Randomized, Controlled, Double Blind Trial to Evaluate Sedation and Quality of Life in High-risk, Critically Ill Patients Treated With Oral Melatonin

The physiological secretion of such melatonin follows a circadian rhythm: melatonin plasma concentration increases with the dark reaching a peak around to midnight and then gradually decreases (Reiter, 1996; Shigeta et al., 2001; Kunz et al., 2004; Brzezinski et al., 2005).

Administration of oral melatonin could be useful in critically ill high-risk patients in Intensive Care Units because these patients are often suffering from sleep disturbances (Weber et al., 1985; Bourne and Mills, 2004) possibly because of:

• presence of underlying pathology with pain and anxiety,
• presence of oral or nasal respiratory prosthesis,
• execution of therapeutic procedures on 24 h. Moreover it has been demonstrated that in ICU patients melatonin rhythm is desynchronized (Bourne and Mills, 2000). This is probably related to sedation and-or mechanical ventilation. Furthermore, it has been showed that melatonin is a powerful anti-oxidant, therefore it could be potentially useful in critical patients usually characterized by increased production of oxygen free radicals.

AIM OF THE STUDY The study is aimed to estimate if the administration of oral melatonin in ICU patients is able to regularize the sleep-waking rhythm, improving sleep quality and reducing episodes of agitation/mental confusion. The main objectives are: assessment of sleep quality, prevalence of mental confusion/agitation, amount of daily sedative drugs administered and modification of redox status.

ENROLLMENT OF PATIENTS At the admission in ICU, obtained the informed consent, the patients will be randomly assigned to the "Treatment" group receiving melatonin 3mg BID by oral route (or nasogastric tube) or to the "Control" group receiving placebo. The sedation will be performed according to clinical standard.