Overview

This prospective, randomized, controlled trial aimed to evaluate whether fluid resuscitation guided by the Peripheral Perfusion Index (PPI) could reduce the incidence of Acute Skin Failure (ASF) in elderly critically ill patients. A total of 216 patients aged ≥65 years with sepsis or other types of shock requiring early aggressive fluid resuscitation were enrolled and randomly assigned in a 1:1 ratio to either the PPI-guided resuscitation group or the conventional resuscitation group. The intervention group targeted maintaining PPI ≥1.4 in addition to conventional hemodynamic goals, while the control group followed standard resuscitation protocols. The primary outcome was the incidence of ASF within 7 days of ICU admission, diagnosed according to NPUAP/EPUAP (2014) criteria. Secondary outcomes included time to ASF occurrence, lactate clearance, cumulative fluid balance, organ function, and long-term prognosis.

Eligibility

Inclusion Criteria:

1. Age ≥ 65 years.
2. Diagnosis of sepsis (according to Sepsis-3 criteria) or other types of shock requiring early and aggressive fluid resuscitation.
3. APACHE II score ≥ 15 at ICU admission.
4. Expected ICU length of stay ≥ 72 hours.
5. Written informed consent obtained from the patient or their legally authorized representative.

Exclusion Criteria:

1. Pre-existing stage III or higher pressure injury or skin necrosis at the time of enrollment.
2. Severe dermatological disease or peripheral vascular disease that could interfere with the assessment of skin or peripheral perfusion.
3. Inability to perform continuous finger pulse oximetry monitoring (e.g., due to bilateral finger injury, amputation, or severe peripheral edema).
4. Contraindications to liberal fluid resuscitation (e.g., acute cardiogenic pulmonary edema, severe heart failure with fluid overload).
5. Expected survival \< 24 hours due to terminal illness or irreversible condition. Concurrent participation in another interventional clinical trial.