Comparison of the effectiveness of preoperative administration of intravenous Atropine and topical Tetracaine on the incidence and severity of Oculo Cardiac Reflex (OCR) in strabismus surgery

Comparison of the effect of intravenous Atropine and topical Tetracaine in the occurrence of Cardio-Ocular Reflex (COR) in Strabismus surgery.

A controlled, parallel-group, triple-blind, randomized, phase 3 clinical trial on 120 patients. The lottery was used for randomization.

This is a three-blind randomized clinical trial that was conducted on 120 patients who were candidates for Strabismus surgery in Faiz Hospital, Isfahan. After the approval of the ethics committee of the university, if the entry criteria were met, the patients (or their guardians) were included in the study and if they were satisfied, they were randomly assigned to the groups. In each group, the desired intervention was applied and the patient's clinical symptoms were recorded. The clinical caregiver evaluating the symptoms was different from the person applying the intervention and did not know the type of intervention. Even though the patients were included in the study, they were not aware of the type of intervention applied, so they were all blind. The data analysts also did not know the type of intervention applied in each group.

Inclusion criteria: patients 10 to 70 years old, candidates for Strabismus surgery, ASA anesthesia class I and II Non-entry criteria: medical sensitivity to Atropine, tetracaine, and artificial tears, history of cardiovascular diseases

Intervention group A: Patients in this group received 0.5 mg of intravenous Atropine immediately after anesthesia. Intervention group B: Patients in this group received 3 to 5 drops of 0.5% Tetracaine in 4 directions on the eyeball immediately after anesthesia. Control group C: Patients in this group received 3 to 5 drops of artificial tears immediately after anesthesia.

Heart Rate; Blood Pressure

This is a simple randomized clinical trial in which patients entered the study groups by lottery; The medicines and placebo were placed in sealed, opaque, and similar form packets which were coded. Each code was also written on a piece of paper, folded, and placed inside a box. After entering the operating room, each patient took one of the papers out of the box; The pocket with the same number was the intervention that was applied to him. This process continued till the number of patients reached the desired one.

This is a triple-blind clinical trial; In this way, before obtaining consent, patients were informed about the study but didn't know which group they would be in and therefore were blind. Also, the researcher who recorded the patient's symptoms was different from the nurse who injected the drug and didn't know the type of drug and was blind. Analysts who analyzed the data collected during the study also didn't know the type of intervention applied in each group and were blind.