From the Guidelines
Unna boots are a recommended treatment for managing edema, particularly in cases of venous stasis ulcers and lymphedema, due to their ability to provide sustained compression and support to the affected limb. To use an Unna boot effectively, it is essential to follow proper application and care instructions. First, ensure the skin is clean and dry, then elevate the limb for 15-20 minutes before application to reduce existing swelling 1. The boot consists of a gauze bandage impregnated with zinc oxide paste, calamine, and other soothing ingredients. Apply the Unna boot by wrapping it around the affected area in a spiral pattern, starting at the foot and working upward to just below the knee, with 50% overlap between layers. Maintain even pressure throughout without being too tight, as this could impair circulation.
Key Considerations for Unna Boot Usage
- The minimum pressure recommended for compression therapy is 20 to 30 mm Hg, with pressures of 30 to 40 mm Hg advised for more severe disease 1.
- Improved ejection fraction in refluxing vessels and higher extrinsic pressures were achieved when higher pressures were exerted at the calf over the distal ankle (negative graduated compression bandage) 1.
- Adherence to compression therapy should be encouraged with proper fitting, education, and detailed instructions 1.
- Caution is advised when the ankle-brachial index is <0.6, as it indicates an arterial anomaly needing revascularization 1. Once applied, cover the Unna boot with an elastic bandage for additional compression and protection. The boot typically remains in place for 5-7 days, depending on the severity of edema and clinical response. Patients should keep the boot dry, monitor for signs of skin irritation or circulation problems (numbness, increased pain, discoloration of toes), and elevate the limb when possible. The boot works by creating sustained compression that helps move excess fluid back into circulation while the zinc oxide provides anti-inflammatory benefits. Unna boots are particularly useful for venous stasis ulcers and lymphedema but should be applied by trained healthcare professionals, especially for initial applications.
From the Research
Unna Boot Usage for Edema
- The Unna boot is a type of compression therapy used to treat edema and venous leg ulcers 2.
- It is a non-invasive and ambulatory method of controlling edema and treating ulcers in chronic venous insufficiency (CVI) 2.
- The Unna boot is a functional substitute for the failing muscle pump in CVI, and it does not interfere with patients' activities 2.
Instructions for Use
- A manual on the technique of applying the Unna boot in patients with venous leg ulcers has been developed and validated for content by an expert panel 3.
- The manual includes 29 pages of text and illustrations, as well as a video demonstration of the technique 3.
- The application of the Unna boot involves the use of a paste bandage, a compression bandage, and a stocking 3.
Effectiveness
- The Unna boot has been shown to be effective in controlling edema and treating venous leg ulcers 2, 4.
- A systematic review and meta-analysis found that the Unna boot was associated with a moderate degree of evidence for no difference in healing rates of venous leg ulcers 4.
- Another study found that the use of the Unna boot was associated with a healing rate of 91% for first ulcers of complaint patients 2.
Considerations
- The Unna boot is a valuable option for refractory cases of limb edema in advanced disease, particularly when combined with diuretic therapy 5.
- The use of the Unna boot should be considered in conjunction with other treatments, such as compression therapy and wound care 6, 4.
- Further research is needed to fully understand the effectiveness and safety of the Unna boot in the treatment of edema and venous leg ulcers 4.