Corneal Transplant / Keratoplasty

Anesthesia Implications

Position: Supine, Bed turned 90 degrees, Bed turned 180 degrees
Time: 1-2 hours (average)
Blood Loss: Very Low (5-10 ml)
Post-op Pain: Minimal (1-3)
Maintenance Paralytic: Ask surgeon

Anesthetic Approaches

  • GETT
  • GLMA
  • MAC, Nerve Block
The Anesthesia

Approach – Corneal transplants (often referred to as a keratoplasty, penetrating keratoplasty (PKP), or lamellar keratoplasty) typically require either general anesthesia or a retrobulbar block to prevent movement of the eyelids or Extraocular Muscles (EOMs). Movement could lead to globe distortion during the procedure. If needed however, this procedure can be performed with patient cooperation under topical anesthesia.

Nerve Block – If the approach is a MAC, the surgeon will do a retrobulbar block. Giving 60-80 mg of propofol is great to keep the patient comfortable/motionless during this junction.

Antibiotic – No IV antibiotic required.

Avoid Increased Intraoccular Pressure – Avoid any coughing, bucking, or valsalva maneuvers. Once the surgeon opens the eye, it is imperative to avoid increased intraoccular pressures which could cause the expulsion of intraocular contents.

180 degree turns (general considerations): Arrange lines and monitor cords in anticipation to turn. If turning right, keep cords and lines draped to the left. If turning left, keep cords and lines draped to the right. Have a circuit extension connected. Disconnect the circuit when turning and immediately reconnect.

The Pathophysiology

The cornea is an avascular structure that protects the eye and accounts for two-third of the eye’s refractory ability. There are many indications for corneal transplants. Indications may include persistent corneal edema, keratoconus (corneal thinning and bulging), corneal degeneration from endothelial failure, dystrophies, chemical/mechanical trauma, keratitis (corneal inflammation), etc.

The Surgery

Primary goals of this procedure are to restore the cornea’s integrity and establish clear vision. The donor cornea can only be stored for up to 2 weeks before transplantation surgery.

The surgeon will begin by inserting an eyelid speculum and securing the patient’s eye with sutures or a scleral fixation ring. The diameter of the cornea is measured to determine the appropriate size of the donor cornea transplant. The donor cornea is typically cut to be 0.25mm larger than the patient’s corneal bed. The donor cornea is then sutured in place, endothelial side down.