[SaO₂ and PaO₂ mismatch: Do not forget hemoglobinopathy]

Area of Science:

• Pulmonary Medicine
• Hematology

Background:

• Clinico-biological parameters like oxygen saturation (SpO2, SaO2) and partial pressure (PaO2) assess oxygen availability.
• Pulse oximetry (SpO2), arterial oxygen saturation (SaO2), and arterial oxygen partial pressure (PaO2) are standard measures.

Observation:

• A patient presented with respiratory failure and chronic dyspnea.
• Decreased SpO2 and SaO2 were noted, contrasting with a normal PaO2.

Findings:

• The observed mismatch between oxygen saturation and PaO2 indicated a hemoglobinopathy.
• The patient was diagnosed with Bassett hemoglobinopathy.

Implications:

• Hemoglobinopathy should be suspected in cases of oxygen desaturation with normal respiratory and cardiac findings.
• Long-term oxygen therapy is not indicated for patients with this type of hemoglobinopathy.