Pain During Pars Plana Vitrectomy With Sub-tenon Anesthesia

Study Overview
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Brief Summary
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Vitreoretinal surgery has evolved to less invasive procedures, and it is used to treat a wide range of diseases. So anesthesia for vitreoretinal procedures has evolved, promoting adequate analgesia while reducing risks to the patient. In the present study two types of procedures for anesthesia during vitreoretinal surgery are evaluated regarding the pain referred by the patient during the whole procedure: peribulbar anesthesia versus sub-tenon injection plus topical jelly anesthesia. Through the comparative analysis of the pain scale of the two groups it is expected that the two modalities present the same anesthetic efficacy, showing that the methods used may be equivalent.

Official Title
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Pain During Pars Plana Vitrectomy Comparing Peribulbar Anesthesia Versus Sub-tenon Injection Plus Topical Jelly Anesthesia

Conditions
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Retinal Disease, Diabetic Retinopathy, Maculopathy

Intervention / Treatment
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* Procedure: Topical lidocaine 2% jelly plus sub-tenon ropivacaine 10% injection
* Procedure: Peribulbar injection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients that have the diagnosis of epiretinal membrane, macular hole, complication of diabetic retinopathy such as vitreous hemorrhage or traction retinal detachment or other vitreomacular diseases that require treatment by pars plana vitrectomy. Exclusion Criteria: Previous pars plana vitrectomy in the studied eye. Previous scleral buckle surgery Uncontrolled arterial hypertension Any ocular surgery performed in the studied eye in the previous three months Medical or psychological condition that preclude study adherence

Ages Eligible for Study
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Minimum Age: 18 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: Group 1- Sub-tenon plus lidocaine jelly<br>Patients are going to be submitted to lidocaine 2% jelly topical anesthesia for 5 minutes then to sub-tenon injection of 2-4 ml of ropivacaine 10% previous to 23 G pars plana vitrectomy. | Procedure: Topical lidocaine 2% jelly plus sub-tenon ropivacaine 10% injection<br>* Lidocaine 2% jelly applied to conjunctival fornices for 5 minutes then injection of 2-4 ml of ropivacaine 10% in the sub-tenon space with a blunt cannula through a temporal inferior incision<br>|
| Active Comparator: Group 2- peribulbar<br>Patients are going to be submitted to peribulbar injection of 4-6 ml of ropivacaine 10% previous to 23 G pars plana vitrectomy. | Procedure: Peribulbar injection<br>* Peribulbar injection of 4-6 ml of ropivacaine 10%<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain score | Pain score referred by the patient measured with a Visual Analogue Scale (VAS). The VAS consists of ruler with 100 cm in length and scale from 0 to 100, where the numbers of this one are visible only in the side of the examiner. It is constructed from a metal ruler with a total length of one meter, supported by two transparent acrylic side supports and a sliding and movable metal weight on the metallic part of the ruler. Before the measurement of pain, the examiner will explain to the patients the functioning of the VAS. Each patient will be encouraged to pass the marker along the scale, with the help of the examiner. It will be made clear to him that point 0 is the point of the scale which represented no pain, what is considered the better outcome, and point 100 corresponded to the most intense pain he could feel. The patient will be asked about: Intraoperative pain - the intensity of pain throughout the procedure. | Once 30 minutes after the end of the vitrectomy surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Surgical complications | Surgical complications referred by the surgeon during vitrectomy | Once At the end of vitrectomy surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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vitrectomy, anesthesia, retinal disease, Pain, diabetic retinopathy, maculopathy