Near-infrared spectroscopy in lower extremity trauma

Area of Science:

• Biomedical Engineering
• Physiology
• Trauma Research

Background:

• Near-infrared spectroscopy (NIRS) non-invasively measures tissue oxygen saturation up to 3 cm depth.
• NIRS assesses microcirculation hemoglobin oxygen saturation.
• Understanding tissue oxygenation post-trauma is crucial for clinical management.

Purpose of the Study:

• To quantify the immediate changes in leg tissue oxygenation after acute tibial fractures using NIRS.
• To establish a baseline of normal tissue oxygenation in uninjured legs for comparison.
• To evaluate the contralateral limb as an internal control for trauma response.

Main Methods:

• Twenty-six patients with acute unilateral tibial fractures and 25 healthy controls were enrolled.
• NIRS measurements were taken in four leg compartments (anterior, lateral, deep posterior, superficial posterior) bilaterally.
• Injured legs were compared to uninjured control legs and the patient's contralateral limb.

Main Results:

• Injured leg compartments showed mean oxygenation: 69% (anterior), 70% (lateral), 74% (deep posterior), 70% (superficial posterior).
• Uninjured control legs averaged: 54% (anterior), 55% (lateral), 60% (deep posterior), 57% (superficial posterior).
• NIRS values were significantly higher in injured legs by 15.4 percentage points (p < 0.0001) compared to uninjured legs, with contralateral limb control.

Conclusions:

• Acute tibial fractures predictably elevate tissue oxygenation, as detected by NIRS.
• The contralateral limb is a valuable internal control for assessing hyperemic responses to leg trauma.
• NIRS provides a reliable method for monitoring tissue oxygenation changes following acute injury.