectiveness as sedating agents in performing EEGs and the detection rate of abnormal EEGs. This is a retrospective study performed in a regional hospital in Hong Kong. One hundred and ninety two EEG studies were included from December 2010 to July 2014. One hundred and two children were given chloral hydrate (50 mg/Kg) in the first half of the period and 90 children were given melatonin (3 mg for =< 5 years or 6 mg for >= 5 year) in the later half. The two groups are compared with Pearson's Chi-squared test with Yates’ continuity correction. The successful rate in sedation was similar between the two groups while the pick up rate of abnormal EEGs was 52.56% in the melatonin group and 21.57% in the chloral hydrate group (p < 0.05). Subgroup analysis among patients with epilepsy or mental retardation and intellectual disability shared same findings with higher detection rate of abnormal EEGs in the melatonin group. No side effect was documented in the study. Compare with chloral hydrate, melatonin is a safe and effective alternative and probably has less interference with the electrographic activity.

Efficiency of Melatonin as Compared to Pentobarbital for Audiometry Brainstem Response in Children With Associated Disorders

PURPOSE

Outpatient pediatric audiometry brainstem response (ABR) uses various techniques (no drug, hydroxyzine, pentobarbital, melatonin). The aim of this study was to evaluate the efficiency of melatonin as compared to pentobarbital in children with associated disorders.

METHOD

This was a retrospective study that took place in a tertiary care center. Eighty-three children (34 girls and 49 boys) had performed ABR under pentobarbital (GPent) or melatonin (GMel) between 2013 and 2014 and were included. All children had associated neurological or behavioral disorders or had failed a previous ABR using another technique. Success rate, defined as completed binaural investigation, delay, and duration of sleep (minutes), as well as side effects, were compared between GPent and GMel.

RESULTS

There were 56 patients in GMel and 27 in GPent, with a mean age at test of 3 years and 10 months (1-13 years) and 4 years and 1 month (1-14.5 years), respectively. Success rate was 76.8% and 88.8%, respectively (p > .05), sleep duration was 23 and 153 min (p < .0001), and mean delay was 35 and 54 min. No side effects have been reported.

CONCLUSIONS

Melatonin is a drug widely used, particularly for electroencephalogram in children. Sleep duration allowed a success rate that was comparable to pentobarbital. Melatonin seems to be an efficient alternative to pentobarbital for pediatric ABR.

Paediatric sedation for imaging is safe and effective in a district general hospital

OBJECTIVE

To devise a safe and effective sedation protocol for imaging paediatric patients in a small district general hospital (DGH).

METHODS

Chloral hydrate, alimemazine and learned best practice were used for imaging 105 children between January 2013 and May 2015. We retrospectively reviewed case notes for this time period to establish rates of successful sedation and adverse events.

RESULTS

Scanning was successful in 100/105 (95%) children. No serious adverse events were reported. Non-serious adverse events occurred in eight cases. 12 patients were discharged more than 4 h after scanning owing to prolonged sedation.

CONCLUSION

This is a safe and effective protocol for delivering sedation for imaging in paediatric patients. We would encourage similar centres to adopt this protocol where resources for i.v. sedation and general anaesthesia are limited.

ADVANCES IN KNOWLEDGE

There are many different sedation protocols in the literature for imaging in paediatric patients, with varying levels of success and adverse event rates. We present here a protocol that offers a high efficacy and safe sedation for imaging in a DGH.

A comparison of the effect of two doses of oral melatonin with oral midazolam and placebo on pre-operative anxiety, cognition and psychomotor function in children: A randomised double-blind study

Background and Aims:

Melatonin (MT), a naturally occurring pituitary hormone has a sleep promoting effect. There are very few studies on pre-operative oral MT (0.2–0.5 mg/kg) in children. We planned a study to assess the efficacy of oral MT in two doses and compare it with oral midazolam and placebo for pre-operative anxiolysis, sedation, maintenance of cognition and psychomotor skills, parental separation behaviour and venepuncture compliance.

Methods:

This prospective double-blind randomised study was conducted after ethical committee approval on 100 children aged 5–15 years, American Society of Anaesthesiologists physical status I and II undergoing elective surgery at our hospital from January 1, 2014, to December 31, 2014. Mentally disordered children were excluded from the study. They were randomised into four groups of 25 each (A, B, C, D) to receive either oral MT 0.5 mg/kg or 0.75 mg/kg or oral midazolam 0.5 mg/kg or placebo 45–60 min, respectively, before induction. The child's anxiety, cognition and psychomotor function before and after pre-medication, behaviour during the parental separation and venepuncture were appropriately scored. Kruskal–Wallis analysis of variance for intergroup and Wilcoxon matched pairs tests for intragroup comparisons of data were applied.

Results:

The four groups were comparable regarding mean age, weight and sex. The anxiety score reductions in the three groups when compared to placebo were statistically significant. Children receiving MT 0.75 mg/kg had maximum anxiolysis and venepuncture compliance (P < 0.05). Cognition was decreased with maximum sedation, successful parental separation and psychomotor impairment in the midazolam group (P < 0.05).

Conclusion:

Oral MT (0.5 mg/kg and 0.75 mg/kg) in children decreases pre-operative anxiety without impairing cognitive and psychomotor functions, the 0.75 mg/kg dose being most effective.

Pharmacokinetics of high-dose intravenous melatonin in humans

This crossover study investigated the pharmacokinetics and adverse effects of high-dose intravenous melatonin. Volunteers participated in 3 identical study sessions, receiving an intravenous bolus of 10 mg melatonin, 100 mg melatonin, and placebo. Blood samples were collected at baseline and 0, 60, 120, 180, 240, 300, 360, and 420 minutes after the bolus. Quantitative determination of plasma melatonin concentrations was performed using a radioimmunoassay technique. Pharmacokinetic parameters were estimated by a compartmental pharmacokinetic analysis. Adverse effects included assessments of sedation and registration of other symptoms. Sedation, evaluated as simple reaction times, was measured at baseline and 120, 180, 300, and 420 minutes after the bolus. Twelve male volunteers completed the study. Median (IQR) Cmax after the bolus injections of 10 mg and 100 mg of melatonin were 221,500.0 (185,637.5-326,175.0) pg/mL and 1,251,500.0 (864,375.0-1,770,500.0) pg/mL, respectively; mean (SD) t1/2 was 42.3 (5.6) minutes and 46.2 (6.2) minutes; mean (SD) Vd was 1.6 (0.9) L/kg and 2.0 (0.8) L/kg; mean (SD) CL was 0.0253 (0.0096) L/min · kg and 0.0300 (0.0120) L/min · kg; and median (IQR) AUC0- ∞ , 8,997,633.0 (6,071,696.2-11,602,811.9) pg · min/mL and 54,685,979.4 (36,028,638.6-105,779,612.0) pg · min/mL. High-dose intravenous melatonin did not induce sedation, evaluated as simple reaction times. No adverse effects were reported in the study.

Current role of melatonin in pediatric neurology: clinical recommendations

BACKGROUND/PURPOSE

Melatonin, an indoleamine secreted by the pineal gland, plays a key role in regulating circadian rhythm. It has chronobiotic, antioxidant, anti-inflammatory and free radical scavenging properties.

METHODS

A conference in Rome in 2014 aimed to establish consensus on the roles of melatonin in children and on treatment guidelines.

RESULTS AND CONCLUSION

The best evidence for efficacy is in sleep onset insomnia and delayed sleep phase syndrome. It is most effective when administered 3-5 h before physiological dim light melatonin onset. There is no evidence that extended-release melatonin confers advantage over immediate release. Many children with developmental disorders, such as autism spectrum disorder, attention-deficit/hyperactivity disorder and intellectual disability have sleep disturbance and can benefit from melatonin treatment. Melatonin decreases sleep onset latency and increases total sleep time but does not decrease night awakenings. Decreased CYP 1A2 activity, genetically determined or from concomitant medication, can slow metabolism, with loss of variation in melatonin level and loss of effect. Decreasing the dose can remedy this. Animal work and limited human data suggest that melatonin does not exacerbate seizures and might decrease them. Melatonin has been used successfully in treating headache. Animal work has confirmed a neuroprotective effect of melatonin, suggesting a role in minimising neuronal damage from birth asphyxia; results from human studies are awaited. Melatonin can also be of value in the performance of sleep EEGs and as sedation for brainstem auditory evoked potential assessments. No serious adverse effects of melatonin in humans have been identified.

Analgesic, anxiolytic and anaesthetic effects of melatonin: new potential uses in pediatrics

Exogenous melatonin is used in a number of situations, first and foremost in the treatment of sleep disorders and jet leg. However, the hypnotic, antinociceptive, and anticonvulsant properties of melatonin endow this neurohormone with the profile of a drug that modulates effects of anesthetic agents, supporting its potential use at different stages during anesthetic procedures, in both adults and children. In light of these properties, melatonin has been administered to children undergoing diagnostic procedures requiring sedation or general anesthesia, such as magnetic resonance imaging, auditory brainstem response tests and electroencephalogram. Controversial data support the use of melatonin as anxiolytic and antinociceptive agents in pediatric patients undergoing surgery. The aim of this review was to evaluate available evidence relating to efficacy and safety of melatonin as an analgesic and as a sedative agent in children. Melatonin and its analogs may have a role in antinociceptive therapies and as an alternative to midazolam in premedication of adults and children, although its effectiveness is still controversial and available data are clearly incomplete.

Occurrence of epileptiform discharges and sleep during EEG recordings in children after melatonin intake versus sleep-deprivation

OBJECTIVE

To determine if melatonin is equally efficient as partial sleep deprivation in inducing sleep without interfering with epileptiform discharges in EEG recordings in children 1-16 years old.

METHODS

We retrospectively analysed 129 EEGs recorded after melatonin intake and 113 EEGs recorded after partial sleep deprivation. Comparisons were made concerning occurrence of epileptiform discharges, the number of children who fell asleep and the technical quality of EEG recordings. Comparison between different age groups was also made.

RESULTS

No significant differences were found regarding occurrence of epileptiform discharges (33% after melatonin intake, 36% after sleep deprivation), or proportion of unsuccessful EEGs (8% and 10%, respectively). Melatonin and sleep deprivation were equally efficient in inducing sleep (70% in both groups). Significantly more children aged 1-4 years obtained sleep after melatonin intake in comparison to sleep deprivation (82% vs. 58%, p⩽0.01), and in comparison to older children with melatonin induced sleep (58-67%, p⩽0.05). Sleep deprived children 9-12 years old had higher percentage of epileptiform discharges (62%, p⩽0.05) compared to younger sleep deprived children.

CONCLUSION

Melatonin is equally efficient as partial sleep deprivation to induce sleep and does not affect the occurrence of epileptiform discharges in the EEG recording. Sleep deprivation could still be preferable in older children as melatonin probably has less sleep inducing effect.

SIGNIFICANCE

Melatonin induced sleep have advantages, especially in younger children as they fall asleep easier than after sleep deprivation. The procedure is easier for the parents than keeping a young child awake for half the night.

The role of melatonin in anaesthesia and critical care

Melatonin is a neurohormone secreted by the pineal gland. It is widely present in both plant and animal sources. In several countries, it is sold over the counter as tablets and as food supplement or additive. Currently, it is most often used to prevent jet lag and to induce sleep. It has been and is being used in several clinical trials with different therapeutic approaches. It has sedative, analgesic, anti-inflammatory, anti-oxidative and chronobiotic effects. In the present review, the potential therapeutic benefits of melatonin in anaesthesia and critical care are presented. This article aims to review the physiological properties of melatonin and how these could prove useful for several clinical applications in perioperative management, critical care and pain medicine. The topic was handsearched from textbooks and journals and electronically from PubMed, and Google scholar using text words.

Spica cast as an alternative to general anesthesia for lower limb MRI in young children

Background

The conventional approach for MRI procedures in very young children is to use general anesthesia which comes with inherent risks. Non-pharmacological strategies to reduce anxiety in children have also been described, but they all require patient cooperation. The purpose of the study was to evaluate the ability to complete diagnosis using temporary spica cast immobilization (TSCI) in children less than 3 years old undergoing MRI procedures for lower limb disorders.

Materials and methods

A retrospective review identified 14 children under 3 years old that had required an MRI for a lower limb disorder, using TSCI. The MRI procedure was performed for evaluation of hip dysplasia, bone infections, limping, evaluation of soft tissue tumor and femoral head osteonecrosis. A spica cast was fitted by the pediatric orthopedic team. The MRI procedure was subsequently performed.

Results

Diagnosis was achieved in all cases. The radiologist identified movement artifacts (14 %) that did not impair the image quality enough to prevent interpretation.

Conclusion

TSCI is a safe, effective and costless procedure avoiding general anesthesia for young patients under 3 years old who require MRI for pelvis or lower limb disorders.

Level of evidence

IV.

Steal induction in preschool children: is melatonin as good as clonidine? A prospective, randomized study

OBJECTIVES/AIMS

To investigate whether melatonin would be an alternative drug to clonidine for performance of steal induction.

BACKGROUND

Distress during induction might have a negative impact on postoperative behavior. A steal induction is a technique for smooth anesthesia induction, and clonidine has been the primary agent for this purpose. There are conflicting results regarding the efficacy of melatonin for premedication, but its sleep inducing properties have been shown in children.

METHODS

Pediatric patients ASA I and II were randomly assigned to receive either melatonin 0.3 mg·kg(-1) or clonidine 4 μg·kg(-1) orally. Primary outcome was the percentage of successful steal induction, while secondary outcomes were onset of sleep, overall quality of mask induction, and adverse events at emergence from anesthesia.

RESULTS

A total of 87 patients were included for analysis with a median age of 33 months (range, 12-71) and median weight of 14 kg (range, 8-26). A successful steal induction was performed in 88.4% of group C and 75% of group M (P > 0.05). Onset of sleep in these patients occurred after a median time of 45 min (range 10-60) in group C and 35 min (range 15-60) in group M (P > 0.05). Children not falling asleep after melatonin received the premedication at a significantly earlier time point compared to those falling asleep (P = 0.001).

CONCLUSIONS

Melatonin was effective for steal induction in 75% of children compared to 88% of children who had clonidine. Melatonin resulted less effective when administered early in the morning.

Whole body muscle MRI protocol: pattern recognition in early onset NM disorders

A paediatric and adult whole-body MRI (WB-MRI) protocol using a 1.5-T MRI system was used to examine 117 individuals (106 patients, 11 asymptomatic relatives). Genetic diagnosis was obtained in 38 subjects (RYR1, LMNA, COL6, DNM2, GAA, TPM2, SGCA, MYH7, NEB, SMN, FKBP14). T1-TSE WB-MRI sequences were abnormal in 67% of patients and 27% of asymptomatic relatives. Multiple striped signal abnormalities ('tiger-like') were very specific for COLVI-related myopathy. Distinct involvement of muscles in the head, neck, trunk, girdles and limbs was observed in patients with RYR1, SEPN1, GAA, LMNA or TPM2 mutations. Abnormalities and pattern recognition were more frequent in patients studied due to rigid spine syndrome (80% abnormal, recognisable in 75% of cases), hyperlaxity syndrome (75%; 50%) or with confirmed myopathy but absence of these markers (71%; 40%). Pattern was consistent with the molecular diagnosis in 97%. Mild clinical involvement was revealed by muscle testing in three parents with abnormal WB-MRI. The Garches WB-MRI protocol is suitable for a large spectrum of adults and children with early-onset neuromuscular disorders and can be used as an effective screening test in relatives. Recognition of characteristic patterns of abnormalities is improved by whole-body scanning compared with sequential MRI and, therefore, diagnostic impact is greater.

Melatonin utility in neonates and children

Melatonin (N-acetyl-5-methoxytryptamine) is an endogenously produced indoleamine secreted by the pineal gland and the secretion is suppressed by light. Melatonin is a highly effective antioxidant, free radical scavenger, and has anti-inflammatory effect. Plenty of evidence supports the utility of melatonin in adults for cancer, neurodegenerative disorders, and aging. In children and neonates, melatonin has been used widely, including for respiratory distress syndrome, bronchopulmonary dysplasia, periventricular leukomalacia (PVL), hypoxia-ischemia encephalopathy and sepsis. In addition, melatonin can be used in childhood sleep and seizure disorders, and in neonates and children receiving surgery. This review article discusses the utility of melatonin in neonates and children.

Paediatric MRI under sedation: is it necessary? What is the evidence for the alternatives?

To achieve diagnostic images during MRI examinations, small children need to lie still to avoid movement artefact. To reduce patient motion, obviate the need for voluntary immobilisation or breath-holding and therefore obtain high-quality images, MRI of infants is frequently carried out under sedation or general anaesthesia, but this is not without risk and expense. However, many other techniques are available for preparing children for MRI, which have not been fully evaluated. Here, we evaluate the advantages and disadvantage of sedation and anaesthesia for MRI. We then evaluate the alternatives, which include neonatal comforting techniques, sleep manipulation, and appropriate adaptation of the physical environment. We summarize the evidence for their use according to an established hierarchy. Lastly, we discuss several factors that will influence the choice of imaging preparation, including patient factors, imaging factors and service provision. The choice of approach to paediatric MRI is multi-factorial, with limited scientific evidence for many of the current approaches. These considerations may enable others to image children using MRI under different circumstances.

Clinical uses of melatonin in pediatrics

This study analyzes the results of clinical trials of treatments with melatonin conducted in children, mostly focused on sleep disorders of different origin. Melatonin is beneficial not only in the treatment of dyssomnias, especially delayed sleep phase syndrome, but also on sleep disorders present in children with attention-deficit hyperactivity, autism spectrum disorders, and, in general, in all sleep disturbances associated with mental, neurologic, or other medical disorders. Sedative properties of melatonin have been used in diagnostic situations requiring sedation or as a premedicant in children undergoing anesthetic procedures. Epilepsy and febrile seizures are also susceptible to treatment with melatonin, alone or associated with conventional antiepileptic drugs. Melatonin has been also used to prevent the progression in some cases of adolescent idiopathic scoliosis. In newborns, and particularly those delivered preterm, melatonin has been used to reduce oxidative stress associated with sepsis, asphyxia, respiratory distress, or surgical stress. Finally, the administration of melatonin, melatonin analogues, or melatonin precursors to the infants through the breast-feeding, or by milk formula adapted for day and night, improves their nocturnal sleep. Side effects of melatonin treatments in children have not been reported. Although the above-described results are promising, specific studies to resolve the problem of dosage, formulations, and length of treatment are necessary.

Perioperative melatonin use

Melatonin is a substance chiefly produced by the pineal gland and has a key role in the sleep-wake cycle. It also has an important antioxidant role. Exogenous melatonin has a short half-life and is available in a range of preparations. Newer analogues targeted for the recently discovered melatonin MT1 and MT2 receptors have also been developed. Exogenous melatonin is used as a resynchronisation agent in jet lag and for other sleep disturbances. Perioperatively, melatonin has been used as a premedicant, sedative and analgesic. It decreases paediatric emergence delirium. The antioxidant properties of melatonin are being investigated for use in sepsis and reperfusion injuries. It would appear that patients on melatonin supplements should continue taking them perioperatively because there may be benefits. Melatonin and its analogues will be increasingly encountered in the perioperative setting.

Update on the use of melatonin in pediatrics

Melatonin, an endogenously produced indoleamine, is a highly effective antioxidant, free radical scavenger, and a primary circadian regulator. Melatonin has important antioxidant properties owing to direct and indirect effects. It directly scavenges reactive oxygen and reactive nitrogen species, prevents molecular oxidation, improves mitochondrial physiology, and restores glutathione homeostasis. Its indirect antioxidant effects stem from its ability to stimulate the activities of the enzymes involved in the glutathione cycling and production. Melatonin, by reducing free radical damage, may be an effective protective agent for the fetus as it is in adults. Several clinical studies on melatonin have shown that it reduces oxidative stress in human newborns with sepsis, hypoxic distress, or other conditions, where there is excessive free radical generation. A role of melatonin in infant development has also been suggested. Pineal dysfunction may be associated with deleterious outcomes in infants and may contribute to an increased prevalence of sudden infant death syndrome. Delayed melatonin production is evident in infants who had experienced an apparent life-threatening event. Melatonin has been used as a pharmacologic treatment for insomnias associated with shift work, jet lag, and delayed sleep onset in adults for decades. In children as well, melatonin has value as a sleep-promoting agent. Evidence suggests that melatonin has utility as an analgesic agent presumably related to its ability to release β-endorphin. The data support the notion that melatonin, or one of its analogs, might find use as an anesthetic agent in children.

Preparing children with a mock scanner training protocol results in high quality structural and functional MRI scans

We evaluated the use of a mock scanner training protocol as an alternative for sedation and for preparing young children for (functional) magnetic resonance imaging (MRI). Children with severe mental retardation or developmental disorders were excluded. A group of 90 children (median age 6.5 years, range 3.65-14.5 years) participated in this study. Children were referred to the actual MRI investigation only when they passed the training. We assessed the pass rate of the mock scanner training sessions. In addition, the quality of both structural and functional MRI (fMRI) scans was rated on a semi-quantitative scale. The overall pass rate of the mock scanner training sessions was 85/90. Structural scans of diagnostic quality were obtained in 81/90 children, and fMRI scans with sufficient quality for further analysis were obtained in 30/43 of the children. Even in children under 7 years of age, who are generally sedated, the success rate of structural scans with diagnostic quality was 53/60. FMRI scans with sufficient quality were obtained in 23/36 of the children in this younger age group. The association between age and proportion of children with fMRI scans of sufficient quality was not statistically significant. We conclude that a mock MRI scanner training protocol can be useful to prepare children for a diagnostic MRI scan. It may reduce the need for sedation in young children undergoing MRI. Our protocol is also effective in preparing young children to participate in fMRI investigations.