Rectus Sheath Hematoma and Pneumonia
Pneumonia does not directly cause rectus sheath hematoma, but severe coughing associated with pneumonia can trigger this condition through mechanical strain on the rectus abdominis muscle.
Mechanism of Pneumonia-Related Rectus Sheath Hematoma
The connection between pneumonia and rectus sheath hematoma is indirect but clinically recognized:
Coughing as the precipitating factor: Violent or persistent coughing from pneumonia creates sudden increases in intra-abdominal pressure and forceful contraction of the rectus abdominis muscle, which can rupture the superior or inferior epigastric arteries 1, 2.
Muscular strain mechanism: Acute abdominal pain and a palpable mass after muscular strain such as coughing, sneezing, and twisting are features highly suggestive of rectus sheath hematoma 2.
Clinical case evidence: A documented case describes a patient who developed rectus sheath hematoma after being treated for community-acquired pneumonia, demonstrating this association in real-world practice 1.
Key Predisposing Factors to Consider
When evaluating a patient with pneumonia for potential rectus sheath hematoma, assess these critical risk factors:
Anticoagulation status: The use of anticoagulants (warfarin, DOACs, heparin) or antiplatelet agents dramatically increases risk and is the most common predisposing factor 1, 3, 4.
Age and vascular disease: Elderly patients with atheromatous changes in epigastric vessels are at higher risk for spontaneous bleeding even without anticoagulation 3, 2.
Previous abdominal surgery or trauma: Prior operations on the lower abdomen or recent trauma increase vulnerability 4.
Female sex: Women appear to be disproportionately affected in case series 4.
Clinical Presentation
Look for these specific findings when pneumonia patients develop abdominal complaints:
Acute unilateral abdominal pain: Typically in the lower quadrants, often right-sided, with a palpable tender mass 1, 2.
Carnett's sign: Pain that increases (rather than decreases) with tensing of the abdominal wall muscles, distinguishing this from intraperitoneal pathology 5.
Hemodynamic instability: Tachycardia, hypotension, and dropping hemoglobin indicate active bleeding requiring urgent intervention 1.
Bladder symptoms: Difficulty voiding, nausea, and vomiting may occur with large hematomas 1.
Diagnostic Approach
CT scan with and without contrast is the diagnostic modality of choice for confirming rectus sheath hematoma 6, 1, 4:
CT accurately defines the location, size, and extent of the hematoma, including extension into preperitoneal space 1.
Ultrasound may aid in diagnosis but is less accurate than CT for defining the lesion 4.
Monitor hemoglobin levels serially to detect ongoing bleeding 6.
Management Algorithm
Hemodynamically Stable Patients
Conservative management is appropriate for most cases 6, 3:
Close monitoring of vital signs and serial hemoglobin measurements 6.
Hemostatic agents including tranexamic acid and carbazochrome can control bleeding expansion 3.
Reversal of anticoagulation when appropriate, using specific reversal agents based on the anticoagulant used 6.
Compression of the hematoma site may be helpful in some cases 6.
Hemodynamically Unstable Patients or Progressive Bleeding
Interventional radiology embolization is the preferred invasive approach 6:
Embolization of the bleeding epigastric artery (superior or inferior) should be performed after correcting coagulopathy 1.
Coagulopathy reversal should be TEG-guided and may include platelets, cryoprecipitate, PCC/FFP, and PRBCs 1.
Surgical Intervention
Surgical evacuation is indicated only in cases of failed embolization 6 or when abdominal compartment syndrome develops:
Monitor bladder pressures; pressures in the 30s mmHg indicate compartment syndrome requiring urgent surgical decompression 1.
Surgical options include decompression, extraperitoneal packing, and temporary closure followed by definitive repair after stabilization 1.
Critical Pitfalls to Avoid
Misdiagnosis as intra-abdominal pathology: Rectus sheath hematoma can mimic appendicitis, diverticulitis, or other surgical emergencies, leading to unnecessary laparotomy 2, 5.
Delayed recognition in anticoagulated patients: The incidence of rectus sheath hematoma is increasing with greater anticoagulant use; maintain high clinical suspicion in this population 1, 5.
Premature intervention before coagulopathy correction: Attempting embolization or surgery before reversing anticoagulation can worsen bleeding 1.
Underestimating severity: Large hematomas below the arcuate line (where posterior rectus sheath is absent) can spread extensively and cause life-threatening complications 1.