The Efficacy of 0.75% Bupivacaine with ph Adjustment and Hyaluronidase for Peribulbar Blockade: The Incidence of Prolonged Ptosis

Abstract

A prospective, double masked, randomised study was performed to compare the speed of onset of peribulbar anaesthesia using pH adjusted 0.75% bupivacaine, with and without the addition of hyaluronidase. No significant difference in speed of onset occurred due to the addition of hyaluronidase. There were 7 cases of post operative ptosis in the study group, including 1 case of orbital apex syndrome and 2 cases of transient 3rd nerve palsy. This incidence of post operative ptosis using pH adjusted 0.75% bupivacaine was statistically significantly greater than in a matched control group who received a 50:50 mixture of 1% lignocaine and 0.5% bupivacaine with hyaluronidase (p < 0.05). The possible causes of this increased incidence of post operative ptosis are discussed.

Eyelid Malposition After Cataract and Refractive Surgery

“…9 There is conflicting evidence with regard to the influence of the composition of the solution injected on postoperative ptosis. Mather et al 23 found an increased incidence (19% vs. 2.7%) of transient postoperative ptosis with 0.75% bupivacaine with pH adjustment compared with 1:1 1% lidocaine and 0.5% bupivacaine. 23 The enhanced toxicity may be a result of the higher concentration of bupivacaine (0.75% vs. 0.5%) or the pH adjustment, which can increase the overall availability.…”

“…Mather et al 23 found an increased incidence (19% vs. 2.7%) of transient postoperative ptosis with 0.75% bupivacaine with pH adjustment compared with 1:1 1% lidocaine and 0.5% bupivacaine. 23 The enhanced toxicity may be a result of the higher concentration of bupivacaine (0.75% vs. 0.5%) or the pH adjustment, which can increase the overall availability. 23 Epinephrine tends to potentiate the myotoxic effects.…”

“…23 The enhanced toxicity may be a result of the higher concentration of bupivacaine (0.75% vs. 0.5%) or the pH adjustment, which can increase the overall availability. 23 Epinephrine tends to potentiate the myotoxic effects. 18 The addition of hyaluronidase could also potentially increase the availability of the anesthetic and potentiate myotoxicity, but this has not been formally evaluated.…”

“…In addition, retrobulbar or peribulbar hemorrhage may potentiate the myotoxic effect of local anesthesia. 23 Van Lint blocks can create hematoma formation through local injection directly into the eyelid. 9 Fibrosis from resorbing hemorrhage can create adhesions and persistent ptosis.…”

Efficacy and safety of hyaluronidase 75 IU as an adjuvant to mepivacaine for retrobulbar anesthesia in cataract surgery

“…[13][14][15] Although numerous clinical studies confirm the positive effect of the use of hyaluronidase, some studies suggest a lack of effect. [15][16][17] The objective of the present study was to test the efficacy and safety of hyaluronidase on the onset and adequacy of ocular akinesia and anesthesia after retrobulbar administration. …”