Environmental interventions, such as reducing noise, playing white noise such as ocean sounds, and decreasing
interruptions to sleep for care, also are safe and logical interventions that ICU nurses should use to help patients sleep. Progressive muscle relaxation has been extensively studied and shown to be efficacious for improving sleep in persons with insomnia; however, progressive muscle relaxation requires that patients consciously attend to relaxing specific muscle groups and practice these techniques, which may be difficult for critically 11 patients.