Hypercalcemia and Cancer - Dr. Goldonowicz

Hypercalcemia
- Hypercalcemia relatively uncommon in the ED, but highly correlated with cancer and poor prognosis
     - 25% of cancer patients  
     - 50% die within a month of hypercalcemia dx

- Severe levels can be life threatening
     - Renal failure
     - Dysrhythmias
     - Coma
     - Death

- Occurs due to increased bone resorption and release of calcium
     - Bony mets release cytokines that break down bone
     - Tumors secrete PTHrP and an active form of Vitamin D, causing bone breakdown

- Who to suspect:
    - Elderly
    - Acute confusion/MS change
    - Unexplained weakness
    - History of cancer -- especially breast, lung, lymphoma, or multiple myeloma

- What to look for:
     - Neuropsych, GI and MSK  à vague symptoms

- Evaluate with serum calcium (must account for serum albumin and correct) or ionized calcium
     - Consider the clinical context and order additional labs/tests as necessary, including EKG and CXR

Treatment

Mild

• <12mg/dL with no clinical findings (1.4-2mmol/L ionized)
• Dispo home with close PCP/Oncology f/u
• Stop any calcium supplements or calcium-sparing meds
• Increase weight bearing activity and PO hydration
  

Moderate

• 12-13.5mg/dL (2-2.5mmol/L ionized)
• IVF with NS 200-300mL/hr until euvolemic à then keep UOP 100-150cc/hr
• Loop diuretics only after volume repletion in pts with CHF or CKD
• Touch base with Oncology; consider inpatient admission based on presentation
  

Severe

• >13.5 with symptoms (2.5-3mmol/L ionized)
• IVF as above
• Calcitonin – 4IU/kg subQ or IM 
• Bisphosphonates 

                   - Zoledronic acid – 4mg over 15 min
                   - Pamidronate – 60-90 mg over 2-24 hrs

• Inpatient admission and call Oncology
• Call Nephrology for emergent hemodialysis if:

                    - >13.5 with neuro sxs
                    - >18mg/dL
                    - Renal failure
                    - CHF

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