Related Experiment Videos
Improved peribulbar anaesthesia with alkalinization and hyaluronidase
J E Roberts1, B A MacLeod, R H Hollands
1Department of Pharmacology, University of British Columbia, Vancouver.
Canadian Journal of Anaesthesia = Journal Canadien D'Anesthesie
|September 1, 1993
Summary
The optimal peribulbar anesthesia involves combining hyaluronidase with alkalinized lidocaine-bupivacaine, achieving a pH of 6.7 for enhanced efficacy. This combination significantly improves anesthetic effectiveness compared to unadjusted solutions.
Area of Science:
- Ophthalmology
- Anesthesiology
- Pharmacology
Background:
- Peribulbar anesthesia is crucial for ophthalmic surgery.
- Optimizing local anesthetic mixtures can improve efficacy and patient outcomes.
- The influence of pH and additives like hyaluronidase on anesthetic performance requires further investigation.
Purpose of the Study:
- To evaluate the impact of pH adjustment and hyaluronidase on the efficacy of lidocaine-bupivacaine mixtures for peribulbar anesthesia.
- To determine the optimal conditions for enhancing peribulbar block effectiveness.
Main Methods:
- A prospective, double-blind, randomized study involving 100 patients undergoing ophthalmic procedures.
- Five groups received different formulations of bupivacaine (0.75%) and lidocaine (2%) with adrenaline.
- Variations included pH levels (3.9, 5.1, 6.7) and the addition of hyaluronidase (10 units/mL).
- Anesthetic efficacy was assessed by measuring residual patient movement 30 minutes post-injection.
Main Results:
- The most effective anesthetic solution combined hyaluronidase with alkalinization to a pH of 6.7 (P < 0.025).
- Hyaluronidase alone did not improve efficacy without alkalinization.
- Alkalinization alone was also ineffective in enhancing the anesthetic mixture's performance.
Conclusions:
- The efficacy of peribulbar anesthesia using lidocaine-bupivacaine mixtures is significantly enhanced by combining hyaluronidase with alkalinization to a pH of 6.7.
- These findings highlight the pH-dependent properties of local anesthetics and hyaluronidase activity.
- Optimizing anesthetic formulations can lead to improved clinical outcomes in ophthalmic surgery.