The effects of a sensory stimulation intervention for preventing delirium in a surgical intensive care unit: A randomized controlled trial

Background: Despite extensive efforts and advances in developing and fostering evidence-based delirium prevention interventions, the incidence of delirium remains high in hospitalized patients. Evidence suggests that sensory stimulation is a core component in interventions to prevent delirium among critically ill patients. However, its impact on the occurrence and outcomes of delirium is poorly understood. Objective: To evaluate the effects of a sensory stimulation intervention on preventing delirium in a surgical intensive care unit (ICU). Design: A prospective, assessor-blind, parallel-group randomized controlled trial. Settings and Participants: Adult patients were recruited from a surgical ICU of one tertiary hospital in Guangzhou, China. Methods: Participants in the intervention group received a daily 30-min auditory and visual stimulation session for a week, taking into consideration the participants' predefined condition and intervention protocol. The primary outcomes were delirium incidence and delirium-free days, and the secondary outcomes were delirium duration, severity and the first occurrence of delirium. Demographic and clinical data were collected at recruitment, and delirium was assessed three times a day for seven consecutive days using Confusion Assessment-ICU. Results: One hundred and fifty-two participants were randomly assigned to intervention or control groups. For primary outcomes, there were fewer patients with delirium in the intervention group than in the control group (10 vs. 19, risk ratio = 0.53), although statistical significance was not reached. The result showed that there were longer delirium-free days among participants in the intervention group than in the control group (3.66 vs. 2.84, p = .019). For secondary outcomes, the intervention could significantly reduce delirium duration (1.70 +/- 0.82 vs. 4.53 +/- 2.74 days, p = .004) and delirium severity (3.70 +/- 1.25 vs. 5.68 +/- 1.57, p = .002). The Kaplan-Meier curve showed the intervention group had a significantly delayed first occurrence of delirium compared with the control group (p = .043). Conclusions: The study did not provide significant evidence to support that sensory stimulation could reduce the incidence of delirium, but significant difference on delirium-free days.