Trial to Evaluate the Effects of Sound Modulation on Critically Ill Patients (SMART)

Brian Gehlbach

Status: Completed

Conditions: Delirium; Physiological Stress; Critical Illness; Sleep Deprivation

Treatments: Device: Sound masking; Device: Sound reduction

Study type: Interventional

Funder types: Other

Identifiers

NCT03019133

201609843

Details and patient eligibility

About

The goal of the project is to determine the effects of noise masking and noise reduction on stress related physiological parameters in critically ill patients admitted to the intensive care unit.

Full description

Sleep deprivation is common in critically ill patients in the intensive care unit (ICU) and may impair recovery. While noise is widely cited as the most common cause of sleep disruption in the ICU setting, its contribution to sympathetic activity in critically ill patients is not known. This is an important knowledge gap, because noise initiates a sequence of physiological changes including vasoconstriction, raised diastolic blood pressure, pupil dilatation and muscle tension. Furthermore, noise is implicated in sympathetic arousals, resulting in a release of adrenaline which prevents relaxation and consequently prevents the patient from falling asleep.

The investigators plan to study the effect of noise masking and noise reduction on stress related physiological parameters in critically ill patients admitted to the ICU. Subjects will be randomized into 3 separate groups: control, noise reduction, and noise masking. The investigators will compare the heart rate and blood pressure variability between and within the groups to determine the effects of treatment assignment on these variables. Non-invasive measurements obtained from the bedside monitor will be collected using physiological data acquisition software.

Enrollment: 120 estimated patients

Sex: All

Ages: 18 to 99 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Subjects aged 18-99 years who are expected to receive care on an adult critical care unit for at least 24 hours

Exclusion criteria

• Admission for drug overdose or with a known substance abuse disorder
• Untreated sleep apnea disorder, narcolepsy, REM sleep behavior disorder, parasomnia, restless leg syndrome or other sleep disorder
• Use of hearing aids, or known significant conductive or sensory hearing loss
• Ventilator support via an endotracheal tube
• Use of vasopressors
• Unresponsive or delirious
• Subjects with known Dementia, Parkinson's disease, or other neurodegenerative disorder
• Subjects with a pacemaker or who have received cardiac transplant

Trial design

Primary purpose: Supportive Care

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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120 participants in 3 patient groups

Usual Care

No Intervention group

Description:

Usual care will be provided.

Sound reduction

Active Comparator group

Description:

Use of noise reduction headphones. Pro For Sho safety ear muffs with a noise reduction rate of 34dB will be used.

Treatment:

Device: Sound reduction

Sound masking

Active Comparator group

Description:

Use of headphones and relaxing music. Sennheiser HD 280 pro headphones will be used for sound masking.

Treatment:

Device: Sound masking