Blood urea nitrogen test

Clark, P.M.S., Kricka, L.J. and Whitehead, T.P. (1981). Matrix effects in clinical analysis Commutability of control materials between the Ektachem, Beckman and SMA 12/60 glucose and urea methods. Clin. Chim. Acta 113, 293-303. Ektachem Blood Urea Nitrogen Test Methodology, I9I-8-8I-A (1981). Ektachem Glucose Test Methodology, 190-8-81-A (1981). 

Fig. 1. A multilayer coating dry chemistry test for blood urea nitrogen (BUN) where HI and I represent the acid base forms of a pH indicator, respectively...

INEFFECTIVE TISSUE PERFUSION RENAL The patient taking an aminoglycoside is at risk for nephrotoxicity. The nurse measures and records the intake and output and notifies the primary health care provider if the output is less than 750 ml/day. It is important to keep a record of the fluid intake and output as well as a daily weight to assess hydration and renal function. The nurse encourages fluid intake to 2000 ml/day (if the patient s condition permits). Any changes in the intake and output ratio or in the appearance of the urine may indicate nephrotoxicity. The nurse reports these types of changes to the primary health care provider promptly. The primary health care provider may order daily laboratory tests (ie, serum creatinine and blood urea nitrogen [BUN]) to monitor renal function. The nurse reports any elevation in the creatinine or BUN level to tiie primary health care provider because an elevation may indicate renal dysfunction. 

Administration may result in nausea, vomiting, diarrhea, rash, anemia, leukopenia, and thrombocytopenia Signs of renal impairment include elevated blood urea nitrogen (BUN) and serum creatinine levels. Periodic renal function tests are usually performed during therapy. 

Obtain blood urea nitrogen and serum creatinine tests to exclude renal failure. 

BUN, blood urea nitrogen CXR, chest x-ray DOE, dyspnea on exertion FBS, fasting blood sugar FEV, forced expiratory volume Gl, gastrointestinal LFTs, liver function tests SCr, serum creatinine, SOB shortness of breath. 

BUN, blood urea nitrogen Cl, calcineurin inhibitor CSA, cyclosporine IL-2RA, interleukin 2 receptor antagonist LFTs, liver function tests MMF, mycophenolate mofetil OKT-3, muronomab-CD3 RATG, rabbit antithymocyte immunoglobulin ... 

BUN, blood urea nitrogen CBC, complete blood cell count CNS, central nervous system CYP, cytochrome P-450 isoenzyme LFT, liver function test MAO, monoamine oxidase QTc, Q-T interval corrected for heart rate SCr, serum creatinine TMP-SMX, trimethoprim-sulfamethoxazole. 

Renal Effects. Blood urea nitrogen and serum electrolyte levels were normal in several individuals overcome by unknown concentrations of hydrogen sulfide gas in a pelt room (Audeau et al. 1985). One of these four patients had protein and blood in the urine initially, which was not detected upon later testing. Albumin and some granular casts were noted in the urine in another patient, but these findings were transient (Audeau et al. 1985). 

Current nutritional intake Complete blood cell count Serum electrolytes Sodium Potassium Chloride Bicarbonate Magnesium Phosphorous Calcium Serum glucose Serum albumin Markers for organ function Liver function tests Alkaline phosphatase Aspartate aminotransferase Alanine aminotransferase Total bilirubin Prothrombin time or International normalized ratio Renal function tests Blood urea nitrogen Creatinine Fluid balance Input Oral... 

Renal function tests Blood urea nitrogen Creatinine... 

Laboratory tests (e.g., blood urea nitrogen, creatinine, PSA) and urinalysis should be monitored regularly. In addition, patients should have an annual digital rectal examination. 

None of the exposures produced changes in clinical chemistry values (blood count, blood nitrate, blood urea nitrogen, serum enzymes, and serum electrolytes or urinalysis and nitrate and nitrite urinary excretion), spontaneous electrical activity of the cortex of the brain (detected by EEG), pulse rate and sinus rhythm, or pulmonary function. Visual and auditory acuity, exercise EKG, and time estimation tests did not differ from control values for any of the exposures. Only one of several cognitive tests was affected by exposure and the change occurred only in the four subjects exposed at 1.5 ppm. The test was taken during the time the subjects were experiencing severe headaches. 

Lab test abnormalities Aspirin has been associated with elevated hepatic enzymes, blood urea nitrogen and serum creatinine, hyperkalemia, proteinuria, and prolonged bleeding time. Dipyridamole has been associated with elevated hepatic enzymes. 

Drug/Lab test interactions The antianabolic action of tetracyclines may cause an increase in blood urea nitrogen. During doxycycline or minocycline therapy, false elevations of urinary catecholamine levels may occur... 

After resolution of the acute phase, maintenance levels of at least 0.8 mEq/L are necessary for optimal efficacy and should be checked once every 6 to 12 months, or more often if clinically indicated. Other follow-up tests include periodic thyroid function tests, blood urea nitrogen, serum creatinine, serum calcium (because lithium may cause hypoparathyroidism), and an EGG. Thyroid function tests and renal function should be monitored approximately every 6 to 12 months (see the section Maintenance/Prophylaxis Treatment in Chapter 10). 

Mydriasis may occur and may precipitate an attack of acute glaucoma in some patients. Other reported but rare adverse effects include various blood dyscrasias a positive Coombs test with evidence of hemolysis hot flushes aggravation or precipitation of gout abnormalities of smell or taste brownish discoloration of saliva, urine, or vaginal secretions priapism and mild—usually transient—elevations of blood urea nitrogen and of serum transaminases, alkaline phosphatase, and bilirubin. 

Kidney Blood tests Serum creatinine, blood urea nitrogen... 

Williams et al. (1997) described renal ischemia-reperfusion injury in rats. The animals were anesthetized and subjected to 45min of bilateral renal occlusion using atraumatic vascular clamps before renal perfusion was reestablished. After various time interval (up to lweek) blood urea nitrogen, creatinine and myeloperoxidase activity in the kidney were determined. The protective effects of an intracellular adhesion molecule monoclonal antibody were tested. 

As renal function improves, the excretion of urea increases and the concentration of urea in blood declines. So a reduction in blood urea nitrogen (BUN) is also a useful sign of returning kidney function. More complex tests, such as creatinine clearance, would be needed to check whether the glomerular filtration rate (GFR) has returned to normal. 

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