Indications for haemoperfusion

In short, its for substances which cannot be cleared by dialysis owing to the large volume of distribution. A summary of haemoperfusion targeted more at the time-poor CICM exam trainee is available in the Required Reading section for renal SAQs in the Part 2 exam.

Drugs susceptible to removal by haemoperfusion

Harbord et al. have a chapter on drug removal by extracorporeal techniques. That chapter within it contains several massive tables, listing all the possible and impossible drugs which can be removed by an extracorporeal circuit. The haemoperfusion-specific information resides in Table 174-2 on page 922.

The list is massive, and impossible to memorise. Instead, it is easier to remember basic features which discriminate between those drugs that are easily removed by dialysis and those that are easily removed by haemoperfusion.

Non-toxicological indications for haemoperfusion

• Lipopolysaccharide endotoxin: The cell wall component of gram-negative bacteria, which is responsible for much of the nastiness you see in septic shock
  • The sorbent for this tends to be a polymyxin-impregnated polystyrene fiber

• Superantigen: The secreted exotoxin of gram-positive bacteria, which directly activates T cells by binding to the MHC class II molecules.

• Various cytokines: Both proinflammatory and antiinflammatory ones are cleared by hemoperfusion

• Hepatic failure: accumulated toxins can be susceptible to haemoperfusion

• End stage renal failure with aluminium intoxication: where it is used along with a chelating agent

Broad generalization:

• Hemoperfusion should only be used in situations where
•  There is severe life-threatening intoxication with substances which are not going to be well removed by the liver or kidneys.
• There is an impairment of liver and kidneys, preventing clearance.

If a toxin is equally well cleared by hemodialysis and hemoperfusion, then hemodialysis is preferred, because it will also correct any underlying acid-base disturbance

Specific Indications

• End stage renal failure with aluminium intoxication where it is used along with a chelating agent

• Liver Failure: as bridging therapy, to remove the toxins that would otherwise cause coma, when waiting for a transplant. This indication is debated

Specific Toxicities

- The following drugs are well cleared (at least in animal models):

• Suicide favourites

  • Paracetamol
  • Barbiturates
  • Aspirin
  • Tricyclics
  • Phencyclidine (PCP)
  • Theophylline
  • Phalloidin (from Amanita Phalloides, the death cap mushroom)

• Elemental metals

  • Iron

  • Thallium

  • Aluminium

• Chemotherapy agents

  • Doxorubicin
  • Cisplatin
  • Methotrexate

• Antibiotics

  • Vancomycin

  • Gentamycin

  • Ampicillin

  • Clindamycin

  • Isoniazid

• Accidental industrial toxins

  • Paraquat

  • Diquat

  • Parathion

  • Methylparathion

  • Organophosphates

  • Trichloroethane

  • Ethylene oxide

  • Carbon tetrachloride

• Accidental hospital toxins

  • Digoxin
  • Diltiazem
  • Metoprolol
  • Promethazine
  • Chlorpromazine
  • Valproate
  • Tramadol
  • Colchicine  

Removal of specific substances of interest

• Lipopolysaccharide endotoxin: The cell wall component of gram-negative bacteria, which is responsible for much of the nastiness you see in septic shock
• Superantigen:The secreted exotoxin of gram-positive bacteria, which directly activates T cells by binding to the MHC class II molecules.
• Various cytokines: Both proinflammatory and antiinflammatory ones are cleared by hemoperfusion