Should a patient with a catfish fin injury be admitted under internal medicine (IM) or surgery?

Admission Service for Catfish Fin Injury

A patient with a catfish fin injury should be admitted under surgery, not internal medicine, as these injuries require surgical expertise for wound exploration, foreign body removal, and management of potential complications including nerve damage, retained spine fragments, and deep tissue injury.

Rationale for Surgical Admission

Nature of Catfish Injuries Requires Surgical Management

• Catfish spine injuries are penetrating trauma that commonly cause deep lacerations, foreign body embedment, and potential nerve or arterial damage requiring surgical exploration 1, 2, 3
• The pectoral and dorsal fins contain serrated venomous bony spines that frequently break off and become retained in tissue, necessitating surgical removal 4, 2, 3
• Deep penetrating injuries can cause arterial lacerations, nerve entrapment, and progressive neuropathy that may require surgical release 1, 3

Surgical Expertise is Essential for Definitive Management

• Wound exploration and irrigation are fundamental requirements for catfish injuries to identify retained foreign bodies, assess depth of penetration, and prevent complications 5
• Plain radiographs should be obtained to identify retained spine fragments, which appear as radiopaque foreign bodies requiring surgical extraction 2
• Surgical exploration may reveal fibrous tissue infiltration around nerves and vessels even when foreign bodies are absent, requiring surgical release 1

High Risk of Complications Requiring Surgical Intervention

• Secondary infections occur frequently (approximately 20% of marine animal injuries) and may involve deep structures requiring surgical debridement 4, 5
• Patients presenting with late wound care, punctures involving bone or joint, progressive inflammation, fever, or signs of sepsis require definitive surgical wound care 5
• Complications can develop over weeks to months, including progressive neuropathy with conduction block requiring surgical nerve release 1

Clinical Decision Algorithm

Immediate Assessment (Emergency Department)

• Obtain plain radiographs of the affected extremity to identify retained spine fragments 2
• Assess for signs of deep penetration: arterial injury, nerve damage, or joint/bone involvement 1, 5, 3
• Evaluate for signs of infection or systemic toxicity 4, 5

Admission Criteria Under Surgery

Admit under surgery if ANY of the following are present:

• Retained foreign body (spine fragment) visible on imaging 2
• Deep penetration requiring wound exploration 5
• Neurovascular compromise or progressive symptoms 1
• Joint or bone involvement 5
• Signs of infection requiring surgical debridement 5
• Delayed presentation (>6 hours) with ongoing symptoms 2

Why Not Internal Medicine?

• Internal medicine lacks the procedural expertise for wound exploration, foreign body removal, and nerve release 1, 2
• These injuries are fundamentally traumatic penetrating wounds requiring surgical management, not medical management 3
• Even when infection is the primary concern, surgical debridement and exploration remain essential components of treatment 5

Common Pitfalls to Avoid

• Do not underestimate the depth of penetration - catfish spines can cause deep tissue injury and nerve entrapment even without visible external damage 1
• Do not delay surgical exploration - retained spine fragments and progressive fibrosis can cause complications weeks to months later 1, 2
• Do not assume absence of foreign body on initial exam - radiographic imaging is essential as spine fragments are often retained 2
• Do not treat as simple puncture wound - these injuries require surgical wound exploration and irrigation regardless of initial appearance 5