The effect of melatonin on reduction in the need for sedative agents and duration of mechanical ventilation in traumatic intracranial hemorrhage patients: a randomized controlled trial

Pharmacologic Sleep Aids in the Intensive Care Unit: A Systematic Review

Background: Patients in the intensive care unit (ICU) often experience poor sleep quality. Pharmacologic sleep aids are frequently used as primary or adjunctive therapy to improve sleep, although their benefits in the ICU remain uncertain. This review aims to provide a comprehensive assessment of the objective and subjective effects of medications used for sleep in the ICU, as well as their adverse effects. Methods: PubMed, Web of Science, Scopus, Embase, and Cochrane Central Register of Controlled Trials were systematically searched from their inception until June 2023 for comparative studies assessing the effects of pharmacologic sleep aids on objective and subjective metrics of sleep. Results: Thirty-four studies with 3498 participants were included. Medications evaluated were melatonin, ramelteon, suvorexant, propofol, and dexmedetomidine. The majority of studies were randomized controlled trials. Melatonin and dexmedetomidine were the best studied agents. Objective sleep metrics included polysomnography (PSG), electroencephalography (EEG), bispectral index, and actigraphy. Subjective outcome measures included patient questionnaires and nursing observations. Evidence for melatonin as a sleep aid in the ICU was mixed but largely not supportive for improving sleep. Evidence for ramelteon, suvorexant, and propofol was too limited to offer definitive recommendations. Both objective and subjective data supported dexmedetomidine as an effective sleep aid in the ICU, with PSG/EEG in 303 ICU patients demonstrating increased sleep duration and efficiency, decreased arousal index, decreased percentage of stage N1 sleep, and increased absolute and percentage of stage N2 sleep. Mild bradycardia and hypotension were reported as side effects of dexmedetomidine, whereas the other medications were reported to be safe. Several ongoing studies have not yet been published, mostly on melatonin and dexmedetomidine. Conclusions: While definitive conclusions cannot be made for most medications, dexmedetomidine improved sleep quantity and quality in the ICU. These benefits need to be balanced with possible hemodynamic side effects.

Prophylactic Melatonin for Delirium in Intensive Care Unit: An Updated Systematic Review and Meta-analysis of Randomized Controlled Trials

Introduction

Delirium, being a common disorder among critically ill patients, has a reported incidence ranging 45-83% in the intensive care unit (ICU) population. The prophylactic use of melatonin and melatonergics has been shown to have a positive effect in reducing the incidence of delirium in many clinical trials. Our study was thus proposed to find out the role of melatonin on the incidence and severity of ICU delirium, ICU and hospital length of stay (LOS), requirement, duration of mechanical ventilation, and ICU mortality.

Methodology

A systematic search of various databases was performed to find out the trials which compare melatonin with a placebo or standard therapy for delirium prevention with the results conveyed as mean differences (MDs) or risk ratios. The statistical software, Review Manager (RevMan, version 5.4), was used for data synthesis.

Results

Twelve studies were included in the meta-analysis. Prophylactic administration of melatonin or ramelteon was not associated with a statistically significant reduction in the incidence of delirium (odds ratio [OR] 0.63; confidence interval [CI]: 0.60, 1.32; p = 0.22), the severity of delirium (MD: 0.22; 95% CI: From -1.36 to 1.81; p = 0.78), ICU LOS (MD: 0.05; 95% CI: From -0.65 to 0.75; p = 0.89), hospital LOS (MD: -1.46; 95% CI: From -4.50 to -1.59; p = 0.35), need for mechanical ventilation (OR: 0.74, 95% CI: 0.38-1.44; p = 0.37), and ICU mortality (MD: 0.78; 95% CI: 0.56; 1.11; p = 0.62). However, a significant reduction in the duration of mechanical ventilation (MD: -0.85; 95% CI: From -1.64 to -0.06; p = 0.03) was found.

Conclusion

Our meta-analysis suggests that melatonin when given prophylactically has no significant role in reducing the incidence and severity of delirium, ICU and hospital LOS, need for mechanical ventilation, duration of mechanical ventilation, and ICU mortality. Further studies are warranted.

How to cite this article

Mukundarajan R, Soni KD, Trikha A. Prophylactic Melatonin for Delirium in Intensive Care Unit: An Updated Systematic Review and Meta-analysis of Randomized Controlled Trials. Indian J Crit Care Med 2023;27(9):675-685.

Effects of Melatonin Administration on Post-Stroke Delirium in Patients with Intracerebral Hemorrhage

Post-stroke delirium (PSD) after intracerebral hemorrhage (ICH) is considered to be even more detrimental compared to that after ischemic stroke. Treatment options for post-ICH PSD remain limited. This study aimed at investigating to what extent prophylactic melatonin administration may have beneficial effects on post-ICH PSD. We performed a mono-centric, non-randomized, non-blinded, prospective cohort study, including 339 consecutive ICH patients admitted to the Stroke Unit (SU) from December 2015 to December 2020. The cohort consisted of ICH patients who underwent standard care (defined as the control group) and ICH patients who additionally received prophylactic melatonin (2 mg per day, at night) within 24 h of ICH onset until the discharge from the SU. The primary endpoint was post-ICH PSD prevalence. The secondary endpoints were: (i) PSD duration and (ii) the duration of SU stay. The PSD prevalence was higher in the melatonin treated cohort compared to the propensity score-matched (PSM) control group. Post-ICH PSD patients receiving melatonin had shorter SU-stay durations, and shorter PSD durations, although not statistically significant. This study shows no efficacy in limiting post-ICH PSD with preventive melatonin administration.

Melatonin or Ramelteon for Delirium Prevention in the Intensive Care Unit: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Melatonin modulates the circadian rhythm and has been studied as a preventive measure against the development of delirium in hospitalized patients. Such an effect may be more evident in patients admitted to the ICU, but findings from the literature are conflicting. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs). We assessed whether melatonin or ramelteon (melatonin agonist) reduce delirium incidence as compared to a placebo in ICU patients. Secondary outcomes were ICU length of stay, duration of mechanical ventilation (MV) and mortality. Estimates are presented as risk ratio (RR) or mean differences (MD) with 95% confidence interval (CI). Nine RCTs were included, six of them reporting delirium incidence. Neither melatonin nor ramelteon reduced delirium incidence (RR 0.76 (0.54, 1.07), p = 0.12; I² = 64%), although a sensitivity analysis conducted adding other four studies showed a reduction in the risk of delirium (RR = 0.67 (95%CI 0.48, 0.92), p = 0.01; I² = 67). Among the secondary outcomes, we found a trend towards a reduction in the duration of MV (MD -2.80 (-6.06, 0.47), p = 0.09; I² = 94%) but no differences in ICU-LOS (MD -0.26 (95%CI -0.89, 0.37), p = 0.42; I² = 75%) and mortality (RR = 0.85 (95%CI 0.63, 1.15), p = 0.30; I² = 0%). Melatonin and ramelteon do not seem to reduce delirium incidence in ICU patients but evidence is weak. More studies are needed to confirm this finding.

Melatonin as an Antioxidant Agent in Stroke: An Updated Review

Stroke is a devastating disease associated with high mortality and disability worldwide, and is generally classified as ischemic or hemorrhagic, which share certain similar pathophysiological processes. Oxidative stress is a critical factor involved in stroke-induced injury, which not only directly damages brain tissue, but also enhances a series of pathological signaling cascades, contributing to inflammation, brain edema, and neuronal death. To alleviate these serious secondary brain injuries, neuroprotective agents targeting oxidative stress inhibition may serve as a promising treatment strategy. Melatonin is a hormone secreted by the pineal gland, and has various properties, such as antioxidation, anti-inflammation, circadian rhythm modulation, and promotion of tissue regeneration. Numerous animal experiments studying stroke have confirmed that melatonin exerts considerable neuroprotective effects, partially via anti-oxidative stress. In this review, we introduce the possible role of melatonin as an antioxidant in the treatment of stroke based on the latest published studies of animal experiments and clinical research.

Possible Application of Melatonin in Long COVID

Clinical sequelae and symptoms for a considerable number of COVID-19 patients can linger for months beyond the acute stage of SARS-CoV-2 infection, "long COVID". Among the long-term consequences of SARS-CoV-2 infection, cognitive issues (especially memory loss or "brain fog"), chronic fatigue, myalgia, and muscular weakness resembling myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) are of importance. Melatonin may be particularly effective at reducing the signs and symptoms of SARS-CoV-2 infection due to its functions as an antioxidant, anti-inflammatory, and immuno-modulatory agent. Melatonin is also a chronobiotic medication effective in treating delirium and restoring the circadian imbalance seen in COVID patients in the intensive care unit. Additionally, as a cytoprotector, melatonin aids in the prevention of several COVID-19 comorbidities, including diabetes, metabolic syndrome, and ischemic and non-ischemic cardiovascular diseases. This narrative review discusses the application of melatonin as a neuroprotective agent to control cognitive deterioration ("brain fog") and pain in the ME/CFS syndrome-like documented in long COVID. Further studies on the therapeutic use of melatonin in the neurological sequelae of SARS-CoV-2 infection are warranted.

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.

The use of melatonin in Danish intensive care departments-A nationwide observational study

BACKGROUND

Melatonin is widely employed as a hypnotic in various patient groups. In intensive care patients, melatonin seems to be increasingly used due to potential clinical effects and a favourable safety profile.

OBJECTIVES

We aimed to investigate the extend of usage and clinical practice of melatonin therapy in intensive care departments in Denmark.

DESIGN

Data from regional hospital pharmacies and the Danish Intensive Care Database were used to estimate defined daily dose and defined daily dose per 1000 ICU admission days. Also, related expenses in the period 2015-2019. Finally, a questionnaire describing the clinical practice of melatonin therapy was provided to all Danish intensive care departments.

PRINCIPAL OBSERVATIONS

The usage of melatonin in intensive care departments in Denmark increased from 21,300 DDD (200.0 DDD per 1000 ICU admission days) in 2015 to 52,170 DDD (560.7 DDD per 1000 ICU admission days) in 2019. A total of 32 ICU departments participated in the study (97% of all Danish ICU departments). All included ICU departments employed melatonin as a hypnotic. Nineteen percent of included departments administered melatonin to all admitted patients, whereas 25% of departments rarely administered melatonin. Magistral melatonin 3-mg tablets was the most employed drug dose/formulation. Increased doses of melatonin were administered in selected patients. Melatonin was considered safe by prescribing clinicians.

CONCLUSIONS

Melatonin is widely and increasingly used in Danish intensive care departments. The more than doubled usage of melatonin in the study period advocates for further studies employing validated outcomes of sleep and other patient-relevant outcomes.

EDITORIAL COMMENT

This study documents that melatonin is frequently used as a hypnotic in Danish intensive care units during recent years despite a shortage of reliable evidence to support a recommendation to treat with melatonin in this context. These results support a need for conducting clinical trials to determine whether or not there is a beneficial effect of melatonin treatment in critically ill patients.

Effect of melatonin on stress-induced hyperglycemia and insulin resistance in critically-ill patients: A randomized double-blind, placebo-controlled clinical trial

BACKGROUND

Hyperglycemia is a common finding which is associated with increased mortality and morbidity among critically ill patients. There is currently no evidence that melatonin could improve stress induced hyperglycemia (SIH). In this study, we evaluated the effect of melatonin on blood sugar and insulin resistance (IR) in critically-ill patients.

METHODS

104 critically-ill patients with SIH divided into two groups, receiving melatonin (6 mg BD for 3 days) or placebo. Changes of blood sugar, IR indices including homeostasis model assessment for insulin resistance and homeostasis model assessment adiponectin (HOMA-AD) ratios, Glasgow coma scale (GCS) were evaluated on the 4th day of melatonin prescription. On the 7Th day of study, changes of ventilator dependency and delirium were considered. Mortality and intensive care unit (ICU) stay were also compared between groups.

RESULTS

On day 4, patients in the melatonin group had significantly lower blood glucose and HMOA-IR level compared with the placebo group (P=0.04 and P=0.03, respectively) whereas HOMA-AD level did not differ significantly from placebo group (p>0.2). Also, we did not observe any significant difference in GCS level at this time between groups (p>0.2). On day 7, melatonin could not improve ventilator dependency and delirium significantly (p>0.2) and also could not reduce mortality and ICU stay in comparison with placebo (p>0.2, P=0.2, respectively).

CONCLUSION

Melatonin supplementation showed positive effect on blood sugar and somehow insulin resistance whereas it could not improve ICU complications.