CLINICIAN’S CAPSULE
What is known about the topic?
Most hospital settings do not provide an optimal environment for sleep.
What did this study ask?
Assessed the subjective quality of nighttime sleep and its affecting factors in the emergency department (ED).
What did this study find?
Subjective sleep quality was lower in the ED, as compared with home sleep, and was affected by stress, noise, pain, and stretcher comfort.
Why does this study matter to clinicians?
ED sleep is not optimal but can be improved, as the factors disturbing it are potentially modifiable.
INTRODUCTION
Sleep contributes to several physiological functions, notably the immune, cardiovascular, metabolic, and endocrine systems.Reference Aldabal and Bahammam 1 , Reference Murali, Svatikova and Somers 2 However, most hospitals do not provide an optimal environment for patient sleep quality, which may negatively impact recovery. For example, disrupted sleep has been associated with increased morbidity and mortality in intensive care unit (ICU) patients.Reference Pulak and Jensen 3 In the ICU, polysomnographic studies indicate that nighttime sleep is short, fragmented by many wakefulness periods, composed of predominantly lighter sleep stages (1 and 2), and with almost no restorative slow-wave sleep.Reference Pulak and Jensen 3 - Reference Elliott, McKinley, Cistulli and Fien 5 In general hospital units, a significant proportion of patients (46%–91%) also experience poor subjective sleep quality, as assessed with in-house sleep questionnaires or the Pittsburgh Sleep Quality Index.Reference Javadi, Darvishpour, Mehrdad and Lakeh 6 - Reference Yilmaz, Sayin and Gurler 10
The most frequent factors associated with poor sleep in the ICU or hospital units are age, sex, smoking, anxiety, pain, noise, lighting, worries about their disease, other patients, staff disruption, medical equipment, medication, the illness itself, and bed comfort.Reference Pulak and Jensen 3 - Reference Yilmaz, Sayin and Gurler 10 Fortunately, some recent interventions have been proposed to improve sleep quality during hospitalization and have shown promising results.Reference DuBose and Hadi 11
No data are currently available on subjective sleep quality in the emergency department (ED). The main objective of this study was to assess the subjective quality of patient nighttime sleep in the ED and its associated factors. It was hypothesized that subjective sleep quality in the ED would be significantly lower, as compared with the previous week at home. Moreover, lower subjective quality would be associated with modifiable factors (noise, light, and pain).
METHODS
Study design and population
This prospective observational cohort study was conducted in the ED of a tertiary care hospital with an annual census of approximately 65,000 ED visits (mostly adults). This study received approval from our institutional ethics review board.
Participant selection
A convenience sample of patients aged 18 years and older who consulted the ED from July 2015 to October 2015 was recruited according to the following inclusion criteria: 1) were on a stretcher; 2) slept at least one night in the ED; and 3) spoke French or English. Patients who were in the waiting or reanimation area during the night were excluded. Patients were recruited on weekday mornings (8:00 a.m. to noon) but had to arrive at the ED before 18:00 on the evaluated night.
Measurements
In the morning, after a night of sleep in the ED, participants were asked to complete a short sleep quality questionnaire adapted to the ED environment.Reference Freedman, Kotzer and Schwab 12 It contained six questions on the participant’s perceived quality of sleep in the ED and nine questions on certain factors that could have affected that sleep. Participants rated most questions on an 11-point numerical scale, ranging from 0 to 10, for example, “How would you rate the quality of your sleep last night?” for which zero indicated very poor and 10 indicated excellent sleep quality.
RESULTS
A total of 235 patients agreed to participate in the study. Their mean age was 64±20 years, and 51% were women. Subjective sleep quality in the ED was significantly lower than for the previous night at home (difference 1.4, 95% confidence interval [CI] 0.89–1.86, p<0.001), indicating a 20% decrease in the numerical scale of sleep quality. On average, participants rated their sleep quality at 5.4 (±3.2), as compared with a score of 6.8 for the previous week at home. Almost one-half the participants took more than 30 minutes to fall asleep, and participants reported waking up 3.5 times per night on average. Noise and stress had the highest mean scores among the proposed sleep disruption variables (Table 1). Using a stepwise multiple regression, stress (11%), noise (6%), pain (4%), and stretcher comfort (3%) were negatively associated with subjective sleep quality, whereas past week home sleep quality (1%) was positively related. These five factors together explained 25% of the variance in subjective sleep quality.
Table 1. Sleep variables and factors that affected sleep
ED=emergency department; SD=standard deviation.
DISCUSSION
This study is the first to assess sleep quality in an ED and showed that sleep quality was not optimal. Participants perceived 20% lower sleep quality in the ED, as compared with at home. Moreover, stress, noise, pain, and stretcher discomfort were perceived to affect sleep quality negatively.
The mean subjective sleep quality obtained in ICU studies (4.7±2.3 on a 10-point numerical scale)Reference Freedman, Kotzer and Schwab 12 was similar to that obtained in this study (5.4±3.2 on an 11-point numerical scale), suggesting that ED and ICU subjective sleep quality are comparable. The mean ED sleep quality in the present study was lower than the one found in a study of hospitalized patients using a similar sleep quality questionnaire (5.4 vs. 6.7, respectively, on an 11-point numerical scale).Reference Bano, Chiaromanni and Corrias 13 The mean number of awakenings per night for our patients was also higher (3.5±3.8 vs. 2.2±2.4, respectively), suggesting poorer ED sleep quality, as compared with a hospitalized setting. ED patients have less privacy and undergo more tests in a short timeframe, as compared with hospitalized patients. This could explain the similar quality of ED and ICU sleep.
The factors affecting sleep quality found in the present study, including noise, pain, and stretcher comfort, have been reported in previous ICU and hospital unit studies.Reference Pulak and Jensen 3 - Reference Yilmaz, Sayin and Gurler 10 , Reference Freedman, Kotzer and Schwab 12 , Reference Bano, Chiaromanni and Corrias 13 Stress during the night was the strongest predictor of lower subjective sleep quality. AnxietyReference Manian and Manian 8 and worries about the illnessReference Lei, Qiongjing and Qiuli 7 were previously shown to affect sleep quality significantly. In the ED, patients may not be fully diagnosed or not yet reassured by definitive treatment. Accordingly, effective pain treatment combined with adequate reassurance and a more sleep-friendly environment (low noise, low light, and fewer optional staff interventions) would improve the ED sleep experience. However, other unassessed factors in the present study may probably affect the patient’s subjective sleep quality, as only 25% of the total variance in the multiple regression analysis was explained.
LIMITATIONS
The sleep questionnaire used in this study has not been previously validated in an ED population. The use of a non-random convenience sample (recruited on weekdays), sampling bias resulting from participation refusal, and recruitment from only one ED reduces the generalizability of the results.
CONCLUSION
Subjective sleep quality is less than optimal in the ED and negatively influenced by stress, noise, pain, and stretcher comfort. Optimizing certain sleep disruption variables could improve sleep quality in the ED.
Acknowledgements
The authors would like to thank Dominique Petit and Margaret McKyes for their contributions to the manuscript revision.
Competing interests
None declared.
SUPPLEMENTARY MATERIAL
To view supplementary material for this article, please visit https://doi.org/10.1017/cem.2018.394
