Analysis of the effect of dexmedetomidine combination with regional anesthesia on the cognitive state in the post-anesthesia period in ophthalmic surgery
Authors: Dorofeeva G.S. 
Published: October 2021

Given a reduced cognitive reserve in patients in ophthalmic surgery, an anesthesiologist should pay special attention when choosing a method of anesthesia to prevent the development of postoperative cognitive dysfunction. The concept of multimodal anesthesia makes it possible to reduce the total number of narcotic analgesics and ataractics used intraoperatively while maintaining an adequate level of anesthesia and sedation, both intraoperatively and in the postoperative period. In ophthalmic surgery, regional anesthesia (pterygopalatine fossa blockade) is used before surgery in combination with infusion of dexmedetomidine. Materials and methods. The study was conducted at the premises of Dnipropetrovsk Regional Clinical Ophthalmologic Hospital, 61 patients were examined after penetrating keratoplasty. The age of the subjects ranged from 18 to 60 years (mean age of 52.1 ± 2.0 years). Patients were randomized into two groups. Group d (n = 30) are patients who received anesthesia according to the following scheme: premedication for 40 min — infusion of dexmedetomidine, ondansetron 4 mg, dexamethasone 4 mg, ketorolac 30 mg intravenously; induction — propofol 2–2.5 mg/kg fractionally until the onset of the clinical signs of anesthesia, fentanyl 0.005% 0.1 mg; relaxation on the background of atracurium besylate 0.3–0.6 mg/kg, tracheal intubation; maintenance of anesthesia: oxygen — sevoflurane mixture with FiO2 50–55 %, end-expired sevoflurane 1.4–1.8 vol.% (1–1.5 minimum alveolar concentration), use of low-flow technique. In the second group (db, n = 31), anesthesia was performed as in group d with the addition of pterygopalatine fossa blockade. Group d included 18 (60 %) men and 12 (40 %) women, mean age of 49.5 ± 2.5 years; db group — 16 (51.61 %) men and 15 (48.39 %) women (p = 0.583 according to the chi-square), mean age of 55.5 ± 3.2 years (p = 0.142 according to the t-test). Results. A comparative analysis of changes in cognitive status between db and d groups has shown no significant changes (p < 0.05) at different stages of neuropsychological testing. When considering the results of testing to assess short-term verbal memory in db and d groups, there was a 25 % decrease in the first 6 hours after surgery. After all, in d group, the indicators remained low compared to baseline until the 7th day of the postoperative period, while in the db group the recovery of short-term memory occurred one day after surgery. In both groups, the result of the Luria test on day 21 exceeded the baseline by 12.5 % in both groups. Examination using visual analogue scale has demonstrated that patients in db group felt better than those in d group. Conclusions. Thus, we see that the combination of dexmedetomidine with regional anesthesia in addition to less impact on the cognitive state improves the subjective well-being in the postoperative period in patients in ophthalmic surgery. Due to this, another link of influence on the etiological factors of postoperative cognitive dysfunction formation seems to appear.