Background: Continous spinal anesthesia (CSA) and frequently unilateral spinal anesthesia (USpA) are usually preferred for lower extremity surgeries. In this study, we aimed to compare the effects of these anesthetic techniques, on hemodynamic parameters, quality of anesthesia and complications in elderly patients undergoing hip surgeries. Methods: Forty patients aged 65 years and older, assigned to receive either CSA or USpA with 7.5 mg (1.5 cc) 0.5% hyperbaric bupivacaine initially. In CSA group, additional doses of 2.5 mg bupivacaine were applied until sensory block reach to T10. Maximum sensorial block level, time to reach the level of T10 (defined as onset time) and to regress to T12, hemodynamic parameters and ephedrine requirements were recorded peroperatively and during 2 h postoperatively. Results: Hemodynamic parameters, ephedrine requirements and regression of sensory block by two levels were similar in two groups. The onset time of anesthesia was significantly longer in USpA group than CSA group. Neuraxial anesthesia had to be converted to general anesthesia in 5 patients (25%) in CSA group and 1 patient (5%) in USpA group. Conclusions: We conclude that both USpA and CSA techniques have similar effects in elderly high risk patients. On the other hand, USpA is more preferable for surgeries with shorter durations due to its low cost and high success rate. [ABSTRACT FROM AUTHOR]