Onur Özlü, Süreyya Aydin, Ebru Salman A, Mustafa Aksoy and Mustafa Çağatay
Background: We aimed to investigate the effects of colloid preload or ephedrine bolus on ventricular wall stress by measuring plasma N terminal-Brain natriuretic peptide (NT-ProBNP) concentrations in patients undergoing arthroscopic knee surgery under spinal anesthesia. Methods: 60 patients ASA I-II, aged 20-60 were randomly assigned into two groups. Spinal anesthesia was induced with 0.5% 3 ml levobupivacaine. In Group K (n=30) patients received 500 ml of HES (130/0.4) solution 20 minutes prior to spinal anesthesia. In Group E (n=30) ephedrine 15 mg i.v was injected 1 minute after spinal anesthesia. SBP, DBP, MBP, HR were recorded before and 3,5,7,10,15,20,25,30,45,60,120,240 min. after spinal anesthesia spinal anesthesia and in both groups and in group K also recorded before preload. The plasma concentrations of NT-ProBNP were measured before and 1 and 3 hours after the spinal block.