Crystalloid/colloid versus crystalloid intravascular volume administration before spinal anesthesia in elderly patients: the influence on cardiac output and stroke volume.

Background: Hypotension is the most common cardiovascular response to spinal anesthesia. We compared the effects of crystalloid/colloid versus crystalloid administration before spinal anesthesia on cardiac output (CO) in elderly patients undergoing transurethral resection of the prostate.

Methods: Sixty male ASA I-III patients were randomized to one of three groups the control group received no intravascular volume preload, the saline group received 500 mL saline, and the hydroxyethyl starch (HES) group received 500 mL of saline plus 500 mL of 6% HES 130/0.