Standard Nursing Care

MDC-based Pain Management

The control group received standard perioperative nursing care in accordance with the Chinese Consensus and Clinical Guidelines for Enhanced Recovery After Surgery (2021 edition) and the Expert Consensus on Perioperative Nursing of Anorectal Diseases (2022 edition). Preoperative fasting included a 6-hour restriction on solid food and a 2-hour restriction on clear liquids. At 8:00 p.m. on the night before surgery, patients were instructed to orally ingest 500 mL of 10% glucose solution to supplement energy reserves. Fifteen minutes of structured health education was delivered preoperatively by the assigned nurse using 3D animations to explain the surgical process. Intraoperatively, an inflatable warming blanket was used to maintain the core temperature at 38°C, and all infusion fluids were pre-warmed to 37°C. For infection prophylaxis, 30 minutes before incision, patients received intravenous cefazolin (1 g for body mass index [BMI] < 25 kg/m²; 2 g for BMI ≥ 25 kg/m²).

The SF-MPQ includes two core components: the pain rating index (PRI) and present pain intensity (PPI). The PRI assesses the qualitative aspects of pain using 11 sensory descriptors (e.g., stabbing, throbbing) and 4 affective descriptors (e.g., fearful, exhausting), with a total score ranging from 0 to 45. The PPI is a single-item, 6-point scale (0 = no pain, 5 = excruciating pain).

The VAS [27] was used to assess pain intensity at five postoperative time points: immediately after surgery (T0), and at 4 hours (T1), 12 hours (T2), 24 hours (T3), and 48 hours (T4) postoperatively. The VAS consists of a 10 cm horizontal line anchored by "no pain" at 0 cm and "worst possible pain" at 10 cm; patients were asked to mark the point that best reflected their current pain level. The mark was then converted into a numeric score ranging from 0 to 10. Pain intensity was categorized as follows: 1-3 (mild, does not interfere with daily activities), 4-6 (moderate, interferes with sleep), and 7-10 (severe, completely disabling). The scale demonstrated strong internal consistency (ICC = 0.89, P < 0.001) and high concurrent validity with the Numerical Rating Scale (r = 0.94)

Four objective time-based recovery parameters were recorded: (1) Time to first defecation, defined as the number of hours from anesthesia recovery to the first spontaneous bowel movement; (2) Time to first ambulation, defined as the time postoperatively at which the patient could independently stand and walk for ≥5 minutes; (3) Wound healing time, defined as the number of days required for complete epithelialization and absence of exudate, as confirmed by blinded assessment by the attending physician; (4) Length of postoperative hospital stay, measured in calendar days from the end of surgery to the date of discharge documentation.

Postoperative complications within 30 days were identified and recorded based on internationally accepted diagnostic criteria: (1) Urinary retention, defined as a bladder volume >400 mL on ultrasound requiring catheterization (per the International Continence Society standard); (2) Perianal edema, defined as a palpable perianal bulge ≥1 cm in diameter with tenderness, confirmed via blinded physician assessment; (3) Wound infection, meeting criteria established by the Centers for Disease Control and Prevention (erythema, swelling, warmth, pain, and purulent discharge or white blood cell count >10×10⁹/L); (4) Constipation, defined as no defecation within 72 hours postoperatively requiring pharmacological intervention (Rome IV criteria); (5) Anal distension, characterized by persistent anal pressure or fullness with a VAS score ≥4 sustained for more than 24 hours.