Severe decrease in SpO₂ and methemoglobinemia following subareolar isosulfan blue administration and clinical...

Area of Science:

• Oncology
• Surgical Pathology
• Anesthesiology

Background:

• Axillary lymph node status is crucial for breast cancer prognosis and adjuvant therapy decisions.
• Sentinel lymph node biopsy (SLNB) is a standard minimally invasive technique for axillary staging.
• Isosulfan blue dye is commonly used in SLNB with a low complication rate.

Purpose of the Study:

• To report a rare case of severe methemoglobinemia following isosulfan blue administration during SLNB.
• To highlight the potential for serious complications despite the dye's generally safe profile.

Main Methods:

• A case report of a 67-year-old female patient undergoing SLNB under general anesthesia.
• Administration of isosulfan blue dye for sentinel lymph node identification.
• Monitoring for adverse events, including SpO2 levels and clinical signs.

Main Results:

• The patient developed severe hypoxemia (decreased SpO2) due to methemoglobinemia post-isosulfan blue administration.
• Clinical signs included skin and urine discoloration, inconsistent with the patient's overall clinical picture.
• This represents a rare but significant adverse event associated with isosulfan blue.

Conclusions:

• Methemoglobinemia is a rare but serious potential complication of isosulfan blue dye used in SLNB.
• Clinicians should be vigilant for this adverse event, even with routine dye usage.
• Prompt recognition and management are essential for patient safety in breast cancer surgery.