Incidence of Hematoma Following Hip Surgery
Postoperative hematoma requiring surgical evacuation occurs in approximately 0.12% (1 in 833 cases) of primary total hip arthroplasty procedures, though the overall incidence of clinically significant hematomas is higher. 1
Overall Incidence Rates
- Surgical evacuation rate: 0.12% of primary THA cases required reoperation for hematoma based on a large national database analysis of 149,026 patients 1
- Major bleeding complications: In patients with hemophilia undergoing hip arthroplasty, major bleeding occurs in approximately 46% of total hip arthroplasty cases 2
- Deep vein thrombosis prevalence: 37% based on venogram studies, with 6% developing pulmonary embolism, though these represent thrombotic rather than hemorrhagic complications 3
Risk Factors for Hematoma Formation
Patient-Related Factors
- Obesity: BMI ≥35 increases risk 1.83-fold 1
- ASA class ≥3: Increases risk 2.11-fold 1
- Bleeding disorders: History of bleeding disorder increases risk 2.71-fold 1
- Anticoagulation therapy: Approximately 5% of hip fracture patients take warfarin, and one-third take aspirin regularly 3
- Clopidogrel use: About 4% of patients take clopidogrel, which should alert clinicians to expect marginally greater blood loss 3
Operative Factors
- Prolonged operative time: Procedures ≥100 minutes increase risk 2.03-fold 1
- General anesthesia: Increases risk 1.41-fold compared to regional techniques 1
- Blood loss: Greater intraoperative blood loss is an independent predictor 4
- Fresh frozen plasma and Vitamin K administration: Independent predictors of hematoma formation 4
Clinical Significance and Complications
Hematoma requiring reoperation dramatically increases the risk of serious complications:
- Deep wound infection: 21.57-fold increased risk 1
- Sepsis: 4.3-fold increased risk 1
- Pneumonia: 3.69-fold increased risk 1
- Mortality: Hematoma itself is an independent risk factor for increased morbidity and mortality despite adequate treatment 4
Expected Blood Loss Parameters
- Mean intraoperative blood loss: Approximately 400-500 ml in standard cases 5
- Hemoglobin drop: Expected fall of approximately 2.5 g/dL perioperatively due to hemorrhage and hemodilution 3
- Mean hemoglobin drop in 48 hours: 3.25 g/dL 5
Preventive Considerations
Preoperative Assessment
- Preoperative anemia: Occurs in approximately 40% of hip fracture patients 3
- Transfusion planning: If hemoglobin is 10-12 g/dL, two units should be crossmatched; if within normal limits, a grouped sample is sufficient 3
- Revision surgery: Incurs greater blood loss and requires preoperative crossmatching according to local guidelines 3
Intraoperative Strategies
- Cell salvage: Should be considered for revision procedures or periprosthetic fractures 3
- Antifibrinolytic medications: Non-use increases bleeding risk 3-fold in high-risk patients 2
- Regional anesthesia: May reduce DVT risk and is preferred when feasible 3
Common Pitfalls
- Underestimating bleeding risk in obese patients: BMI ≥35 nearly doubles hematoma risk 1
- Inadequate monitoring of high-risk patients: Those with bleeding disorders, prolonged operative times, or multiple risk factors require closer postoperative surveillance 1
- Failure to recognize infection risk: Given the 21-fold increased risk of deep wound infection following hematoma evacuation, at-risk patients need enhanced infection monitoring 1