Medications

With the exception of antithrombotic medication, systemic drugs should be continued after surgery. Because of the bleeding aspirin may induce, acetaminophen (Tylenol) or mild narcotics should be taken to relieve pain.

Pain after glaucoma surgery is unusual. If pain is severe, the ophthalmologist should consider complications such as anterior or posterior hemorrhage, infection, or elevated IOP. Severe postoperative pain is an emergency and should be evaluated immediately by a member of the surgical team. Anxiety is responsible for much of the postoperative unrest. If reassurance is not adequate, a gentle tranquilizer such as diazepam (Valium) is better than sedation when the patient is recuperating at home.

Glaucoma medications should be continued in the unoperated eye. Fluctuations in IOP in the unoperated eye are common and may range several millimeters up or down during the weeks after surgery. Fluctuations are also seen in the untreated eye after laser trabeculoplasty and may be related to a central pressure-regulating mechanism. It may also be that the IOP is being measured more frequently and so physiologic or pathologic fluctuations are being seen.

Systemic aqueous suppressants such as carbonic anhydrase inhibitors (CAIs) reduce the flow of aqueous through the newly formed stoma in filtering surgery. The flow of aqueous inhibits scarring and helps form and maintain an adequate bleb. If possible, these

drugs should be discontinued for at least several weeks postoperatively. Our current practice is to replace systemic CAIs with a topical CAI in the unoperated eye. If this is insufficient to maintain IOP control, we begin to consider surgery in the unoperated eye rather than reinstituting systemic CAIs. In the postoperative setting, we tend to reserve CAIs for patients who have had bilateral surgery and still failed to achieve adequate IOP control.

Management of the operated eye depends on the procedure performed. Generally, the eye is patched for the first 24 hours. Topical steroid drops, such as prednisolone 1% or dexamethasone 0.1%, will reduce inflammation and scarring. Dose frequency varies from once hourly to twice daily for the first week. Steroids are effective in reducing inflammation and should be used abundantly when necessary. Often the steroids are administered in combination with a broad-spectrum antibiotic. If so, the antibiotic usually can be discontinued after a week or so. Steroid drops often are continued for 2–3 weeks or until the eye is quiet. In some cases, we continue using very-low-dose steroid drops for many weeks postoperatively. We always taper steroid drops rather than discontinuing them abruptly.

Some surgeons advocate systemic steroid therapy for patients in whom previous filtering surgery has failed or in those who have pre-existing inflammation. In routine cases, systemic steroids offer little advantage over topical therapy, but do pose additional risk.18

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