Acid Base Homeostasis and Imbalances Flashcards
memorize labs for
pH
7.35 to 7.45
memorize labs for paCo2
35-45–adults
memorize labs for
PaO2
80 to 100 mmHg
memorize labs for
HCO3
22-26 mEq/L
what do the PaCO2 and the HCO3- indicate for acid base balance
PaCO2 is used to determine how much carbon dioxide is in your blood.
HCO3 is a buffer, if you are building it up you have alkalosis, if you are losing it you have acidosis
describe the role of the bicarbonate buffer system, including the chemical equation accelerated by carbonic anhydrase
The role of all the buffer systems, including the bicarbonate buffer system is to protect the pH of body fluids. They act immediately to combine with excess acids or bases and prevent large changes in pH form occurring during the time it takes for the respiratory and renal mechanisms.
HCl + NaHCO3 X H2CO3 + NaCl
CO2 + H2O ↔ H2CO3–catalyzed by carbonic anhydrase
how does the respiratory system regulate carbonic acid (carbon dioxide)
the respiratory system regulates carbonic acid levels in the blood are controlled by the expiration of CO2 through the lungs.
how do the lungs compensate for the buildup of metabolic acids?
they increase the respiratory rate
how do the kidneys regulate bicarbonate ions?
the kidneys regulate bicarbonate ions by reabsorbing HCO3- that is filtered in the glomerulus
producing new HCO3- that is released back into the blood
how do the kidneys compensate for buildup of carbonic acid in the blood?
increased urinary excretion and reabsorption of HCO3-
for metabolic acidosis, list clinical signs and explain how circulatory shock, tissue anoxia, and diarrhea would cause this.
clinical signs
clinical signs: blood pH decreased, HCO3- (primary) decreased, PCO2 (compensatory) decreased
GI: anorexia, nausea and vomiting, abdominal pain
Neural Function: weakness, lethargy, general malaise, confusion, stupor, coma, depression of vital functions.
cardiovascular function: peripheral vasodilation, decreased heart rate, cardiac arrhythmias.
Skin: warm and flushed
Skeletal System: bone disease
Signs of compensation: increased rate and depth of respiration (Kussmaul breathing) hyperkalemia acid urine increase ammonia in urine.
for metabolic acidosis, list clinical signs and explain how circulatory shock, tissue anoxia, and diarrhea would cause this.
clinical signs
clinical signs: blood pH decreased, HCO3- (primary) decreased, PCO2 (compensatory) decreased
GI: anorexia, nausea and vomiting, abdominal pain
Neural Function: weakness, lethargy, general malaise, confusion, stupor, coma, depression of vital functions.
cardiovascular function: peripheral vasodilation, decreased heart rate, cardiac arrhythmias.
Skin: warm and flushed
Skeletal System: bone disease
Signs of compensation: increased rate and depth of respiration (Kussmaul breathing) hyperkalemia acid urine increase ammonia in urine.
for metabolic acidosis, list clinical signs and explain how circulatory shock, tissue anoxia, and diarrhea would cause this.
circulatory shock
how would circulatory shock cause metabolic acidosis?
In the trauma setting, acidosis is often a consequence of hypoperfusion due to hemorrhagic shock and is metabolic in nature. Without oxygen supply, peripheral tissues resort to anaerobic metabolism for energy production, thereby increasing the production of lactic acid.
state and explain the compensatory response for metabolic acidosis
increased rate and depth of respirations: respiratory system compensating for decrease in pH by increasing ventilation to reduce PCO2 by deep and rapid respirations. Someone breathes as they have been running when they aren’t.
hyperkalemia: acidosis causes potassium to move from cells to extracellular fluid (plasma) in exchange for hydrogen ions, thus hyperkalemia happens
acid urine: if there is too much acid floating around, the body is going to try to excrete it in the urine.
increased ammonia in urine: Metabolic acidosis stimulates ammonia production and transport by renal epithelial cells.
describe how respiratory acidosis develops in people with COPD?
if they receive o2 therapy that is at a level significant enough to raise their PO2 to a level that produces a decrease in ventilation. Bc of the adaptation to the disease, a decrease in the PO2 becomes the major stimulus for respiration.
