When Our Role is
to Triage and Stabilize

BY WILLIAM TOWNSEND, O.D.
SEPT. 1996

Bill, who works in a local auto repair shop, had been using an air chisel to break a rusted nut off a shaft when he suddenly felt a stinging sensation in his right eye. Shortly thereafter he noted that his vision in that eye was blurry. His presenting acuities with correction were: OD 20/400, OS 20/20^-2.

Bill denied any history of amblyopia and said his vision had been normal in both eyes before the accident. Pinhole did not improve the vision in the right eye. Gross external examination revealed anisocoria with the right pupil being round and reactive; the left pupil was slightly irregular in shape and reacted sluggishly to light. Slit lamp examination showed a steel splinter approximately 3mm x 0.5mm projecting through the right nasal limbus into the anterior chamber and into the iris midway between the limbus and pupil border. We noted grade II+ flare and red and white blood cells in the anterior chamber. The lens-iris diaphragm appeared to be pulled forward by the steel sliver, which suggested that the foreign body had penetrated the anterior lens capsule.

We explained the complexity and serious nature of this injury to Bill and insisted that he see an ophthalmic surgeon immediately.

DO'S AND DON'TS OF TRIAGE

In preparing Bill for his trip to the surgeon's office, there were several things we did and did not do.

First, we did not remove the foreign body. To have done so could have been disastrous. When a foreign body is removed from an eye in which the intraocular pressure is high or even normotensive, the iris can prolapse through the wound. Also, the iris can act as a wick, drawing microorganisms into the anterior chamber, greatly increasing the potential for endophthalmitis.

[IF YOU SUSPECT A METALLIC FOREIGN BODY IN THE
ORBIT OR GLOBE, DO NOT ORDER AN MRI.]

Second, we did not allow Bill the option of making arrangements for himself. Patients sometimes fail to realize the seriousness of their situation, and unless they are well-informed (and sometimes bullied or frightened), they may decide that surgery is not necessary. When a patient with an intraocular foreign body or a similar serious condition presents, it's essential that they understand that surgery is not optional, it is required.

Third, we did not let Bill leave our office until we had placed a protective shield over the injured eye. When a foreign body protrudes from the eye, patients may instinctively rub their eye. In this case, it was possible that the anterior lens capsule had been compromised, so it was essential to protect the eye from further manipulation.

Remember, too, that surgeons often culture the cul de sac prior to surgery and the presence of an antibiotic will compromise or invalidate the lab results. Also, when a foreign body involves the anterior segment, do not dilate the pupil. If you suspect an intraocular foreign body in the posterior segment, it is necessary to dilate, but pupil dilation in a case such as Bill's could have caused further damage.

Fourth, we instructed Bill not to eat or drink anything until he saw the surgeon. This is standard procedure in preoperative patient management. If the patient should choke or cough while the eye is in its present state, the Valsalva maneuver could have serious consequences. The orbital contents could be partially expelled through the opening, leading to hypotony and possibly choroidal effusion. More importantly, if the patient eats or drinks prior to surgery and develops problems with the anesthesia, he may vomit during the procedure. Aspiration of the vomitus may lead to pneumonia and even death.

If you suspect a metallic foreign body in the orbit or globe, do not order an MRI. The result would be similar to heating a piece of aluminum foil in the microwave. Tissue damage would almost certainly result. X-rays or a CT scan would be more appropriate.

There will be times when your role will be to triage secondary or tertiary care for a patient with an injury that exceeds your scope of practice. Be sure you know the proper procedures to maximize the patient's chances for a good outcome. CLS

Dr. Townsend is in private practice in Canyon, Texas, and is a consultant at the Amarillo VA Medical Center.