The effects of colloid preload on hemodynamics and plasma concentration of atrial natriuretic peptide during spinal anesthesia in elderly patients

摘要

We evaluated the effects of moderate colloid preloading on hemodynamics and plasma concentration of atrial natriuretic peptide (ANP) during spinal anesthesia in elderly patients undergoing low extremity surgery. Twenty patients (aged 66-90 yr) were randomly divided into two groups. Control group (n = 10) received no prehydration, and hydration group (n = 10) received colloid (6% hydroxyethyl starch; HES) preloading of 8 ml.kg-1 before spinal anesthesia. Systolic blood pressure decreased significantly 10 and 30 min after spinal anesthesia in either group, and there was no difference between the groups in the incidence of hypotension. The concentration of ANP decreased significantly by 23% in control group, whereas it increased significantly by 86% in hydration group, suggesting that cardiac preload might increase with volume expansion effect of prehydration with HES. In conclusion, colloid preloading with moderate volume might prevent the decrease in cardiac preload with increasing ANP, whereas it did not prevent spinal-induced hypotension in elderly patients.