Effects of citrated whole blood transfusion in response to hemorrhage.
OBJECTIVE
Standard treatment for massive hemorrhage in dogs is infusion of whole blood or of packed red blood cells with fresh frozen plasma if whole blood is not available. Although most whole blood is collected using a citrate-based anticoagulant, knowledge of citrate's relevant non-anticoagulant effects is not widespread. Citrate's anticoagulant activity is achieved through chelation of divalent metal cations (e.g., magnesium, calcium), which may exacerbate cardiovascular and metabolic insults attributable to hemorrhage.


METHODS
Blood pressures, gas tensions, metabolites, and electrolytes; myocardial metabolites, pressures, and contractility; cardiac output; and left cranial descending and circumflex coronary artery flows were measured in 21 anesthetized dogs after hemorrhage was induced by collection of blood into a citrated reservoir to mean arterial pressure of 45 mm Hg for approximately 60 min (until arterial lactate concentration was 7.0 mmol/L), followed by a 1-h transfusion and 2 h of maintenance.


RESULTS
Arterial ionized calcium concentration, total peripheral resistance, and myocardial function decreased significantly during hemorrhage. All aforementioned responses but myocardial function continued to decrease during the initial 20 min of transfusion, then began to recover. Total peripheral resistance and end-systolic elastance were the only factors significantly related to calcium concentration.


CONCLUSIONS
Transfusion with citrated whole blood may significantly alter calcium concentration, negatively affecting myocardial and vascular function.
Blumenthal
S R
SR
Department of Comparative Medicine, Carolinas Medical Center, Charlotte, North Carolina, USA.
Williams
T C
TC
Barbee
R W
RW
Watts
J A
JA
Gordon
B E
BE
D000818:Animals; D000925:Anticoagulants / Q000009:adverse effects*; D001794:Blood Pressure; D002118:Calcium / Q000097:blood; D002302:Cardiac Output; D002951:Citrates / Q000009:adverse effects*; D003331:Coronary Vessels / Q000503:physiopathology; D004283:Dog Diseases / Q000628:therapy*; D004285:Dogs; D005260:Female; D006470:Hemorrhage / Q000628:therapy / Q000662:veterinary*; D008297:Male; D014655:Vascular Resistance
D000925:Anticoagulants; D002951:Citrates; D002118:Calcium