What is DAIR (Debridement, Antibiotics and Implant Retention)?
Debridement, Antibiotics, and Implant Retention (DAIR) is a treatment strategy used primarily for managing prosthetic joint infections (PJIs) in hip and knee arthroplasty. This approach aims to preserve the existing implant while addressing the infection through a combination of surgical and antibiotic interventions.
Indications for DAIR (Debridement, Antibiotics and Implant Retention)
The DAIR procedure is typically considered for acute or early-onset infections (within a few weeks to a few months after surgery) where the implant is well-fixed and there are no signs of significant loosening or abscess formation. The success of DAIR depends on various factors, including the timing of the intervention, the virulence of the infecting organism, the patient's overall health, and the adequacy of the debridement and antibiotic therapy.
Preparation for DAIR (Debridement, Antibiotics and Implant Retention)
In general, preparation for the DAIR procedure may involve the following:
- Clinical examination, laboratory tests (such as elevated ESR and CRP levels), and imaging studies (like X-rays or MRI) to confirm the presence of infection.
- Joint aspiration or tissue biopsy may be performed to identify the causative microorganisms and their antibiotic sensitivities.
- A comprehensive medical evaluation, including a review of your medical history, medical conditions, allergies, and current medications/supplements.
- Instructions on avoiding certain medications and supplements that can thin the blood and increase the risk of bleeding during surgery.
- Instructions on fasting before surgery, stopping smoking, and limiting alcohol consumption.
- A signed informed consent form will be obtained from you after the risks and benefits of the surgery have been explained.
Procedure for DAIR (Debridement, Antibiotics and Implant Retention)
In general, the DAIR procedure may involve the following steps:
- Surgical Debridement
- Anesthesia: The patient is given either general or regional anesthesia.
- Incision and Exposure: The surgeon reopens the original surgical incision to access the joint.
- Removal of Infected Tissue: All infected and necrotic tissue around the implant is carefully removed. This includes excising the infected synovium (joint lining) and any other infected soft tissues.
- Joint Irrigation: The joint space is thoroughly irrigated with large volumes of sterile saline solution, often containing antiseptic agents, to flush out bacteria and debris.
- Antibiotic Therapy
- Systemic Antibiotics: Intravenous antibiotics are administered based on the culture and sensitivity results of the bacteria causing the infection. This helps to ensure that the chosen antibiotics are effective against the specific pathogen.
- Local Antibiotics: In some cases, antibiotic-impregnated materials (such as beads or cement) may be placed around the joint to provide high local concentrations of antibiotics directly to the infected area.
- Implant Retention
- Inspection of the Implant: The surgeon carefully inspects the prosthetic components. If they are well-fixed and there is no significant damage or loosening, they are retained.
- Biofilm Management: Efforts are made to disrupt and remove any biofilm (a protective layer of bacteria) on the implant surfaces through mechanical debridement and antiseptic solutions.
- Exchange of Modular Components: In many cases, modular components of the prosthesis (such as the femoral head in hip replacements or the polyethylene liner in knee replacements) are exchanged to further reduce the bacterial load and improve outcomes.
- Wound Closure
- Layered Closure: Finally, the surgical wound is closed in layers to ensure proper healing. Drains may be placed to prevent fluid accumulation and reduce the risk of infection.
- Sterile Dressing: A sterile dressing is applied to the wound to protect it and promote healing.
Postoperative Care and Recovery
In general, postoperative care and recovery for DAIR procedure may include:
- After the surgery, the patient will be transferred to the recovery room where they will be closely monitored as they wake up from anesthesia.
- It is common to experience pain and swelling around the treatment area. Medications are provided as needed to address these.
- Patients typically receive a prolonged course of antibiotics, often starting with intravenous administration followed by oral antibiotics. The total duration of antibiotic therapy can range from several weeks to several months, depending on the severity and type of infection.
- Incision care instructions are provided to keep the incision site clean and dry.
- Avoid strenuous activities, such as exercise and heavy lifting during the healing period to facilitate recovery.
- Physical therapy may be recommended to restore joint function and mobility.
- Regular follow-up appointments will be scheduled to monitor the patient's response to treatment, check for signs of persistent or recurrent infection, and ensure proper joint function and healing.
Risks and Complications
Risks and complications associated with the DAIR procedure include:
- Infection recurrence
- Antibiotic resistance
- Implant failure
- Wound healing issues
- Bleeding
- Damage to surrounding tissues
- Allergic/anesthetic reactions
Advantages
Some of the benefits associated with the DAIR procedure include:
- Preservation of the original implant, avoiding the need for more extensive revision surgery
- Shorter recovery time compared to implant removal and replacement
- Potentially lower overall treatment costs
- Minimally invasive
- Less pain and discomfort
- Effective infection control
- Patient-specific treatment