To evaluate the efficacy and safety of a topical palmitoleic acid (POA) oil composition in preventing PIs and reversing Stage I damage using an integrated physiological monitoring approach.

A prospective, single-center, self-controlled study was conducted enrolling adult inpatients at high risk for PIs (SEM >0.5) or with existing Stage I PIs from Ruijin Hospital, Shanghai Jiao Tong University School of Medicine . Participants received standard preventive care plus topical POA oil composition (1 mL to sacral area, 4 times daily for 14 days). Primary outcomes included changes in SEM and TcPO₂. Assessments were performed at baseline, day 7, and day 14.

Inclusion Criteria:

• Adult inpatients (aged above 18 years).
• High risk for sacral pressure injuries, objectively defined by an abnormal hydration status (Sacral Subepidermal Moisture [SEM] Delta > 0.5) at screening.

Exclusion Criteria:

• Medical contraindications to standard repositioning protocols (e.g., unstable pelvic fractures).
• Use of topical medications or advanced prophylactic dressings on the sacrum within 14 days prior to enrollment.
• Active peripheral vascular disease significantly impairing local tissue perfusion.
• Documented hypersensitivity to the investigational product (POA) or its vehicle components.

The datasets generated or analysed during the current study are not publicly available due to restrictions by the ethics to protect participant privacy. Data may be available from the corresponding author upon reasonable request and with appropriate approvals.