Percutaneous Abscess Drainage

Anatomy and Physiology

When the body develops an infection, depending on the causative organisms, there is the possibility of localized abscess formation. As part of the body's immune response, the infection may become walled off by granulation tissue and inflammatory cells, creating a barrier to contain the spread of pathogens. This encapsulation allows purulent material, composed of dead immune cells (primarily neutrophils), infectious organisms, necrotic tissue, and debris, to accumulate within a defined cavity.

Fluid collections and abscesses can form almost anywhere in the human body to which microorganisms, specifically bacteria, have access. The propensity for abscess formation depends on local tissue vascularity, immune surveillance, and the host's ability to mount a response. Skin and soft tissue are common sites for the development of abscesses, especially in cases of cellulitis, folliculitis, or postsurgical infections.

Other frequent locations include intraabdominal organs and compartments, such as the liver (pyogenic liver abscess), pancreas (potpancreatitis collections), and sigmoid colon, especially in diverticulitis where a diverticular abscess develops. Additionally, in complicated appendicitis, an abscess can form, or the appendix can rupture, leading to peritonitis or abscess formation in the right lower quadrant.[7] Pelvic abscesses can also occur postoperatively or due to gynecological infections.

Understanding the anatomic compartments and the natural pathways of fluid spread is crucial for accurate diagnosis and successful image-guided drainage. For example, retroperitoneal abscesses may be harder to detect and access than intraperitoneal ones, and interventional planning must take into account adjacent structures and potential complications.[8][9]

Indications

In a wide range of clinical scenarios, image-guided percutaneous catheter drainage is indicated where noninvasive management is inadequate or inappropriate. Common indications include the following:

• Drainage of large (>3 cm) abscesses, as smaller collections may resolve with antibiotics alone and do not typically allow for safe or effective catheter placement [10]
• Multiloculated or complex abscesses, which may not be amenable to simple aspiration and require ongoing drainage to resolve [11]
• Abscesses with suspected or confirmed enteric communication, where persistent contamination may require continuous drainage [12][13]
• Failure of medical therapy, where appropriate antibiotic treatment does not result in clinical improvement [14]
• Unclear clinical diagnosis, where drainage allows both therapeutic benefit and diagnostic sampling for microbiological analysis [15]
• Patient noncompliance or inability to tolerate prolonged antibiotic therapy, making mechanical drainage a more reliable intervention
• Anatomic inaccessibility for open surgical drainage, especially in deep pelvic, retroperitoneal, or subphrenic collections

Each indication should be considered in the context of the patient’s overall clinical condition, imaging findings, and response to prior therapies. Early consultation with interventional radiology is encouraged in complex or high-risk cases.

Contraindications

Contraindications for image-guided percutaneous catheter drainage include the following:

• Uncorrectable coagulopathy
  • Patients with significant bleeding diatheses—such as an international normalized ratio (INR) >1.5 or platelet count <50,000/μL—that cannot be corrected prior to the procedure are at increased risk of hemorrhagic complications.
• Lack of a safe percutaneous window
  • If adjacent structures (eg, bowel loops, major vessels, or solid organs) prevent a safe access route, image-guided drainage may be contraindicated due to the risk of iatrogenic injury.
• Inability to cooperate with the procedure
  • Patient factors such as severe anxiety, agitation, or inability to remain still during the procedure (particularly when sedation is contraindicated) may increase procedural risk.
• Inability to provide informed consent
  • In cases where the patient lacks decision-making capacity and no surrogate decision-maker is available, proceeding without proper legal consent is ethically and legally inappropriate.
• Lesions smaller than 3 cm
  • Small abscesses may not allow sufficient space for the safe placement of wires, dilators, and catheters, increasing the risk of injury or technical failure. In such cases, conservative management may be preferable unless clinical deterioration necessitates intervention.
• Superficial skin or soft tissue infection overlying the puncture site
  • This may increase the risk of spreading infection along the catheter tract and is generally avoided.

Equipment

The following equipment is essential for the safe and effective performance of image-guided percutaneous abscess drainage:

• Drainage catheter
  • Selection is based on the abscess contents' size, location, and consistency.
    • Small-caliber catheters (8–10 French) are typically sufficient for draining simple, serous collections.
    • Larger-caliber catheters (12 French or greater) are preferred for thick, purulent, hemorrhagic, or multiloculated abscesses. They ensure adequate drainage and reduce the risk of clogging.
• Drainage bag
  • A sterile collection bag with tubing is attached to the catheter for continuous output monitoring.
• Sterile field setup
  • Includes povidone-iodine or chlorhexidine solution, fenestrated drapes, sterile gloves, gowns, and masks to maintain aseptic technique
• Scalpel (#11 or #15 blade)
  • Used to create a skin incision for catheter entry
• Imaging equipment
  • Ultrasound is preferred for superficial or easily compressible collections, offering real-time, radiation-free guidance.
  • CT guidance is ideal for deep, complex, or difficult-to-access abscesses and allows precise localization.
• Guidewire and dilator kit
  • Required if using the Seldinger technique to facilitate catheter placement
• Trocar introducer set
  • Used for the trocar technique in large, superficial abscesses
• Cardiac monitor
  • For continuous monitoring of vital signs, including heart rate, blood pressure, respiratory rate, and oxygen saturation
• Local anesthetic
  • Typically 1% lidocaine for infiltration at the puncture site
• Sutures or adhesive device
  • To secure the catheter in place postprocedure and prevent dislodgement

Personnel

Image-guided percutaneous abscess drainage can be performed by a range of trained medical professionals, depending on institutional protocols and the complexity of the case:

• Interventional radiologists are the primary specialists for this procedure. They are extensively trained in image-guided interventions and most commonly perform percutaneous abscess drainage in clinical settings.
• Surgeons and emergency medicine physicians with training in ultrasound-guided procedures may also perform drainage in appropriate cases, particularly in emergency or resource-limited environments.
• Midlevel providers, including physician assistants (PAs) and nurse practitioners (NPs), may be certified to perform or assist in the procedure under supervision, especially in settings where interventional radiology support is limited.
• Registered nurses or radiologic technologists often assist during the procedure by preparing equipment, maintaining sterility, monitoring patient status, and supporting postprocedural care.

This collaborative approach ensures the safe and effective performance of the procedure while optimizing patient outcomes.

Preparation

Proper preprocedural preparation is essential to ensure the safety and effectiveness of image-guided percutaneous abscess drainage. Key steps include:

• Obtaining informed consent from the patient or their designated healthcare proxy, including a thorough discussion of the procedure, risks, benefits, and potential alternatives.
• Reviewing relevant diagnostic studies, including recent imaging (ultrasound, CT, or magnetic resonance imaging [MRI]) to localize the abscess and assess its size, complexity, and accessibility.
• Laboratory tests should be evaluated, particularly:
  • Complete blood count (CBC)
  • Coagulation profile (including prothrombin time [PT]/international normalized ratio [INR] and platelet count)
    • Platelet count should be ≥50,000/µL
    • INR should be <1.5 to minimize bleeding risk
    • Hemoglobin should ideally be >9.0 g/dL, particularly in high-risk or anemic patients
• Any coagulopathies should be corrected prior to the procedure to mitigate bleeding risk.
• Administration of intravenous antibiotics may be indicated preprocedurally, especially if the abscess is large, infected, or associated with systemic signs of infection. If microbiologic sensitivities are not yet available, a broad-spectrum empiric antibiotic should be chosen based on the anatomical location of the abscess and the most likely pathogens (eg, gram-negative bacilli, anaerobes, or Staphylococcus aureus).[16]
• Establishing intravenous (IV) access and confirming patient fasting status (if sedation is planned) are also important preparation components.

Technique or Treatment

There are 2 commonly used techniques for percutaneous drainage: the Seldinger and trocar techniques. The choice between them depends primarily on the abscess's size, depth, and location. The Seldinger technique is preferred for small, deep, high-risk, or difficult-to-access abscesses, while the trocar technique is typically used for larger, more superficial collections.

The patient is positioned appropriately on the table and connected to monitors for continuous vital sign monitoring. An IV line is placed for sedation and fluid administration if required. The procedure site is cleaned and prepped using standard sterile technique. The decision to use local anesthesia, conscious sedation, or both depends on the patient's condition, provider preference, and procedural complexity. Local anesthesia improves comfort and compliance, while conscious sedation may be indicated for prolonged or particularly painful procedures.

A small skin incision is made to facilitate catheter placement. In the Seldinger technique, initial access to the abscess cavity is obtained using a 21- or 22-gauge needle. A coaxial catheter system is then used to introduce a 0.018-inch guidewire, which is subsequently exchanged for a 0.035- or 0.038-inch wire to accommodate the drainage catheter.

In the trocar technique, a small-gauge needle is used for the initial aspiration of abscess contents to confirm proper positioning. A coaxial combination catheter is then inserted parallel to the needle, allowing for direct advancement of the drainage catheter into the fluid collection.

Once in place using either technique, the catheter is connected to an external drainage bag, often employing negative pressure systems to facilitate continuous drainage. The catheter remains in situ until the abscess or collection is adequately evacuated, typically taking several days.[17]

Complications

While generally safe and minimally invasive, percutaneous abscess drainage is not without risk. Site-specific and systemic complications can occur and should be considered before the procedure:

• Pain
  • Mild to moderate pain at the catheter insertion site is common and usually managed with oral analgesics. Persistent or worsening pain may indicate inadequate drainage or secondary infection.
• Infection
  • Although the procedure is performed under sterile conditions, secondary or catheter-related infection may occur. Proper catheter care and monitoring can help reduce this risk.
• Bleeding
  • Hemorrhage is a rare but serious complication, particularly in patients with underlying coagulopathies or when vascular structures are inadvertently injured during catheter insertion.
• Injury to adjacent structures
  • Depending on the abscess location, there is a risk of damage to nearby organs or tissues, such as the bowel, liver, or vascular structures, especially during deep or retroperitoneal drainage.
• Incomplete drainage or catheter blockage
  • Viscous or loculated fluid collections may not drain fully, leading to the need for catheter repositioning, replacement, or escalation to surgical management.
• Catheter dislodgement or malfunction
  • Premature removal or migration of the catheter can lead to the recurrence of the abscess or incomplete resolution.
• Fistula formation
  • Rarely, especially in cases involving enteric communication, a persistent fistula may form, requiring long-term drainage or surgical intervention.

Prompt recognition and management of these complications are essential to minimize morbidity and ensure successful outcomes.[18]

Clinical Significance

Abscesses, particularly when deep-seated or located in anatomically complex regions, can lead to severe morbidity and mortality due to the risk of sepsis, organ dysfunction, or systemic dissemination of infection. In critically ill patients, image-guided percutaneous drainage offers a minimally invasive alternative to open surgical intervention, enabling effective source control while minimizing physiological stress. By avoiding general anesthesia, particularly in high-risk patients with comorbidities, this technique may lead to shorter hospital stays, faster recovery, and reduced healthcare costs.

Moreover, percutaneous drainage supports antibiotic stewardship. Many abscesses, especially those without systemic signs of infection, can be effectively managed through drainage alone without prolonged antibiotic therapy. This approach helps reduce unnecessary antibiotic use, thereby minimizing the risk of antimicrobial resistance and associated complications.

However, antibiotics should be administered in conjunction with drainage in patients presenting with systemic signs of infection, including fever, chills, elevated white blood cell count, or hemodynamic instability. Patient-specific factors such as diabetes mellitus, intravenous drug use, immunosuppression, or a history of resistant organisms(eg, MRSA) should guide the selection of empiric and definitive antimicrobial therapy.

Early recognition, accurate localization, and timely drainage of abscesses, guided by imaging, play a pivotal role in improving patient outcomes, reducing complications, and preserving organ function.

Enhancing Healthcare Team Outcomes

Effective management of percutaneous abscess drainage requires a coordinated, interprofessional approach to optimize patient-centered care, enhance outcomes, and ensure patient safety. Physicians, including interventional radiologists and surgeons, play a key role in procedural planning, selecting the appropriate drainage technique, and determining when surgical intervention is necessary. Advanced practitioners and nurses assist in pre-procedure patient education, monitoring for complications, and providing post-procedure wound care. Pharmacists contribute by ensuring appropriate antibiotic selection based on culture results and patient-specific factors, optimizing antimicrobial stewardship, and preventing adverse drug interactions.

Interprofessional communication is essential for seamless care coordination, particularly in recognizing signs of inadequate drainage, persistent infection, or sepsis, which may require escalation of care. Nurses and advanced practitioners monitor vital signs, drainage output, and signs of infection, promptly communicating any concerns to the primary team. Rehabilitation specialists may be involved in cases where prolonged immobility or underlying conditions require physical therapy. By fostering teamwork, utilizing evidence-based protocols, and maintaining open communication, healthcare professionals can improve patient safety, minimize complications, and ensure effective abscess resolution.

Nursing, Allied Health, and Interprofessional Team Interventions

Nurses and allied health professionals are vital in facilitating percutaneous abscess drainage by preparing the patient, assisting with intraprocedural support, and educating the patient on post-procedure care. They also help coordinate interdisciplinary care, ensure sterile technique, and administer prescribed medications such as analgesics or antibiotics.

Nursing, Allied Health, and Interprofessional Team Monitoring

Postprocedure monitoring involves regular assessment of the drainage site for signs of infection, proper catheter function, and fluid output. Nurses and allied health staff are essential in tracking vital signs, reinforcing follow-up schedules, and promptly communicating complications to the treating team to support optimal recovery.