Noise in the Intensive Care Unit
Condition: Noise in the ICU; Sleep Quality in Adult ICU Patients
Study type: Observational

Summary: 
      Rationale: Sound levels in the Intensive Care Unit are frequently reported to exceed the
      recommended levels. It is plausible to assume that this causes sleep disturbance in the
      patients on the ICU.

      Goals/endpoints: to assess sound pressure levels in 6 different Dutch ICU´s and evaluate the
      effect of higher levels on sleep as perceived by the patient.

      Study design: observational multicenter study

      Study population: adult ICU patients > 18 years old with an expected duration of stay of more
      than 24 hours

      Study parameters/endpoints:

      Primary

        1. To gather information on how Dutch ICUs perform on sound levels

             1. Average sound pressure level

             2. Number of sound peaks

        2. To question patients about their perception of sleep quality (measured by RCSQ)

        3. Causes of elevated sound pressure levels

        4. Identification of the most annoying sounds experienced by the patient

      Secondary

      1) Incidence of delirium measured by CAM-ICU
    

Detailed description: 
      An exploratory prospective-observational multi-center study with a total of 6 participating
      hospitals will be performed. We will include 15 patients per center. Characteristics of the
      participating ICUs will be collected.All adult patients without hearing disabilities and
      admitted to the ICU more than 48 hours ago, with a Richmond Agitation-Sedation Scale (RASS)
      of -2 or higher and the capability to understand Dutch are eligible.Sound measurement
      equipment will be installed in two patient rooms in each ICU and will perform a continuous
      recording. Sound parameters that will be measured include average sound levels, number and
      height of peaks and peak-to-baseline level.

      Level of sedation is monitored as part of daily care by nurses in all patients every two
      hours using the RASS.In addition, screening on the presence of delirium is done using the
      Confusion Assessment Method-ICU (CAM-ICU) every shift.Patients' perception of sleep will be
      scored (both by the patient and the attending nurse) using the Richards-Campbell Sleep
      Questionnaire (RCSQ),after the 24 hour recording period from the start of the inclusion and
      from there on every 24 hours until discharge with a maximum of five days at 07.00 am by the
      attending nurse.

      Data, consisting of patient information and results of measurements and laboratory
      investigations will be filled in on an electronic Case Record Form (e-CRF).

      For the descriptive statistics, values will be given as mean ± SD or median and interquartile
      ranges, depending on their distribution. Summary tables will be provided for all baseline and
      follow-up variables. Data will be summarised by producing frequently tabulations for
      categorical variables and summary statistics for continuously distributed variables with
      confidence intervals.

      All statistical tests are two-sided and statistical significance is defined as a P-value
      <0.05. All data are analyzed using SPSS version 18.0 (SPSS, Chicago, IL).

      Association between noise and delirium will be evaluated using a logistic multivariate
      regression analysis, correcting for age, severity of disease, infection and sedative use
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        All adult patients without hearing disabilities and admitted to the ICU more than 48 hours
        ago, with a Richmond Agitation-Sedation Scale (RASS) of -2 or higher and the capability to
        understand Dutch are eligible.
      
Keywords: sleep; noise; ICU; delirium; RCSQ