Analgesic Effect of Intraoperative Intravenous S-Ketamine During Total Knee Arthroplasty Surgery

Analgesic Effect of Intraoperative Intravenous S-Ketamine During Total Knee Arthroplasty Surgery:A Randomized Controlled Clinical Trial

Severe acute pain after total knee arthroplasty surgery has multiple implications for hospitals and patients, monopolising resources and affecting the quality of life. S-ketamine inhibits N-methyl-d-aspartate (NMDA) receptor activation and attenuates central sensitization associated with hyperalgesia, opioid tolerance.Therefore, the primary aim of this trial was to investigate whether s-ketamine decreases pain and opioid consumption postoperatively in adult individuals undergoing total knee arthroplasty surgery.

Total knee arthroplasty surgery is considered a cost-effective therapy for end-stage knee osteoarthritis (KOA). With an ageing population and rising rates of obesity in the world, knee joint replacements are estimated to escalate. While joint replacement is a cost effective intervention,approximately 20% of people experience persist pain postoperatively. The surgical injury triggers a myriad of responses in the pain matrix, from sensitization of peripheral and central pain pathways to feelings of fear, anxiety and frustration.

Opioids are effective for acute postoperative pain but have numerous adverse effects. In addition, postoperative opioid treatment may pose a risk of opioid addiction.

Numerous publications state that adjuvant s-ketamine reduces pain and opioid consumption postoperatively . Whether intraoperative intravenous s-ketamine alleviates postoperative acute pain after total knee arthroplasty surgery still unclear . Therefore, a randomized, controlled, clinical study was designed to observed analgesic effect intraoperative intravenous a lower doses of s-ketamine(0.3mg/kg/h) with patients after total knee arthroplasty surgery .

Inclusion Criteria:

1. ASA physical statusI-III;
2. Patients understood the study in detail and voluntarily signed the informed consent before the study;
3. Patients to be treated with total knee arthroplasty Surgery under General anesthesia;
4. Elderly patients(≥65y),regardless of gender;
5. Patients can communicate normally;
6. Patients who have no contraindications to drugs such as midazolam,fentanyl,s-ketamine.

7.18 kg/m2 ≤BMI≤30 kg/m2;

Exclusion Criteria:

1. Increased intracranial or intraocular pressure;
2. severe hypertension;
3. unwillingness the study;
4. severe psychiatric disease and mental system diseases;
5. severe respiratory diseases;
6. hyperthyroidism;
7. liver and kidney dysfunction;
8. alcohol or drug abuse;
9. allergy to midazolam,fentanyl,s-ketamine.