A prospective randomized controlled study design was used to collect data. Patients undergoing MIE-McKeown in the Department of cardiothoracic surgery of Fuling Hospital of Chongqing University from March 2022 to June 2023 were prospectively collected as research objects. They were divided into three groups by random number table method: Group A: continuous RISS plane block+patient controlled intravenous analgesia (PCIA), Group B: single RISS plane block+PCIA, and Group C: control group, simple PCIA. The outcome indicators of each group were recorded and compared: ①Analgesic effect [visual analogue scale (VAS) pain score for rest and cough at 2, 6, 12, 24, and 48 hours after surgery], ②Postoperative use of analgesics [the amount of sufentanil used within 24 hours after surgery, the number of effective presses of the analgesia pump and the number of additional rescue analgesia], ③Adverse reactions during postoperative analgesia [dizziness, lethargy, postoperative nausea and vomiting(PONV), hypotension, respiratory depression, urinary retention, etc.], ④Intraoperative hemodynamic indicators [mean arterial pressure (MAP) and heart rate (HR) at different time points], ⑤Analgesia satisfaction. ①②③ were the primary outcome indicators, and ④⑤were the secondary outcome indicators.

A total of 96 patients who met the inclusion and exclusion criteria were enrolled, with 32 cases in each group. Group A patients had lower resting and cough VAS scores at 2, 6, 12, 24, and 48 hours after surgery compared to Group C. Group A had lower resting VAS scores at 2, 24 hours after surgery and lower cough VAS scores at 12, 24 hours after surgery compared to Group B. Group B patients had significantly lower resting VAS scores at 2, 6, 12 hours after surgery and lower cough VAS scores at 2, 6, 12, 24, and 48 hours after surgery compared to Group C (all P < 0.05). The dosage of sufentanil, the number of effective compressions of the analgesic pump, and the additional number of remedial analgesia gradually increased between groups A, B, and C within 24 hours after surgery, with statistical differences (all P < 0.01). The incidence of dizziness and PONV in Group C was higher than that in Groups A and B, respectively (both P < 0.05). There were no statistically significant differences in MAP and HR among the three groups of patients before anesthesia induction (T₀), immediately after skin incision (T₁), 5 minutes after skin incision (T₂), and 5 minutes after extubation (T₃) (all P > 0.05). The satisfaction with pain relief in Group A, Group B, and Group C decreased sequentially(P < 0.05).

Ultrasound guided RISS block can provide good postoperative analgesia for MIE-McKeown surgery. As an active exploration of multimodal analgesia, continuous RISS has better analgesic effects. It is safe, effective, and worthy of further clinical promotion and use.