What is the most common complication of malpositioned lenses in the comatose or confused patient?

The most common complication of malpositioned lenses in a comatose or confused patient is corneal ulceration. This occurs because a malpositioned lens can lead to abnormal pressure or movement against the cornea, which can impair the corneal epithelium. In a patient who is unable to communicate or reposition themselves due to confusion or coma, the likelihood of prolonged pressure against the cornea increases. This can disrupt the protective barrier of the cornea and create an environment conducive to the development of ulcers.

Furthermore, the lack of blinking and tear production, as well as inability to adjust or remove the lens, can exacerbate the risk of corneal injury. Corneal ulcers can lead to serious complications including infections and may result in decreased vision or permanent damage to the eye if not addressed promptly.

In this context, while infection, red eyes, and lens damage may arise as potential complications in other scenarios, they are less common and often secondary to the issues caused by corneal ulceration in the specific situation of malpositioned lenses in comatose or confused patients.