What is the levine technique? A Guide to Proper Wound Swabbing

September 21, 2025 •

4 min read

Research indicates that the Levine technique is superior to other swab methods for detecting bacteria in infected wounds. This article explains what is the Levine technique and why its precise methodology is critical for effective wound care, reducing the risk of false results caused by surface contamination.

Quick Summary

The Levine technique is a precise method for collecting a wound culture sample by rotating a swab over a cleansed, 1cm² area of the wound bed with enough pressure to express fluid from deeper tissue layers.

Key Points

Deep Tissue Sampling: The Levine technique uses pressure to extract fluid from deep within the wound tissue, not just the surface.
Superior Accuracy: Studies show it is more effective at detecting bacteria in both acute and chronic infected wounds compared to other swab methods.
Standardized Procedure: It requires sampling a specific 1 cm² area of cleansed, viable tissue, ensuring consistency and preventing contamination from surface debris.
Informed Treatment: Accurate culture results from this technique allow for targeted and effective antibiotic treatment, preventing unnecessary or incorrect therapy.
Essential Skill: It is a fundamental and best-practice skill for healthcare professionals involved in the diagnosis and management of wound infections.

Understanding the Purpose of a Wound Culture

Accurate wound management relies on identifying the specific microorganisms causing an infection. A wound culture is the diagnostic tool used to determine the type of bacteria present, which in turn guides the most effective antibiotic treatment. While tissue biopsy is the most accurate method, it is also invasive and costly. Therefore, wound swabbing is the most common, cost-effective, and non-invasive alternative. However, not all swabbing methods are created equal. The Levine technique was developed to overcome the limitations of older methods, which often sampled only surface-level contaminants rather than the bacteria within the wound tissue itself.

The Importance of the Levine Technique

The key to the Levine technique's superiority lies in its methodology. By applying consistent pressure and focusing on a specific, clean area of the wound bed, it ensures a sample is collected from the deeper, more representative fluid of the wound, not just superficial debris. This significantly increases the accuracy of the culture results, allowing for a more targeted and effective treatment plan. Improper swabbing techniques can lead to inaccurate results, potentially causing incorrect antibiotic use, delayed healing, or even worsening of the infection.

Step-by-Step Procedure for the Levine Technique

Following a sterile protocol is paramount when performing the Levine technique to avoid contamination. Here is a detailed, step-by-step guide for healthcare professionals:

Preparation: Gather all necessary supplies, including a sterile wound swab with a transport medium, sterile normal saline, sterile gauze, sterile gloves, and a biohazard transport bag.
Hand Hygiene and PPE: Perform meticulous hand hygiene. Don sterile or clean gloves to maintain a sterile field around the wound.
Wound Cleansing: Gently irrigate the wound bed with sterile normal saline to remove any excessive exudate and superficial debris. This step is critical for preventing the collection of contaminants. Pat the area dry with sterile gauze, but do not wipe away the fluid from within the wound tissue.
Identify Sample Site: Select a 1 cm² area of clean, viable tissue within the wound bed. This should not be from the wound edge, eschar, or necrotic material.
Swab Collection: Take the sterile swab and place it on the chosen 1 cm² area. Rotate the swab over this spot for 5 seconds while applying sufficient pressure to express fluid from the wound bed. This pressure is what distinguishes the Levine technique and ensures a deep tissue sample.
Specimen Handling: Immediately place the swab into its sterile collection container with transport medium. Ensure the swab does not touch any other surface, including your gloves.
Label and Document: Label the specimen tube with the patient's information, date, time of collection, and wound location. Document the procedure in the patient's record.

Levine Technique vs. Other Swab Methods

The Levine technique is often compared to other methods, such as the Z-stroke technique. A comparison highlights why the Levine method is the preferred clinical standard.


Feature	Levine Technique	Z-Stroke Technique
Sampling Area	Focuses on a specific 1 cm² area of the wound bed.	Uses a zigzag pattern across the entire wound surface.
Pressure Applied	Sufficient pressure to extract fluid from deep tissue.	Lighter pressure, collecting primarily from the surface.
Sample Quality	Better at detecting the true bacterial burden within the wound tissue.	Prone to collecting superficial contaminants, leading to less accurate results.
Accuracy	Significantly superior for both acute and chronic wounds.	Less effective at identifying underlying infection, resulting in lower sensitivity.

Indications and Best Practices

The Levine technique is the indicated method for collecting a wound culture when a local or spreading infection is suspected. This includes acute wounds with classic signs of infection (e.g., redness, swelling, warmth, pain) or chronic wounds showing signs of delayed healing, increasing size, or changes in exudate.

For optimal results, consider these best practices:

Timing: Collect the specimen before beginning antibiotic therapy, if possible, to get the most accurate baseline culture. Antibiotics can skew the results.
Debridement: If excessive debris or necrotic tissue is present, conservative sharp debridement may be necessary before swabbing to ensure the sample is taken from viable tissue.
Consistency: Always follow the protocol precisely. Even slight deviations can compromise the sample and its accuracy.

Conclusion: The Gold Standard for Wound Culture

The Levine technique represents a critical evolution in wound care diagnostics, moving beyond unreliable surface sampling to a method that provides a more accurate picture of a wound's true bacterial load. For healthcare providers, mastering this technique is not just about following a procedure, but about ensuring patient safety and promoting efficient healing through precise, evidence-based treatment. Its proven superiority over less rigorous methods makes it the gold standard for collecting wound cultures and an indispensable skill for anyone involved in managing infected wounds. Learn more about best practices in wound care from authoritative resources like WoundReference.

Frequently Asked Questions

The main difference is the sampling method. The Levine technique samples a small, specific area with pressure to extract deep fluid, while the Z-stroke technique involves swabbing the wound surface in a zigzag pattern, which is more prone to picking up surface contaminants rather than actual infection-causing bacteria.

You should select a 1cm² area of clean, viable tissue. Avoid areas with necrotic tissue, eschar, or excessive pus and avoid the wound edges, as these spots are more likely to contain surface contaminants that will produce less accurate results.

Cleansing the wound with normal saline removes superficial debris and exudate. This ensures that the swab collects a sample representative of the organisms causing the infection within the tissue, rather than those simply colonizing the wound's surface.

The technique is a form of swabbing and is less invasive than a biopsy. While it involves applying pressure, it should not be painful. Proper preparation and gentle technique are important for patient comfort.

The Levine technique is best suited for open wounds that are large enough to identify a 1 cm² area of viable tissue. It is not appropriate for wounds where the tissue is approximated, such as some surgical incisions.

Forgetting to apply pressure means you are essentially performing a less reliable surface swab. The sample collected would primarily consist of surface contaminants, which could lead to inaccurate culture results and potentially misguide the treatment plan.

It is considered the gold standard among swabbing techniques because it has been clinically proven to have higher diagnostic accuracy compared to older methods. Its effectiveness in sampling the deep tissue fluid provides a more reliable assessment of the actual microbial burden.