Vitrectomy
Anesthesia Implications
Position: Supine, arms free at side, Bed turned 90 degrees
Time: 30-60 min (short)
Blood Loss: Very Low (5-10 ml)
Post-op Pain: Minimal (1-3)
Maintenance Paralytic: No
Blocks: Retrobulbar
Anesthetic Approaches
- MAC
Approach – Very common to give 0.5 – 2mg versed preop. Intraoperatively, 20 – 60mg propofol or 500 – 750 mcgs of alfenta are administered right before the retrobulbar block.
Balance Sedation – Sedation should be sufficient to limit excessive patient movement/anxiety, but if too sedated, some patients will tend to snore, which will create difficulties for the surgeon.
A vitrectomy is performed to remove some or all of the vitreous humor (gel-like fluid that fills the eye) from the eye. The vitreous is replaced with saline, silicone oil, or a gas bubble. An eye speculum will be used to keep the eye open. The surgeon begins by performing a retrobulbar block. Thereafter, the surgeon will make a small incision in the eye and use 2-3 trocars to remove the vitreous humor.
There are two types of vitrectomy procedures – anterior and posterior (posterior pars plana vitrectomy). In cases of trauma, or even surgery (eg. cataract, corneal or glaucoma surgery), the vitreous humor will breach its cavity (otherwise called the vitreous cavity) and leak from the pupil into the most anterior parts of the eye. An anterior vitrectomy involves the removal of that vitreous humor from anterior segments of the eye where it has “leaked” or breached its cavity. A posterior vitrectomy is performed by a retina specialist. The procedure is performed by removing vitreous humor from the posterior part of the eye for conditions that affect the tissues of that area (eg. the retina). Entry to remove vitreous humor is made at the pars plana, which is where the iris meets the sclera. Entry at this point will avoid trauma/damage to the retina.
Indications for a vitrectomy – Some of the indications for a vitrectomy include diabetic retinopathy, retinal detachment, vitreous hemorrhage, infection in the eye, a hole in the macula, and complications after cataract surgery.
