A multicentre point prevalence study of nocturnal hours awake and enteral pharmacological sleep aids in patients admitted to Australian and New Zealand intensive care units

Objective: Critically ill patients suffer disrupted sleep. Hypnotic medications may improve sleep; however, local epidemiological data regarding the amount of nocturnal time awake and the use of such medications is needed. Design: Point prevalence study. Setting: Adult ICUs in Australia and New Zealand. Participants: All adult patients admitted to participating Intensive Care Units (ICUs) on the study day. Main outcome measures: Time awake overnight (22:00–06:00) was determined by structured nurse observation. The use of enterally administered sedative-hypnotic drugs prior to and during ICU admission was recorded, as was the use of a unit policy and non-pharmacological sleep promotion strategies. Results: Data were available for 532 patients admitted to 40 ICUs (median age 60 years, 336 (63.2%) male, and 222 (41.7%) invasively ventilated). Forty-eight patients (9.0%) received an enteral pharmacological sleep aid, of which melatonin (28, 5.2%) was most frequently used. Patients not invasively ventilated were observed to be awake overnight for a median of 4.0 h (interquartile range (IQR): 2.5, 5.5), with no difference in those receiving an enteral hypnotic (p = 0.9). Non-pharmacological sleep aids were reportedly not offered or available for 52% (earplugs) and 63% of patients (eye masks). Only 7 (17.5%) participating ICUs had a policy informing sleep-optimising interventions. Conclusions: Patients not receiving invasive ventilation appeared to spend many nocturnal hours awake. Pharmacological sleep aid administration was not associated with a greater observed time asleep. Most patients did not receive any non-pharmacological aid, and most ICUs did not have a local guideline or unit policy on sleep promotion.