Question 4

College answer

Not available.

Discussion

a) Risk factors for bleeding after kidney biopsy include:

b)

Possible steps to reduce the risk of bleeding include:

• Assess coagulation: ideally, with TEG or ROTEM
• Withhold anticoagulation and antiplatelet agents
• Administer DDAVP to control the uraemia-associated platelet dysfunction
• Control BP during the procedure with a mixture of short-acting antihypertensives and adequate sedation
• Use general anaesthetic or sedation to reduce patient movement during the procedure
• Use ultrasound guidance

c)

Three options are surgery, endovascular repair/embolisation, or conservative management.

• Endovascular repair/embolisation:
  • Advantages:
    • Minimally invasive: can be tolerated by a reasonably awake patient, which means no need for a general anaesthetic
    • Stents and suchlike can be deployed via an endovascular approach, i.e. embolisation is not the only possible solution
    • Less blood loss than with an open approach
  • Disadvantages:
    • This bleeding needs to be arterial, or you will get nowhere.
    • There needs to be a significant rate of bleeding for it to be detectable as an extravasation of contrast
    • You do often end up embolising various useful structures (eg. kidney).
    • The bleeding may continue without your knowledge, i.e. it may not be immediately apparent from imaging
    • Interventional radiology services may not be available everywhere
    • Radiation and contrast exposure are necessary
• Surgical control
  • Advantages:
    • Haemostasis is easier to confirm by direct vision
    • Repair of damaged vessels is possible, preserving the function of the kidney
    • Contrast is not required
    • Venous bleeding can be controlled in this manner
    • Allows the abdomen to be left open, preventing abdominal compartment syndrome
  • Disadvantages:
    • Highly invasive procedure, with nontrivial associated pain and potentially long recovery time
    • Requires a general anaesthetic
    • Requires trained surgical staff, i.e. also not available everywhere
    • More blood loss than IR procedure
• Conservative management
  • Advantages:
    • No invasive procedures, no radiation or contrast, no complications of anaesthetic
    • Haematoma may tamponade itself and the bleeding will eventually stop
    • If the haematoma is caused by coagulopathy and antiplatelet effects, the bleeding should stop once these are corrected
    • No embolisation or ligation means no loss of organ perfusion and function 
  • Disadvantages:
    • This is the option with the highest transfusion and blood product requirement
    • Transfusion is itself not without risk
    • Tense haematoma may put pressure on surrounding structures, and the kidney may lose blood supply anyway
    • Abdominal compartment syndrome may develop
    • In a proportion of cases, this management strategy will fail, and open surgery or IR procedures will become necessary.