Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
DU PA Surg Flui/elec
Duke PA Surgery Fluids and electrolytes
| Question | Answer |
|---|---|
| total body water accounts for __% or more of body weight | 60 |
| water is contained primarily in | skeletal muscle |
| intrecellular water composes __ of total body water | 2/3 |
| extracellular water composes __ of total body water | 1/3 |
| interstitial water accounts for __% of extracellular water | 75 |
| intravascular water or plasma water, constitutes __% of extracellular water volume or 4-7% of body weight | 25 |
| in the intracellular compartment __ is the dominant cation | potassium |
| in the interstitial and intravascular compartments __ is the dominant cation | sodium |
| electrical neutrality is maintained by a balanced amount of | chloride and bicarb ions |
| to maintain electrical neutrality, the negative charge on plasma albumin requires an increase in | plasma cations, mostly sodium |
| the redistribution of ions across the semipermeable membrane is called the | Donnan effect |
| refers to the number of particles dissolved in a solution | olsmolarity |
| is calculated by considering only the concentration of impermeable solutes in solution | tonicity |
| ___ is an enzyme released by the juxtaglomerular cells of the afferent arteriole in response to a decrease in arterial blood pressure, hypovolemia, hyponatremia, and increased beta-adrenergic activity | renin |
| Renin converts angiotensinogen to angiotensin I which is then converted to angiotensin II in the pulmonary circulation by | Angiotensin-converting enzyme (ACE) |
| Angiotensin releases ___ from the renal cortex | aldosterone |
| Aldosterone acts on the distal tubules and collecting ducts to | increase sodium reabsorption and potassium excretion |
| angiotensin increases | cardiac output and peripheral resistance |
| normally and adult ingests __L of water per day | 2-3 |
| ___ mL/day is the minimal volume required to allow solute excretion | 300 |
| chronic volume depletion is manifested by | oliguria, loss of skin turgor, orthostatic hypotension, low urine sodium concentration, BUN/creatinine ratio that exceeds 15:1. |
| Acute volume losses are manifested by | hypotension, tachycardia, and tachypnea |
| normal dietary salt intake is __g/day | 6-15 |
| hypernatremia is defined as a serum sodium concentration that exceeds __ mEq/L | 150 |
| hypernatremia is always accompanied by | hyperosmolarity |
| any net gain in sodium will increase the | extracellular fluid and trigger transmembrane water shifts leading to cellular dehydration |
| hypernatremia may be due to | excessive salt intake, excessive water loss, reduced salt excretion, reduced water intake |
| ordinarily the hyperosmolar state of hypernatremia will drive thirst and | ADH release |
| in surgical patients, hypernatremia may result from the administration of __ which lead to free water depletion | loop diuretics |
| neurologic symptoms of hypernatremia | malaise, lethargy, vomiting, general seizures, and coma |
| rapid sodium increases will lead to | cerebral dehydration |
| therapy for hypernatremia is directed first at | restoring volume with isotonic saline solution |
| once intravascular volume is restored in hypernatremia, it is further corrected by administration of | free water in the form of D5W |
| hyponatremia is defined as a serum sodium concentration that is less than __mEq/L | 135 |
| hyponatremia may be caused by | excessive water intake, impaired renal water excretion, and loss of renal diluting capacity |
| symptoms of hyponatremia are | mostly neurologic and are due to cellular swelling |
| cellular swelling in hyponatremia is induced by | extracellular fluid hypo-osmolality |
| in hyponatremia cerebral swelling causes | lethargy, confusion, vomiting, seizures, and coma |
| patients in this group often have edema | hypervolemic hyponatremia |
| causes include renal failure, CHF, COPD, severe liver disease | hypervolemic hyponatremia |
| the most common cause of normovolemic hyponatremia is | the syndrome of inappropriate secretion of ADH (SIADH) |
| SIADH is seen in patients with | central nervous system pathology such as stroke or injury, and in pulmonary conditions including tuberculosis and cancer |
| pateints with hypovolemic hyponatremia have | renal or extrarenal losses of sodium that exceed water losses |
| in hypervolemic hyponatremic patients the treatment includes | volume restriction and loop diuretics |
| patients with SIADH usually respond to | fluid restriction |
| in hypovolemic hyponatremic patients treatment includes | salt and water replacement |
| in asymptomatic patients, hyponatremia should be treated | slowly |
| with symptomatic hyponatremia, current recommendations are to increase the serum sodium concentration no faster than __mEq/L/hr | 0.5 |
| in patients with stupor, coma, or other severe neurologic symptoms from hyponatremia __ is used | hypertonic (3% NaCl) solution |
| most of the bodies potassium is found in | skeletal muscle |
| the normal plasma potassium concentration is __ mEq/L | 3.5-5 |
| the usually dietary intake of potassium is __ mEq/kg | 1-1.5 |
| hyperkalemia is defined as a serum potassium concentration greater than __ mEq/L | 5.5 |
| hyperkalemia can result from | renal or adrenal insufficiency, metabolic acidosis, or iatrogenic causes |
| the most common cause of metabolic alkalosis in surgical patients is | nasogastric losses or vomiting |
| the peritoneal surfaces represent __% fo body surface area | 50 |
| during laparotomy, the expected evaporative fluid loss from exposed peritoneum is __ mL/kg/hr | 10 |
| hyperphosphatemia may result from | rhabdomyolysis due to muscle ischemia or crush injury |
| the stress response to surgery results in the release of | glucagon, aldosterone, cortisol, and antidiuretic hormone |
| hyperkalemia occurs with __ due to transcellular exchange of K+ and H+ | metabolic acidosis |
| extrarenal causes of hyperkalemia | intravascular hemolysis, rhabdomyolysis, seizures, and sever GI bleed |
| iatrogenic causes of hyperkalemia | NSAIDs, ACEIs |
| the earliest EKG abnormality of hyperkalemia is | peaking of T waves |
| as plasma potassium increases | PR intervals become prolonged, and the RR interval increases |
| further increases in K+ concentration are associated with | loss of P waves and widening of QRS |
| the final effect of hyperkalemia on the heart is | complete heart block, v-tach, then asystole |
| extracardiac symptoms of hyperkalemia | paresthesias, flaccid paralysis, ileus |
| to reverse cardiac toxicity in hyperkalemia __ should be administered | calcium gluconate |
| in hyperkalemia the response to calcium salt therapy occurs in | 1-5 minutes and lasts 30 minutes |
| in hyperkalemia concurrent treatment with __ moves K+ into cells | insulin or sodium bicarbonate |
| potassium can be removed by treatment with the cation-exchange resin | kayexalate (50-100 g as enema) or 40g orally with sorbitol |
| the most effective method of removing potassium is | dialysis |
| when using ___ to treat hyperkalemia, the onset of action is slow, and the effects last 4-6 hours | kayexalate |
| hypkalemia is defined as a serum potassium concentration that is less than __mEq/L | 3.5 |
| hypokalemia is a common problem in surgical patients and is usually caused by | GI losses from vomiting, diarrhea, or fistula, and the use of diuretics |
| ___ often coexists with hypokalemia | metabolic alkalosis |
| metabolic acidosis decreases | renal potassium conservation |
| EKG may show ___ in hypokalemia | t-wave flattening/inversion, diminished QRS voltage, and U waves |
| in patients taking digoxin __ can provoke life threatening arrhythmias | hypokalemia |
| potassium should be given __ unless the hypokalemia is severe (<2.5 mEq/L) | orally |
| the serum ionized calcium concentration is maintained within a narrow range of ___ mg/dL | 4.4-5.3 |
| a reduction in serum calcium stimulates a release of | parathyroid hormone |
| parathyroid hormone increases | calcium reabsorption from bone |
| PTH enhances | calcium reabsorption from the distal convoluted tubule |
| PTH stimulates | formation of the active metabolite of vitamin D that increases gut absorption of elemental calcium |
| hypercalcemia is defined as ionized calcium concentration that exceeds __ mg/dL | 5.3 |
| although hypercalcemia is most frequently associated with hyperparathyroidism in surgical patients, it is also commonly associated with | cancer |
| other causes of enhanced bone reabsorption | Paget's disease, pheochromocytoma, hyperthyroidism, and use of thiazide diuretics |
| cardiovascular manifestations of hypercalcemia include | arrhythmias and a shortened QT interval |
| GI effects of hypercalcemia | anorexia, constipation, pancreatitis, and hyperacidity |
| the most common renal defect associated with hypercalcemia is | polyuria |
| if hyperparathyroidism is the cause of hypercalcemia the best treatment is | surgery |
| initial supportive therapy for hypercalcemia includes | saline diuresis and furosamide |
| __ reduces bone reabsorption and has an immediate effect | calcitonin |
| ___ are highly effective inhibitors of osteoclast activity but have a delayed onset of 2-3 days | biphosphonates |
| hypocalcemia is defined as an ionized calcium concentration of less than __ mg/dL | 4.4 |
| hypocalcemia is seen in | parathyroid or thyroid surgery, sever pancreatitis, magnesium deficiency, and after massive blood transfusion |
| neuromuscular findings in hypocalcemia include | paresthesias, muscular spasms, seizures, tetany, and weakness |
| cardiovascular symptoms of hypocalcemia include | heart block, arrhythmias, bradycardia, and refractory hypotension |
| EKG findings with hypocalcemia | prolongation of the QT interval and T-wave inversion |
| in patients with symptomatic or severe hypocalcemia ___ is indicated | IV calcium therapy |
| fixed acids | citric, pyruvic, sulfuric, phosphoric, acetoacetic |
| ___ are the main buffers in the body | bicarbonate and hemoglobin |
| in body fluids CO2 combines with water to form | carbonic anhydrase |
| kidneys can compensate for the buffer lost during CO2 excretion by the lungs with | bicarbonate reabsorption and ammonia production |
| metabolic acidosis is present when pH is less than 7.35 and plasma bicarbonate is less than __ mEq/L | 22 |
| in spontaneously breathing patients the increase in hydrogen ion concentration should stimulate __ thereby decreasing PCO2 | compensatory increase in ventilatory rate |
| the presence or absence of an ___ helps to categorized metabolic acidoses | anion gap |
| the anion gap is calculated as the difference between the concentrations of | the major extracellular cation sodium and the major anions chloride plus bicarbonate |
| a normal anion gap is __mEq/L | 8-12 |
| the causes of anion gap acidosis can be remembered by the mnemonic | Dr. Maples |
| Dr. Maples stands for | Diabetic Ketoacidosis, Renal failure, methanol, alcohol, paraldehyde, lactic acidosis, ethylene glycol, salicylates |
| in trauma patients metabolic acidosis must be assumed to be due to | blood loss (hypoperfusion and tissue hypoxia) |
| non-anion gap metabolic acidosis is characterized by loss of | buffer base |
| common causes of non-anion gap metabolic acidosis | GI tract loss, renal tubular acidosis, Addison's disease, total parenteral nutrition, and use of carbonic anhydrase inhibitors |
| therapy with ___ is reserved for those in severe metabolic acidosis (<7.2), and in those with life threatening ventricular arrhythmias, hemodynamic instability, inadequate compensatory response | sodium bicarbonate |
| explained by the inability of the kidney to excrete excess bicarbonate or to retain hydrogen ion | metabolic alkalosis |
| metabolic alkalosis is usually accompanied by | respiratory compensation |
| respiratory acidosis is present when the pH is low and the PCO2 is | elevated |
| respiratory acidosis is due to | ineffective alveolar ventilation |
| treatment of respiratory acidosis may require | intubation and mechanical ventilation |
| respiratory alkalosis is present when the pH is high and the PCO2 is | low |
| caused by alveolar hyperventilation | respiratory alkalosis |
| in the surgical pateint respiratory alkalosis may be caused by | hypoxia, central nervous system lesion, pain, hepatic encephalopathy, and mechanical ventilation |
| in acute respiratory alkalosis renal compensation is | minimal |
| in chronic respiratory alkalosis renal compensation is by | a decrease in hydrogen ion excretion |
| most patients with respiratory alkalosis are | asymptomatic |
| hyperventilation is particularly dangerous in patients with subarachnoid hemorrhage because it ecacerbates | vasospasm |
Created by:
bwyche
Popular Medical sets