Graduated, static, external compression of the lower limb: a physiological assessment

Area of Science:

• Vascular Physiology
• Medical Engineering

Background:

• Deep vein thrombosis (DVT) is a significant clinical concern.
• Effective prevention strategies for DVT are crucial.
• Graduated, static, external compression is a potential DVT prophylaxis method.

Purpose of the Study:

• To determine the optimal pressure range for graduated, static, external compression of the lower limb.
• To evaluate the effects of different compression pressures on deep venous velocity, calf muscle blood flow, and subcutaneous tissue flow.

Main Methods:

• Utilized a five-chambered pneumatic vinyl sleeve for graduated compression.
• Measured deep venous velocity (using technetium-99), calf muscle blood flow (using xenon-133), and subcutaneous tissue flow (using sodium-24).
• Assessed four different pressure ranges in recumbent patients.

Main Results:

• A pressure range of 18, 14, 8, 10, 8 mmHg significantly increased mean deep venous velocity (P < 0.02).
• This optimal pressure range did not impair calf muscle blood flow or subcutaneous tissue flow.
• A higher pressure range (30, 26, 14, 18, 12 mmHg) increased deep venous velocity but significantly impaired calf subcutaneous tissue flow.

Conclusions:

• The pressure range of 18, 14, 8, 10, 8 mmHg represents an optimal setting for graduated, static, external compression.
• This compression strategy effectively enhances deep venous velocity without compromising crucial tissue perfusion.
• Careful selection of compression pressure is vital to avoid adverse effects on subcutaneous tissue blood flow.