Peribulbar anesthesia in sclero-retinal surgery: two quadrants vs single injection

To evaluate the advantage of peribulbar anesthesia in two quadrants (infero-temporal and upper nasal) vs single injection technique (infero-temporal) for scleral rhegmatogenous retinal detachment surgery (RRD).

57 patients, aged between 33 and 75 years (57.01 ± 8.68), waiting for retinal detachment surgery, were randomized in two groups: a group S (29 patients), with single quadrant injection technique and a group C (28 patients) with two quadrants injection. Patients in Group S were injected in two quadrants with a 10 ml mixture containing Mepivacaine 2% 5 ml and Ropivacaine 0.75% 5 ml, with hyaluronidase 10 IU/ ml. Patients in group C were injected with the same anesthetic mixture in one quadrant. Number of additional injection, during surgery, in two groups, were reported. Pain was tested with VAS (Verbal Analogue Scale 0-10) after regional block, when muscles were insulated, during scleral buckling positioning, when conjunctive was closed and 6, 12, 24 hours after surgery.

The need for a second peribulbar injection of anesthetic occurred in 9 patients of group C (32.14%); further injection was necessary in 1 patient (3.57%) of group S during scleral buckling (VAS = 7), statistically significant (p <0.05). Postoperative VAS 6 - 12 - 24 hours after surgery was not significant.

The peribulbar anesthesia may be proposed in scleral surgery of retinal detachment; the injection in two quadrants secured solid and satisfactory anesthesia, increasing the outcome of retinal surgery in loco-regional anesthesia.