Oncologic Emergencies Flashcards
In which groups of patients is incidence of hypercalcemia most common in?
- NSC lung cancer
- Breast cancer
- Multiple myeloma
- Squamous-cell cancers of the head and neck
- Urothelial carcinomas
- Ovarian cancers
What corrected calcium level defines mild hypercalcemia?
10.5 to 11.9 mg/dL
What corrected calcium level defines moderate hypercalcemia?
12 to 13.9 mg/dL
What corrected calcium level defines severe hypercalcemia?
14+ mg/dL
What other laboratory values should be tested for in hypercalcemia?
- Serum phosphorous
- PTH
- Vitamin D
What is the formula for corrected calcium?
0.8*(4 - albumin) + serum calcium
What are some S/S of hypercalcemia?
- AKI
- N/V
- Lethargy/muscle weakness
- Shortened QT interval
- Arrhythmias
Which etiology accounts for most cases of hypercalcemia?
Humoral (PTH-related peptide increased)
- increased calcium tubular reabsorption and phosphorus excretion
What are the rare causes of hypercalcemia?
- Vitamin D toxicity
- Ectopic PTH production by tumor
What treatment do we use to increase calcium excretion?
NS bolus of 1-2L, followed by 200-500 mL/hr infusion
Furosemide 20-40 mg (fluid overloaded or HF patients)
What treatments do we use to inhibit bone resorption?
- Pamidronate (bisphosphonate)
- Zoledronate (bisphosphonate)
- Denosumab (RANKL-RANK binding inhibitor)
- Calcitonin (direct inhibition and increased Ca2+ excretion)
What dose of pamidronate should we give to a patient with a corrected calcium >12?
90 mg IV
What dose of zoledronic acid should we give to a patient with a corrected calcium >12?
4 mg IV
Should you use bisphosphonates in renal impairment?
NO
How many days do we wait before repeating bisphosphonate doses for hypercalcemia?
7 days
T/F: Denosumab should be avoided in renal impairment
FALSE
Why do we limit calcitonin treatment to 24-48 hours?
Tachyphylaxis
What possible reserved options do we have if main therapies fail for hypercalcemia?
- Steroids
- Cinacalcet
- Dialysis
What labs are characteristic of tumor lysis syndrome?
↑ K
↑ Uric acid
↑ Phosphate
↓ Calcium
What are risk factors for TLS?
- High uric acid at baseline
- Nephropathy
- Hypotension
- HF
T/F: Low WBC leads to a higher risk of TLS
FALSE: High WBC is associated with TLS risk
What is the treatment approach to TLS?
- Monitor labs q4-6 hours
- NS 150-300 mL/hr (NOT SODIUM BICARB)
- Allopurinol / Rasburicase
Which uric acid treatment comes first in high risk TLS patients?
Rasburicase
Which uric acid treatment comes first in intermediate risk TLS patients?
Allopurinol
