Sleep deprivation is extremely common in the intensive care unit (ICU), and
this lack of sleep is associated with low melatonin secretion. The objecti
ve of the current study was to explore the effect of exogenous melatonin ad
ministration on sleep quality in patients hospitalized in the pulmonary int
ensive care unit (ICU). We performed a double-blind, placebo-controlled stu
dy in the pulmonary ICU of a tertiary care hospital. Eight adult patients h
ospitalized in the pulmonary ICU with respiratory failure caused by exacerb
ation of chronic obstructive pulmonary disease (COPD) or with pneumonia wer
e studied. Patients received either 3 mg of controlled-release melatonin or
a placebo at 22:00, and sleep quality was evaluated by wrist actigraphy. T
reatment with controlled-release melatonin dramatically improved both the d
uration and quality of sleep in this group of patients. Our results suggest
that melatonin administration to patients in intensive care units may be i
ndicated as a treatment for sleep induction and resynchronization of the "b
iologic clock." This treatment may also help in the prevention of the "ICU
syndrome" and accelerate the healing process.