Therapeutic Handbook - GGC Prescribing

N.B.• Laboratory TLS = > 2 laboratory changes (as per table on the previous page ) within 3 daysbefore or 7 days after chemotherapy.• Clinical TLS = laboratory TLS plus one or more of the following that is not directly orprobably attributable to a therapeutic agent: increased serum creatinine concentration(> 1.5 x ULN), cardiac arrhythmia / sudden death, or a seizure.Crystallisation of uric acid in renal tubules can further impair renal function. This is an oncologicalemergency and warrants aggressive therapy and possibly renal support. Sudden death may resultfrom hyperkalaemia and cardiac arrest.Treatment of established TLS (only under supervision ofhaemato-oncologist)First page the on-call haematology registrar urgently. Effective management involves the combinationof treating specific electrolyte abnormalities and/or acute renal failure. The haematology registrarwill advise on use of a loop diuretic e.g. furosemide, and intravenous fluids (up to 4 - 6 L/24hours)to attempt to wash out the obstructing uric acid crystals. Rasburicase should also be prescribed.This may only be prescribed by the haematology specialist and is highly effective in causing a rapidreduction in serum urate levels.Renal support with dialysis or continuous veno-venous haemofiltration can be life saving in thesepatients. Seek an early renal opinion in all established cases particularly in those with oliguria,persistent hyperphosphataemia and hyperkalaemia.Management of electrolyte abnormalitiesFor treatment of hyperkalaemia and hypocalcaemia (seek specialist advice), refer to pages 296 and306.Hyperphosphataemia• Phosphate > 2.1 mmol/L (moderate) – Increase hydration. Administer phosphate binder (calciumacetate oral 1 g three times a day, adjust according to phosphate concentration – usualdose 4 - 6 g daily; max 12 g daily)• Phosphate > 2.5 mmol/L (severe) – Urgent renal opinion.Uraemia: early renal opinion in all patientsOncological EmergenciesPage 335