RESUMEN
PURPOSE: To compare the effectiveness for the patient of retrobulbar anaesthesia (RBA) and topical anaesthesia (TA) in cataract surgery by phacoemulsification. METHODS: We performed a prospective, randomized study on 115 patients operated at our clinic using the two anaesthesia techniques. The RBA group comprised 57 patients (20 women, 37 men; age 72 +/- 10 years); the TA group comprised 58 patients (20 women, 38 men; age 74 +/- 10 years). Measured parameters were: blood pressure; heart rate; blood oxygen saturation level; serum adrenaline, noradrenaline and cortisol levels; white blood cell count; indicated pain during the procedure, and pain as reported by the patient afterwards. Two psychological tests were used: the State-Trait Anxiety Inventory (STAI), and the patient-selected face-scale test. Statistical analysis was performed using Student's t-test and the chi-square test. Results were also analysed using a logistic regression model. RESULTS: Both types of anaesthesia were adequate for the surgical procedure. In the RBA group fewer patients experienced pain during surgery (p < 0.01) and fewer recalled any perioperative discomfort. With RBA the objective parameters were more stable than with TA, and systolic blood pressure was significantly lower (p = 0.01). The logistic model was able to predict perioperative pain with 93% certainty. Pain sensitivity was higher in younger patients and in patients with higher initial cortisol and noradrenaline serum levels. CONCLUSIONS: Both methods of anaesthesia are appropriate, but phacoemulsification with TA is more painful than with RBA. In hypertonic patients and younger patients who are more susceptible to pain, TA should be avoided or used in combination with individualized sedation.