Discussion
delirium, cognitive behavior, psychiatric disorder, traumatic, stress disorder, pain, PTSD, trauma
EVENTS, EVENT, PATHOGENESIS
Posttraumatic stress disorder is arguably the most common psychiatric disorder to arise after exposure to a traumatic event. Although trauma-focused cognitive behavior therapy is the best-validated treatment for PTSD, it has stagnated during recent decades, and only two-thirds of patients with PTSD respond adequately to this intervention. Moreover, most people with PTSD do not access evidence-based treatment.In this randomized clinical trial, the patients with trauma who were sedated with dexmedetomidine were less likely to develop PTSD compared with those infused with normal saline. The trial found that the occurrence of PTSD in patients with trauma in the emergency department could be prevented by early anesthetic management. Our results showed that the CAPS-5 scores and the incidence of PTSD were significantly lower in the dexmedetomidine group compared with the control group 1 month after surgery, indicating that dexmedetomidine could reduce the severity and occurrence of PTSD in patients with trauma in the emergency department. However, the occurrence of PTSD is affected by a variety of factors.We performed a post hoc subanalysis of patients with the intervention because of a high nonadherence rate in the intervention group. In our study, dexmedetomidine dose was negatively correlated with the occurrence of PTSD in the dexmedetomidine group. Dose and time window effects of dexmedetomidine in preventing the occurrence of PTSD might exist in patients undergoing emergency trauma surgery. The study found no significant correlation between dexmedetomidine dose and the CAPS-5 scores in the dexmedetomidine group. No relationship was found between PTSD severity and dexmedetomidine dose. A ceiling effect of the total dose of dexmedetomidine might exist, or the sample size of this subgroup analysis was not enough to detect the difference. Further studies are needed to confirm the exact relationship between dexmedetomidine dose and PTSD.Hemodynamic changes are of concern in patients with trauma sedated with dexmedetomidine. Dexmedetomidine inhibits central sympathetic excitation because of its sedative effect, thereby reducing the patient’s heart rate and mean arterial blood pressure. However, dexmedetomidine can also activate peripheral αIn addition to dexmedetomidine, other anesthetics used during the surgery also had potential effects on PTSD. Previous studies found that propofol had an unusual reinforcing effect on conditioned fear memory and increased the risk of postoperative PTSD.The pathogenesis of PTSD is complex, and several potential mechanisms may underlie the preventive effects of dexmedetomidine on PTSD. The release of norepinephrine during or shortly after stressful and traumatic events can increase the formation of event-related fear memory, thereby inducing PTSD.Notably, dexmedetomidine had no effect on the incidence of postoperative delirium after 3 days and pain scores after 2 days post surgery. This finding might be closely related to the relatively young patients with trauma in this study, time and dose of dexmedetomidine used, sample capacity, and relatively well-developed postoperative analgesia. Sleep quality is closely related to PTSD.