A Comparison of One-site and Two-site Peribulbar Anaesthesia for Cataract Surgery at Kaduna, Nigeria

A Comparison of One-site and Two-site Peribulbar Anaesthesia for Cataract Surgery at National Eye Centre, Kaduna. Nigeria

The aim of the study was to compare the efficacy and safety of single injection peribulbar anaesthesia against the classic double injection technique. This was a double blind randomized controlled trial involving two groups of consenting, adult Nigerian subjects with operable age-related cataract. An anaesthetic nurse who allocated the subjects to the two groups administered all the injections. The same surgeon operated on all the subjects while the principal investigator and a research assistant measured the outcome variables. All others were blinded as to subject allocation.

Injection of a mixture of lidocaine 2% + adrenaline 0.125mg/ml + hyaluronidase 15 International Units (IU)/ml into the inferior medial orbital compartment

Injection of a mixture of lidocaine 2% + adrenaline 0.125mg/ml + hyaluronidase 15IU/ml into the infero-temporal and supero-nasal orbital compartments

Time taken to achieve akinesia and anesthesia adequate for surgery. Ability to move the eye in each of four directions (up, down, right and left) was scored thus: 2- normal movement, 1- reduced movement and 0- flicker or no movement. Upper eyelid akinesia was scored as 2- normal opening, 1- reduced movement and 0- complete immobility. Maximum score of 10 and minimum of 0. Adequate akinesia was defined as a total score of <4 and was evaluated at 10 and 15 minutes.

After 10 minutes if akinesia score was more than 3, supplementary injections were given and the effect assessed was 5 minutes later

Systemic complications: dyspnoea, bronchospasm, impaired consciousness, intravascular injection etc Local complications: eyelid oedema, corneal oedema, conjunctival chemosis, conjunctival haemorrhage, globe perforation, vitreous haemorrhage, orbital haemorrhage etc

Pain was scored using a 4 point scale: 1 - no pain, 2 - mild pain, 3 - moderate pain, 4 - severe pain

Total volume of anaesthetic drug injected into the orbit to achieve anaesthesia and akinesia adequate for cataract surgery

Surgeon subjectively scored satisfaction with the anaesthetic block on a 4 point scale: 1- poor (25%), 2 - fair (50%), 3 - good (75%), 4 - excellent (100%)

Subjects were asked if they would agree to have the same anaesthetic procedure the next time they needed cataract surgery in the other eye

Inclusion Criteria: Age 50 years and above Diagnosed with uncomplicated senile cataract Visual acuity of <3/60 Exclusion Criteria: Impaired mental status Difficulty in speaking Known allergy to amide-type local anaesthetic agents and/ or hyaluronidase Previous surgery in the same eye Glaucoma Impaired ocular motility Eyelid abnormalities Patients with only one eye