A peribulbar block is way of delivering regional anesthesia to the eye. It is often favored in lieu of general systemic anesthesia because it promises loss of movement to the muscles of the eye in addition to pain management. Muscular atrophy is especially important for delicate eye surgeries like cataract removal. Other advantagaes of peribulbar blocks are that they don't require a lot of equipment and produce less pressure in the eye than general anesthesia.
Instructions
Preparation
1. Add 5 ml of bupivacaine, 5ml lignocaine 2 percent and 75 cc of hyaluronidase to a 10 ml syringe. The hyaluronidase component helps the bupivacaine and lignocaine disseminate throughout the eye and prolongs their anesthetic affects.
2. Load a 25-gauge needle into the syringe.
3. Ask the patient to lie flat on his back.
4. Squeeze three drops of the amethocaine solution into the eye to be operated on three times with a one-minute interval between administrations. This will anesthetize the conjunctival sac so the patient won't feel the needle insertion for the peribulbar block.
First Injection
5. Ask the patient to focus on a central point on the ceiling to neutralize the position of the eyes.
6. Pull down the patient's bottom eyelid with the thumb of your less dominant hand. Insert the needle slightly 10 degrees upward with your dominant hand halfway between the lateral canthus and the lateral limbus. The needle will go in parallel to the floor of the eye.
7. Slide the needle in without excessive pressure until the hub or end of the needle tip is parallel to the iris.
8. Release your thumb and pull back on the syringe plunger to negatively aspirate it. Slowly inject 5 ml into the eye.
9. Reposition the needle if you encounter resistance while injecting the anesthetic. Resistance means that the needle is pushing against a muscle. The lower lid may swell with solution. Pull out the needle after the injection.
Second Injection
10. Insert the same needle into the eye's conjunctiva or corner closer to the nose bridge. Push it straight back gently but firmly until the needle's hub is level with the iris.
11. Release your thumb and pull back on the syringe plunger to negatively aspirate it. Slowly inject 5 ml into the eye. Slide the needle out after the injection.
12. Close the eye and cover it with adhesive tape. Apply gauze over the eye and gently press it down with your fingers to lower pressure in the eye's orbit.
Assessment
13. Remove the adhesive tape and assess the eye for the effect of the peribulbar block.
14. Check for drooping of the upper eyelid. The patient should not be able to lift the upper eyelid.
15. Lift the upper eyelid with your fingers to open the eye. Ask the patient to try to move his eyeball. He should not be able to move the eyeball or completely close his eyelid.
Tags: upper eyelid, with your, your thumb pull, adhesive tape, after injection