C4 - Section 3. Disorders of Acid-Base balance Flashcards
Normal arterial blood pH is restricted to a very narrow range of (?).
7.35 to 7.45
A person who has a blood pH below 7.35 is considered to be in acidosis (actually, (?) because blood is not truly acidic until its pH drops below 7), and a continuous blood pH below 7.0 can be fatal.
“physiological acidosis,”
Acidosis has several symptoms, including (?), and the individual can become (?).
headache and confusion
lethargic and easily fatigued
A person who has a blood pH above 7.45 is considered to be in (?), and a pH above 7.8 is fatal.
alkalosis
Some symptoms of alkalosis include (?).
cognitive impairment (which can progress to unconsciousness), tingling or numbness in the extremities, muscle twitching and spasm, and nausea and vomiting
Both acidosis and alkalosis can be caused by either (?).
metabolic or respiratory disorders
As discussed earlier in this chapter, the concentration of (?) in the blood is dependent on the level of CO2 in the body and the amount of CO2 gas exhaled through the lungs.
carbonic acid
Thus, the respiratory contribution to acid-base balance is usually discussed in terms of (?) (rather than of carbonic acid).
CO2
Remember that a molecule of carbonic acid is lost for every molecule of (?), and a molecule of carbonic acid is formed for every molecule of (?).
CO2 exhaled
CO2 retained
SYMPTOMS OF ACIDOSIS
Central Nervous System
Headache
Sleepiness
Confusion
Loss of consciousness
Coma
SYMPTOMS OF ACIDOSIS
Respiratory System
shortness of breath
Coughing
SYMPTOMS OF ACIDOSIS
Heart
Arrhythmia
Increased heart rate
SYMPTOMS OF ACIDOSIS
Muscular Svstem
Seizures
Weakness
SYMPTOMS OF ACIDOSIS
Digestive System
Nausea
Vomiting
Diarrhea
SYMPTOMS OF ALKALOSIS
Central Nervous System
confusion
Light-headedness
Stupor
Coma
SYMPTOMS OF ALKALOSIS
Peripheral Nervous System
Heart
Arrhythmia
Numbness or tingling in the face, hands, or feet
SYMPTOMS OF ALKALOSIS
Muscular Svstem
Seizures
Weakness
Muscular System
Twitching
Prolonged spasms
SYMPTOMS OF ALKALOSIS
Digestive System
Nausea
Vomiting
Diarrhea
Digestive System
Nausea
Vomiting
Normal Values:
pH:
CO2:
Bicarbonate:
7.35 -7.45
35 - 45 mmHg
22 - 26%
Primary Bicarbonate Deficiency
Metabolic Acidosis
Occurs when the blood is too acidic (pH below 7.35) due to too little bicarbonate, a condition called primary bicarbonate deficiency.
Metabolic Acidosis
At the normal pH of 7.40, the ratio of bicarbonate to carbonic acid buffer is 20:1.
Metabolic Acidosis
If a person’s blood pH drops below 7.35, then he or she is in metabolic acidosis.
Metabolic Acidosis
The most common cause of metabolic acidosis is the presence of organic acids or excessive ketones in the blood.
Metabolic Acidosis
Primary Bicarbonate Excess
Metabolic Alkalosis
Is the opposite of metabolic acidosis.
Metabolic Alkalosis
It occurs when the blood is too alkaline (pH above 7.45) due to too much bicarbonate (called primary bicarbonate excess).
Metabolic Alkalosis
A transient excess of bicarbonate in the blood can follow ingestion of excessive amounts of bicarbonate, citrate, or antacids for conditions such as stomach acid reflux— known as heartburn.
Metabolic Alkalosis
Cushing’s disease, which is the chronic hypersecretion of adrenocorticotrophic hormone (ACTH) by the anterior pituitary gland, can cause chronic metabolic alkalosis.
Metabolic Alkalosis
The oversecretion of ACTH results in elevated aldosterone levels and an increased loss of potassium by urinary excretion.
Metabolic Alkalosis
Other causes of metabolic alkalosis include the loss of hydrochloric acid from the stomach through vomiting, potassium depletion due to the use of diuretics for hypertension, and the excessive use of laxatives.
Metabolic Alkalosis
Primary Carbonic acid/ CO2 Excess
Respiratory Acidosis
Occurs when the blood is overly acidic due to an excess of carbonic acid, resulting from too much CO2 in the blood.
Respiratory Acidosis
Respiratory acidosis can result from anything that interferes with respiration, such as pneumonia, emphysema, or congestive heart failure.
Respiratory Acidosis
Primary Carbonic acid/CO2 Deficiency
Respiratory Alkalosis
Occurs when the blood is overly alkaline due to a deficiency in carbonic acid and CO2 levels in the blood.
Respiratory Alkalosis
This condition usually occurs when too much CO2 is exhaled from the lungs, as occurs in hyperventilation, which is breathing that is deeper or more frequent than normal.
Respiratory Alkalosis
An elevated respiratory rate leading to hyperventilation can be due to extreme emotional upset or fear, fever, infections, hypoxia, or abnormally high levels of catecholamines, such as epinephrine and norepinephrine.
Respiratory Alkalosis
Surprisingly, aspirin overdose—salicylate toxicity—can result in respiratory alkalosis as the body tries to compensate for initial acidosis.
Respiratory Alkalosis
