DESCRIPTION

Arsine (AsH₃) is a colorless, nonirritating, inflammable gas with a garlicky odor.

FORMS AND USES

• Exposure to arsine usually occurs in the industrial/occupational setting when arsenic-containing products are exposed to strong acids or heated.
• Arsine may be produced during smelting and refining of metals and ores, galvanizing, soldering, etching, lead plating, metallurgy, burning fossil fuels, and the microelectronic/semiconductor industry (computer chips made of gallium arsenide are etched with strong acids).

TOXIC DOSE

Immediate death has occurred at 150 ppm.

PATHOPHYSIOLOGY

• Arsine rapidly enters red blood cells, depletes glutathione and produces rapid and severe Coombs' negative hemolytic anemia.
• Death may occur before the classic signs and symptoms of arsine poisoning develop.

EPIDEMIOLOGY

Poisoning is rare, but may be fatal.

CAUSES

Exposure usually occurs in the industrial/occupational setting.

RISK FACTORS

Exposure may go unnoticed because the odor is not noticeable during industrial use, and toxicity may develop with exposure below the odor threshold.

WORKPLACE STANDARDS

• ACGIH. TLV TWA is 0.05 ppm
• OSHA. PEL TWA is 0.05 ppm
• NIOSH. IDLH is 3 ppm

Section Outline:

• DESCRIPTION
• FORMS AND USES
• TOXIC DOSE
• PATHOPHYSIOLOGY
• EPIDEMIOLOGY
• CAUSES
• RISK FACTORS
• WORKPLACE STANDARDS

SIGNS AND SYMPTOMS

• In cases where toxicity develops, there is usually a delay of 2 to 24 hours before toxicity becomes apparent.
• As hemolysis develops, symptoms of headache, weakness, chills, thirst, and abdominal pain develop.
• The triad of abdominal pain, hematuria, and bronze tint skin are characteristic of serious arsine poisoning.

HEENT

A garlic odor may be noticeable on the breath.

Dermatologic

Reddish staining of the conjunctiva and duskily bronzed skin (due to the presence of hemoglobin, not bilirubin) may develop within 12 to 36 hours.

Cardiovascular

• ECG changes include high-peaked T waves; T-wave changes are most pronounced 2 to 12 days after exposure.
• Ventricular dysrhythmia may develop.

Gastrointestinal

Nausea, vomiting, diarrhea, and abdominal pain.

Hematologic

Severe hemolysis may develop.

Urinary

• Dark red discoloration of the urine, hemoglobinuria, or hematuria frequently appears 4 to 12 hours after inhalation.
• Hemoglobinuria can cause acute tubular neurosis and renal failure.

PROCEDURES AND LABORATORY TESTS

Essential Tests

• Complete blood count with peripheral smear and serum haptoglobin should be obtained serially to evaluate for hemolysis.
• Serum electrolytes, BUN, and creatinine should be followed serially in symptomatic patients to assess toxicity.

Recommended Tests

• Blood and urine arsenic levels should be ascertained. Normal values are less than 20 µg/dl for blood, less than 50 µg/l in urine for occupational exposure.
• ECG to evaluate cardiac rhythym.

Section Outline:

• SIGNS AND SYMPTOMS
  • HEENT
  • Dermatologic
  • Cardiovascular
  • Gastrointestinal
  • Hematologic
  • Urinary
• PROCEDURES AND LABORATORY TESTS
  • Essential Tests
  • Recommended Tests

• Treatment should focus on frequent monitoring of serum electrolytes and renal function, packed red blood cell transfusion, and aggressive supportive care to reduce further renal insult.
• Dose and time of exposure should be determined for all substances involved.

DIRECTING PATIENT COURSE

The health-care professional should call the poison control center when:

• Arsine exposure is suspected.
• Coingestant, drug interaction, or underlying disease presents an unusual problem.

The patient should be referred to a health-care facility when:

• History of arsine exposure is obtained.
• Coingestant, drug interaction, or underlying disease presents an unusual problem.

Admission Considerations

Inpatient management in an ICU is warranted for all patients with possible arsine poisoning.

DECONTAMINATION

Patient must be removed from the exposure and 100% oxygen should be administered.

ANTIDOTES

• There is no specific antidote for arsine poisoning.
• The use of British anti-Lewisite (BAL) in the treatment of acute arsine poisoning has been disappointing; it does not appear to prevent or reduce hemolysis.

ADJUNCTIVE TREATMENT

• Exchange transfusion has been advocated as the most efficient and effective management for acute, severe arsine poisoning.
• Intravenous fluids should be administered to the patient so that good urine output (1-2 ml/kg/h) is maintained.
• Exchange transfusion and hemodialysis may be required when renal insufficiency or failure develop.
• Diuretics, mannitol, and urinary alkalinization have been advocated, but supporting data are lacking.

Section Outline:

• DIRECTING PATIENT COURSE
  • Admission Considerations
• DECONTAMINATION
• ANTIDOTES
• ADJUNCTIVE TREATMENT

EXPECTED COURSE AND PROGNOSIS

• Large exposures can cause death rapidly.
• Patients suffering from serious exposure often sustain multiple-organ injury.

DISCHARGE CRITERIA/INSTRUCTIONS

• Patients who are asymptomatic and hemodynamically stable for at least 24 hours after admission and show no evidence of hemolysis or worsening renal function may be discharged.
• Serum electrolytes, BUN, creatinine, and complete blood count should be repeated 1 to 2 days after discharge in patients who suffered toxic effects.

Section Outline:

• EXPECTED COURSE AND PROGNOSIS
• DISCHARGE CRITERIA/INSTRUCTIONS

DIAGNOSIS

Arsine poisoning may require 2 to 24 hours to develop symptoms.

TREATMENT

Failure to admit exposed patients to the ICU may allow injury to progress.

FOLLOW-UP

Premature discharge of the patient from the hospital can occur before onset of symptoms.

Section Outline:

• DIAGNOSIS
• TREATMENT
• FOLLOW-UP

Toxic effect of other gases, fumes, or vapors.

RECOMMENDED READING

Poisindex editorial staff: Arsine. In Rumack B, Reder PK, Gelman CR (eds.) Micromedex, Englewood Colorado (Edition expires August 31, 1998).

Author: Luke Yip

Reviewer: Kennon Heard