Lead Acetate

CAS RN: 301-04-2

Treatment Overview

0.4.2 ORAL EXPOSURE
  • A) MANAGEMENT OF MILD TO MODERATE TOXICITY
    • 1) The most important treatment is to identify the source of lead exposure (generally requires an environmental evaluation of the home, an occupational history of patient and/or family members, and evaluation of hobbies) and removal from further exposure. Chelation therapy is recommended for levels of 45 mcg/dL or more in children. Adults with symptoms or blood lead concentrations above 50 mcg/dL, should also be chelated. Levels that high also merit follow-up blood lead testing, a lab screening for anemia, and possibly radiographs to look for lead in the GI tract. Outpatient chelation can be achieved with oral succimer. D-Penicillamine is another oral agent used for chelation in children, but is considered a second-line agent after succimer.
  • B) MANAGEMENT OF SEVERE TOXICITY
    • 1) In children, a blood lead concentration of 70 mcg/dL or more is an indication for hospitalization. Whole bowel irrigation with polyethylene glycol should be performed if there is evidence of lead in the GI tract on radiograph. Oral chelation (succimer) can be performed in children with blood lead concentrations less than 70 mcg/dL without evidence of encephalopathy. In patients with encephalopathy or in children with blood lead concentrations of 70 mcg/dL or more, parenteral chelation (intramuscular dimercaprol (BAL) should be initiated first, followed by intravenous edetate calcium disodium. Treat seizures with IV benzodiazepines. Seizures from lead encephalopathy may be resistant to anticonvulsant therapy; barbiturate-induced coma and aggressive control of intracranial pressure may be needed. Cerebral edema may be managed by ventilation and the administration of mannitol and/or dexamethasone. Lumbar puncture is be dangerous in the presence of increased intracranial pressure.
  • C) DECONTAMINATION
    • 1) PREHOSPITAL: Activated charcoal may be used after an acute ingestion. For dermal, eye or inhalational exposures, treatment is standard decontamination including removal of contaminated clothing and washing the exposed area with soap and water.
    • 2) HOSPITAL: Activated charcoal may be used after an acute ingestion. There is no evidence to support the use of gastric lavage in lead ingestions. Whole bowel irrigation with polyethylene glycol solution should be considered when there is radiographic evidence of lead foreign bodies in the GI tract.
  • D) AIRWAY MANAGEMENT
    • 1) Airway management is not likely to be directly an issue with lead toxicity unless the patient has encephalopathy. If lead encephalopathy is suspected, the patient should be evaluated and treated for increased intracranial pressure.
  • E) ANTIDOTE
    • 1) Several chelating agents are effective in increasing lead excretion. Parenteral chelators are generally reserved for patients with very high blood lead concentrations (BLL) (70 mcg/dL or more in children), evidence of encephalopathy, or patients who cannot tolerate oral medications. The following guidelines have been recommended:
    • 2) ENCEPHALOPATHY: ADULTS or CHILDREN: BAL: 450 mg/m(2)/day (24 mg/kg/day) (regimen, 75 mg/m(
    • 2) IM every 4 hours) for 5 days. IV edetate calcium disodium should be given immediately after the second dose of BAL. Dose: 1500 mg/m(2)/day (50 mg/kg/day) continuous infusion or 2 to 4 divided IV doses for 5 days.
    • 3) SYMPTOMATIC ADULTS WITH BLL GREATER THAN 100 mcg/dL and CHILDREN WITH BLL GREATER THAN 69 mcg/dL: BAL: 300 to 450 mg/m(2)/day (18 to 24 mg/kg/day) (regimen, 50 to 75 mg/m(
    • 2) every 4 hours for 3 to 5 days). IV edetate calcium disodium should be given immediately after the second dose of BAL. Dose: 1000 to 1500 mg/m(2)/day (50 to 75 mg/kg/day) continuous infusion or 2 to 4 divided IV doses for 5 days.
    • 4) ADULTS WITH MILD SYMPTOMS or BLL 70 to 100 mcg/dL: Succimer 700 to 1050 mg/m(2)/day (regimen, 350 mg/m(
    • 2) (10 mg/kg) orally every 8 hours for 5 days and then every 12 hours for 14 days).
    • 5) ASYMPTOMATIC CHILDREN WITH BLL BETWEEN 45 to 69 mcg/dL: Succimer 700 to 1050 mg/m(2)/day (regimen, 350 mg/m(
    • 2) (10 mg/kg) orally every 8 hours for 5 days, and then every 12 hours for 14 days) OR IV edetate calcium disodium 1000 mg/m(2)/day continuous infusion or 2 to 4 divided IV doses for 5 days OR D-penicillamine 25 to 35 mg/kg/day in divided doses. Treatment is usually initiated at 25% of this dose and gradually increased to the full dose over 2 to 3 weeks to minimize adverse reactions. Do not use D-penicillamine in patients with known penicillin allergy.
    • 6) ASYMPTOMATIC ADULTS and BLL LESS THAN 70 mcg/dL: No routine chelation is indicated.
    • 7) ASYMPTOMATIC CHILDREN and BLL 20 to 44 mcg/dL: No routine chelation is indicated. Succimer (same regimen as above) has been used.
    • 8) NOTE: When the BLL is improving per the guidelines and the patient is able to tolerate oral medications, BAL can be replaced with succimer with no waiting period between treatments. If Monitor blood lead concentrations at the end of chelation and for several weeks to months after the completion of therapy to detect rebound or reexposure, and guide the need for further courses of chelation.
  • F) ENHANCED ELIMINATION
    • 1) Chelators enhance lead excretion. There is no evidence to support the use of any of the following: dialysis, hemoperfusion, urinary alkalinization and multiple dose charcoal.
  • G) PATIENT DISPOSITION
    • 1) HOME CRITERIA: Most asymptomatic lead exposures can be managed on an outpatient basis, as long as further lead exposure can be prevented and patient follow-up can be established.
    • 2) OBSERVATION CRITERIA: Symptomatic lead exposures or patients with a potentially significant oral ingestion (eg, ingestion of a known lead figurine or key chain) merit immediate evaluation at a health care facility. If a significant ingestion can be ruled out (eg, via radiographs), asymptomatic patients may be discharged to home.
    • 3) ADMISSION CRITERIA: Symptomatic patients or patients with a potentially high lead exposure/levels (for children, whole blood lead levels 70 mcg/dL or more) should be admitted. The patient's clinical status should determine whether or not the patient should go to the ward or ICU (eg, encephalopathic patients merit an ICU admission). Criteria for discharge should include improvement/resolution of symptoms, transition to oral chelation, and known removal of lead exposure.
    • 4) CONSULT CRITERIA: Consultation with your local poison center/toxicologist is advised. Public health departments should also be notified to arrange home visit and environmental assessment. Notify OSHA for occupational lead poisoning.
  • H) PITFALLS
    • 1) Diagnosis may be missed without standard lead screenings in infants/toddlers or if a careful history is not obtained. Identification of lead source and its removal is paramount. Diagnosis of lead poisoning may be delayed as the patient may present with pancytopenia and dysplastic changes in bone marrow, mimicking a malignancy.
  • I) TOXICOKINETICS
    • 1) Inorganic lead is absorbed after ingestion (more readily by children than adults) or inhalation. Dermal absorption of inorganic lead is minimal, but skin irritation and increased absorption may occur with organic lead compounds. Lead accumulates in the human body over one's lifetime. The half-life of lead is estimated at 0.4 to 3.6 years. Blood lead is 99% bound to erythrocytes. Over 90% of absorbed lead is incorporated in bone, but lead distributes throughout the body. Excretion occurs primarily via the kidneys (65%) and to a lesser extent bile (35%). Rebound of blood lead concentrations is typical after chelation and is due to redistribution from bone stores.
  • J) PREDISPOSING CONDITIONS
    • 1) Young children are more sensitive to lead's negative effects on neurodevelopment. Patients with pica and iron-deficiency may also be more sensitive to lead's effects.
  • K) DIFFERENTIAL DIAGNOSIS
    • 1) Differential diagnosis includes other causes of abdominal pain, anemia, and encephalopathy, which includes infectious and nutritional etiologies. Diagnosis of lead poisoning may be delayed as the patient may present with pancytopenia and dysplastic changes in bone marrow, mimicking a malignancy.
0.4.3 INHALATION EXPOSURE
  • A) Initial treatment is removal from exposure and fresh air.
0.4.4 EYE EXPOSURE
  • A) Standard eye care decontamination is recommended; remove any foreign bodies.
0.4.5 DERMAL EXPOSURE
  • A) OVERVIEW
    • 1) Initial treatment is removal from exposure and washing with soap and water.
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