Can a groin hematoma cause or exacerbate anemia in an elderly male patient with mild anemia and slightly elevated PT, scheduled for knee replacement surgery?

Can a Groin Hematoma Cause Anemia?

Yes, a groin hematoma can absolutely cause or worsen anemia in this elderly male patient, and this must be urgently evaluated and managed before proceeding with knee replacement surgery given his cardiovascular disease and coagulopathy.

Direct Mechanism of Hematoma-Induced Anemia

• A groin hematoma represents sequestered blood loss that directly reduces circulating hemoglobin levels, functionally equivalent to surgical or traumatic blood loss 1
• The volume of blood contained within a large groin hematoma can range from several hundred milliliters to over a liter, sufficient to drop hemoglobin by 1-3 g/dL or more 1
• With his slightly elevated PT (coagulopathy), this patient is at higher risk for ongoing expansion of the hematoma and progressive blood loss 2

Critical Preoperative Risk Assessment

• Preoperative anemia is present in approximately 24% of elective hip/knee arthroplasty patients and dramatically increases transfusion requirements and complications 1
• Patients with preoperative anemia have significantly higher rates of postoperative infection, blood transfusion needs (34.5% vs 5.6%), and prolonged hospital stays (6.48 vs 3.36 days) 3, 4
• In patients with cardiovascular disease and preoperative hemoglobin 6-9 g/dL, the adjusted odds ratio for mortality is 12.3 (95% CI 2.5-62.1) compared to those with hemoglobin >12 g/dL 1

Immediate Evaluation Protocol

• Measure the hematoma dimensions and perform urgent hemoglobin/hematocrit testing to quantify current anemia severity 2, 5
• Assess for active expansion by serial measurements over 6-12 hours, as ongoing bleeding with elevated PT poses surgical contraindication 2
• Rule out retroperitoneal extension with CT imaging if the hematoma is large or the patient shows disproportionate hemodynamic changes 2
• Check iron studies, ferritin, and reticulocyte count to distinguish acute blood loss from chronic iron deficiency anemia 1, 6

Management Algorithm Before Surgery

If hemoglobin <13 g/dL (which is likely given "mild anemia"):

• Delay elective knee replacement by 4-6 weeks to optimize hemoglobin levels 3, 7
• Initiate oral iron supplementation (ferrous sulfate 256 mg/day providing 80 mg elemental iron) plus vitamin C (1000 mg/day) and folic acid (5 mg/day) for 30-45 days preoperatively 7
• This protocol reduces transfusion rates from 32% to 5.8% in knee replacement patients 7
• Consider intravenous iron if oral supplementation is poorly tolerated or rapid correction is needed, as it overcomes hepcidin-induced blockade in inflammatory states 1, 6

If hemoglobin <10 g/dL:

• Surgery should be postponed and more aggressive intervention pursued 2, 5
• Add erythropoiesis-stimulating agents (ESAs) to iron supplementation for faster hemoglobin recovery 6
• Transfusion may be necessary if hemoglobin <8 g/dL or symptomatic anemia develops, particularly given his cardiovascular disease 1, 2

Coagulopathy Management

• Correct the elevated PT before any surgical intervention 2
• Hold anticoagulation (if applicable) until PT normalizes and hematoma stabilizes 2
• Vitamin K administration may be indicated depending on the cause of PT elevation 2

Expected Surgical Blood Loss Context

• Major orthopedic surgery causes an average hemoglobin drop of 3.0 g/dL, with mean blood loss of 1,004 mL in hip/knee arthroplasty 1, 8
• Starting surgery with existing anemia means postoperative hemoglobin will likely fall to critically low levels (potentially <7-8 g/dL), necessitating transfusion 1, 5
• Postoperative anemia prevalence reaches 51% after elective arthroplasty in non-anemic patients, and would be substantially higher starting from a baseline of anemia 1

Critical Pitfall to Avoid

• Do not proceed with elective knee replacement without addressing both the hematoma and underlying anemia 3, 4
• Ignoring preoperative anemia results in 6-fold higher transfusion rates and doubles the risk of postoperative complications including infection 3, 4
• Patients with cardiovascular disease experiencing hematocrit <28% (hemoglobin <9.3 g/dL) have significantly increased risk of myocardial ischemia and cardiac events 1