calcium disodium edetate


edetate calcium disodium

(ee-de-tate kal-see-um dye-soe-dee-um) edetate-calcium-disodium,

Calcium Disodium Versenate

(trade name),

calcium EDTA

(trade name),

calcium disodium edetate

(trade name)

Classification

Therapeutic: antidotes
Pharmacologic: chelating agents
Pregnancy Category: B

Indications

Management of acute and chronic lead poisoning, including encephalopathy and nephropathy.

Action

Removes toxic amounts of lead or other divalent or trivalent cations by their displacement of calcium in edetate calcium disodium. Result is a soluble complex that is excreted by the kidneys.

Therapeutic effects

Removal of toxic amounts of lead from the blood and other tissues.

Pharmacokinetics

Absorption: Well absorbed following IM administration.Distribution: Distributed to extracellular fluid. Does not cross the blood-brain barrier.Metabolism and Excretion: Rapidly excreted by the kidneys as unchanged drug or lead complex.Half-life: 20–60 min.

Time/action profile (urinary lead excretion)

ROUTEONSETPEAKDURATION
IMunknownunknownunknown
IV1 hr24–48 hrunknown

Contraindications/Precautions

Contraindicated in: Anuria; Active hepatitis.Use Cautiously in: Underlying renal disease (dose reduction required if serum creatinine >2 mg/dL); Cardiac arrhythmias; Obstetric / Lactation: Pregnancy or lactation (safety not established); Lead encephalopathy (should be used with concurrent dimercaprol); Geriatric: Geriatric patients (dose reduction may be necessary because of age-related decrease in renal function).

Adverse Reactions/Side Effects

Central nervous system

  • headache

Ear, Eye, Nose, Throat

  • lacrimation
  • nasal congestion
  • sneezing

Cardiovascular

  • arrhythmia
  • ECG changes (inverted T waves)
  • hypotension

Gastrointestinal

  • anorexia
  • nausea
  • vomiting

Genitourinary

  • nephrotoxicity (most frequent)
  • glycosuria
  • proteinuria

Fluid and Electrolyte

  • hypercalcemia
  • zinc deficiency

Hematologic

  • anemia

Local

  • pain at IM site
  • phlebitis at IV site

Musculoskeletal

  • arthralgia
  • myalgia

Neurologic

  • numbness
  • tingling
  • tremor

Miscellaneous

  • chills
  • excessive thirst
  • fever

Interactions

Drug-Drug interaction

↓ duration of action of zinc insulin preparations.

Route/Dosage

Various other regimens are usedIntramuscular Intravenous (Adults and Children) 1000 mg/m2/day for 5 days (not to exceed 2 g/day). May be repeated after 2–4 day rest period. May be given as an infusion over 8–12 hr or in divided doses IM every 8–12 hr.

Renal Impairment

Intramuscular Intravenous (Adults) The following regimens may be repeated at monthly intervals until lead excretion is reduced toward normal.Serum creatinine 2–3 mg/dL—500 mg/m2/day for 5 days.Serum creatinine 3–4 mg/dL-500 mg/m2 every 48 hr for 3 doses.Serum creatinine > 4 mg/dL-500 mg/m2/week.

Availability

Injection: 200 mg/mL

Nursing implications

Nursing assessment

  • Assess patient and family members for evidence of lead poisoning prior to and periodically throughout therapy. Acute lead poisoning is characterized by a metallic taste, colicky abdominal pain, vomiting, diarrhea, oliguria, and coma. Symptoms of chronic poisoning vary with severity and include anorexia, a blue-black line along the gums, intermittent vomiting, paresthesia, encephalopathy, seizures, and coma.
  • Monitor intake and output and daily weight. Report discrepancies. If patient is anuric, edetate calcium disodium should be held until urine flow is established by IV hydration.
  • Monitor neurologic status closely (level of consciousness, pupil response, movement). Notify health care professional immediately of any changes. Infuse slowly; rapid infusion rate may increase intracranial pressure. Restricting fluids may decrease risk of increased intracranial pressure.
  • Monitor vital signs and ECG frequently. Notify health care professional of hypotension or T-wave inversion or of fever, chills, malaise, or nasal congestion. This histamine-like response usually resolves in 48 hr.
  • Lab Test Considerations: Monitor serum and urine lead levels prior to and periodically during therapy. Wait at least 1 hr after infusing edetate calcium disodium before drawing serum lead level.
    • Monitor urinalysis daily and serum creatinine, BUN, alkaline phosphatase, calcium, and phosphorus levels and hepatocellular enzymes. Both lead and edetate calcium disodium are nephrotoxic. Notify health care professional if hematuria, proteinuria, or large renal epithelial cells are present.
    • May cause an increase in urine glucose.

Potential Nursing Diagnoses

Risk for poisoning (Indications, Patient/Family Teaching)
Impaired home maintenance (Indications)
Deficient knowledge, related to medication regimen (Patient/Family Teaching)

Implementation

  • Do not confuse with edetate disodium.
    • Administer IM or IV; oral administration may increase absorption of lead.
    • Patients with serum lead levels of 70 mcg/dL or more or those with lead encephalopathy should also be treated with dimercaprol (BAL). Administer these medications at separate sites.
  • Intramuscular: IM is the preferred route for children and patients with lead encephalopathy. Lidocaine or procaine 1% should be added to minimize pain at injection site (1 mL procaine or lidocaine to 1 mL edetate calcium disodium ratio, for a final concentration of 0.5% procaine or lidocaine). Administer deep IM into well-developed muscle; massage well. Rotate sites.
  • Intravenous Administration
  • Continuous Infusion: Diluent: Dilute in 250–500 mL D5W or 0.9% NaCl. Administer daily dose over 8–12 hr.
  • Y-Site Compatibility: epinephrine
  • Additive Incompatibility: D10W, LR

Patient/Family Teaching

  • Home Care Issues: Discuss need for follow-up appointments to monitor lead levels. Additional treatments may be necessary.
    • Consult public health department regarding potential sources of lead poisoning in the home, workplace, and recreational areas.

Evaluation/Desired Outcomes

  • Decrease in symptoms of lead poisoning.
    • Decrease in serum lead levels to below 20 mcg/dL, although the normal upper limit is 10 mcg/dL.

calcium disodium edetate

A substance used to bind metallic ions, such as lead or zinc. It is used to treat poisoning caused by those metals. See also: calcium