Ichemic optic neuropathy following pine urgery

Viual lo after monocular urgery i rare, but devatating. The mot common caue of perioperative viual lo (POVL) i ichemic optic neuropathy (ION). Increaing number of cae of ION are being reported after pine urgery, but the etiology of potoperative ION remain poorly undertood. The growing concern about POVL ha led neuroanetheiologit to etablih the AA Potoperative Viual Lo Regitry. Thi article ummarized our current knowledge on thi topic. The author reviewed the literature and elected cae report of ION, pecifically thoe reported after pine urgery performed with the patient in the prone poition. Mot of the cae involved poterior ION (PION, n = 17), and the remainder anterior (AION, n = 5). Mot patient had no or few preoperative vacular dieae rik factor. All except one PION and 2 of 5 AION cae reported ymptom onet within the firt 24 hour after urgery. Viual lo wa frequently bilateral (40% of AION, 47% of PION cae). Mean operative time exceeded 450 minute. The lowet average intraoperative mean arterial blood preure wa 64 mm Hg and the mean lowet intraoperative hematocrit wa 27%. The average blood lo wa 1.7 L for AION and 5 L for PION patient. PION patient received an average of 8 L of crytalloid olution and 2.2 L of colloid intraoperatively. Thi compilation of cae report ugget that a combination of prolonged urgery in the prone poition, decreaed ocular perfuion preure, blood lo and anemia/hemodilution, and infuion of large quantitie of intravenou fluid are ome of the potential factor involved in the etiology of potoperative ION. However, level of blood preure and anemia intraoperatively were frequently at level conidered acceptable in anetheia practice. The etiology of potoperative ION remain incompletely undertood. Potential trategie to avoid thi complication are dicued. —Valérie Bioue