Which anesthetic technique is best for your cataract patients? That depends on several variables, including how cooperative your patients are, how strong their lid squeeze is and your surgeons’ preferences. Here are the anesthesia techniques 3 high-volume ophthalmology centers favor.

 Pledgets speed topical technique

    Tuesdays at the Surgery and Endoscopy Center in Sebring, Fla., are cataract days with T. Hunter Newsom MD at the helm. We perform nearly all of the cases under topical anesthesia with light (1mg midazolam) intra-operative sedation. Upon admission, under the lower lid we place a small pledget that has been soaked in tetracaine, an antibiotic, an anti-inflammatory and dilating drops. We securely tape the eye shut to prevent blinking. (We give patients who take Flomax a drop of ophthalmic atropine to assist dilation). About 20 minutes later, remove the tape and assess the anesthesia and dilation. If necessary, administer additional tetracaine and neosynephrine drops. If the patient is noted to be a lid “squeezer” or is particularly concerned about intra-operative discomfort, apply a small amount of ophthalmic xylocaine gel.

    On the rare occasion where a block is required, we inject 6cc of 3% xylocaine with hyaluronidase using a peribulbar technique. After consideration of the possible negative effects of a retro-bulbar bleed vs. an increased risk of CVA or clot formation in patients who stop anticoagulant therapy, we’ll block patients who are anti-coagulated.

 Retrobulbar blocks

 The Spokane Eye Surgery Center in Spokane, Wash., a 3-OR ASC in operation for 22 years, performs 90 percent of its cataract cases with retrobulbar anesthesia, says Dan Simonson, CRNA, MHPA, managing partner and chief anesthetist. Once he starts the IV, he begins preparing the block. He applies monitors, usually a pulse oximeter. He then gives an appropriate dose of midazolam, usually about 1- 2mgs IV. He says he may also on rare occasion as indicated give other such adjuncts as fentanyl, diazepam or even propofol.

    Once the sedation takes effect, he performs the retrobulbar block. He typically injects 11/2ml of 0.5% xylocaine through the lower lateral conjunctiva. He then pulls the lid down and out and directs a 30 ga 3/8” sharp needle into the pre-septal area. “This is done to reduce the discomfort from the block needle that follows,” he says.

    The surgery center uses a 25 ga 13/8” Sprotte pediatric spinal needle for all its retrobulbar blocks. Depending on the length of the procedure or other considerations, the block mixture may consist of either 5ml of 2% xylocaine/75 u hyaluronidase (for 1 to 11/2 hours of surgical anesthesia) or a mixture of 0.75% bupivacaine/2% xylocaine/75 u hyaluronidase (for 2 to 3 hours), says Mr. Simonson. He inserts the needle through the anesthetized conjunctiva (although he may sometimes use a trans-dermal approach) and into the retrobulbar space. He then injects the entire 5ml and applies a 4x4 gauze to the closed lid. Place a Honan balloon with a pressure of 25mm/Hg for 15 to 30 minutes. He assesses the block and the patient’s level of sedation, and then takes him back to the operating room where he once again applies monitors. “The procedure is now ready to be performed,” says Mr. Simonson.

 Topical and blocks

Mr. Horowitz (unconscious@verizon.net) is chief anesthetist for ophthalmology at the Surgery and Endoscopy Center in Sebring, Fla.