Perioperative optic neuropathy in patients undergoing off‑pump coronary artery bypass graft surgery.

ABSTRACT

Aims and Objectives: Perioperative optic neuropathy (PON) is a rare, but devastating complication following coronary artery bypass graft surgery (CABG). We performed a retrospective study of PON associated with off‑pump CABG (OPCABG) to identify possible risk factors. Materials and Methods: 1442 patients underwent OPCABG over a 10‑month period from October 2008 to August 2009; PON was identified in four (0.28%) patients. A retrospective review of the charts was done to identify the patient characteristics, pre‑operative status, intra‑operative details, and ophthalmic examination details. Friedman test was used to compare the hematocrit (Hct) and the mean arterial pressure (MAP) values across the three time periods Pre‑, intra‑ and post‑operative periods. Results: All four patients were male, diabetic, and in the age range 51‑69 years. All patients noted unilateral or bilateral severe visual loss in the immediate post‑operative period, which was permanent. All the four patients had statistically significant decrease in the Hct (P < 0.039) and mean arterial blood pressure (P < 0.018) in the intraoperative and post‑operative period when compared to pre‑operative value. Conclusions: PON is a rare but definite possibility in patients undergoing OPCABG. Diabetes mellitus may be a risk factor. Perioperative hemodynamic abnormalities like decrease in MAP and anemia may play a role in the development of PON in OPCABG.