An In Vitro Study Comparing the Effects of Hextend, Hespan, Normal Saline, and Lactated Ringer’s Solution on Thrombelastography and the Activated Partial Thromboplastin Time

• Published in: Journal of cardiothoracic and vascular anesthesia 2005-06, Vol.19 (3), p.358-361
• Main Authors: Dailey, Stephen E., Dysart, Christopher B., Langan, Daniel R., Slye, Michael J., Nuttall, Gregory A., Schrader, Lisa M., Williams, Brent A., Oliver, William C.
• Format: Article
• Language: English
• Subjects: Adult; Blood Coagulation - drug effects; Blood Platelets - drug effects; coagulation; Female; Hespan; Hextend; Humans; hydroxyethyl starch; Hydroxyethyl Starch Derivatives - pharmacology; In Vitro Techniques; Isotonic Solutions - pharmacology; Male; Middle Aged; Partial Thromboplastin Time - methods; Plasma Substitutes - pharmacology; Prospective Studies; Reference Values; Ringer's Lactate; Sodium Chloride - pharmacology; Thrombelastography - drug effects
• ISSN: 1053-0770; 1532-8422
• DOI: 10.1053/j.jvca.2005.03.014

Objective: The purpose of this study was to determine if 6% HES 450/0.7 (hydroxyethyl starch 450/0.7) in normal saline (Hespan) and 6% HES 450/0.7 in lactated Ringer’s solution (Hextend) have the same inhibition of the intrinsic coagulation pathway and platelet function. Multiple studies have suggested that 6% Hespan inhibits coagulation and increases chest tube drainage and transfusion requirements in cardiac surgical patients. There have been few studies of the effects of 6% Hextend, a relatively new plasma volume expander, on coagulation and the results thus far have been mixed. Design: A prospective in vitro study. Setting: A large academic medical center. Participants: Blood was collected from 30 healthy volunteers. Interventions: The blood was fractionated and diluted by 30% with Hextend, Hespan, normal saline, and lactated Ringer’s solutions, with a native sample for a control. Measurements and main results: Primary outcome measures were thromboelastography and activated partial thromboplastin time (APTT). For each of the TEG parameters, there was no difference between samples diluted with Hextend compared with Hespan ( p ≥ 0.112 in all cases). APTT did not differ significantly between samples diluted with Hextend compared with Hespan ( p = 0.562). Conclusions: This prospective in vitro study suggests that Hextend and Hespan, hydroxyethyl starch 450/0.7 in different base solutions, exhibit the same effect on platelet function as measured by the TEG.