Nan Fang Yi Ke Da Xue Xue Bao · Apr 20, 2021

Effects of dexmedetomidine doses on postoperative cognitive dysfunction and serum β- amyloid and cytokine levels in elderly patients after spine surgery: a randomized controlled trial

By Li Z, Li H, Yao S et al.

OBJECTIVE: To explore the immunomodulatory mechanism and optimal dose of dexmedetomidine (DEX) for preventing postoperative cognitive dysfunction (POCD) in elderly patients undergoing spinal surgery. OBJECTIVE: A total of 120 elderly patients undergoing elective spinal surgery with general anesthesia were randomized into 4 groups to receive a loading dose of 0.3 μg/kg DEX for 10 min before anesthesia induction followed by maintenance doses of 0.2, 0.5, and 0.8 μg · kg⁻¹·h⁻¹ (low-, medium-, and high-dose DEX groups, respectively) or an equal volume of normal saline (control group). DEX and saline was discontinued 40 min before the end of the surgery. Before induction (D₀) and on day 1 (D₁), day 3 (D₂) and day 7 (D₃) after the operation, the cognitive function of the patients was assessed using the MMSE scale and their serum levels of β-amyloid (Aβ), TNF-α, IL-1β and IL-6 were measured. The occurrence of adverse effects including bradycardia and hypotension and the recovery time of the patients were recorded. OBJECTIVE: Compared with those on D₀, serum levels of Aβ, IL-1β, IL-6, and TNF-α on D₁ were markedly increased in all the groups (P < 0.05); the levels of Aβ decreased to the baseline level on D₃ in medium- and high-dose DEX groups (P > 0.05) but remained high in the other two groups. On D₂, TNF-α, L-1β and IL-6 recovered their baseline levels in medium- and high-dose DEX groups (P > 0.05) but remained elevated in the other two groups. The incidences of POCD in medium- and high-dose DEX groups were comparable but significantly lower than that in the control group (P < 0.05). The incidences of hypotension and bradycardia were the highest in high-dose DEX group (P < 0.01), which also had longer recovery time than the other 3 groups (P < 0.05). OBJECTIVE: With a loading dose of 0.3 μg/kg followed by a maintenance doses of 0.5 μg · kg⁻¹·h⁻¹, DEX can effectively reduce the incidence of POCD in elderly patients undergoing spinal surgery by inhibiting the production of Aβ and pro-inflammatory cytokines.

doi.org/10.12122/j.issn.1673-4254.2021.04.18PubMed 33963722Interventions