Name of the Procedure:

Carboxyhemoglobin; Qualitative Common name(s): COHb test

Summary

A Carboxyhemoglobin test detects the level of carbon monoxide (CO) bound to hemoglobin in the blood. This test indicates whether someone has been exposed to CO, which is a dangerous gas.

Purpose

The test diagnoses carbon monoxide poisoning by measuring the percentage of carboxyhemoglobin in the blood. The goals of the procedure are to confirm exposure to CO, assess the severity of poisoning, and guide appropriate treatment.

Indications

• Symptoms warranting the test include headache, dizziness, weakness, nausea, vomiting, chest pain, and confusion.
• Situations such as exposure to fires, faulty heating systems, or prolonged time in enclosed spaces with combustible engines make the procedure appropriate.

Preparation

• No major preparation is typically required.
• Patients may need to report any recent exposure to CO sources.
• Standard blood draw precautions are followed.

Procedure Description

1. A healthcare professional uses a needle to draw a blood sample from a vein.
2. The sample is placed in a vial and sent to a laboratory.
3. The lab uses spectrophotometry or gas chromatography to analyze the hemoglobin in your blood.

Duration

The blood draw itself takes about 5 to 10 minutes. Lab analysis time varies, but results can often be available within a few hours to a day.

Setting

The procedure is performed in a hospital, clinic, or laboratory.

Personnel

• Phlebotomist or nurse to draw the blood sample.
• Laboratory technicians or pathologists to analyze the sample.

Risks and Complications

• Common risks include minor pain or bruising at the puncture site.
• Rare risks include infection or hematoma formation.
• Complications from the test itself are minimal; the main risk is related to undiagnosed CO exposure.

Benefits

• Quick and accurate diagnosis of carbon monoxide poisoning.
• Prompt diagnosis enables rapid treatment, which can be life-saving.
• Results help tailor further medical interventions.

Recovery

• No specific post-procedure care required.
• Discomfort at the puncture site resolves within a few hours.
• Follow-up treatments depend on the test results.

Alternatives

• Pulse CO-oximetry, a non-invasive alternative, provides an immediate reading but may be less accurate.
• Monitoring environmental CO levels when exposure is suspected but blood testing offers definitive diagnosis.

Patient Experience

• Slight discomfort during blood draw.
• Minimal to no pain afterward.
• Quick return to usual activities post blood draw, except if CO poisoning is confirmed, which necessitates immediate further treatment.