|Non invasive ventilation (NIV)
Ineffective for those with large volume of distribution Amiodarone and paraquat or those heavily protein bound - Digoxin and phenytoin
- Works on the basis of the diffusion of blood against a dialysate across a semipermeable membrane. The blood enters thousands of small semipermeable microtubules with dialysate fluid running in the opposite direction. Dialysate contains high bicarbonate to correct acidosis, low potassium and low calcium.
- High blood flow (200 ml/min) is needed so a surgically constructed AV fistula where there is a connection between arterial and venous blood is placed usually in the forearm. It usually feels like a cat purring under the skin. The endothelium of the venous side of the shunt becomes thickened and arterialised over 6 weeks and so can be used with the large needs required for dialysis
- The patient is prepared for dialysis at CKD stage 4 allowing time for fistula development.
- Where there is no fistula then central venous access with a double lumen catheter either in the internal jugular or subclavian and lastly femoral vein
- Haemodialysis can be carried out usually for 4-5 hours 3 times a week. Heparin is needed to ensure that clotting does not occur as the blood circulates through the haemodialysis
- Hypotension is one of the commonest complications due to volume loss in the process. Patient weight is a guide. Remember also that dialysed patients are basically immunosuppressed and infections need treatment early. Creatinine and urea improve but not back to normal levels
- Alcohol, Barbiturates
- Ethylene Glycol, Lithium
- Methanol, Salicylate, Theophylline
- Fluid overload, Hypotension, Atherosclerosis, Sepsis
- Carpal tunnel syndrome (Beta2 microglobulin) not removed by haemodialysis and builds up over months and years