An occlusive dressing is a specialized medical material designed to create a complete seal over a wound, preventing the passage of air and moisture into or out of the injury site. This airtight barrier serves two main purposes: maintaining a moist environment that promotes faster cellular healing, and sealing traumatic injuries from the external atmosphere. By preventing the wound from drying out, the dressing accelerates epithelialization, the process by which new skin grows over the wound. The sealed microenvironment also provides protection against external contaminants, such as bacteria and debris.
Wound Types Requiring Occlusion
Occlusive dressings are indicated for wounds requiring moisture retention or a complete seal for proper healing. One serious application is managing a penetrating chest injury, often called a sucking chest wound. In this trauma, the dressing prevents outside air from entering the chest cavity, which can lead to a collapsed lung or a dangerous buildup of pressure called a tension pneumothorax.
Beyond emergency trauma, these dressings manage chronic wounds, such as pressure ulcers or diabetic foot ulcers, which benefit from a moist wound bed. Hydrocolloid or hydrogel dressings help retain the natural fluid and growth factors released by the wound to speed up tissue repair. Minor burns, surgical incisions, and abrasions also frequently receive occlusive coverage to retain moisture and limit the formation of a dry scab, which slows the healing process.
Necessary Supplies and Site Preparation
Proper application requires the right materials and ensuring the wound site is ready to accept the seal. Necessary supplies include:
- Non-latex or sterile gloves.
- A wound cleansing solution, such as sterile saline or mild soap and water.
- Absorbent gauze to manage excess fluid.
- The occlusive material itself (e.g., specialized chest seal, hydrocolloid sheet, petroleum gauze, or improvised non-porous material).
Before any dressing is placed, strict hand hygiene must be observed, followed by the donning of gloves to minimize the risk of infection. The wound site and the surrounding skin must be gently cleaned to remove debris, blood, or excess wound fluid, as these interfere with the dressing’s ability to adhere and create an airtight seal. Ensure the skin immediately surrounding the wound is dry; if the area is excessively hairy, the hair may need to be carefully trimmed to allow for firm adhesion.
Step-by-Step Application Technique
Once the site is clean and dry, the occlusive material is placed directly over the wound. The dressing should extend at least two inches beyond the edges of the injury in all directions to ensure an effective barrier on the surrounding healthy skin. Center the material over the wound, then remove any backing to expose the adhesive surface.
General Application and Sealing
Achieving a complete, airtight seal around the entire perimeter is essential. Apply gentle, firm pressure to the dressing, starting from the center and smoothing outward to the edges. This eliminates air pockets and ensures full contact with the skin. For wounds requiring simple moisture retention, such as ulcers or surgical sites, the dressing must be secured fully on all sides.
Sucking Chest Wound Technique
The application technique for a sucking chest wound is a specialized emergency variation. If a commercial vented chest seal is unavailable, a non-vented occlusive material must be secured on only three sides, leaving one edge unsealed and facing downward. This three-sided seal acts as a flutter valve, preventing air from entering the chest cavity on inhalation while allowing trapped air or fluid to escape on exhalation. It is recommended to apply the material as the patient exhales to expel air from the chest cavity before the seal is completed.
Post-Application Care and Dressing Removal
After application, the patient and wound must be monitored closely for complications. For a chest wound, check for increasing respiratory distress or worsening condition, which could indicate the one-way valve is failing and a tension pneumothorax is developing. For chronic wounds, regularly inspect the surrounding skin for signs of maceration, the softening and breakdown of tissue due to excessive moisture trapped under the seal.
Duration and Replacement
The duration an occlusive dressing remains in place varies, ranging from a few hours in trauma to several days for chronic wounds (typically 24 to 72 hours). Dressings must be changed immediately if they become compromised, soiled, or if there is excessive fluid leakage underneath the seal.
Safe Removal Technique
When removing the dressing, be gentle to avoid damaging fragile, newly formed tissue. To facilitate easy removal, moisten the edges of the dressing with sterile saline or water to loosen the adhesive bond and reduce discomfort. Slowly peel the dressing back while supporting the surrounding skin with the opposite hand to prevent unnecessary pulling or trauma to the healing wound bed. After removal, the wound is gently cleaned and assessed before a fresh dressing is applied.