Observation Of Using Different Doses Of Fentanyl Plus Bupivacaine In Spinal Anesthesia For Total Knee Arthroplasty In Elderly Patients

Objective To compare the effect of isobaric spinal anesthesia with bupivacaine and different dosage of fentanyl in elderly patients undergoing total knee arthroplasty, to explore the appropriate dosage of fentanyl with bupivacaine spinal anesthesia and provide a reference for the total knee arthroplasty in elderly patients.Methods 73 cases of elective knee replacement surgery in elderly patients, under bupivacaine-fentanyl isobaric spinal anesthesia, divided into three groups, Group B: bupivacaine 15 mg plus cerebrospinal fluid--3ml; group BF1: bupivacaine 15 mg plus fentanyl 25 ug plus cerebrospinal fluid-- 3ml, group BF2: bupivacaine 15 mg plus fentanyl 50ug-- 3ml; The heart rate(HR), blood pressure(BP), oxygen saturation(Sp02%) were monitored and recorded before anesthesia and 5min, l0 min, 15 min, 30 min, 1h after anesthesia,and the time of prosthesis implantation, and after surgery. Record the time of onset anesthesia, the highest plane of analgesia, sensory block duration, degree of motion block, the effect of intraoperative analgesia. Record the degree of pain and the dosage of analgesics used two days after surgery; Recorded intraoperative nausea, vomiting, pruritus, respiratory depression, and the use of vasoactive drug phenylephrine, urapidil, nitroglycerin, atropine in three groups.Results(1) General information: the aged, weight, height, ASA classification, gender of three groups had no significant difference(P> 0.05)(2) The operative time, urine, transfusion volume, blood loss of the three groups had no significant difference,(P> 0.05)(3) Hemodynamic changes: Compared with before anesthesia,the blood pressure of 5min、10min after anesthesia and prosthesis immediately had significant difference(P <0.05) in three groups;(4) The anesthetic effect: Compared with group B, the sensory and motor block dissipated time in group BF2 and group BF1 had significant difference(P <0.05), group BF2 compared with group BF1 was also significant difference(P <0.05);(5) NRS score: Compared with group B, after 12 hours of surgery, the NRS score in group BF1, group BF2 had significant difference(P <0.05);(6) There was no significant difference of adverse reactions in three groups(P> 0.05).