Name of the Procedure:

Glucagon Tolerance Panel (for Insulinoma)

Summary

The Glucagon Tolerance Panel is a diagnostic test used to measure glucose and insulin levels in the blood. It helps identify the presence of insulinoma, a type of tumor in the pancreas that causes excessive insulin production.

Purpose

This procedure is designed to diagnose insulinoma by assessing how the pancreas responds to glucagon, a hormone that raises blood glucose levels. The goal is to detect abnormal insulin levels in response to glucagon administration, which may indicate the presence of an insulinoma.

Indications

• Unexplained hypoglycemia (low blood sugar levels).
• Symptoms such as sweating, confusion, tremors, and fainting.
• Patients with suspected insulinoma based on clinical evaluation and preliminary tests.

Preparation

• Patients may need to fast for at least 8 hours before the test.
• Certain medications that affect glucose or insulin levels should be temporarily discontinued, as directed by the healthcare provider.
• Baseline blood tests may be performed to assess overall health and rule out other conditions.

Procedure Description

1. A baseline blood sample is taken to measure glucose and insulin levels.
2. Glucagon is administered by injection.
3. Blood samples are then collected at 30, 60, and 90 minutes after glucagon administration to measure glucose (82947 x 3) and insulin (83525 x 3) levels.
4. The samples are analyzed in a laboratory to determine how the glucose and insulin levels respond to glucagon.

Duration

The entire procedure typically takes around 2 hours, including the waiting periods between blood samples.

Setting

The procedure is usually performed in an outpatient clinic or hospital setting.

Personnel

• A physician, typically an endocrinologist or a specialist in metabolic disorders.
• A nurse or phlebotomist for blood sample collection.
• Laboratory technicians for sample analysis.

Risks and Complications

• Minor risks include discomfort or bruising at the injection or blood draw site.
• Rare risks might include allergic reactions to glucagon or transient hypoglycemia.

Benefits

• Accurate diagnosis of insulinoma, leading to appropriate treatment.
• Insight into abnormal glucose regulation in the body.
• Early detection of potential pancreatic tumors.

Recovery

• Patients can typically resume normal activities immediately after the procedure.
• Follow-up instructions may include monitoring for any delayed reactions or symptoms.
• A follow-up appointment may be scheduled to discuss the test results and next steps.

Alternatives

• Other diagnostic tests such as a 72-hour fasting test or imaging studies (e.g., MRI or CT scan) to locate insulinomas.
• Pros: Alternative tests might be less invasive.
• Cons: Alternatives may be more time-consuming or less definitive without combined biochemical and imaging results.

Patient Experience

• Patients may feel slight discomfort from the needle during blood draws.
• Post-procedure, some may experience mild side effects like nausea or dizziness.
• Pain management is usually not required, and comfort measures include relaxation and hydration during the test.