[Blindness after nitrous oxide anesthesia and internal gas tamponade]

The authors describe the case of a patient with bilateral retinal detachment. Immediately after surgery for the second eye under general anesthesia with nitrous oxide, the patient reported severe visual loss in the first eye successfully treated surgically 2 weeks before, with a residual gas bubble (C3F8) of 50%. In this case, nitrous oxide had rapidly entered the gas bubble and induced a transient expansion of the gas tamponade with a dramatic increase in intraocular pressure. The consequence was a central retinal artery occlusion, which resulted in irreparable ischemic retinal damage and blindness, explaining the severe and sudden visual loss. Nitrous oxide is regularly used but contraindicated if intraocular gas is present, due to its potential threat to visual function. We suggest that patients anesthetized with nitrous oxide carry a card or a bracelet detailing the risks of intraocular gas tamponades combined with nitrous oxide and with travel to high altitudes. This would inform not only patients but also medical personnel caring for these patients.