Citrate anticoagulation

Sample Collection and Enzyme Stability. Serum samples are collected with chemically clean, sterile glassware. Blood is allowed to clot at room temperature, the clot is gently separated from the test tube with an applicator stick, and the blood is centrifuged for 10 minutes at 1,000 g. If the red cells are known to contain the enzymes whose activity is being measured, as in the case of LD, even slightly hemolyzed serums must be discarded. When acid phosphatase is to be measured, the serum should be placed immediately in ice and processed as soon as possible, or it should be acidified by the addition of a small amount of sodium citrate. Anticoagulants such as EDTA, fluoride and oxalate inhibit some serum enzymes. However, heparin activates serum lipoprotein lipase. 

Prothrombin time PT is performed by adding thromboplastin (tissue) factor and calcium to citrate-anticoagulated plasma, recalcifying the plasma, and measuring the clotting time. The major utility of PT is to measure the activity of the vitamin K-dependent factors II, VII, and X. The PT is used in evaluation of liver disease, to monitor warfarin anticoagulant effect, and to assess vitamin K deficiency. 

The saponin lysis method can be performed on either EDT A- or citrate-anticoagulated blood. Saponin solution to lyse erythrocytes is available in most laboratories for use with automated hematology instruments. 

Cat platelets tend to aggregate spontaneously in citrate-anticoagulated platelet-rich plasma (Tschopp 1970). Spontaneous aggregation was hypothesized to result from release of serotonin from platelets (Tschopp 1970). 

Citric acid is used in effervescing mixtures and granules. Formulations that contain citric acid are used in the management of dry mouth and to dissolve renal calculi, alkalinize the urine, and prevent encrustation of urinary catheters. Citric acid is also an ingredient of citrated anticoagulant solutions. 

Sample material EDTA, heparin or citrate anticoagulated whole blood. 

Pseudothrombocytopenia, defined as in vitro platelet aggregation in blood anticoagulated with ethylenediaminetetraacetic acid (EDTA), is clinically insignificant, but it must also be differentiated from thrombocytopenia induced by abciximab. In this case, microscopic examination of a peripheral blood smear, along with repeated platelet counts in citrate-anticoagulated blood samples, makes the distinction possible. ... 

The net removal of calcium during the continuous dialysis modalities depends on the calcium concentration of the dialysate fluid. Severe hypocalcemia has been reported when regional citrate anticoagulation has been used for CRRT in ARF and hepatic failure patients. " ... 

Meier-Kriesche HU, et al. Unexpected severe hypocalcemia during continuous venovenous hemodialysis with regional citrate anticoagulation. Am J Kidney Dis 1999 33 e8. 

Human Plasma pooled human plasma, mixed sex, sodium citrate anticoagulant (Innovative Research, Novi, Ml, USA) (tee Note 1). Store aliquots at -20 °C. Store thawed aliquot on ice and flash-fireeze the remaining blood sample at end of assay day. 

RCA right coronary artery radionuclide cerebral angiogram regional citrate anticoagulation... 

Ranby, M., Sundell, B., and Nilsson, T. K., Blood collection in strong acidic citrate anticoagulant used in a study of dietary influence on basal tPA activity. Thromb. Haemost 62, 917-922 (1989). 

Wester JPJ, Van Der Spoel JI, Dijksman LM, Zandstra DF. Citrate anticoagulation for continuous venovenous hemofiltration. Crit Care Med 2009 37(2) ... 

Fig. 3. Plasma-separator-membrane system and LDL adsorbent (a) and the continuous-flow blood-cell-separator centrifuge and inummoadsorbent column (b) in the arteriovenous shunt. Samples were derived from the flow system at A, B, and C in time intervals of 40 min. Pumps of the blood-cell-separator centrifuge (b) 1, citrate anticoagulant (1-3 mL/min) 2, heparin (1 mLi/min, 80,000 units/L of saline) 3, leukocytes 4, erythrocytes (10-40 mL/min) 5, plasma (10-40 mL/min) 6, lubrication (1 mL/min, 2000 units of heparin/L of saline) (51).

May JC, Rains TC, Yu LJ, Etz NM (1992) Aluminum content of source plasma and sodium citrate anticoagulant. Vox Sang 62 65-69 McDonald LJ, Mamrack MD (1988) Aluminum affects phosphoinositide hydrolysis by phosphoinositidase C. Biochem Biophys Res Commun 155 203-208 McGonigle R, Parsons V (1985) Aluminium-induced anaemia in haemodialysis patients. Nephron 39 1-9... 

Saner FH, Treckmaim JW, Geis A, Losch C, Witzke O, Canbay A, et al. Efficacy and safety of regional citrate anticoagulation in liver transplant patients requiring post-operative renal replacement therapy. Nephrol Dial Transplant 2012 27(4) 1651-7. 

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