Prevention of Complications of Eye Surgery (ocr)

Isfahan University of Medical Sciences

Status and phase

Completed

Phase 2

Conditions

Strabismus

Treatments

Drug: KETAMINE, PROPOFOL, THIOPENTAL

Study type

Interventional

Funder types

Other

Identifiers

NCT00478907

82390

Details and patient eligibility

About

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.

Full 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.

Enrollment

300 patients

Sex

All

Ages

2 to 18 years old

Volunteers

No Healthy Volunteers

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