Oncology IV Flashcards
1
Q
Other Haematological Toxicity or the secret of the full blood count (FBC)
A
- Monitor prior to each cycle of chemotherapy to ensure that bone marrow has recovered
- Minimum requirements
- Neutrophils >1x109/L (Often 1.5)
- Platelets >100x109/L
- Haemoglobin >90g/L
- Limits may be lower for treatment of some haematological malignancies
2
Q
FBC Support
A
- Neutrophils: GCSF support
- GCSF stimulates production of neutrophils
- Primary prophylaxis- when the risk of neutropenia is >20% (particularly for curative cancers)
- Secondary prophylaxis- following the previous episode of neutropenic complications
- Therapeutic use- during the neutropenic episode; reduces infection-related morbidity and mortality
- As adjunct to progenitor cell transplantation
- Used in patients with acute leukaemia and myelodysplasic syndrome
3
Q
FBC support
A
- Platelets
- Platelet infusions if <10x109/L and/or active bleeding
- Review medicines- avoid antiplatelets, anticoagulants, NSAIDs
- Haemoglobin
- Blood transfusions
- Erythropoietin (limited use)
4
Q
Renal function
A
- Monitor U&Es prior to each cycle of chemotherapy
- Important to calculate CrCl prior each cycle of all nephrotoxic drugs and drugs that are excreted primarily via the kidneys: Cisplatin, ifosfamide, high-dose MTX, High-dose cyclophosphamide, Melphalan
- Use Cockcroft-Gault equation to estimate CrCl- <50ml/min signifies impaired renal function
5
Q
Renal function- Hydration
A
- IV hydration is mandatory for cisplatin administration
- Dilutes the drug as it’s excreted via the kidneys to minimise renal toxicity
- Maintain urine output >100mL/hour
- Pre-hydration: 1L saline 0.9% IV, mannitol IV
- Post-hydration: 2L saline 0.9% IV (Or 1L and patient to drink further fluid following administration)
- Hydration is also important during the administration of high-dose MTX, ifosfamide and high-dose melphalan
6
Q
Electrolyte or biochemical disturbance- General
A
- Biochemical disturbances can cause
- Nausea
- Diarrhoea
- Muscle weakness
- Tetany
- Seizures
- Arrhythmias
- Renal failure
- Sudden death
7
Q
Electrolyte- sodium
A
- Hyponatraemia is a low level of sodium in the blood. The adult value for sodium is 136-145 mEq/L
- Drugs- such as diuretics, heparin, certain chemotherapy drugs aminoglutethimide, cyclophosphamide and vincristine
- Conditions related to steroid, hormone or defects in metabolism such: syndrome of inappropriate anti-diuretic hormone (SIADH)- This occurs when a hormone, ADH, is not being properly regulated
8
Q
Electrolyte sodium
Treatment
A
- Treat underlying cause- chemotherapy
- Fluid restriction
- Demeclocycline- especially if caused by SIADH
- Vasopressin receptor antagonist- Tolvaptan
9
Q
Electrolyte- potassium
A
- Cisplatin causes wasting of electrolytes
- Potassium
- Normal range 3.5-5.3 mmol/L
- Include in hydration fluids for cisplatin administration
- Reduced levels may also be associated with severe vomiting and amphotericin therapy
- Hypokalaemia
- K<3.5 mmol/L
- Neuromuscular, cardiovascular and renal effects
10
Q
Potassium treatments
A
- Oral replacement
- Soluble preparations preferable
- Sando-K 2 tabs PO TDS (72 mmol/day)
- IV replacement
- If oral route not suitable
- 10-20 mmol/L saline 0.9% (40-80 mmol/day)
- Pre-filled bags (consult local K guidelines)
- During replacement monitor serum K daily
11
Q
Electrolyte- Magnesium
A
- Normal range 0.7-1.0 mmol/L
- Include in hydration fluids for cisplatin administration
- Reduced levels may be associated with severe vomiting
- Hypomagnesaemia
- Mild: 0.5-0.7 mmol/L; Moderate <0.5 mmol/L
- Signs and symptoms are non-specific, more common in moderate hypomagnesaemia (Musculoskeletal, CNS, CV)
- Linked to other biochemical disturbances (particularly K)
12
Q
Treatment of hypomagnesaemia
A
- Mild
- Oral replacement
- Mg glycerophosphate 4-8mmol PO TDS-QDS (dose limited by side effects)
- Moderate
- IV replacement 16-24mmol/1L saline 0.9% over 12 hours x5days
- During replacement monitor serum Mg daily
- 50% of the dose is renally excreted therefore prolonged treatment needed (5 days)
13
Q
Electrolyte- Calcium
A
- Most common life-threatening metabolic complication of malignancy
- Corrected calcium >2.6mmol/L
- Occurs in ~10% of patients with advanced solid tumours
- Particularly associated with lung, breast, prostate cancer and myeloma
- Ultimate prognosis is poor
14
Q
Hypercalcaemia investigations
A
- Corrected calcium level
- Electrolyte levels: Na, K, Mg- reduced levels seen in hypercalcaemia as Ca is a potent diuretic
- Urea and creatinine- to assess degree of dehydration and also estimate CrCl
- ECG- as risk of arrhythmias
- Bone scan- cause
15
Q
Hypercalcaemia presentation
A
- Inc Ca, Dec Na, Dec K, Dec Mg, Inc urea and creatinine, Dec CrCl
- Renal- Polyuria, polydipsia, dehydration, renal calculi (stones)
- GI- Ab pain, constipation, N&V
- Neurological- Lethargy, fatigue, confusion, irritability, depression, muscle weakness, malaise, come (end-stage)
- Cardiac- Heart block, asystole, arrhythmias, cardiac arrest
