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How To Do an Ophthalmic Nerve Block
Step by Step Description of Procedure
Check sensation in the ophthalmic nerve distribution. Wear gloves and use appropriate barrier precautions. Palpate the supraorbital rim and identify the supraorbital notch (the injection site). Cleanse the skin site with antiseptic solution, keeping it out of the eye. Place a skin wheal of anesthetic, if one is being used, at the supraorbital notch. Insert the needle farther and gently probe medially and slightly cephalad to elicit paresthesias.Do not insert the needle into the supraorbital foramen. When paresthesia occurs, withdraw the needle 1 to 2 mm. Aspirate to exclude intravascular placement and then slowly (ie, over 30 to 60 seconds) inject about 3 mL of anesthetic. While injecting, apply pressure (using your finger or some gauze) under the supraorbital rim to prevent swelling of the upper eyelid. If no paresthesia occurs during needle insertion, inject the anesthetic over the supraorbital notch (identified by palpation). Massage the area for about 10 seconds to hasten the onset of anesthesia. If these injections are unsuccessful, place a line of anesthetic subcutaneously along the orbital rim to block the branches of the ophthalmic nerve. Allow about 5 to 10 minutes for the anesthetic to take effect. 