Basic Chemistry Flashcards

Question

Clinical manifestations of Hyper-K

Answer 1

irritability, N/V/D, intestinal colic & rarely flaccid paralysis

Answer 2

peaked T waves, widened or biphasic waves of the QRS complex

Answer 3

Hemolysis Repeated fist clenching during phlebotomy Specimen drawn above IV line containing K+ infusion Renal failure (acute & chronic) Hypoaldosteronism (primary or secondary) Heparin Drugs that inhibit K+ excretion (spirinolactone, triamterene, ACE-I ARBs, NSAIDs, and trimethoprim) Rhabdomyolysis Severe infection Vigorous exercise Metabolic acidosis Insulin deficiency Excessive intake of K+

Answer 4

depends on (1) degree of hyperkalemia (2) degree of cardiac & neuromuscluar involvement (3) duration of the hyperkalemia

Answer 5

if K+ is < 6.5 mEq/L & no ECG changes, usually safe to try correcting underlying cause & restrict K+ intake

Answer 6

when K+ is > 6.5 mEq/L with EKG changes or > 7.0 mEq/L without EKG changes. Monitor the EKG continuously Ca+ (CaCl- or Ca²+ gluconate 5-30 mL IV) Sodium Bicarbonate (NaHCO3) Regular insulin (5-10 units IV) + glucose 50% (D5W, D5 1/2NS, or D5NS) Can also administer albuterol Promote K+ elimination with Na+ polystyrene (Kayexalate) or dialysis in patients with coexistent renal failure

Answer 7

Reference Range: 96 – 106 mEq/L Panic Values: < 70 or > 120 mEq/L Major extracellular anion; important in cellular hyperpolarization (especially neurons) Moves in & out of cells; forms NaCl-, hydrochloric acid, KCl- & CaCl- Important in CSF formation & in GI secretions Changes in Na+ commonly affect Cl- levels b/c it is commonly attached to the + charge of Na+

Answer 8

↓ Cl- levels < 96 mEq/L Always associated with a metabolic alkalosis & oftens results in a paradoxic aciduria Cl- is measured to calculate the anion gap Causes - vomiting, gastric suction, burns, CHF, water intoxication

Answer 9

seldom a primary problem therefore the sgs/sxs will depend Tx – treat the underlying cause, IV fluids

Answer 10

↑ Cl- levels > 106 mEq/L Usually associated with a tendency towards acidosis (HCO3 loss) Causes – dehydration, Cushing’s syndrome, hyperventilation, diarrhea, diabetes insipidus, hyperparathyroidism, & salicylate intoxication

Answer 11

Clinical manifestations - acid-base alterations Tx – treat the underlying cause

Answer 12

Serum Reference Range: 22 – 29 mEq/L CO2 is transported in 3 forms (1) attached to Hgb (2) dissolved CO2 in plasma (3) and as HCO3- in the plasma Dissolved CO2 & HCO3- make up about 77% of the CO2 that is transported in the extracellular fluid 90% of CO2 in blood is in the form of HCO3-

Answer 13

Increased levels – metabolic alkalosis, respiratory acidosis (hypoventilation states), severe vomiting or gastric drainage Decreased levels – metabolic acidosis, respiratory alkalosis (disorders causing hyperventilation)

Answer 14

Anion Gap = Sodium – (Chloride + CO2) Normal Anion Gap is between 8 – 14 mEq/L Difference between cations & anions reflects concentrations of other anions that are present in ECF but are not routinely measured, but may become ↑ in the acidotic state Helps distinguish type of metabolic acidosis (wide anion gap vs. normal anion gap)

Answer 15

Reference Range: 275 – 295 mOsmol/kg Measured osmolality is the measure of the number of dissolved solute particles in solution Predominant osmotically active particles in the ECF are Na+ & its attendant anions (Cl- & HCO3-), BUN, & glucose

Answer 16

2 (Na+) + Glucose/18 + BUN/2.8 Serum osmolality ↑ with dehydration & ↓ with overhydration

Answer 17

Difference between measured & calculated serum osmolality is called the osmolar gap (usually < 10 mOsm) Presence of gap > 10 mOsm suggests the presence of an unmeasured osmotically active substance (ETOH, acetone, mannitol)

Answer 18

BUN interpreted in conjunction with creatinine BUN – creatinine ratio provides useful diagnostic info BUN is less accurate & specific for renal fx compared with creatinine Less interfering factors that can alter creatinine levels

Answer 19

Blood Urea Nitrogen (BUN) Reference Range: 6 – 20 mg/dl Panic Values: > 100 mg/dl Synthesized in liver & along with CO2, constitutes final product of protein metabolism Proteins→ amino acids→ free ammonia→ urea → deposited in blood & renal excretion The amount of excreted urea varies directly with protein intake

Answer 20

Impaired renal function Chronic renal disease Urinary tract obstruction Hemorrhage into GI tract Diabetes mellitus with ketoacidosis ⇑ protein intake or catabolism Anabolic steroids Dehydration

Answer 21

Liver failure Acromegaly Malnutrition Impaired GI absorption Overhydration Interfering factors – Diets, ↓ in children & women, pregnancy, aggressive IVF, many drugs

Answer 22

Reference Range: 0.5 – 1.2 mg/dl Critical Values: > 4 mg/dl Catabolic product of creatine phosphate used in skeletal muscle contraction Creatinine is removed from plasma entirely by the kidneys & excreted in urine without reabsorption by the tubules

Answer 23

Does not ⇑ until renal function is impaired Unlike BUN the creatinine level is minimally affected by hepatic function If the value doubles, the renal function has fallen to one-half of its normal state Aminoglycosides, cephalosporins, & nephrotoxic drugs can increase levels

Answer 24

Impaired renal function Urinary tract obstruction Muscle disease, rhabdomyolysis CHF, shock, dehydration

Answer 25

Small stature Decreased muscle mass Inadequate dietary protein Pregnancy

Answer 26

Normal 10:1 Ratios > than 15:1 represent prerenal conditions Ratios < 10:1 occur in persons with liver disease, pregnancy, SIADH & those who receive a low-protein diet or chronic dialysis

Answer 27

Accumulation or elevation of nitrogenous wastes in the blood Pre-renal: elevation of wastes due to pathologic conditions BEFORE it gets to kidney Intrarenal (intrinsic): primary renal disease Post-renal: elevation of wastes due to pathologic conditions of the urinary tract distal to kidneys

Basic Chemistry Flashcards

(51 cards)