Corneal abrasion
- Most common damage to the eye which can occur during or after general anaesthesia is a
- Can lead to pain, blurred vision and considerable irritation for a few days.
- Almost all corneal abrasions heal without long-term effects on vision.
- Mech
- One cause is that the eye does not close fully during the anaesthetic.
- 60% do not close their eyes naturally when they have a general anaesthetic.
- The cornea is then exposed to the air and becomes dry.
- Fewer tears are produced during an anaesthetic, which also causes dryness in the eyes
- The dry cornea can then stick to the inside of the eyelid and the abrasion occurs when the eye opens again at the end of the anaesthetic.
- Corneal abrasion can also occur because something rubs against the exposed cornea.
- This may be one of the sheets used during surgery to cover the patient and keep the operation area sterile, or other equipment.
- How to prevent
- Small pieces of sticking tape are commonly used to keep the eyelids fully closed during the anaesthetic. This has been shown to reduce the chance of a corneal abrasion occurring.
- However, bruising of the eyelid can occur when the tape is removed, especially if you have thin skin and bruise easily.
- Not to wear eye makeup or mascara as small particles might irritate or damage the eye under the tape.
- Use a gel, an ointment or eye drops to moisten the eyes during your anaesthetic.
- These may be helpful if tape cannot be used or for certain operations in which the eyes need to be opened briefly during the operation.
- Eye ointments can sometimes cause temporary eye irritation or blurring of vision following an anaesthetic.
- Nothing rubs against the eyes.
- If your surgery requires you to be positioned lying on your front, your anaesthetist will use goggles, cushions and/or eyepads to protect your eyes.
- Fq
- After GA, it is uncommon to suffer from a corneal abrasion that causes symptoms.
- A large study of over 60,000 patients having a general anaesthetic found that 1 in 2,800 patients suffered symptoms from a corneal abrasion.
- Studies have also been done using a microscope to examine the eyes following an anaesthetic.
- These show that small corneal abrasions occur commonly.
- Around 1 in 25 patients may have a small corneal abrasion, which the patient does not notice.
- This occurs even when protective eye tape or ointment is used.
- Risk factors
- Lateral/prone positioning
- Long op time
- Surgery on your head or neck.
- Pre op poor vision
- What happens if I have a corneal abrasion?
- Corneal abrasions may be very painful. Healing usually takes a few days, after which the pain will stop completely.
- Treatment during this time can reduce pain and aims to prevent an eye infection developing.
- Eye drops, ointments and an eye patch may be used, as well as pain-relieving medicines.
- No surgical treatment is necessary.
- Almost all corneal abrasions heal with no visible scar and no long-term effect on vision.
- An eye specialist may be able to see a scar through a microscope.
- Contact lens users should take advice before using contact lenses again.
- Can I lose my sight during a general anaesthetic?
- Serious eye injuries during a general anaesthetic are very rare, but can lead to loss of eyesight.
- Two structures can be damaged:
- Retina
- Optic nerve
- Risk factors:
- Low blood pressure d
- Thromboembolic strokes
- The operations with higher risk are:
- Operations on the spine in the prone position (face down), and head down,
- Too much pressure on the eyeball during the operation can damage the optic nerve or interrupt the blood supply to the nerve and the retina.
- If the operation lasts more than six hours
- High blood loss
- Operations which require cardiopulmonary bypass (open heart surgery with use of a heart/lung machine)
- Neck dissection operations on both sides of the neck.
- The people with higher risk include those with other vascular diseases (high blood pressure, heart attack or stroke), diabetics and those with high red blood cell counts.
- Fq
- Very rare to lose sight in an eye after a general anaesthetic.
- For all operations under general anaesthetic is between 1 in 60,000 and 1 in 125,000 operations.
- However it is more likely (but still uncommon) in the high risk operations listed above.
- One study estimates that visual loss happens in 1 in 3,300 operations on the spine and 1 in 1,100 open heart operations.
Ptosis
- Pressure on nerves in the eyebrow area
- This is usually temporary and should recover
Post-Operative Vision Loss (POVL):
- Occurs in 0.03%.
- Due to
- Ischemic optic neuropathy
- Central artery occlusion
- Ischemic orbital compartment syndrome
- Occipital cerebral infarction.
- Proposed pathogenesis involves increased orbital venous and intraocular pressure due to external pressure during surgery.
- Risk factors include:
- Prolonged operative time.
- Intraoperative anaemia.
- Hypotension.
- High-volume infusions.
- Trendelenburg position.
- Rotation of the head.
- Applied ventral pressure, which may compromise blood flow to the optic nerve.
- Mitigation strategies:
- Routine use of a skull clamp
- (e.g., Gardner-Wells tongs, halo, or Mayfield)
- For long-segment spinal deformity surgery in some institutions.
- Pros
- Not applying external pressure to the orbit compared to horseshoe and foam headrests.
- Unobstructed visualisation of the face
- Controlled positioning of the cervical spine
- Facilitate surgical exposure.
Made with Bullet