Independent Contributions of Hypothermia and Acidosis to Coagulopathy in Swine
Abstract
Background: Clinical coagulopathy occurs frequently in the presence of acidosis and hypothermia. The purpose of this study was to determine the relative contributions of acidosis and hypothermia to coagulopathy, as measured by current standard bedside and clinical laboratory analyses (i.e., bleeding time and pro- thrombin time). In addition, we investigated possible mechanisms of these effects using a modified prothrombin time test, thromboelastography, and thrombin kinetics analyses. An improved understanding of coagulopathy should facilitate hemorrhage control. Methods: Twenty-four pigs were randomly allocated into normal (pH, 7.4; 39 C), acidotic (pH, 7.1; 39 C), hypothermic (pH, 7.4; 32 Degrees C), and acidotic and hypothermic (pH, 7.1; 32 Degrees C) combined groups. Acidosis was induced by the infusion of 0.2N hydrochloric acid in lactated Ringer s solution. Hypothermia was induced by using a blanket with circulating water at 4 Degrees C. Development of a clinical coagulopathy was defined as a significant increase in splenic bleeding time. Measurements were compared before (pre) and 10 minutes after (post) the target condition was achieved. Results: Acidosis, hypothermia, or both caused the development of coagulopathy, as indicated by 47%, 57%, and 72% increases in splenic bleeding time (p less than 0.05, pre vs. post). Plasma fibrinogen concentration was decreased by 18% and 17% in the acidotic and combined groups, respectively, but not in the hypothermic group. Hypothermia caused a delay in the onset of thrombin generation, whereas acidosis primarily caused a decrease in thrombin generation rates. At 4 minutes quench time, thrombin generation in the acidotic, hypothermic, and combined groups were 47.0%, 12.5%, and 5.7%, respectively, of the value in the control group. There were no changes in serum tumor necrosis factor- and interleukin-6 in any group during the study.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 2005
- Accession Number
- ADA628088
Entities
People
- Angel V. Delgado
- Anthony E. Pusateri
- John B Holcomb
- John M. Uscilowicz
- Wenjun Zhou Martini
Organizations
- United States Army Institute of Surgical Research