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Metabolic compensation

Metabolic and renal compensation for respiratory diseases that can create acidosis revolves around the conservation of bicarbonate ions. In cases of respiratory acidosis, the kidney increases the conservation of bicarbonate and secretion of H + through the exchange mechanism discussed earlier. These processes increase the concentration of bicarbonate in the blood, reestablishing the proper relative concentrations of bicarbonate and carbonic acid. In cases of respiratory alkalosis, the kidneys decrease the production of bicarbonate and reabsorb H + from the tubular fluid. These processes can be limited by the exchange of potassium by the renal cells, which use a K + -H + exchange mechanism (antiporter).

Diagnosing acidosis and alkalosis

Lab tests for pH, CO 2 partial pressure (pCO 2 ), and HCO 3 can identify acidosis and alkalosis, indicating whether the imbalance is respiratory or metabolic, and the extent to which compensatory mechanisms are working. The blood pH value, as shown in [link] , indicates whether the blood is in acidosis, the normal range, or alkalosis. The pCO 2 and total HCO 3 values aid in determining whether the condition is metabolic or respiratory, and whether the patient has been able to compensate for the problem. [link] lists the conditions and laboratory results that can be used to classify these conditions. Metabolic acid-base imbalances typically result from kidney disease, and the respiratory system usually responds to compensate.

Reference values (arterial): pH: 7.35–7.45; pCO 2 : male: 35–48 mm Hg, female: 32–45 mm Hg; total venous bicarbonate: 22–29 mM. N denotes normal; ↑ denotes a rising or increased value; and ↓ denotes a falling or decreased value.
Types of Acidosis and Alkalosis
pH pCO 2 Total HCO 3
Metabolic acidosis N, then ↓
Respiratory acidosis N, then ↑
Metabolic alkalosis N, then↑
Respiratory alkalosis N, then ↓

Metabolic acidosis is problematic, as lower-than-normal amounts of bicarbonate are present in the blood. The pCO 2 would be normal at first, but if compensation has occurred, it would decrease as the body reestablishes the proper ratio of bicarbonate and carbonic acid/CO 2 .

Respiratory acidosis is problematic, as excess CO 2 is present in the blood. Bicarbonate levels would be normal at first, but if compensation has occurred, they would increase in an attempt to reestablish the proper ratio of bicarbonate and carbonic acid/CO 2 .

Alkalosis is characterized by a higher-than-normal pH. Metabolic alkalosis is problematic, as elevated pH and excess bicarbonate are present. The pCO 2 would again be normal at first, but if compensation has occurred, it would increase as the body attempts to reestablish the proper ratios of bicarbonate and carbonic acid/CO 2 .

Respiratory alkalosis is problematic, as CO 2 deficiency is present in the bloodstream. The bicarbonate concentration would be normal at first. When renal compensation occurs, however, the bicarbonate concentration in blood decreases as the kidneys attempt to reestablish the proper ratios of bicarbonate and carbonic acid/CO 2 by eliminating more bicarbonate to bring the pH into the physiological range.

Chapter review

Acidosis and alkalosis describe conditions in which a person's blood is, respectively, too acidic (pH below 7.35) and too alkaline (pH above 7.45). Each of these conditions can be caused either by metabolic problems related to bicarbonate levels or by respiratory problems related to carbonic acid and CO 2 levels. Several compensatory mechanisms allow the body to maintain a normal pH.

Watch this video to see a demonstration of the effect altitude has on blood pH. What effect does high altitude have on blood pH, and why?

Because oxygen is reduced, the respiratory rate increases to accommodate, and hyperventilation removes CO 2 faster than normal, resulting in alkalosis.

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Questions & Answers

Types of living things
Evah Reply
search up "taxonomy"
there are many kingdoms: animal, plants, fungi, and more
a better question would be "What are the various classifications of living organisms?"
learn to ask questions that aren't too vague
what is the largest bone of human?
Aicon Reply
thats a google question
search "largest bone in skeletal system"
The skull
femur in thighs
the diagram of cell membrane
Teboh Reply
***bit.ly/3kfrdfV Link to cell membrane diagram and more info... Remember, you can search the A&P book.
describe diffusion as used in body fluid movement
brenda Reply
how was the movement?
classify joint function with example
James Reply
cytoskeleton diagram
Miriam Reply
two types of cells biological name
eukaryotic and prokaryotic
Difference between extracellular and intracellular
Eli Reply
extra (exit) outside the cell, intra inside the cell
extracellular is 1/3 of total body water...intracellular 2/3 of total body water
what is culture?
is the way of life of people
He meant in the context of biology...as in "tissue culture".
what does depolarization mean...in terms of the cardiovascular system?
depolarization means contraction
Depolarization, in the context of nerve and muscle tissue, is the decrease in membrane potential (the separation of charge between the extracellular and intracellular compartments). Basically, the charge in the cell becomes more positive when depolarization occurs.
In fact, the word 'polarize' used to mean dividing into extremes or opposite sides. The opposite is true for 'depolarize'
intracellular fluid is the fluid compartment of the body consisting of all water present within the cell...while extracellular fluid is water present out of the cell
Why apoptosis is important?
Duchess Reply
name the body organ which helps in the oxygenation of body.
Eli Reply
respiratory system (lungs) brings in oxygen...cardiovascular system (blood) circulate it
the heart
Mpho explain
cells... tissues...organs
Angel Reply
...organ system...organism...species...population...
connection between respiratory and circulatory system
Philip Reply
what's respiratory system
what is the site of CHON synthesis?
send them boi
dont send via email...use google drive
Which major organ lies deep to the right hypochondriac region?
Biswajit Reply
deep as in most posterior kidney, or deep as in inferior small intestine?
what is the weakest muscle in the body?
zharla Reply
Connective tissues composed with the blood
blood cell
Why is left bronchi narrow?
what is the most widely distributed connective tissue in the body?
Aila Reply

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