Continuous femoral nerve block and patient-controlled intravenous postoperative analgesia on Th1/Th2 in patients undergoing total knee arthroplasty

Abstract

The purpose of this study is to observe and compare the effects of continuous femoral nerve block (cFNB) and patient-controlled intravenous analgesia (PCIA) on postoperative analgesia and Th1/Th2 in patients undergoing total knee arthroplasty (TKA). Forty-six TKA were selected and randomly divided into two groups: the cFNB group and PCIA group. Patients in the two groups all underwent general anesthesia using a laryngeal mask. In the cFNB group, the femoral nerve block and catheterization were performed after induction of general anesthesia: 0.375% ropivacaine hydrochloride with a 20 mL loading dose was provided. After the end of the operation, the electronically controlled analgesia pump was connected. In the PCIA group, fentanyl with a 0.05 mg loading dose was provided and the electronic controlled analgesia pump was connected at the end of the operation. Venous blood was collected before anesthesia (T0), 1 h postoperatively (T1), 24 h postoperatively (T2) and 48 h postoperatively (T3). Th1/Th2 was calculated and analyzed by flow cytometry, and other indexes of these time points were recorded. The results show that there was no significant difference between the two groups regarding changes in blood pressure, heart rate and postoperative sedation Ramsay score. There was no significant difference in Th1 percentages (Th1%), Th2 percentages (Th2%) and ratios of Th1-to-Th2 (Th1/Th2) between the two groups at T0, T1 and T2 (P>0.05), while the Th1%, Th2% and Th1/Th2 of the PCIA group were lower than those of the cFNB group at T3 (P less than 0.05). It was concluded that cFNB represents a better postoperative analgesia for patients than PCIA, and has a lesser effect on Th1/Th2 balance, which can improve the outcome of patients.