The influence of analgesic-based sedation protocols on delirium and outcomes in critically ill patients: A randomized controlled trial

OBJECTIVE: To investigate the influence of analgesic-based midazolam sedation on delirium and outcomes in critically ill patients and to analyze the risk factors of delirium. DESIGN: Single center, prospective randomized controlled trial. SETTING: A surgical intensive care unit (ICU) in a tertiary care hospital in China. PATIENTS: Mechanically ventilated patients requiring sedation. MEASUREMENTS AND MAIN RESULTS: Patients admitted to the surgical intensive care unit who required sedation and were undergoing mechanical ventilation for longer than 24 hours were randomly divided into three groups: 1) the remifentanil group received remifentanil and midazolam, 2) the fentanyl group received fentanyl and midazolam, and 3) the control group received only midazolam. The analgesic effect, sedation depth, and presence of delirium were evaluated. To compare the effect of different therapies on the occurrence of delirium, days of mechanical ventilation, length of the ICU stay, and 28-day mortality were measured along with the risk factors for delirium. A total of 105 patients were enrolled, and 35 patients were included in each group. Compared to the control group, patients who received remifentanil and fentanyl required less midazolam each day (P = 0.038 and <0.001, respectively). Remifentanil has a significant effect on reducing the occurrence of delirium (P = 0.007). The logistic regression analysis of delirium demonstrated that remifentanil (OR 0.230, 95%Cl 0.074–0.711, P = 0.011) is independent protective factors for delirium, and high APACHE II score (OR 1.103, 95%Cl 1.007–1.208, P = 0.036) is the independent risk factor for delirium. CONCLUSION: Remifentanil and fentanyl can reduce the amount of midazolam required, and remifentanil could further reduce the occurrence of delirium.