Strabismus
Conditions
Keywords
oculocardiac reflex; strabismus surgery;
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.
Interventions
DRUGKETAMINE, PROPOFOL, THIOPENTAL
Sponsors
Isfahan University of Medical Sciences
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
DOUBLE
Eligibility
Sex/Gender
ALL
Age
2 Years to 18 Years
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| incidence of OCR | TWO YEARS |
Secondary
| Measure | Time frame |
|---|---|
| TYPE OF DRUG PREVENTING OCR | 2 YEARS |
Countries
Iran
Outcome results
None listed