Dexmedetomidine in Topical Versus Peribulbar Anesthesia for Cataract Surgery

Dexmedetomidine as an Additive to Topical Versus Peribulbar Anesthesia for Cataract Surgery

The aim of this study is to compare efficacy of dexmedetomidine as an additive to topical versus peribulbar anesthesia for cataract surgery

Ocular surgery may be performed under topical, regional, or general anesthesia. The first recorded use of regional anesthesia for surgery was the instillation of cocaine into the conjunctival sac in 1884 by an Austrian ophthalmologist.

Davis and Mandel in 1986 described the peribulbar block, peribulbar block has delayed onset and need a higher volume of local anesthetic (LA) than a retrobulbar block. But the peribulbar block is away from intra-conal space and so produce fewer complication.

Dexmedetomidine is used as adjuvant to LA drugs in peripheral nerve block, brachial plexus block and intrathecal anesthesia with satisfactory results. A more recent study using dexmedetomidine (50 μg) with the peribulbar block before cataract surgery demonstrated an IOP decrease similar to IV dexmedetomidine administration and greater than a peribulbar block without dexmedetomidine.

Inclusion Criteria:

• American Society of Anesthesiologists (ASA) physical status classification I or II who scheduled for eye surgery

Exclusion Criteria:

• Patients who are younger than 18 years
• The usual contraindications for regional anesthesia such as patients refusing LA
• Clotting abnormalities
• Impaired mental status
• Allergy to any of the study medications
• patients had the severe cardiac disease
• chronic obstructive lung disease and a history of sleep apnea
• contraindications to the use of dexmedetomidine
• history or significant cardiovascular disease risk factors
• significant coronary artery disease or any known genetic predisposition
• history of any kind of drug allergy
• drug abuse
• psychological or other emotional problems
• special diet or lifestyle
• clinically significant abnormal findings in physical examination
• electrocardiographic (ECG) or laboratory screening
• known systemic disease requiring the use of anticoagulants.