Rectus Sheath Hematoma: Symptoms, Types, Causes and Treatment

Rectus sheath hematoma (RSH) is an under-recognized yet potentially serious cause of acute abdominal pain. It occurs when blood accumulates within the sheath of the rectus abdominis muscle—often masquerading as other abdominal emergencies, leading to diagnostic delays and, in rare cases, life-threatening complications. This comprehensive article explores the symptoms, types, causes, and treatment options for rectus sheath hematoma, drawing on clinical studies and case reports to offer a clear, patient-centered understanding.

Symptoms of Rectus Sheath Hematoma

Recognizing the symptoms of rectus sheath hematoma can be challenging because they often mimic other causes of acute abdominal pain. However, certain clinical features and examination findings can help differentiate RSH from other abdominal emergencies.

Symptom	Description	Distinguishing Feature	Source(s)
Abdominal pain	Sudden, localized or diffuse	Often worsens with movement/cough	2 3 4 6 8
Abdominal mass	Palpable, tender mass	Usually infraumbilical	5 6 13 15
Anemia	Drop in hemoglobin	May cause fatigue/weakness	1 2 3 8 13
Fever	Mild, sometimes present	May mimic infection	3 4 12

Table 1: Key Symptoms

Overview of Common Symptoms

Abdominal pain is the most frequent presenting complaint, often described as sudden and severe. The pain may be localized or diffuse, depending on the size and location of the hematoma. In some cases, the pain worsens with movement, coughing, or straining—sometimes leading to misdiagnosis as appendicitis, diverticulitis, or other acute abdominal conditions 2 3 4 8.

A palpable abdominal wall mass is another classic finding. This mass is typically tender and may be located below the umbilicus. Its presence is a critical clue distinguishing RSH from intra-abdominal pathologies 5 6 13 15.

Other symptoms can include:

• Anemia: Significant bleeding into the rectus sheath can cause a notable drop in hemoglobin, sometimes leading to fatigue, pallor, or even hypovolemic shock in severe cases 1 2 8 13.
• Fever: Low-grade fever may occur, further complicating the clinical picture and raising suspicion for infection or inflammatory abdominal processes 3 4 12.
• Nausea, vomiting, and confusion: Rare, but possible, especially in more severe cases or in the elderly 4 12.

Clinical Examination and Diagnostic Challenges

Physical examination findings can include localized tenderness, guarding, and fullness in the abdominal wall. In some instances, the abdominal wall may feel warm, and the pain may intensify with straining or coughing 2 3 4. Hematomas below the arcuate line tend to bleed more profusely and dissect tissue planes extensively, sometimes extending across the midline 3.

Due to the overlap of symptoms with other abdominal emergencies, imaging—particularly computed tomography (CT)—is essential for confirming the diagnosis 2 5 6 13.

Types of Rectus Sheath Hematoma

Understanding the types of rectus sheath hematoma is crucial for assessing severity and guiding management. Classification is generally based on the hematoma's size, location, and whether it crosses the midline or involves surrounding structures.

Type	Severity	Distinctive Features	Source(s)
Type I	Mild	Intramuscular, no fascial disruption	4 5 6
Type II	Moderate	Blood between muscle and fascia, may cross midline	1 5 13
Type III	Severe	Blood extends into peritoneum/retroperitoneum, possible hemodynamic instability	1 4 5 6 13

Table 2: Types of Rectus Sheath Hematoma

Type I: Mild and Self-limited

• Usually small and confined within the rectus muscle.
• Does not disrupt the fascial layers.
• Patients are typically stable; the hematoma resolves with conservative management 4 5 6.

Type II: Moderate Extension

• Blood collects between the muscle and the fascial sheath.
• May cross the midline but does not extend into deeper spaces.
• Patients may have a palpable mass and mild anemia; monitoring is essential 1 5 13.

Type III: Severe and Extensive

• Hematoma extends into the peritoneal or prevesical spaces.
• Often associated with significant blood loss, hemodynamic instability, and risk of hypovolemic shock.
• Surgical or interventional radiology treatment may be required 1 4 5 6 13.

Anatomical Considerations

The location of the hematoma in relation to the arcuate line is important. Above the arcuate line, tamponade by the rectus sheath limits bleeding, while below it, the absence of a posterior sheath allows hematomas to spread more extensively, increasing severity 3.

Causes of Rectus Sheath Hematoma

Rectus sheath hematoma can arise from a variety of causes, both traumatic and non-traumatic. Identifying the underlying cause is vital for management and prevention of recurrence.

Cause	Mechanism or Trigger	Risk Factors	Source(s)
Trauma	Direct injury to abdomen	Surgery, accidents	3 11 5
Anticoagulation	Impaired clotting, vessel rupture	Warfarin, heparin, DOACs	5 6 9 10 13 14 15
Sudden strain	Muscle or vessel tear	Coughing, vomiting, straining	2 3 4 9 12 15
Medical conditions	Vessel fragility, coagulopathy	Pregnancy, SLE, CKD, steroids	1 7 9 15

Table 3: Causes of Rectus Sheath Hematoma

Traumatic Causes

• Direct trauma (blunt or penetrating) to the abdominal wall is a well-established cause.
• Surgical trauma, including trocar insertion during laparoscopic procedures, increases risk 3 5 11.

Anticoagulation and Medical Therapy

• The most common predisposing factor is the use of anticoagulant therapy, such as warfarin, low-molecular-weight heparin (LMWH), or direct-acting oral anticoagulants (DOACs) 5 6 9 10 13 14 15.
• Even therapeutic doses can precipitate RSH, especially in the elderly or those with comorbidities.
• Antiplatelet agents and steroids also contribute to risk 9.

Sudden Muscular Strain

• Episodes of severe coughing, vomiting, or straining during defecation can cause sudden increases in intra-abdominal pressure, leading to muscle or vessel tears 2 3 4 9 12 15.
• Chronic constipation is a less commonly recognized but important trigger 4.

Underlying Medical Conditions

• Pregnancy increases vascular fragility and intra-abdominal pressure, predisposing to RSH 1.
• Systemic Lupus Erythematosus (SLE) and other collagen vascular disorders can create vessel fragility, even in the absence of anticoagulation 7.
• Chronic kidney disease, hypertension, and abdominal injections are additional risk factors 9 15.

Rare and Unusual Causes

• Arteriovenous malformations (AVMs) can rupture and cause spontaneous RSH 11.
• Infections and coagulopathies may contribute in rare circumstances 12.

Treatment of Rectus Sheath Hematoma

Management of rectus sheath hematoma depends on the severity of the hematoma, the patient’s clinical status, and underlying risk factors. Most cases are managed conservatively, but severe or unstable cases may require intervention.

Treatment	Indications	Outcomes/Notes	Source(s)
Conservative	Stable, mild-moderate cases	Most resolve; monitor closely	2 3 5 6 8 13 14 15
Transfusion	Significant anemia or blood loss	Needed in severe hematomas	5 6 13
Interventional radiology	Uncontrolled bleeding; hemodynamic instability	Embolization effective	11 15
Surgery	Failed conservative/interventional, ongoing instability	Rarely required, higher risk	1 5 6 8

Table 4: Treatment Approaches

Conservative Management

• Mainstay of treatment for most cases: This involves bed rest, pain control, monitoring of vital signs, and serial hemoglobin measurements 2 3 5 6 8 13 14 15.
• Cessation or reversal of anticoagulation: Temporarily stopping or reversing anticoagulant therapy (with agents like vitamin K or fresh frozen plasma) is critical in at-risk patients 10 13 14.
• Observation and supportive care: Includes intravenous fluids, correction of coagulation abnormalities, and close monitoring for complications.
• Resolution: Most patients experience gradual reabsorption of the hematoma and full recovery 2 3 8 13.

Blood Transfusion

• Indicated for patients with significant anemia, hemodynamic compromise, or large hematomas (type III) 5 6 13.
• Transfusion needs are higher in patients with severe bleeds or when anticoagulation cannot be rapidly reversed.

Interventional Radiology

• Selective embolization: For patients with ongoing bleeding not controlled by conservative measures, arteriography and selective embolization of the bleeding epigastric arteries can rapidly stop hemorrhage 11 15.
• Preferred over surgery: Lower morbidity and effective in controlling bleeding in high-risk patients.

Surgical Management

• Reserved for patients with:
  • Hemodynamic instability refractory to other treatments,
  • Ongoing or expanding hematomas causing abdominal compartment syndrome,
  • Failed embolization or inability to access interventional radiology 1 5 6 8.
• Surgical intervention carries higher risks, especially in elderly or comorbid patients.

Additional Considerations

• Resumption of anticoagulation: Not contraindicated once the hematoma has stabilized and resolved; individualized based on risk-benefit assessment 14.
• Physical therapy and ultrasound: Complementary therapies such as therapeutic ultrasound may help accelerate hematoma reabsorption, though evidence is limited 16.
• Prevention: Careful technique in abdominal procedures, judicious use of anticoagulation, and patient education about avoiding excessive straining can reduce future risk 5.

Conclusion

Rectus sheath hematoma is a rare but important cause of acute abdominal pain, often masked by symptoms resembling other abdominal emergencies. Prompt recognition, appropriate imaging, and tailored management are essential to prevent complications.

Key Points:

• Symptoms: Sudden abdominal pain, palpable mass, anemia, and sometimes fever are hallmark features.
• Types: Classified as type I (mild), type II (moderate), or type III (severe), with severity influencing management.
• Causes: Anticoagulation, trauma, sudden muscular strain, and certain medical conditions are primary triggers.
• Treatment: Most cases are managed conservatively; severe cases may require transfusion, embolization, or rarely, surgery.

Awareness of rectus sheath hematoma and a high index of suspicion—especially in patients on anticoagulation therapy or with risk factors—can facilitate early diagnosis and optimal outcomes.