The effect of intravenous remifentanil and fentanyl postoperative delirium incidence in patients receiving elective orthopedic surgeries

Background: The use of certain opioids associated differently with the incidence of postoperative delirium (POD). Remifentanil and fentanyl are short-acting opioids widely used in surgery; however, studies assessing their relationship with POD incidence are still limited. This study aimed to determine the association of remifentanil and fentanyl uses with the incidence of POD in elective orthopedic surgery patients. Methods: A cross-sectional study was conducted in Surgical Unit at Dr Soetomo General Academic Hospital in Surabaya, Indonesia from August to September 2022. Patients who underwent elective orthopedic surgery and used remifentanil (n=16) and fentanyl (n=14) as postoperative analgesia were enrolled in the study. Delirium was assessed using Confusion Assessment Method-ICU tool (CAM-ICU). The associations of remifentanil and fentanyl use as well as patients’ characteristics with POD incidence were assessed statistically. Results: Our data found that there was no significant difference between the incidence of POD with the use of remifentanil (p=0.125) in orthopedic surgery patients. The total doses of fentanyl and morphine equivalent (of remifentanil or fentanyl) were associated significantly with the POD incidence (p=0.010 and p=0.002, respectively). Other factors associated with POD incidence were the use of bone cement during the surgery (p=0.034), duration of surgery (p<0.001), and bleeding volume during the surgery (p=0.024). Conclusions: Our study showed high dose of fentanyl, use of bone cement, longer duration of surgery, and high bleeding volume have greater risk of developing POD in orthopedic surgery patients.