Heavy Bupivacaine in Peribulbar Block

Study Overview
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Brief Summary
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Most of the ophthalmic procedures are performed under local anesthesia as the patient is often elderly and with diseases. This may increase the risk of morbidity and mortality under general anesthesia. Different eye blocks have been practiced with great success. Moreover, it is associated with less hemodynamic instability, less respiratory depression, better postoperative pain relief, and less nausea and vomiting than general anesthesia. It is also associated with a reduction in stress response, maintained oxygen saturation and cardiovascular stability, in addition to the production of good akinesia and anesthesia alleviating occulo-medullary reflexes, all make local anesthesia more superior and safe technique.

Detailed Description
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Peribulbar anesthesia is widely practiced now as a safe local block for cataract eye surgeries. However, the limited duration of these blocks was shown to be the main problem encountered intra-operatively. Therefore, additional top-up doses are usually needed to continue the operation. Many kinds of research tried to introduce solutions in order to prolong the duration of the local anesthetics used. Many researchers tried different volumes, doses and adjuvant to local anesthetics, and studied their effects There are many studies that evaluated the effect of baricity of local anesthetic on the potency of motor block and the duration of motor and sensory blockade. However, no properly designed randomized, controlled studies have evaluated the feasibility and reliability of baricity local anesthetic agents used for the peribulbar block. Aim of the work prospective, randomized study was conducted to evaluate the effects of the baricitized bupivacaine used for the peribulbar block in patients undergoing posterior segment surgeries.

Official Title
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Heavy Bupivacaine Versus Plain Bupivacaine in Peribulbar Block

Conditions
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Anesthetics, Local

Intervention / Treatment
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* Drug: hyperbaric bupvacaine in Peribulbar block
* Drug: isobaric bupvacaine in Peribulbar block


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with American Society of Anesthesiology (ASA) I or II. 30-80 years old Patients scheduled for elective unilateral posterior segment surgeries. Exclusion Criteria: Patient's refusal. orbital deformity axial length( >28 mm ) increased intraocular pressure, or if they were blind in the contralateral eye, international normalized ratio (INR) > 1.5 allergy to local anesthetics, mentally retarded patients

Ages Eligible for Study
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Minimum Age: 30 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Health Services Research
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: hyperbaric bupvacaine group<br>Peribulbar block will be performed using a total volume of 7 ml 6ml hyperbaric bupivacaine 0.5% + hyaluronidase (50 IU) in 1ml saline | Drug: hyperbaric bupvacaine in Peribulbar block<br>* hyperbaric bupivacaine in Peribulbar block will be injected in the posterior segment surgery<br>* Other names: trial group;|
| Active Comparator: isobaric bupvacaine group<br>Peribulbar block will be performed using a total volume of 7 ml 6ml isorbaric bupivacaine 0.5% + hyaluronidase (50 IU) in 1ml saline | Drug: isobaric bupvacaine in Peribulbar block<br>* isobaric bupivacaine in Peribulbar block will be injected in the posterior segment surgery<br>* Other names: control group;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The onset and duration of lid and globe akinesia | scoring the ocular movements in each direction of gaze | 12 hours postoperative |