What is the management for an abscess that yields only bloody drainage after drainage?

Management of Abscess with Bloody Drainage

When an abscess drainage yields only bloody drainage, re-evaluation with imaging is indicated to determine if the abscess was adequately drained, followed by repositioning of the drain or surgical intervention if needed. 1

Diagnostic Re-evaluation

When bloody drainage is encountered during abscess drainage, consider the following steps:

1. Imaging reassessment:

   • Ultrasound is preferred for superficial abscesses to differentiate between hematoma and abscess 1
   • CT with IV contrast for deeper abscesses to assess location and extent 1
   • MRI for anorectal abscesses to evaluate for associated fistula tracts 1

2. Differential considerations:

   • True abscess with bloody component
   • Hematoma misdiagnosed as abscess
   • Vascular lesion
   • Inadequate drainage with residual abscess pocket

Management Algorithm

Step 1: Immediate Actions

• Ensure hemostasis if active bleeding is present
• Obtain imaging to reassess the collection:
  • Ultrasound for superficial collections
  • CT scan for deeper collections or complex cases 2, 1

Step 2: Based on Imaging Findings

If residual abscess is present:

• Reposition existing drain or place additional drain under imaging guidance 1
• Consider surgical drainage if percutaneous approach is inadequate 2

If collection is primarily a hematoma:

• Monitor for signs of infection
• Consider evacuation only if symptomatic or expanding 1

If no residual collection:

• Remove drain
• Continue antibiotics if clinically indicated 2

Antibiotic Therapy

Antibiotics are indicated in the following scenarios:

• Presence of systemic infection or sepsis
• Surrounding soft tissue infection
• Immunocompromised patient 2
• Inadequate source control 1

Antibiotic recommendations:

• For immunocompetent patients: 4-day course if source control is adequate 1
• For immunocompromised patients: Up to 7-day course based on clinical condition 1
• Consider MRSA coverage as prevalence can be up to 35% in some locations 2, 1

Post-Procedure Monitoring

1. Clinical monitoring:

   • Vital signs
   • Pain assessment
   • Wound examination

2. Laboratory monitoring:

   • Inflammatory markers (CRP, WBC)
   • Procalcitonin if initially elevated 1

3. Follow-up imaging:

   • Consider repeat imaging if clinical improvement is not observed within 48-72 hours 1

Special Considerations for Anorectal Abscesses

For anorectal abscesses specifically:

• Surgical drainage is the primary treatment 2
• Evaluate for associated fistula but avoid probing to search for fistula to prevent iatrogenic complications 2
• If fistula is present:
  • For low fistula not involving sphincter muscle: Consider fistulotomy at time of drainage 2
  • For fistula involving sphincter muscle: Place loose draining seton 2

Wound Care

• Clean with warm water/saline 2-3 times daily
• Consider sitz baths for perianal abscesses
• Use non-adherent absorbent dressings
• For deeper wounds, consider alginate or hydrofiber dressings 1

Follow-up

• First follow-up within 48-72 hours after drainage
• Subsequent follow-ups every 1-2 weeks until complete healing
• Monitor for signs of:
  • Recurrent abscess formation
  • Development of fistula
  • Delayed healing
  • Persistent infection 1

Pitfalls and Caveats

• Bloody drainage may indicate inadequate localization of the abscess cavity
• Failure to recognize a hematoma misdiagnosed as abscess can lead to unnecessary interventions
• Inadequate drainage is a common cause of treatment failure and recurrence
• Avoid probing anorectal abscesses for fistulas to prevent iatrogenic complications 2
• Consider underlying conditions that may predispose to recurrent abscesses (e.g., Crohn's disease, immunodeficiency) 2