Here’s what we found in answer to your question from a recent literature review. Surgeons from the Albany Medical College in New York collected data on complications during orthopedic surgery involving the spine. They specifically focused on problems that are unrelated to the surgeon’s technical skill.
Surgeons have found the ideal position for patients having spinal surgery that is done to correct spine deformities like scoliosis. Without knowing for sure, it sounds like that might be the type of procedure your friend had (based on your report of post-operative blindness).
The patient is placed prone (face down) with the head, neck, and hips supported in a neutral position. The bed is tilted to keep the head elevated slightly above the feet. The arms and legs are supported in a restful position without pressure on the joints.
Using this position has helped improve breathing, reduce pressure on the heart and lungs, lower pressure on the head and face, and decrease blood loss. Even with this good position, new problems such as blindness have cropped up. Pressure on the face and loss of blood supply over a long period of time can lead to this loss of vision.
Blindness is a fairly new complication probably from increased surgical time and more health problems in patients having surgery. The loss of vision can be permanent so preventing the problem is a high priority. As a result, different head support systems have been developed for use during spinal deformity corrective surgery. Special eye goggles have also been invented to help prevent this problem.
Even with these protective devices, surgeries can last many hours. Anything over six hours puts the patient at increased risk for loss of blood supply to the optic nerve (to the eye). This type of negative outcome is rare. It is understandable that blindness as a result of spine surgery seems like a stretch. Patients are warned ahead of time about this possible complication but may not take it seriously because it seems so far-fetched.
Patient safety is always a number one priority for surgeon, anesthesiologist, and all other operating room personnel. Everything possible is done to watch for any signs of patient compromise and take measures to prevent problems, especially something as serious as visual impairment. This may explain what happened to your friend but the full details may offer a more accurate description of what went wrong.