Publication:

A parturient with congenital methemoglobinemia: navigating the oxygen saturation gap

Congenital methemoglobinemia (CMH) presents unique anesthetic challenges due to oxidative stress risks. We report a primigravida with type 1 CMH presenting with a profound oxygen saturation gap. Labor analgesia was successfully managed using a continuous epidural infusion of ultra-low dose bupivacaine (0.0625%) and fentanyl. The protocol strictly mandated avoiding oxidizing agents, notably substituting lidocaine with epidural bupivacaine for perineal repair. The patient was hemodynamically stable and delivered a healthy neonate. This case validates ultra-low dose epidural bupivacaine as a safe, effective strategy for labor analgesia in CMH, minimizing systemic drug load and oxidative risks.