Influence of hydroxyethyl starch 130/0.4 versus ringer lactate on renal function during acute normovolemic haemodilution in combination with controlled hypotension

ABSTRACT

The risks associated with banked homologous blood products are well known. Several techniques for management of surgical patients without homologous blood transfusion are available. Controlled hypotension and acute normovolemic haemodilution [ANH] have been proven effective in decreasing operative blood loss and the need for transfusion of allogenic blood. The combined reduction of oxygen carrying capacity and perfusion pressure during combination of ANH and controlled hypotension raises the concerns of hypoperfusion and ischaemic injury to the kidney. Forty patients undergoing major abdominal surgery were allocated to receive controlled hypotension induced by Na nitroprusside [mean arterial pressure 50 mm Hg] and acute normovolemic haemodilution [post ANH haematocrite 29%]. ANH was established by withdrawing venous blood into standard blood bags and replacing it by HES 130/0.4 [Group I] or RL [group II]. The shed blood was reinfused at the end of surgery. Subclinical alteration in renal integrity detected by sensitive markers of tubular damage has been reported in the absence of overt change in creatinine serum concentration and creatinine clearance in both groups. These markers have returned to normal values after 24 hours. Sensitive markers of kidney dysfunction have increased in both groups indicating moderate alterations in renal integrity during combination of ANH and controlled hypotension. Both volume replacement regimens did not differ with regard to kidney integrity