Abstract: Objective To investigate the effects of dexmedetomidine (Dex) on somatosensory evoked potentials (SEPs) and transcranial electric motor evoked potentials (TCeMEPs) during idiopathic scoliosis orthopedic surgery. Methods A total of 60 patients, Cobb angle 60°‒100°, American Society Anesthesiologists (ASA) Ⅰ or Ⅱ, who underwent idiopathic scoliosis orthopedic surgery under general anesthesia were enrolled. According to the random number table method, they were divided into two groups (n=30): a Dex group (group D) and a control group (group C). Patients in group D were injected with Dex using a micro‑pump at a load‑dose of 1 μg·kg−1·h−1 at the beginning of anesthesia induction for 10 min, and then reduced to 0.4 μg·kg−1·h−1 till 2 h before the end of surgery, while the same volume of normal saline was given to patients in group C. Their mean arterial pressure (MAP), heart rate, pulse oxygen saturation (SpO2), recovery time, extubation time and Ramsay sedation score, and SEP and TCeMEP changes in amplitude and latency were recorded at the following time points: when entry into the operation room (T0), at the end of Dex loading dose (T1), when micro‑pump injection of Dex for 30 min (T2), 60 min (T3), 90 min (T4). Results There was no significant difference in age, operation time between the two groups (P>0.05). Compared with group C, patients in group D presented less blood loss, prolonged recovery time and extubation time, and increased Ramsay sedation score (P<0.05). There was no significant difference in MAP and heart rate between the two groups at T0 (P>0.05). Compared with group C, group D showed significant decreases in MAP and heart rate at T1, T2, T3 and T4 (P<0.05). There was no significant difference in SpO2 between the two groups at each time point (P>0.05). Compared with group C, no statistical difference was found in the amplitude and latency of SEPs and TCeMEPs in group D (P>0.05). Conclusions The use of Dex cannot affect SEPs and TCeMEPs during idiopathic scoliosis osteotomy, but can reduce the doses of general anesthetics and decrease MAP to reduce intraoperative bleeding and facilitate the whole process. It also decreases heart rate to maintain hemodynamics stable, while reducing agitation during the recovery period.
|