title: Regional citrate anticoagulation for hemorrhage experiments in rats.
abstract: BACKGROUND
  Hemorrhage alone without concomitant trauma often results in a hypercoagulable state that makes it difficult to prevent clotting within the blood withdrawal catheters. Although systemic administration of heparin can ameliorate this problem, heparin use has many additional actions that may confound interpretation of the hemorrhage experiments. The problem can be resolved by the use of a dual lumen catheter that anticoagulates only the blood within the withdrawal circuit. We describe the design of such a catheter and evaluate its function in studies of hemorrhagic shock in rats.
  
  
  METHODS
  Construction directions are provided for the dual lumen catheter along with a commercial source. The catheters were connected to computer controllable infusion syringes. Either citrate or heparin was used for regional extracorporeal anticoagulation. Rats were anesthetized and hemorrhaged to 40mmHg for more than 15min through the use of a computer program written in Labview. Ionized calcium measurements were obtained pre- and posthemorrhage.
  
  
  RESULTS
  The catheters remained patent throughout the experiments. There was no significant difference in the ionized calcium whether citrate or heparin was used for extracorporeal anticoagulation.
  
  
  CONCLUSIONS
  The dual lumen catheters are suitable for the study of hemorrhagic shock in rats without the need for systemic anticoagulation. The catheters can be used with computer-controlled hemorrhage procedures.
authors.affiliation: Walter Reed Army Institute of Research, Silver Spring, Maryland 20910, USA. Jim.atkins@us.army.mil
authors.forename: James L
authors.initials: JL
authors.lastname: Atkins
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Barrows
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Byzek
authors.forename: Chae-Hyuk
authors.initials: CH
authors.lastname: Lee
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Keesee
authors.forename: Andrea
authors.initials: A
authors.lastname: Edwards
authors.forename: James D
authors.initials: JD
authors.lastname: Oliver
mesh_terms: D000818:Animals; D000925:Anticoagulants / Q000008:administration & dosage* / Q000494:pharmacology; D001777:Blood Coagulation / Q000187:drug effects / Q000502:physiology; D057785:Catheters; D002951:Citrates / Q000008:administration & dosage* / Q000494:pharmacology; D006493:Heparin / Q000008:administration & dosage / Q000494:pharmacology; D008297:Male; D023421:Models, Animal; D051381:Rats; D017207:Rats, Sprague-Dawley; D012771:Shock, Hemorrhagic / Q000503:physiopathology*; D012984:Software
chemical_list: D000925:Anticoagulants; D002951:Citrates; D006493:Heparin