Term
| The osmolality of a urine sample or serum specimen is measured by a change in the |
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Definition
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Term
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Definition
| the difference between the calculated and measured osmolality value |
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Term
| The formula for calculating serum osmolality that incorporates a correction for the water content of plasma is |
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Definition
| (2 Na + Glucose / 18) + (BUN/2.8) |
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Term
| The osmolal gap is defined as measured Osm/kg minus the calculated Osm/kg. The average osmolal gap is near |
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Definition
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Term
| The solute that contributes the most to the total serum osmolality is |
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Term
An adult diabetic with renal complications has the following results. calculate theoretical osmolality
Sodium = 133 mEq/L
BUN = 84mg/dL
Glucose = 486 mg/dL
Creatinine = 5 mg/dL |
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Definition
(2 Na + Glucose)/ 18 + BUN/2.8
2 (144) + 486/18 + 84/2.8
323 mOsm/kg |
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Term
A patient had the following serum results, calculate osmolality:
Sodium = 140 mEq/L
Glucose = 95 mg/dL
BUN = 10 mg/dL |
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Definition
2(Na) + glucose/18 + BUN/2.8
2(140) + 95/18 + 10/2.8
289 mOsm/kg |
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Term
| List the 4 colligative properties of solution |
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Definition
| Osmotic pressure, decreased vapor pressure, decreased freezing point, and increased boiling point |
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Term
| One mole (Avagadro's number of molecules) of non-ionizing solute dissolved in one kilogram of water will ________ the freezing point by ______degrees C. |
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Definition
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Term
| The concentrating abilities of the kidney are the best evaluated by |
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Definition
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Term
| The osmolality of a solution is dependent upon |
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Definition
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Term
| An increase in the osmolar gap may often be associated with |
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Definition
| ingestion of toxic substances, ingestion of alcohol, presence of ketones |
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Term
| List the four primary constituents found in serum that are measured by osmometry |
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Definition
| Na+, Cl-. Glucose and BUN (urea) |
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Definition
| techniques to measure the concentration of the dissolved solute particles in solution that contributes to osmotic pressure |
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Term
| When referring to osmolality, what are the units measured? |
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Definition
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Term
| Explain the difference between osmolarity and osmolality |
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Definition
| Both are measurements of concentration of solutes in a solution, but osmolarity is a measurement of the concentration per volume, which is temperature dependent. Osmolality is concentration relative to mass of solution and is temperature independent |
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