Development and preclinical study of nursing dressing for Ⅰ/shallow Ⅱ degree burn wounds based on sodium hyaluronate carbomer composite hydrogel

Complete neo-epithelisation is defined as 100% coverage of the grafted burn wound area by new epithelial tissue without any residual open wound, as determined by two independent blinded assessors using standardized clinical photography combined with digital planimetry software (ImageJ or equivalent). Wound images will be captured at baseline (Day 0) and at each follow-up visit (Days 7, 14, 21, 28, 35, 42, 50) using a standardized photography protocol (fixed camera distance, lighting, and anatomical reference markers). The percentage of wound area achieving complete neo-epithelisation will be calculated as: (area of neo-epithelialized tissue / total initial wound area) × 100%. The primary endpoint is the proportion of participants achieving complete neo-epithelisation by Day 50.

Pruritus (itching) severity will be assessed using the Numerical Rating Scale (NRS), a validated self-reported scale where participants rate their worst itching intensity over the past 24 hours on an 11-point scale ranging from 0 (no itching) to 10 (worst imaginable itching). Participants will complete the NRS assessment daily from Day 0 (baseline, prior to dressing application) through Day 50. The primary metric for this outcome is the mean change from baseline in NRS score at Day 50. Secondary metrics include: (1) the proportion of participants achieving a clinically meaningful reduction in pruritus (defined as ≥ 4-point decrease from baseline or NRS score ≤ 3); (2) time to onset of pruritus relief (first day with ≥ 2-point decrease maintained for ≥ 3 consecutive days); and (3) area under the curve (AUC) of NRS scores over the 50-day study period. Higher scores indicate worse pruritus severity.