Coagulation and biochemical effects of balanced salt‐based high molecular weight vs saline‐based low molecular weight hydroxyethyl starch solutions during the anhepatic period of liver transplantation

Abstract

SummaryThe anhepatic period of liver transplantation is generally marked by a decrease in preload, and the infusion of hydroxyethyl starch (HES) solution is often an effective way to restore volume deficits in non-anaemic patients. However, the infusion of even limited amounts of HES solution during the anhepatic period may result in a worsening coagulopathy. Moreover, lactate-containing HES solution may cause some degree of biochemical derangements in compromised recipients. Therefore, we compared two different types of HES solutions: a balanced salt-based high molecular weight HES solution (670 ⁄ 0.75; high MW group) and a saline-based low molecular weight HES solution (130 ⁄ 0.4; low MW group) with respect to coagulation and biochemical profiles. First, in an in vitro study (n = 48), thromboelastography was performed to determine the effects of two HES solutions on coagulation after diluting (11%) the recipient's blood sample with each HES solution. Second, in an in vivo study, 500 ml of one of the two 6% HES solution was administered to 74 recipients (n = 37, each group) for 30 min after starting the anhepatic period. The coagulation profiles, including thromboelastography, and biochemical profiles were measured before and 30 min after the end of infusion. Less impairment in the thromboelastography profiles and aPTT was observed in the high MW group. A higher calcium concentration and less reduction in platelet count were noted in the high MW group, but lactate accumulation was greater. In conclusion, a balanced salt-based high molecular weight HES solution is a more effective volume replacement during the anhepatic period of liver transplantation with respect to coagulation than a saline-based low molecular weight HES solution, although lactate accumulation is a possible concern. During the anhepatic period of liver transplantation, clamping and compression of large veins (i.e. inferior vena cava, portal vein) decrease venous return and often produce haemodynamic instability. In this case, infusion of hydroxyethyl starch (HES) solution is helpful in restoring circulating volume and obviates the need to infuse large amounts of rapidly extravasating crystalloid solutions in non-anaemic recipients, most of whom present with a low oncotic pressure. Other colloid alternatives, such as albumin and fresh frozen plasma, are frequently infused during liver transplantation, but are expensive, in limited supply and risk infection [1].Despite the many well-known benefits of HES solution, its use is associated with coagulopathy. The mechanisms of coagulation impairment by HES solution include dilutional coagulopathy and inhibitions of endothelial cell activation, von Willebrand factor release, platelet function, and fibrin polymerisation [2][3][4]. Although coagulopathy is typically associated with infusion of a large volume of HES solution, it may be exacerbated further even with an otherwise safe volume of HES solution (i.e. 500 ml) in liver transplantation recipients who manifest pre-operative coagulopathy [5,6].

Meta-analysis of high-versuslow-chloride content in perioperative and critical care fluid resuscitation

“…When administered in large volumes, 0·9 per cent saline has been shown to cause coagulopathy. Total volumes of fluid administered did not vary substantially between the groups ( Table S3 , supporting information), suggesting that dilutional coagulopathy does not account for the observed differences in transfusion.…”

Evaluation of the pulse pressure variation index as a predictor of fluid responsiveness during orthotopic liver transplantation

“…We chose this regimen because of two main reasons: first, cirrhotic patients might potentially have some degree of capillary leakage, and a colloid would theoretically remain inside the intravascular space more readily; secondly, we chose a relatively small infusion volume for each FC because of concerns of colloid-induced coagulopathy, as it has been shown that the volume threshold to induce coagulopathy may be unexpectedly low in cirrhotic patients undergoing OLT. 26 Another explanation for our results would be the setting where this study was performed. Accordingly, acute changes in sympathetic tone and preload status might be particularly frequent during major abdominal surgery.…”

Hyperchloremia is associated with 30-day mortality in major trauma patients: a retrospective observational study

“…Associations between fluid overload and morbidity and mortality were reported by the Fluid and Catheter Treatment Trial (FACTT) and other trials in surgical patients [ 22 – 24 ]. When administered in large volumes, NS has been shown to cause coagulopathy [ 25 , 26 ]. The mechanisms underlying saline-induced coagulopathy are not fully known.…”