The Effect Of Dexmedetomidine On Analgesia And Early Postoperative Cognitive Function In Elderly Patients With Orthopedic Surgery

ObjectiveThis study sought to evaluate intraoperative and postoperative sustained application of dexmedetomidineon senile knee joint replacement in patients with postoperative early cognitive function, analgesia and inflammatory effect.MethordsWe randomly assigned 86 cases of elderly patients undergoing unilateral total knee arthroplasty, aged 65-79, and divided into two groups.Dexmedetomidinegroup(Dex group) intraoperative and postoperative PCIA continuous intravenous infusion of dexmedetomidine, control group(Con group) intravenous infusion of amount of saline.Nerve block compound by intravenous anesthesia were employed to groups enrolled. Record the patient each time point of vital signs, the amount of intraoperative and postoperative, the dosage of propofol, etc.Employ postoperative application of neuropsychological test to record and table preoperative and postoperative cognitive function determination and detection of patients before and 1 d, postoperative 1,3,5 d serum glutamic acid amino transfer enzyme (ALT), alanine aminotransferase (AST), creatinine (CRE), blood urea nitrogen (BUN), C reactive protein (CRP) and leukocyte mediated IL 6 (1L-6) level; after 4h,24h,48h,72h and postoperative 5d passive flexion and extension joint or activities of pain on a visual analogue scale (VAS) scores and sedation score (Ramsay score).ResultsThere is no significant difference between the two groups of patients with operation time and awake time but in the DEX group propofol dosage was significantly less than that of the con group (P< 0.05).5 d after operation in patients with onset of cognitive impairment (POCD) rate of DEX group was significantly lower than that in con group (P< 0.05).Con group with 1 case occurred in intraoperative awareness. Two groups of patients ALT, AST, BUNwere in normal range. The serum Cre at 3,5 d after operation Dex group was significantly lower than the Con (P< 0.05). The VAS grade ofDex group is less than the Con group at t2, t3 and t4 (P< 0.05),but the Ramsay grade of Dex group is more than the Con group at t0 and t1 (P< 0.05).Compared to the day before operation, CRP in the two groups were significantly higher at 1,3,5d after operation respectively. Also 5d after operation Dex group was lower than that in group Con (P< 0.05). Compared to the day before operation, IL-6 only at 1,3d after operation was higher significantly (P< 0.05),but at 5d after operation it ws not. And Dex group was lower than that in group Con at 3,5d after operation (P< 0.05)Conclusion Perioperative continuous application dexmedetomidine which can improve early postoperative cognitivefunction and reduce the incidence of POCD, also had no adverse effect on elderly patients with hepatic and renal function. At the same time it can reduce postoperative pain and inflammatory respose to a certain extent,and improve the patient's postoperative rehabilitation which has an important clinical significance.