Hypotony after trabeculectomy: don't stop anti-inflammatory drops & don't operate if post-op care inadequate.



The trabeculectomy involves creating a trap-door in the sclera underneath the upper lid. The goal of the follow-up care is basically to make sure that this trap door never heals properly so that it is leaking out a small amount of aqueous humour to the overlying conjunctival layer to lower the pressure inside the eye. It is vital that aggressive anti-inflammatory treatment be maintained in the early post-operative period to prevent proper healing. Unfortunately, sometimes my colleagues alter the originally planned post-operative regiment of aggressive steroid drops when they encounter too low a pressure or a shallow anterior chamber and jeopardize the chance of longterm success.

I’ve written many times before when blogging about some clinical outcomes about some of the challenges when performing glaucoma surgery in a tertiary centre and having colleagues in remote areas assist in the patients’ follow-up care. I guess it’s not always easy to make sure those helping in the follow-up care understand the treatment goal. When I am placed in the situation where a patient cannot stay in town to see me for all the required post-operative visits over 6-9 weeks, I always feel that the patients’ care could be compromised. Unfortunately, I do have to operate on patients who come from 100s of kms away who are not able to make multiple trips back for their ongoing care. If I just refused to do their surgery, they would probably be even worse off.

The patient in question this time, has glaucoma secondary to mesodermal dysgenesis. Over the years, I’ve treated many members of her family for this condition as the glaucoma damage can be devastating. This patient had the extra health burden of not just living remotely but also requiring chemo therapy for a recently diagnosed cancer that was required in yet another referral centre that is also 100s of kms away. For the post-operative care, she asked to be referred to an ophthalmologist in the town where she was going to be camped out for the next few months for her chemotherapy. I wrote the standard post-operative letter that explains continuing prednisolone acetate drops every 2 hours for the first three weeks, then decreasing to four times daily for three more weeks and slowly afterwards as long as there were no signs of inflammation. I also mentioned in the letter not to lyse the scleral flap sutures for at least 3 weeks in order to prevent hypotony. 

What I did not say in the letter but always emphasize in lectures is to never taper the prednisolone drops early if the eye pressure is low or anterior chamber is shallow to try to bring up the pressure. There is really only once chance to get the trabeculectomy to work properly and that is the first 4-6 weeks after the surgery. If the anterior chamber is a bit shallow, don’t worry as it will deepen when the ciliary body begins to work full time again after overcoming the initial shock of surgery. If you decreased the prednisolone drops in the first 1-3 weeks, then you are setting up the patient to have their surgery fail long-term. 

Can better communication help or is it hopeless? The remote ophthalmologist did try calling my office at the one week post-op mark. I was out of town (in fact at my son’s bedside for ten days after he underwent emergency surgery.) My office offered the ophthalmologist the chance to speak with my lead technician, who is very much aware of my post-operative treatment protocol but that ophthalmologist only wanted to talk to me. The patient’s anterior chamber was a bit shallow and the eye pressure somewhat low. He called a colleague of mine instead, who has a very different post-operative management philosophy, and they agreed to quickly reduce the prednisolone drops to try to raise the pressure and deepen the chamber. The remote ophthalmologist dictated a letter that was transcribed a couple of weeks later then mailed so that I received it one month post-op, three weeks after the letter was written, and at the point at which the patient was long since tapered down on the steroid drops she needs to make sure the surgery will be successful. I scribbled a nasty comment on the letter and faxed it back; not sure that this accomplished anything except probably assures me that this ophthalmologist will never want to deal with me again and still doesn’t help the patient as we cannot roll the clock back 3 weeks to increase the prednisolone dosing. Someone from that ophthalmologist’s office called in response to the fax to say that if I want to increase the dosage of the steroid drops then to have the patient come back to see me as they refused to increase the dosage again. Then the following week I received a letter from that ophthalmologist saying sarcastically thanks for calling to let him know about the patient (evidently he had not noticed the 4 page fax I sent him at one day post-op detailing that visit, the surgical note, and my standard post-op management.) He also said I darn wall need to take responsibility for the patient’s that I operate on (neglecting the fact that the patient had absolutely no way to come to see me and was hoping he could help out) and furthermore that he will be sure to never send me another patient (he actually has never referred me a patient in the more than 10 years I’ve been in Vancouver.)

So, here’s this poor patient, undergoing chemotherapy far from her home and more than one month out from having a trabeculectomy also far from her home. She has now received inadequate post-operative care and I’ve lost proper communication with the ophthalmologist who saw her for one post-operative visit and now refuses to see the patient again. 

Should I never operate on a patient who cannot stay or return for all their post-operative visits?