Objective. To investigate the clinical application of preoperative adductor canal block combined with general anaesthesia in elderly patients with total knee arthroplasty. Methods. Seventy-four patients scheduled for elective TKA in Shaanxi Nuclear Industry Hospital No. 215 were selected and were assigned into group A (continuous ACB prior to the induction of anaesthesia) and group B (continuous ACB after extraction of the tracheal catheter post-operatively) according to the random number table method. Pre and postoperative plasma adrenaline and noradrenaline levels were measured; mean arterial pressure (MAP) and heart rate (HR) were recorded at the admission and the surgical skin incision; intraoperative sufentanil dosage, number of analgesic pump presses at 48 h postoperatively; postoperative adverse effects and length of stay were recorded; resting and active VAS pain scores were assessed at 4, 8, 12, 24, and 48 h postoperatively. Results. Group B experienced a substantial increase in MAP and HR at the time of surgical skin incision, while group A registered a smaller change and a stable haemodynamic profile (
P
<
0.05
). The plasma adrenaline and norepinephrine concentrations in group B were elevated compared to the preoperative period, differentially with group A. Group A received less intraoperative sufentanil than Group B (
P
<
0.05
). Conclusion. Collectively, postoperative resting VAS scores and active VAS scores remained lower in TKA patients who were subjected to preoperative and postoperative ACB, while preoperative ACB in conjunction with general anaesthesia decreased intraoperative sufentanil dosage, contained the surgical stress response, and maintained a stable intraoperative haemodynamic state, in what is probably a preferable option for elderly patients undergoing TKA. This study has served as a reference for postoperative patients to reduce their medication and for clinicians in the treatment going forward.