Dexmedetomidine as an Additive to Local Anaesthesia to Decrease Intraocular Pressure in Glaucoma Surgery

Study Overview
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Brief Summary
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Nowadays, a number of cases with increased intraocular pressure and glaucoma have been shown a huge increase . This is because of the increase the geriatric population in the community and advanced medical care. Surgical correction, as a treatment, solves this problem greatly especially with the modern surgical techniques . Peribulbar block reduced the admission discharge time and reduced the burden on both the patients and the medical team. On the other hand, it carries the risk of increased intraocular pressure (IOP). Which, subsequently, limit its usage in glaucoma surgery. Dexmedetomidine, as an alpha 2 agonist, has a well-established role in decreasing intraocular pressure (IOP). This effect has been shown at a histological level and clinical level

Detailed Description
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Nowadays, number of cases with increased intraocular pressure and glaucoma has been shown a huge increase . This is because of the increase the geriatric population in the community and advanced medical care. Surgical correction, as a treatment, solves this problem greatly especially with the modern surgical techniques . Peribulbar block reduced the admission discharge time and reduced the burden on both the patients and the medical team. On the other hand, it carries the risk of increased intraocular pressure (IOP). Which, subsequently, limit its usage in glaucoma surgery . Dexmedetomidine, as an alpha 2 agonist, has a well established role in decreasing intraocular pressure (IOP). This effect has been shown at a histological level and clinical level . It has been tested in many studies before as an additive to local anaesthetic to augment the effect of the block and to achieve an accepted level of patient sedation (**). Many routes have been tested such as intravenous infusion, intramuscular injection and topically with the local anaesthesia . There is a debate about the best route and the optimum dose that can achieve the desired clinical effect with the least side effects. There is no study, till now, has examined the effect of Dexmedetomidine in a diseased eye with pathology that leads to increased IOP. This study states the hypothesis that Dexmedetomidine locally as an additive to local anaesthesia in different doses, not only will increase the duration of the block or achieve some level of sedation, but also can reduce the IOP in this diseased eye to a level that will help the surgical conditions and improve the surgical outcome.

Official Title
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Dexmedetomidine as an Additive to Local Anaesthesia to Decrease Intraocular Pressure in Glaucoma Surgery

Conditions
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Glaucoma

Intervention / Treatment
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* Drug: Dexmedetomidine to reduce the IOP


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Any patients who were ASA I-III, age more than 25 and less than 80 with diagnosed increased intraocular pressure and were legible for surgical correction Exclusion Criteria: Patients with known allergy to the medications to be given, ASA more than III, age less than 25 or more than 80, dementia, deafness, psychological disease, difficult to communicate, cannot lay flat, INR more than 1.7 or with significant coagulopathy

Ages Eligible for Study
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Minimum Age: 25 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: D50 Dexmedetomidine 50 micrograms group<br>peribulbar block was given using 10 ml of a mixture of local anesthetics. The mixture was composed of 5 ml of 0.5% bupivacaine +4.5 ml of 2% lidocaine +0.5ml of 50 micrograms of Dexmedetomidine with 150 IU hyaluronidase. | Drug: Dexmedetomidine to reduce the IOP<br>* Dexmedetomidine 50 micrograms group (D50) in which peribulbar block was given using 10 ml of a mixture of local anesthetics. The mixture was composed of 5 ml of 0.5% bupivacaine +4.5 ml of 2% lidocaine +0.5ml of 50 micrograms of Dexmedetomidine with 150 IU hyaluronidase.<br>* Other names: reduction of OCULAR HYPERTENSION;|
| Experimental: D25 Dexmedetomidine 25 micrograms group<br>peribulbar block was given using 10 ml of a mixture of local anesthetics. The mixture was composed of 5 ml of 0.5% bupivacaine + 4.5 ml of 2% lidocaine +0.5ml of 25 micrograms of Dexmedetomidine with 150 IU hyaluronidase. | Drug: Dexmedetomidine to reduce the IOP<br>* Dexmedetomidine 50 micrograms group (D50) in which peribulbar block was given using 10 ml of a mixture of local anesthetics. The mixture was composed of 5 ml of 0.5% bupivacaine +4.5 ml of 2% lidocaine +0.5ml of 50 micrograms of Dexmedetomidine with 150 IU hyaluronidase.<br>* Other names: reduction of OCULAR HYPERTENSION;|
| Placebo Comparator: control<br>peribulbar block was given using 10 ml of a mixture of local anesthetics without Dexmedetomidine. The mixture was composed of 5 ml of 0.5% bupivacaine +4.5 ml of 2% lidocaine +0.5ml with 150 IU hyaluronidase. | Drug: Dexmedetomidine to reduce the IOP<br>* Dexmedetomidine 50 micrograms group (D50) in which peribulbar block was given using 10 ml of a mixture of local anesthetics. The mixture was composed of 5 ml of 0.5% bupivacaine +4.5 ml of 2% lidocaine +0.5ml of 50 micrograms of Dexmedetomidine with 150 IU hyaluronidase.<br>* Other names: reduction of OCULAR HYPERTENSION;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| IOP before the block, after the message and before the surgical incision, after the end of the surgery | IOP before the block, after the message and before the surgical incision, after the end of the surgery | one hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Onset of the block | the time elapsed between the end of the block and the complete anaesthesia and complete or partial akainesia | 2 min |