Factors Affecting Sleep Among Dogs and Cats in a Veterinary Intensive Care Unit.

Objective: To evaluate the amount of sleep obtained by hospitalized dogs and cats in an intensive care setting and to identify factors that may impact veterinary patients' sleep.

Design: A prospective, observational study spanning a 4-week period in June of 2020.

Setting: Academic teaching hospital.

Animals: A total of 96 dogs and 16 cats hospitalized in the ICU during the 4-week study period.

Interventions: None.

Measurements and main results: Patient activity was categorized as active, resting, or asleep and was recorded along with ICU environmental data on an hourly basis. Environmental data consisted of subjective assessment of noise level, ambient lighting, number of people present, and number of hospitalized patients. The median observed time asleep was 40% and 11% for dogs and cats, respectively. During natural nighttime hours (9:00 p.m. to 6:00 a.m.), the odds of a patient being asleep were 1.7 times higher if lights were dimmed (p < 0.001). Patients were also less likely to be asleep with higher noise levels (odds ratio 0.66 for each increase in noise level, p = 0.003).

Conclusions: Hospitalized dogs and cats experience sleep disturbances similar to those reported in human ICU patients. Ambient noise and light are significant factors contributing to sleep disruption in cats and dogs hospitalized in a veterinary ICU. The findings of this study support implementing efforts to promote patient sleep through environmental modifications in the veterinary intensive care setting. Additional research is needed to establish objective means of assessing sleep in hospitalized dogs and cats, to determine sleep patterns of hospitalized veterinary patients, and to quantify the impact of sleep disturbances on veterinary patient convalescence.