Serum anticoagulating

Serum and heparinized plasma are the preferred specimens for the measurement of phosphate. Concentrations of inorganic phosphate are about 0.2 to 0.3 nig/dL (0.06 to 0.10 mmol/L) lower in heparinized plasma than in serum. Anticoagulants such as citrate, oxalate, and EDTA interfere with formation of the phosphomolybdate complex. 

An investigation in patients taking long-term phenprocoumon treatment found that in the majority of cases phenytoin had no signifrcant effect on either serum phenprocoumon levels or the anticoagulant control, although a few patients had a fall and others a rise in serum anticoagulant levels, with consequent decreased or increased effect. ... 

When a sulfonamide is administered with an oral anticoagulant, the action of the anticoagulant may be enhanced. The risk of bone marrow suppression may be increased when a sulfonamide is administered with methotrexate When a sulfonamide is administered with a hydantoin, the serum hydantoin level may be increased. 

Use of the macrolides increases serum levels of digoxin and increases the effects of anticoagulants. Use of antacids decreases the absorption of most macrolides. The macrolides should not be administered with clindamycin, lincomycin, or chloramphenicol a decrease in the therapeutic activity of the macrolides can occur. Concurrent administration of the macrolides with theophylline may increase serum theophylline levels. 

Concurrent use of the fluoroquinolones with theophylline causes an increase in serum theophylline levels. When used concurrently with cimetidine, the cimetidine may interfere with the elimination of the fluoroquinolones. Use of the fluoroquinolones with an oral anticoagulant may cause an increase in the effects of the oral coagulant. Administration of the fluoroquinolones with antacids, iron salts, or zinc will decrease absorption of the fluoroquinolones. There is a risk of seizures if fluoroquinolones are given with the NSAIDs. There is a risk of severe cardiac arrhythmias when the fluoroquinolones gatifloxacin and moxifloxacin are administered with drains that increase the QT interval (eg, quini-dine, procainamide, amiodarone, and sotalol). 

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. 

Trypanosomiasis gulated blood on ice (not frozen). Unfixed thick films may be sent in addition. Send serum for serologic tests. Send 5 ml of anticoagulated blood as for filariasis (above). 

A universial anticoagulant does not exist, and it is therefore necessary to use, in clinical chemical analysis, serum or plasma prepared with a variety of anticoagulants. The role of the anticoagulant and preservatives on the observed value has been reviewed by Caraway (C2, C4) and by Winsten (Wll). 

Enzymes activities are particularly sensitive to the anticoagulant used in collecting the specimen. Heparin inhibits acid phosphatase (W16) and muramidase (Z5). Amylase activity is inhibited by oxalate or citrate (MIO), and lactic dehydrogenase and acid phosphatase lose activity in oxalate (C2). Alkaline phosphatase is stable in oxalate, oxalate-fluoride, or heparin, but 25 mAf citrate inhibits 50% of the activity, and as little as 50 mlf EDTA is completely inhibitory (B19). Leucine aminopeptidase is inhibited by EDTA, as is creatine phosphokinase (F3). Amylase activity has been reported to be only 83% of that in serum when oxalate or citrate-plasma is used (MIO). Heparin plasma appears to have no inhibitory effect. Despite the fact that clotting factor V is not stable in oxalate or EDTA, these are often used as anticoagulants to obtain plasma for prothrombin determinations (Z2, Z4). 

Drugs that may affect amiodarone include hydantoins, cholestyramine, fluoroquinolones, rifamycins, ritonavir, and cimetidine. Drugs that may be affected by amiodarone include anticoagulants, beta-blockers, calcium channel blockers, cyclosporine, dextromethorphan, digoxin, disopyramide, fentanyl, flecainide, hydantoins, lidocaine, methotrexate, procainamide, quinidine, and theophylline. Drug/Lab test interactions Amiodarone alters the results of thyroid function tests, causing an increase in serum T4 and serum reverse T3 levels and a decline in... 

Drugs that can decrease carbamazepine serum levels include charcoal, cisplatin, doxorubicin, felbamate, hydantoins, rifampin, phenobarbital, primidone, theophylline. The serum levels of oral contraceptives, haloperidol, bupropion, anticoagulants, felbamate, valproic acid, felodipine, tricyclic antidepressants, acetaminophen, ziprasidone, voriconazole, topiramate, tiagabine, olanzapine, and lamotrigine can be lowered by carbamazepine. 

Amiodarone increases the hypoprothrombinemic response to warfarin (an oral anticoagulant) by reducing its metabolism. Patients receiving digoxin may undergo an increase in serum digoxin concentrations when amiodarone is added to the treatment regimen. Amiodarone interferes with hepatic and renal elimination of flecainide, phenytoin, and quinidine. 

Erythromycin metabolites can inhibit cytochrome P450 enzymes and thus increase the serum concentrations of numerous drugs, including theophylline, oral anticoagulants, cyclosporine, and methylprednisolone. Erythromycin increases serum concentrations of oral digoxin by increasing its bioavailability. 

Iron for biosynthesis is transported through the bloodstream by the protein transferrin. The following procedure measures the Fe content of transferrin 10 This analysis requires only about 1 p,g for an accuracy of 2-5%. Human blood usually contains about 45 vol% cells and 55 vol% plasma (liquid). If blood is collected without an anticoagulant, the blood clots, and the liquid that remains is called serum. Serum normally contains about 1 pg of Fe/mL attached to transferrin. 

Piperacillin-Tazobactam (Zesyn) [Anribioric/Extended Spectrum Penicillin, Beta Lactamase Inhibitor] Uses Infxns of skin, bone, resp urinary tract, abd, sepsis Action PCN plus 3-lactamase inhibitor bactericidal i cell wall synth Dose Adults. 3.375-4.5 g IV q6h i in renal insuff Caution [B, M] Contra PCN or 3-lactam sensitivity Disp Powder for inj frozen, premix inj 3.25, 3.375, 4.5 g SE D, HA, insomnia, GI upset, serum sickness-like Rxn, pseudomembranous colitis Interactions T Effects W/ probenecid T effects OF anticoagulants, MTX i effects W/ macrolides, tetracyclines i effects OF OCPs EMS T Effects of anticoagulants monitor for signs of electrolyte disturbances and hypovolemia d/t D such as X- K+ may cause allergic Rxn in pts sensitive to PCN OD May cause N/V/D, resp difficulty, and Szs symptomatic and supportive... 

Measure the influence of heparin human serum samples containing normal levels of electrolytes were anticoagulated with 23.8, 35.7, 47.7 and 128 UI/mL of lithium heparin. 

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