| Question | Answer |
| The normal venous pH range | 7.30 - 7.40 |
| What are the 3 major systems that regulate H+ and HCO-3? | The chemical buffer system.
The respiratory system.
The renal system. |
| Which buffer system is the first line of defense & responds w/in a fraction of a second to resist pH changes? | Chemical buffer system. |
| How many minutes does the repiratory system act to acidosis or alkalosis and how does it effect the breathing depth and rate? | It takes 1-3 minutes and decreases the breathing depth and rate. |
| Which system is the body's most effective acid-base balance monitor & regulator? | Renal system |
| How long does it take the renal system to correct abnormal pH concentrations? | 1 day |
| What does the renal system do when extracellular fluids become acidic? | It retains HCO-3 and excretes H+ into the urine, causing the blood pH to increase. |
| Acids & bases are similar to salts thus they can.. | Ionize and dissociate in water & conduct an electrical current. |
| Do acids retain or release hydrogen ions H+? | release |
| Hydrochloric acid (HCl), the acid found in the stomach that works to aid digestion, dissociates into a proton and a chloride ion. What is the equation? | HCl --> H+ Cl- |
| How do the buffers work against sudden and large changes in the pH of body fluids? | releasing hydrogen ions when pH increases and binding hydrogen ions when the pH decrease. |
| Which buffer system plays an extremely important role in maintaining pH homeostasis of the blood. | carbonic acid-bicarbonate buffer system.
Carbonic acid (H2CO3)dissociates reversibly and releases bicarbonate ions (HCO-3)and protons (H+) |
| The carbonic acid-bicarbonate buffer system converts | Strong bases to a weak base (bicarbonate ion).
Strong acids to a weak acid (carbonic acid) |
| The Henderson-Hasselbalch equation | pH=pK+log[HCO3-/H2CO3]
(base/acid) |
| The pK is derived from... | the dissociation constant of the acid portion of the buffer combination |
| Normally the pK ratio is | 6:1 |
| The normal HCO3- to H2CO3 ratio is | 20:1 |
| The primary components of the phosphate buffer system are the | sodium salts of dihydrogen phophate H2PO4-)and monohydrogen phosphate (HPO4-) NaH2PO4 |
| NaH2PO4 - strong or weak base | weak base |
| The phosphate buffer system is only about 1/ <--- as effective as the carbonic acid bicarbonate buffer system in the extracellular fluid. | 1/6 |
| The body's most abundant and influential supply o buffers ___and found in the _____ | protein buffer system and found in the proteins in the plasma and cells |
| Percentage of the buffering power of body fluids is found in the intracellular proteins. | 75% |
| Polymers of acid | proteins |
| amphoteric molecules | protein molecules that have a reversible ability are called |
| A good example of a protein that works as an intracellular buffer | hemoglobin |
| reduced hemoglobin carries a negative charge true or false | true |
| The respiratory system does not respond as fast as the chemical buffer systems but is... | two times the buffering power of all of the chemical buffer systems combined. |
| Under normal conditions, the volume of CO2 eliminated at the lung is equal to the amount of CO2 produced at the tissues. true/false | true |
| When the pH declines, the repiratory system responds by increasing... | the breathing depth and rate. |
| How does the respiratory system respond teh pH rises? | decreases the breathing depth and rate |
| When the volume of CO2 eliminated from the lungs is less than the amount of CO2 produced at the tissue cells, respiratory acidosis is said to exist. true/false | true |
| The renal system can rid the body of acids such as... | phosphoric acids
ulric acids
lactic acids
ketone acids |
| When managing the H+ levels in teh extracellular fluids, the renal system is the only system that can... | regulate alkaline substances in the blood and restore chemical buffers |
| When the extracellular fluids become acidic, the renal system... | retains HCO3- and excretes H+ ions into the urine, causing the blood pH to decrease |
| When the extracellular fluids become alkaline, the renal system retains | H+ and excretes basic substances into the urine, causing the blood pH to decrease |
| Hypoventilation causes the partial pressure of the alvolar carbon dioxide (PAco2) to increase, which in turn causes | Pco2 increase
HCO3- increase
H2CO3 increase
HCO3-:H2CO3 ratio decrease
pH decrease |
| Hyperventilation causes the partial pressure of the alveolar carbon dioxide (PAco2) to increase, which in turn causes | Pco2 decrease
HCO3- decrease
H2CO3 decrease
HCO3-:H2CO3 ratio increase
pH increase |
| Common causes of acute ventilatory failure | chronic obstructive pulmonary
drug overdose
general anesthesia
head trauma
neurologic disorders |
| Renal Compensation
Paco2 of 70 torr
pH 7.30
HCO3- 33 | acute ventilatory failure (with partial renal compensation) |
| If a patient's ventilatory rate suddenly were to increase and cause the patient's Paco2 to increase to 20 torr, what approximate changes would be expected in the pH AND HCO3- levels | Acute alveolar hyperventilation (respiratory alkalosis)
7.60, 20 meq/L |
| common causes of acute alveolar hyperventilation | hypoxia
pain, anxiety, and fever
brain inflammation
stimulant drugs |
| common causes of metabolic acidosis | lactic acidosis (fixed acids)
ketoacidosis (fixed acids)
salicylate intoxication (aspirin overdose)
renal failure
uncontrolled diarrhea |
| plasma concentration of Na+ | 140 |
| plasma concentration of Cl- | 105 |
| plasma concentration of HCO3- | 24 |
| an elevated anion gap is most commonly caused by the accumulation of | fixed acids |
| metabolic acidosis caused by a decreased HCO3- is often called | hyperchloremic metabolic acidosis |
| common causes of metabolic alkalosis | hypokalemia
hypochloremia
gastric suctioning or vomiting
excessive administration of corticosteroids
excessive sodium bicarbonate
diuretic therapy
hypovolemia |
