Abstract: Nowadays, Phacoemulsification surgery is mostly carried out under local anesthesia. In this type of anesthesia the patient needs to be sedated. Because of painful intracameral injection, an Intravenus (IV) analgesia is also required using bolus dose of Fentanil or Remifentanil. Our main purpose was the comparison of the sedative effects of 2 models of Intravenous local analgesia during Phacoemulsification in cataractus patients. Moreover , to investigate the patient, surgeon satisfaction and complication rate in two groups. Material and methods: This Clinical Trial study was carried out on 64 patients with cataract who underwent phacoemulsification surgery in Baqiyatallah hospital in second half of year 2013. Patients with American Society of Anesthesiologists (ASA) Physical Status classification system ; ASA class I & II were chosen and randomly divided into two groups. The level of sedation was assessed using the Ramsay sedation(RS) scale. Moreover , along with sedative effect, patient, surgeon satisfaction ,Vital signs, rate of pain and complication rate were recorded and compared in two groups. Results: Thirty six patients were in Fentanil group with mean age of 64.71± 8.21 years and 28 in Remifentanil group with mean age of 65.2 ± 12.43. RS in Fentanil group was significantly higher than Remifentanil group (2.02±1.08 versus 1.42±1.19, p<.05). Rate of satisfaction of patients and surgeons was significantly higher in Fentanil group in comparison with Remifentanil group (p<.05). Side effects in Fentanil group was also significantly less than Remifentanil (p<.05). There was no significant difference in vital signs of patients in two groups neither before surgery nor after that. Conclusion: Results of this study show that, Fentanil has fewer side effects, more sedation effect and more patient and surgeon satisfaction in comparison with Remifentanil. The administration of fentanil appears to be a better choice as an analgesic with local anesthesia in cataract surgeryAbstract: Nowadays, Phacoemulsification surgery is mostly carried out under local anesthesia. In this type of anesthesia the patient needs to be sedated. Because of painful intracameral injection, an Intravenus (IV) analgesia is also required using bolus dose of Fentanil or Remifentanil. Our main purpose was the comparison of the sedative effects of...Show More