Assessment of the Effect of Clonidine for Cataract Surgery

Phase 2

• Conditions: Pain; Arrythmia
• Interventions: Drug: Clonidine; Drug: placebo

• Registration Number: NCT01677351
• Lead Sponsor: Federal University of São Paulo

Brief Summary

Clonidine, an agonist for alfa2 pre-synaptic, has been shown to be an effective adjuvant therapy for acute postoperative pain and has been shown an effect in sedative, intra-ocular and blood pressure and arrhythmias.The objective of this study is evaluating the analgesic effect of clonidine and its repercussion on arterial and intraocular pressure and arrhythmias for cataract surgery.

Detailed Description

After approved by the Ethical Committee and signed informed consent, 40 patients aged from 40 until 80 years undergoing cataract extraction will be randomized in two groups. Exclusion criteria will be myocardial ischemia, psychiatric disease, chronic pain, drugs dependency, chronic use of beta-blockage channel drugs. Group 2, patients will receive a single dose of 4mcg.kg-1 of clonidin2, 20 minutes before the surgical incision; group 1, patients will receive a sterile saline solution dose. Pain intensity will be assessed with the numeric rating scale. The antiarrythmic effect will be assessed with the continuous measure by Holter. The number of patients was calculated by Instat Graph® program. To detect difference in pain intensity of 3 between the groups by NRS, with 95% of power (estimated SD= 2.0), when the alpha level is set at 0.05, the sample should be of 20. Statistical analyses will be performed with parametric and nonparametric tests, considering the variety studied. The statistical program that will be utilized is Instat Graph®.

Study Timeline

• Study Start: 2011-07
• Status Verified: 2012-08
• Study First Submitted: 2012-08-01
• Study First Submitted QC: 2012-08-31
• Last Update Submitted: 2012-08-31
• Primary Completion: 2012-09
• Study First Posted: 2012-09-03
• Last Update Posted: 2012-09-03
• Study Completion: 2012-12

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 40

Inclusion Criteria

• cataract surgery
• topical anesthesia

Exclusion Criteria

• myocardial ischemia
• psychiatric disease
• chronic pain
• drugs dependency
• use of beta-blockage channel drugs

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
group 2: clonidine 4mcg.kg	Clonidine	this group (group 2) will receive 4mcg.kg-1 of clonidine 20 minutes before surgery.
Group 1: sterile saline solution	placebo	this group (Group 1) will receive a sample injection of sterile saline solution 20 minutes before surgery

Primary Outcome Measures

Name	Time	Method
intensity of pain	30 minutes before surgery, during the surgery	Pain intensity will be assessed by numeric rating scale.

Secondary Outcome Measures

Name	Time	Method
intraocular pressure	30 minutes and during the surgery	Intra-ocular pressure will be assessed with a manual tonometer of perkins.

Trial Locations

Locations (1)

Federal University of Sao Paulo; 🇧🇷 Sao Paulo, Brazil