Ultrasound Guided Peribulbar Anaesthesia - A Novel Dual Quadrant Injection Technique

Ultrasound Guided Peribulbar Anaesthesia: a Real-time Ultrasound Guided Technique With a Novel Dual Quadrant Injection

Peribulbar anaesthesia for ocular surgery depends on the spread of local anaesthetic throught the orbit to be successful and has a relatively high failure rate. This study will examine a novel ultrasound guided approach to peribulbar anaesthesia which should extend the depostion of local anaesthetic by using a dual quadrant injection technique. The study will assess the feasibility of this technique, how successful it is and whether any obvious safety issues arise with its use.

Study Overview

• Status: Completed
• Conditions: Eye Diseases
• Intervention / Treatment: Procedure: Ultrasound guided Dual Quadrant Peribulbar Anaesthesia

Detailed Description

Peribulbar anesthesia is widely used for anterior and posterior chamber ophthalmic procedures. It is a blind technique which is traditionally carried out by inserting a needle in the infero-lateral aspect of the orbit below the globe and injecting a volume of 8 - 12 mL of local anesthetic in the periorbital space. The goal of this inejction is to achieve akinesia and anesthesia of the eye sufficient for surgery. The technique has a relatively high failure rate of up to 30%. A failure or insufficient block requires a second or rarely a third peribulbar injection to achieve success. Ultrasound can be used to guide needles in the human body and has been successfully used in many anatomic locations for anaesthesia. This study will assess whether ultrasound can guide the block needle in ophthalmic anesthesia to deliver local anesthetic via a single entry into two discrete locations within the periorbital space - the first in the infero-lateral quadrant and the second in the infero-medial quadrant. If this can be done the investigators may achieve a higher success rate for this block with a lower volume potentially improving the quality of the block and its safety.

• Study Type: Interventional
• Enrollment (Actual): 22
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 88 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• ASA score less than III and ability to provide a written informed consent
• 22 patients presenting for opthalmic surgery

Exclusion Criteria:

• Coagulation disorder or anticoagulated with INR > 1.5
• Platelet count < 75 X 10*9/L
• Significant Myopia (axial length > 28mm)
• Patients unable to lie supine for 2 hours
• Patients with recent gas or silicone injections in/around the eye

Study Plan

How is the study designed?

Design Details

• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: US Guided Dual Quadrant Peribulbar block; Ultrasound guided Dual Quadrant Peribulbar Anaesthesia	Procedure: Ultrasound guided Dual Quadrant Peribulbar Anaesthesia; Landmark Guided single injection vs Ultrasound guided dual quadrant injection

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Block Success	Block will be deemed a failure if a supplementary block is required for the operative procedure	10 minutes post intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Block Quality (standardized Ocular Scoring System for akinesia and anaesthesia)	Block will be assessed according to a standardized Ocular Scoring System for akinesia and anaesthesia at 5 minutes and 10 minutes post block. This is a composite measure	5 and 10 minutes
Block Volume	Total volume of local anaesthetic will be recorded. Volume for each part of the dual injection technique will also be recorded. This is a composite measure.	1 minute
Duration of Procedure	The duration of the entire procedure will be recorded	1 to 10 minutes
Complications	Any complications during the procedure or in follow up clinical visits will be recorded	6 Weeks
Image Visualization	Operator's ability to see the needle in both the infero-lateral and infero-medial injection will be recorded. Ability to see perineural, retrobulbar and medial rectus spread of local anaesthetic will be recorded. This is a composite qualitative measure.	1 minute

Collaborators and Investigators

• Sponsor: Sunnybrook Health Sciences Centre
• Investigators: Principal Investigator: Paul G McHardy, MD, Sunnybrook Health Sciences Centre

Study record dates

Study Major Dates

• Study Start: January 1, 2012
• Primary Completion (Actual): March 1, 2012
• Study Completion (Actual): August 1, 2012

Study Registration Dates

• First Submitted: March 20, 2015
• First Submitted That Met QC Criteria: May 28, 2015
• First Posted (Estimate): June 2, 2015

Study Record Updates

• Last Update Posted (Estimate): June 2, 2015
• Last Update Submitted That Met QC Criteria: May 28, 2015
• Last Verified: May 1, 2015

More Information

Terms related to this study

• Keywords: Ultrasound guided peribulbar anesthesia
• Additional Relevant MeSH Terms: Eye Diseases; Physiological Effects of Drugs; Central Nervous System Depressants; Anesthetics
• Other Study ID Numbers: 424-2011