Peribulbar anesthesia

Compared with the retrobulbar technique, peribulbar anesthesia provides similar anesthesia and akinesia for both anterior segment and vitreoretinal surgical procedures, but some patients may have inadequate akinesia and require additional injections. In addition, the onset time of blockade is not as rapid as with retrobulbar injection. Nevertheless, peribulbar anesthesia reduces the potential for inadvertent globe penetration, retrobulbar hemorrhage, and direct optic nerve injury. Although serious problems with retrobulbar and peribulbar injections are uncommon, numerous complications have been reported (Box 3-3). 

Johnston RL, Whitefield LA, Giralt J, et al. Topical vs. peribulbar anesthesia, without sedation, for clear corneal phacoemulsification. J Cataract Refract Surg 1998 24 407-410. 

Maclean H, Burton T, Murray A. Patient comfort during cataract surgery with modified topical and peribulbar anesthesia. J Cataract Refract Surg 1997 23 277-283. 

Peribulbar anesthesia is generally considered safer than retrobulbar anesthesia, with a lower incidence of adverse effects. It avoids deep penetration of the orbit and therefore inadvertent subarachnoid injection. It also seems to be safer with regard to the risk of bulb perforation (314). 

An arteriovenous fistula of the supraorbital vessels developed in a 75-year-old man after peribulbar anesthesia with a supplementary supranasal injection. He elected to have conservative management and the lesion remained asymptomatic and static in size over 10 months follow-up. 

Nine patients developed prolonged symptomatic diplopia (predominantly vertical) after peribulbar anesthesia with ropivacaine 1% plus hyalase 750 units (317). The mean time to resolution of the diplopia was 24 hours. The authors stressed the importance of warning patients undergoing peribulbar blockade with ropivacaine of the possibility of prolonged diplopia and queried its future use in routine cataract surgery. 

In 54 patients who received peribulbar anesthesia with either 1% ropivacaine or a mixture of 0.75% bupivacaine + 2% lidocaine there was no significant difference in akinesia scores or adverse effects reported the following day, notably headache, dizziness, nausea, scalp anesthesia, and diplopia, the latter occurring in 26% and 30% respectively (321). 

Peribulbar anesthesia with 1% etidocaine, 0.5% bupivacaine, and hyaluronidase has been evalnated in 300 patients (322). The mean volume administered was 17 ml. There was adequate analgesia in 85% of cases, and the other 15% required supplementation with a subtenon block. Akinesia occurred in 82% of cases. Two patients developed generalized seizures, and four developed severe hypotension. 

Postoperative strabismus and diplopia occurred in two of 200 patients undergoing cataract extraction under peribulbar anesthesia the symptoms resolved spontaneously by 6 months (324). 

Hamel P, Boghen D. Bilateral amaurosis following peribulbar anesthesia. Can J Ophthalmol 1998 33(4) 216-18. 

Belfort R Jr, Muccioli C. Hyphema after peribulbar anesthesia for cataract surgery in Fnchs heterochromic iridocyclitis. Ocul Immunol Inflamm 1998 6(l) 57-8. 

Hyaluronidase has found applications as an additive to the anesthetic agents used for peribulbar anesthesia for vitreoretinal surgery. Combinations of hyaluronidase with bupivacaine [119], lidocaine and epinephrine [120], lignocaine and adrenaline [121], or lidocaine and bupivacaine [122] were judged very... 

Cardiovascular Transient central retinal artery occlusion has been reported after peribulbar anesthesia [30 ]. 

A 74-year-old man developed orbital bleeding with chemosis, acute proptosis, and peribulbar hemorrhage after peribulbar anesthesia with 6 ml of lidocaine 2%, bupivacaine 0.75%, and 75 units of hyaluronidase without adrenaline. After ocular massage, compression with a Honan balloon was maintained at 30mmHg for 10 minutes, and the intraocular pressure normalized. Immediately after surgery the retinal circulation did not reperfuse, but on the first postoperative day the retinal vessels were perfused and the fundus looked normal. 

Ascaso FJ. Transient central retinal artery occlusion following peribulbar anesthesia for pars plana vitrectomy. J Clin Anesth 2010 22 577-8. 

Calenda E, Rey N, Compere V, Muraine M. Peribulbar anesthesia leading to central retinal artery occlusion. J Clin Anesth 2009 21 311-2. 

Vinerovsky A, Rath EZ, Rehany U, Rumelt S. Central retinal artery occlusion after peribulbar anesthesia. J Cataract Refract Surg 2004 30 913-5. 

Cardiovascular Three cases of central retinal artery occlusion after surgery with peribulbar anesthesia have been reported [47 ]. In two cases ropivacaine 0.75% (17 and 13 ml) was used in the third case the block was done with 14 ml of 2% mepivacaine. The authors suggested that these cases might be related to raised intraocular pressure due to the block or vasoconstriction caused by the local anesthetics. 

Demediuk OM, DhaMwal RS, Papworth DP, et al.A comparison of peribulbar and retrobulbar anesthesia for vitreoretinal surgical procedures.Arch Ophthalmol 1995 113 908-913. 

Walters G, Georgiou T, Hayward JM. Sight-threatening acute orbital swelling from peribulbar local anesthesia. J Cataract Refract Surg 1999 25(3) 444-6. 

Among the novel routes, subconjimctival injection allows circumvention of the barriers imposed by cornea and conjunctiva, resulting in higher levels in vitreous. The sub-tenon route is a good alternative to retrobulbar and peribulbar ones for administration of anesthesia due to less complications and avoidance of sharp needles. 

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