L. Shilo et al., Patients in the intensive care unit suffer from severe lack of sleep associated with loss of normal melatonin secretion pattern, AM J MED SC, 317(5), 1999, pp. 278-281
Citations number
17
Categorie Soggetti
General & Internal Medicine","Medical Research General Topics
Background: Patients hospitalized in the intensive care unit (ICU) tend to
become agitated and confused, and many even develop temporary psychoses (th
e ICU syndrome). We wondered whether the regulation of sleep and the secret
ion of melatonin is abnormal in ICU patients. Therefore, we studied the ass
ociation of sleep-wake pattern in patients hospitalized in the ICU, their m
elatonin secretion rates, and profile compared with a control group of pati
ents in general medical wards.
Methods: Sleep was assessed by actigraphy. Urine was collected every 3 hour
s for 24 hours. Melatonin secretion was assessed by measuring the melatonin
metabolite 6-sulphatoxy-melatonin by enzyme-linked immunosorbent assay.
Results: Actigraphy suggested that the ICU patients lacked normal sleep beh
avior for the entire study period, except for occasional short naps. Compar
ed with controls, the nocturnal peak of melatonin secretion was absent, exc
ept in two patients in the nonventilated group, and showed a flat curve.
Conclusions: Our results suggest that lack of sleep is indeed a severe prob
lem in ICU patients and is accompanied by impairment of normal melatonin se
cretion. The possibility that melatonin administration may prove useful in
improving sleep patterns in ICU patients deserves further study.