To evaluate and compare the effect of administration of intravenous ketorolac- midazolam or dexmedetomidine as adjuvants to general anesthesia on perioperative outcome during retinal surgery.

regarding patient registry; G power analysis was done was done to estimate the sample size. Assuming alpha (type I error) = 0.05 and beta (type II error) = 0.2 (power =80%), 18 patients per group would be sufficient to detect a difference 20 % in hemodynamics indices among the groups. A drop out 10% of cases was expected therefore 20 patients were required in each group to detect the difference.

- Statistical analysis: Data will be analyzed through SPSS (Statistical Package for Social Sciences). Program version 22. Distribution of data will be first tested by Kolmogorov-Smirnov test. Data is presented as mean and standard deviation (SD), median and range or numbers and percentages. For normally distributed data, one way ANOVA test will be used to compare between mean values of three groups with post hoc Bonferroni test for paired comparisons. Repeated measures ANOVA with post hock Bonferroni will be used for intra-groupal comparisons. For non-parametric data, Kruskal Wallis H test to compare between median values of 3 groups with Mann Whitney U test for paired comparisons. Chi Square test will be used for testing significance of categorical data. The P value ≤ 0.05 was considered as the level of statistical significance

Inclusion Criteria:

• American Society of Anesthesiologists physical status |or ||

Exclusion Criteria:

• Mental disorders.
• Psychological disorders.
• Neurological disorders.
• Hyper reactive airway disease.
• History of sleep apnoea.
• Severe cardiovascular disease.
• Respiratory disease.
• Hepatic disease.
• Renal impairment.
• Known sensitivity to any of study drugs.
• History of alcohol.
• History of drug abuse.
• Morbid obesity (body mass index >35).
• Pregnancy.
• Lactating women.
• Patient refusal.