Acid Base Balance and Pathophysiology-Exam 2: Ch.3 Flashcards
Type of kidney buffers
bicarb, ammonia, phosphate
Causes of metabolic alkalosis
prolonged vomiting, nasogastric suction; NaHCO3 ingestion, diuretic therapy without K
-with hyperaldosteronism, sodium retention and loss of hydrogen and potassium ions
Causes of respiratory acidosis
Causes: COPD, asthma, obesity
Manifestations: increased resp .rate, decreased sensorium, GI distress (n/v/d), and ventricular arrhythmias
Causes of respiratory alkalosis
Causes: anxiety, tumor, fever, pain, trauma, severe anemia
Manifestations: decreased resp. rate with increased depth, reflect loss/decrease in electrolyte (muscle cramps, weakness, paresthesias), atrial tachycardia
Role of kidneys in maintaining acid base homeostasis
The kidneys have two main ways to maintain acid-base balance - their cells reabsorb bicarbonate HCO3− from the urine back to the blood and they secrete hydrogen H+ ions into the urine.
By adjusting the amounts reabsorbed and secreted, they balance the bloodstream’s pH.
Acidemia
a state in which the pH of arterial blood is less than 7.35.
Alkaemia
a state in which the pH of arterial blood is greater than 7.45.
Acidosis
a systemic increase in hydrogen ion concentration or loss of base.
Define pH
Each unit of change represents a tenfold change in acidity or alkalinity and that is the negative logarithm of the effective hydrogen‐ion concentration in moles H+ ions per liter of the solution. Pure water is 1x10e(‐7) moles H+ ions per liter, so the pH value of pure water is 7 .
Metabolic acidosis clinical mafnifestations
- kussmal respirations
- early symptoms is headache and lethargy
- anorexia, nausea, vomiting, diarrhea, and abd discomfort
- ketoacidosis
- deep respirations indicate resp. compensation
- if acidosis progresses it can lead to coma then ultimately death
Decreased blood pH leads to
- decreased myocardial contraction, causing decreased bp
- arterial vasodilation
- pH below 7.15 to 7.2, the effect of acidemia is prominent
Clinical Manifestations of metabolic alkalosis
- irritated, twitching, and confused
- n/v/d
- some may have severe cramping, paresthesia, or even tetany, but in other with similar electrolytes, they have no s/s
- hyperactive reflexes
- tetany
- confusion/convulsions
- cardiovascular abnormalities due to hypokalemia
- atrial tachycardia
Electrolytes effected by metabolic alkalosis
potassium, calcium, and magnesium
Compensatory process for metabolic acidosis
hyperventilation
Compensatory process for metabolic alkalosis
hypoventilation
Compensatory process for respiratory acidosis
renal HCO3-retention
Compensatory process for respiratory alkalosis
renal HCO3- excretion
Acidosis
systemic increase in hydrogen ion concentration or a loss of base
pH <7.35
Alkalosis
systemic decrease in hydrogen ion concentration or an excess of base
pH >7.45
Hydrogen ion is necessary for:
for maintaining membrane integrity, enzyme activity.
Inside cell
potassium is high
sodium is low
Outside of cell
potassium is low
sodium is high
calcium high
What is the reciprocal K+ exchange in alkalosis
- H+ moves extracellularly
- K+ moves intracellularly
What is the reciprocal K+ exchange in acidosis
- H+ moves intracellularly
- K+ moves extracellularly
Normal pH is
7.35 (slightly alkaline….pH of water is 7 which is neutral)
Buffer
a substance capable in solution of neutralizing both acids and bases and thereby maintaining the original acidity or basicity of the solution.
Buffering
responding to changes and maintaining the original acid‐base status.
pH
Each unit of change represents a tenfold change in acidity or alkalinity and that is the negative logarithm of the effective hydrogen‐ion concentration in moles H+ ions per liter of the solution. Pure water is 1x10e(‐7) moles H+ ions per liter, so the pH value of pure water is 7.
Importance of hydrogen ion
necessary to maintain membrane integrity, enzyme activity. Most pathologic conditions disturb acid‐base balance, and the degree of severity may be more harmful than the disease process.
How do kidneys help control acid base balance
by excreting hydrogen ions and generating bicarbonate that helps maintain blood plasma pH within a normal range. Protein buffer systems work predominantly inside cells. Lungs exhale CO2 from the body and adjust the blood pH.yh7
Buffers
- protein buffer
- phosphate buffer
- ammonia buffer
- bicarbonate-carbonic acid buffer
What kind of charge do proteins have
negative
Where to proteins mainly function
intracellular buffer system
Plasma buffers
- hemoglobin
- phosphate
- bicarb-carbonic acid
Intracellular buffers
- protein
- phosphate
- other ions (ex: K+)
Kidney buffers
- bicarb
- ammonica
- phosphate
Causes of metabolic acidosis
cancer, carbon monoxide poisoning, exercise, liver failure, hypoglycemia
causes of metabolic alkalosis
diuretics, antacids, certain laxatives, steroids, baking soda