Exam 5: Renal Function and ABG Flashcards
What is the average glomerular filtration rate in a healthy adult?
120 mL/min when surface area = 1.73
What does the term “glomerular filtration rate” mean?
The volume of plasma that is completely cleared of a solute in a unit of time, expressed in mL/min.
What is the cause of pre-renal failure?
Decreased renal blood flow
What is the cause renal failure?
Direct renal tissue damage
What is the cause of post-renal failure?
Obstruction of urine flow
What hormones are the kidneys responsible for producing?
Renin, prostaglandins, and erythropoeitin.
What does renin do?
produced by kidney and maintains sodium and potassium levels to help control blood pressure
What does erythropoeitin do?
increases rate of RBC production
What do prostaglandins do?
a group of lipids that control processes involving inflammation, blood flow and the formation of blood clots
What are the four blood buffer systems?
Phosphate, protein, hemoglobin, and bicarbonate
What are some causes to perform blood gas testing?
Lung and breathing disorders
Acid-base imbalances
Kidney problems
To monitor/evaluate patient conditions
Which response to changes in the body’s acid/base status is faster- lungs or kidneys? Which one is more potent?
The lung’s response to acid-base changes is much faster, but the kidney is more potent although it is slower response.
What are the four categories of acid-base imbalance that can occur in the body?
Metabolic alkalosis
Metabolic acidosis
Respiratory acidosis
Respiratory alkalosis
What are some causes of metabolic alkalosis?
Excess administration of sodium bicarb (exogenous increase of alkali)
Diuretic therapy (endogenous increase in alkali)
Increased loss of hydrogen ions through vomiting
What are some causes of metabolic acidosis?
Accumulation of fixed acid or loss of extracellular buffers (increase in hydrogen ions or decrease in bicarb)
What are some causes of respiratory acidosis?
Lung disease (accumulation of CO2)
Airway obstruction
Certain drugs that slow respiratory rate
Decreased cardiac output (CHF)
What are some causes of respiratory alkalosis?
Excessive elimination of CO2 by the lungs caused by hyperventilation (hypoxemia)
What is the normal ratio of bicarbonate to carbonic acid in the body? What happens if this ratio changes?
The normal ratio is 20 bicarb for every 1 carbonic acid molecule. If this ratio is off, the pH of the blood will increase/decrease.
How is oxygen delivered to the body’s tissues?
Through hemoglobin with the help of 2,3 diphosphoglycerate to regulate oxygen affinity of hemoglobin
What factors affect the hemoglobin-oxygen dissociation curve?
pH, temperature, pCO2, and 2,3-DPG.
Decreased affinity = increased temp, increased 2,3-DPG, decreased pH, and increased pCO2.
Increased affinity = increased pH, decreased temp, decreased 2,3-DPG, and decreased pCO2.
