Prevention of Complications of Eye Surgery

Study Overview
=================
Brief Summary
-----------------
This study was designed to investigate pre-operatively measured parameters of various anaesthetic regimes, iris color, sex, age, surgical time, severity of Marcus-Gunn Pupil (MGP), type of mechanical stimulation of eye, and number of extraocular muscle (EOM) under tension as predictors of significant OCR in pediatric strabismus surgery.

Detailed Description
-----------------
Objectives: Despite various proposed maneuver, successfully predicting an oculocardiac reflex (OCR) is difficult to achieve. This study was designed to investigate pre-operatively measured parameters of various anaesthetic regimes, iris color, sex, age, surgical time, severity of Marcus-Gunn Pupil (MGP), type of mechanical stimulation of eye, and number of extraocular muscle (EOM) under tension as predictors of significant OCR in pediatric strabismus surgery. Methods: Three hundred patients were randomized to one of three anesthetic regimes: group P: propofol (2 mg/kg), alfentanil 0.02 mg/kg, and atracurium 0.5 mg/kg at induction; group K: ketamine (2mg/kg), alfentanil 0.02 mg/kg, and atracurium 0.5 mg/kg at induction; group T: thiopental (5mg/kg), alfentanil 0.02 mg/kg, and atracurium 0.5 mg/kg at induction. OCR was defined as a 10% change in heart rate induced by traction. Results: Incidence of OCR was significantly lower in patients in group k compared with patients in group T or P. Chi-square test results showed that the occurrence of OCR was significantly associated with difference of iris color (P=0.01). The occurrence of the OCR did not correlate with sex, age, duration of surgery, iris color, severity of MGP, number of EOM under tension, and type of mechanical stimulation of eye. Type of mechanical stimulation of eye or number of EOM under tension increased risk of developing OCR by 0.81 (95% CI, 0.66-0.98) and 1.29 (95% CI; 1.12-1.63) respectively. Conclusions: Induction of anesthesia with ketamine is associated with least hemodynamic changes induced by OCR during strabismus surgery. The prediction of oculocardiac reflex propensity remains elusive.

Official Title
-----------------
phase2 Study of Prevention of Complications of Strabismus Surgery

Conditions
-----------------
Strabismus

Intervention / Treatment
-----------------
* Drug: KETAMINE, PROPOFOL, THIOPENTAL


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: 300 ASA physical status I or II patients, aged 2-18 years, who candidate for elective strabismus surgery Exclusion Criteria: trauma to eye, ASA III or IV, who had contraindication for using thiopental, ketamine, or propofol, had cardiovascular diseases or had taken cardiovascular drugs

Ages Eligible for Study
-----------------
Minimum Age: 2 Years
Maximum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Intervention/Treatment |
| --- |
|Drug: KETAMINE, PROPOFOL, THIOPENTAL|nan|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| incidence of OCR |  | TWO YEARS | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| TYPE OF DRUG PREVENTING OCR |  | 2 YEARS | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
oculocardiac reflex; strabismus surgery;