Anaesthesia for Ophthalmic Surgery: How "Retro" is the Peribulbar Block?

Completed

• Conditions: Ophthalmic Surgery; Parabulbar Block
• Interventions: Procedure: Ultrasound detection of local anesthetics spread

• Registration Number: NCT01258959
• Lead Sponsor: Sunnybrook Health Sciences Centre

Brief Summary

Ophthalmic surgery on the posterior section of the eye can either be performed under general anaesthesia or under local aneasthesia. The local anaesthesia is performed by injecting local anaesthetics behind the eye. There are two techniques: Either the needle is placed into the muscle cone formed by the four recti muscles - this is called intraconal or retrobulbar block, or the needle is placed outside of the muscle cone - this would be called extraconal or peribulbar. In our hospital the investigators usually perform the peribulbar block since it is easier to perform and has a smaller risk to injure the eye. The investigators however realize that the parabulbar block is sometimes very efficient and sometimes not, thus requiring a second or third injection. Now investigators are able to visualize where the local anaesthetics spreads with the help of ultrasound imaging. The aim of the study is to observe and to describe the incidence of intraconal spread of local anaesthetics when a peribulbar block is performed.

Detailed Description

Not available

Study Timeline

• Status Verified: 2010-12
• Study First Submitted: 2010-12-08
• Study First Submitted QC: 2010-12-10
• Study First Posted: 2010-12-13
• Study Start: 2011-01
• Primary Completion: 2011-06
• Study Completion: 2011-06
• Last Update Submitted: 2011-06-08
• Last Update Posted: 2011-06-09

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 100

Inclusion Criteria

-informed consent

Exclusion Criteria

• coagulation disorder
• INR over 1.5 and/or a platelet count less than 75 X 109/L,
• pathological myopia,
• inability of the patient to lie down for the operation for more than 2 hours
• lack of informed consent.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Ophthalmic surgery patients	Ultrasound detection of local anesthetics spread	Patients (men and women) of at least 18 years of age undergoing an ophthalmic procedure on the posterior section of the eye under local anaesthesia, i.e. with a peribulbar block. Inclusion and exclusion criteria for the study are the same as for the peribulbar anaesthesia.

Primary Outcome Measures

Name	Time	Method
Incidence of detectable retrobulbar spread of local anaesthetics during peribulbar injection.	At start (During peribulbar injection)	The outcome measure is the description of the spread of local anesthetics during the injection of the drug via the parabulbar needle.

Secondary Outcome Measures

Name	Time	Method
Assessment of block quality	20 Minutes after block	Assessment of the block quality by ophthalmic surgeon just before surgery starts and at least 20 minutes after the block: complete akinesia and anaesthesia or partial akinesia/anaesthesia.

Trial Locations

Locations (1)

Sunnybrook Health Science Centres; 🇨🇦 Toronto, Ontario, Canada