Melatonin as a sedation substitute for diagnostic procedures: MRI and EEG

Efficiency of Melatonin as a Sedative for Auditory Brainstem Response in Children

Introduction-Although auditory brainstem response (ABR) testing is among the most frequently used investigations in pediatric audiology and it often requires sedation or general anesthesia. In recent years, melatonin has been successfully used as an alternative way of inducing sleep, particularly in children undergoing magnetic resonance imaging (MRI) or electroencephalography (EEG). Purpose-To assess the effectiveness of orally administered melatonin as an alternative to sedation or general anesthesia during ABR testing. Method-In total, 33 children with suspected hearing loss underwent ABR tests in melatonin-induced sleep. Each patient received an initial dose of 5 mg, which was re-administered in case of failure to obtain sleep. Click-induced ABR tests were performed on both ears. Results-ABR tests were successfully performed in 72.7% of the patients. The average total length of time needed to obtain sleep and complete the ABR testing was 45 min. There was no significant difference between the patients who completed the examination and those who did not in terms of age or psychomotor development. There was a statistically significant association between receiving a maintenance dose and successful completion of the test (p < 0.001). There was also a significant connection between the degree of hearing loss and the success rate of the ABR tests (p < 0.001). Conclusions-Melatonin-induced sleep is a good and safer alternative to anesthesia to perform ABR testing in young children. It is easily administered, tolerated by the patients, and accepted by parents.

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.

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.

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.

Analysis of Different Melatonin Secretion Patterns in Children With Sleep Disorders: Melatonin Secretion Patterns in Children

The objective of this study was to analyze circadian patterns of urinary 6-sulphatoxymelatonin (aMT6s) excretion in children with primary sleep disorders in comparison with healthy controls. A total of 124 control children and 124 patients (aged 4-14 years) diagnosed with diverse primary sleep disorders were recruited. aMT6s concentrations were measured in diurnal and nocturnal urine, as well as in 24-hour urine. aMT6s levels were significantly higher and showed significantly more evident circadian variations in the control group ( P < .001). Four different melatonin (aMT) production and excretion patterns were distinguished in the group with sleep disorders: (1) standard aMT production pattern, (2) low aMT production pattern, (3) aMT production pattern with absence of circadian variation, and (4) aMT hyperproduction pattern. This study highlights the importance of analyzing specific alterations of aMT secretion in each sleep disorder and provides evidences to explain why not all children with sleep disturbances do respond to aMT treatment.

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.

[French guidelines on electroencephalogram]

Electroencephalography allows the functional analysis of electrical brain cortical activity and is the gold standard for analyzing electrophysiological processes involved in epilepsy but also in several other dysfunctions of the central nervous system. Morphological imaging yields complementary data, yet it cannot replace the essential functional analysis tool that is EEG. Furthermore, EEG has the great advantage of being non-invasive, easy to perform and allows control tests when follow-up is necessary, even at the patient's bedside. Faced with the advances in knowledge, techniques and indications, the Société de Neurophysiologie Clinique de Langue Française (SNCLF) and the Ligue Française Contre l'Épilepsie (LFCE) found it necessary to provide an update on EEG recommendations. This article will review the methodology applied to this work, refine the various topics detailed in the following chapters. It will go over the summary of recommendations for each of these chapters and underline proposals for writing an EEG report. Some questions could not be answered by the review of the literature; in those cases, an expert advice was given by the working and reading groups in addition to the guidelines.

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.

The effect of melatonin on sedation of children undergoing magnetic resonance imaging

BACKGROUND

Melatonin may induce a natural sleepiness and improve predictability of sedation drugs. We have investigated its clinical value in children sedated for magnetic resonance imaging.

METHODS

In a stratified randomized double-blind study, 98 children received either melatonin or placebo 10 min before they were sedated with a standard oral regimen. Children >5 and <15 kg received chloral hydrate and those >or=15 and <40 kg had a combination of temazepam with droperidol (T&D). The doses of melatonin were 3 and 6 mg, respectively. One observer recorded the time taken to reach criteria for deep sedation, sedation failure and other sedation-related events.

RESULTS

In the chloral hydrate group (n=50) 50% were deeply sedated by 31 min after melatonin and 40 min after placebo (P=0.57). There were zero and 1 failures, respectively. The geometric mean time taken to reach deep sedation was 39 min in both subgroups. In the T&D group (n=48) 50% were deeply sedated by 70 min in both subgroups (two failures in each); geometric mean times were 68 and 71 min, respectively (P=0.58). Children closed their eyes slightly earlier after melatonin (respective geometric means 42 vs 48, P=0.17), and took slightly longer to achieve discharge criteria (146 vs 135, P=0.47).

CONCLUSION

In these doses and clinical conditions, melatonin did not contribute to sedation of children.

Sedation for procedures in children: a guide for the non-anaesthetist

The aim of this review is to provide a succinct guide to sedation of children for procedures. Uncooperative children are notoriously hard to sedate and the choice of appropriate technique depends upon the intended procedure. It is too easy to exceed safe dose limits and cause airway obstruction or respiratory depression. ‘Sedationists’ must remember that safety is paramount; they must receive training and work within protocols. Published guidelines are available.

The management of infants and children for painless imaging

The ability of a child to remain sufficiently immobile for painless imaging depends upon their behaviour and the imaging itself. Anaesthesia allows imaging to be optimised but it is expensive, scarce and inappropriate for many situations. Fortunately, sedation and behavioural techniques are sufficiently successful for the majority of scanning, and success rates are high provided that suitable children are selected. Sedation, however, administered by non-anaesthetists, may have catastrophic complications such as airway obstruction. Current UK recommendations demand that any sedation technique has a 'wide margin of safety', but in addition to this, safety is dependent on trained, skillful and experienced staff. Magnetic resonance imaging frightens many children and special planning is necessary for sedation and anaesthesia. When planning an imaging service for children, all the management techniques should be considered in order to achieve maximum efficiency, quality and safety.