acidosis

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Related to bicarbonate ion: hydrogen carbonate, Carbonic anhydrase, Hco3

acidosis

 [as″ĭ-do´sis]
1. the accumulation of acid and hydrogen ions or depletion of the alkaline reserve (bicarbonate content) in the blood and body tissues, resulting in a decrease in pH.
2. a pathologic condition resulting from this process, characterized by increase in hydrogen ion concentration (decrease in pH). The optimal acid-base balance is maintained by chemical buffers, biologic activities of the cells, and effective functioning of the lungs and kidneys. The opposite of acidosis is alkalosis. adj., adj acidot´ic.

Acidosis usually occurs secondary to some underlying disease process; the two major types, distinguished according to cause, are metabolic acidosis and respiratory acidosis (see accompanying table). In mild cases the symptoms may be overlooked; in severe cases symptoms are more obvious and may include muscle twitching, involuntary movement, cardiac arrhythmias, disorientation, and coma.

In general, treatment consists of intravenous or oral administration of sodium bicarbonate or sodium lactate solutions and correction of the underlying cause of the imbalance. Many cases of severe acidosis can be prevented by careful monitoring of patients whose primary illness predisposes them to respiratory problems or metabolic derangements that can cause increased levels of acidity or decreased bicarbonate levels. Such care includes effective teaching of self-care to the diabetic so that the disease remains under control. Patients receiving intravenous therapy, especially those having a fluid deficit, and those with biliary or intestinal intubation should be watched closely for early signs of acidosis. Others predisposed to acidosis are patients with shock, hyperthyroidism, advanced circulatory failure, renal failure, respiratory disorders, or liver disease.
compensated acidosis a condition in which the compensatory mechanisms have returned the pH toward normal.
diabetic acidosis a metabolic acidosis produced by accumulation of ketones in uncontrolled diabetes mellitus.
hypercapnic acidosis respiratory acidosis.
hyperchloremic acidosis renal tubular acidosis.
lactic acidosis a metabolic acidosis occurring as a result of excess lactic acid in the blood, due to conditions causing impaired cell respiration. It occurs most commonly in disorders in which oxygen is inadequately delivered to tissues, such as shock, septicemia, or extreme hypoxemia, but it can also result from exogenous or endogenous metabolic defects. Initially manifesting as hyperventilation, it progresses to mental confusion and coma.
metabolic acidosis any of the types of acidosis resulting from accumulation in the blood of keto acids (derived from fat metabolism) at the expense of bicarbonate; this diminishes the body's ability to neutralize acids. This type is contrasted with respiratory acidosis. It occurs when there is either an acid gain (as in diabetic ketoacidosis, lactic acidosis, poisoning, or failure of the renal tubules to reabsorb bicarbonate) or a bicarbonate loss (as in diarrhea or a gastrointestinal fistula).

The symptoms of metabolic acidosis include weakness, malaise, and headache. As the acid level goes up these symptoms progress to stupor, unconsciousness, coma, and death. The breath may have a fruity odor owing to the presence of acetone, and the patient may experience vomiting and diarrhea. Loss of fluids can deplete body fluid content and aggravate the acidosis. Hyperventilation may occur as a result of stimulation of the hypothalamus. blood gas analysis will reveal a lowered pH and an elevated PaCO2. (See accompanying table.)
Treatment and Patient Care. Treatment of metabolic acidosis is primarily concerned with control of the underlying causes. Diabetic ketoacidosis may be corrected by the administration of insulin and fluids. In acute renal failure the patient requires dialysis, and in chronic uremic acidosis the condition is controlled by restricting sodium intake and buffering with bicarbonate. The patient's vital signs should be checked frequently to assess the progress of compensation. A rising pulse rate and a drop in blood pressure frequently occur as a result of hypovolemia in the diabetic-acidotic patient, and cardiac arrhythmias can be caused by increased calcium levels in the blood. A careful recording of intake and output provides a means of determining the kidneys' ability to regulate the acid-base balance. Safety measures to avoid injury during involuntary muscular contractions should be carried out. (See also convulsions.) Nursing measures to relieve discomfort from vomiting and to avoid the hazards of aspiration of vomitus are required. Education of the patient and family in the prevention of acute episodes of metabolic acidosis, particularly diabetic ketoacidosis, is of primary importance.
renal tubular acidosis (RTA) a metabolic acidosis resulting from impairment of the reabsorption of bicarbonate by the renal tubules, characterized by low plasma bicarbonate and high plasma chloride; the urine is alkaline.
respiratory acidosis acidosis resulting from ventilatory impairment and subsequent retention of carbon dioxide, in contrast to metabolic acidosis. The respiratory system has an important role in maintaining acid-base balance. In response to an increase in the hydrogen ion concentration in body fluids, the respiratory rate increases, causing more carbon dioxide to be released from the lung. When either an acute obstruction of the airways or a chronic condition involving the organs of respiration causes interference with the exhalation of the carbon dioxide produced by metabolic activity, carbon dioxide accumulates in the blood and unites with water to form carbonic acid.

Acute respiratory acidosis occurs when there is a relatively sudden malfunction of respiratory activities, as in upper airway obstruction, acute infections and inflammation of the lung and bronchial tissues, and pulmonary edema. In acute respiratory acidosis the compensatory chemical buffer systems are of limited benefit in restoring the acid-base balance because they depend on normal blood circulation and tissue perfusion for optimal effect. The physiologic regulators, the lungs and kidneys, are of little help because the lungs are malfunctioning and the kidneys require more time to compensate than the acute condition permits.

Chronic respiratory acidosis results from gradual and irreversible loss of ventilatory function, as in chronic obstructive pulmonary disease (COPD). Although the patient in this condition does have an increased retention of CO2, there is time for the kidneys to compensate by retaining bicarbonate and thereby maintaining a pH within tolerable limits. If, however, even a minor respiratory infection develops, the patient is subject to a rapidly developing state of acute acidosis because the lungs cannot be depended upon to remove more than a minimal amount of CO2.
Treatment and Patient Care. The initial treatment for acute respiratory acidosis is to establish an airway immediately and maintain adequate ventilation and hydration. Acute cases may require the use of an endotracheal tube or tracheostomy tube. Some form of intermittent positive pressure breathing is applied through a machine-driven ventilator, essentially to force adequate O2 delivery and concomitant CO2 removal from the lungs, thereby avoiding further rises in CO2 levels to the point that CO2 narcosis will develop. Beyond a certain point the respiratory center may cease responding to the higher CO2 levels, and breathing will stop abruptly. Drugs that further depress the respiratory center (narcotics, hypnotics, and tranquilizers) must be avoided. Patients in the acute stage are watched for cessation of breathing and cardiac arrest. cardiopulmonary resuscitation may be required to revive the patient.

It is recommended that oxygen administration be limited in patients with chronic obstructive pulmonary disease (COPD). In COPD the stimulus to breathe is a hypoxic state, therefore administration of high concentrations of O2 will remove this needed stimulus. The rate of oxygen flow should be closely correlated with blood gas studies. In patients with acute lung diseases the stimulus to breathe is still dependent on CO2 concentrations, so that O2 can be supplied without fear of inhibiting the stimulus to breathe.

Measures that facilitate breathing are essential to patient care during respiratory acidosis. Frequent turning, coughing, and deep breathing exercises to encourage oxygen–carbon dioxide exchange are beneficial, as is suctioning when needed to remove secretions obstructing the airway. postural drainage, unless contraindicated by the patient's condition, may be effective in promoting adequate ventilation.
starvation acidosis a metabolic acidosis due to accumulation of ketones following a severe caloric deficit.

ac·i·do·sis

(as'i-dō'sis),
A pathologic state characterized by an increase in the concentration of hydrogen ions in the arterial blood above the normal level, 40 nmol/L, or pH less than 7.4; may be caused by an accumulation of carbon dioxide or acidic products of metabolism or by a decrease in the concentration of alkaline compounds.
[acid + G. -ōsis, condition]

acidosis

/ac·i·do·sis/ (as″ĭ-do´sis)
1. the accumulation of acid and hydrogen ions or depletion of the alkaline reserve (bicarbonate content) in the blood and body tissues, decreasing the pH.
2. a pathologic condition resulting from this process. Cf. alkalosis. acidot´ic

compensated acidosis  a condition in which the compensatory mechanisms have returned the pH toward normal.
diabetic acidosis  metabolic acidosis produced by accumulation of ketones in uncontrolled diabetes mellitus.
hypercapnic acidosis  respiratory a.
hyperchloremic acidosis  metabolic acidosis accompanied by elevated plasma chloride.
lactic acidosis  a metabolic acidosis occurring as a result of excess lactic acid in the blood, due to conditions causing impaired cellular respiration.
metabolic acidosis , nonrespiratory acidosis a disturbance in which the acid-base status shifts toward the acid because of loss of base or retention of noncarbonic, or fixed (nonvolatile), acids.
renal hyperchloremia acidosis , renal tubular acidosis (RTA) metabolic acidosis resulting from impairment of renal function.
respiratory acidosis  acidosis due to excess retention of carbon dioxide in the body.
starvation acidosis  metabolic acidosis due to accumulation of ketone bodies which may accompany a caloric deficit.
uremic acidosis  metabolic acidosis seen in chronic renal disease when the ability to excrete acid is decreased.

acidosis

(ăs′ĭ-dō′sĭs)
n.
1. Abnormally high acidity of the blood and body tissues caused by a deficiency of bicarbonates or an excess of acids other than carbonic acid. It can result from any of various acute or chronic disorders or from the ingestion of certain drugs and toxins. Also called metabolic acidosis.
2. Abnormally high acidity of the blood and body tissues caused by an excess of carbon dioxide due to hypoventilation. Also called respiratory acidosis.

ac′i·dot′ic (-dŏt′ĭk) adj.

acidosis

[as′idō′sis]
Etymology: L, acidus + Gk, osis, condition
an abnormal increase in the hydrogen ion concentration in the blood, resulting from an accumulation of an acid or the loss of a base. It is indicated by a blood pH below the normal range (7.35 to 7.45). The various forms of acidosis are named for their cause; for example, renal tubular acidosis results from failure of the kidney to secrete hydrogen ions or reabsorb bicarbonate ions, respiratory acidosis results from respiratory retention of carbon dioxide, and diabetic acidosis results from an accumulation of ketones associated with a lack of insulin. Treatment depends on diagnosis of the underlying abnormality and concurrent correction of the acid-base imbalance. Compare alkalosis. acidotic, adj.

acidosis

A metabolic state characterised by an increase in H+ concentration that occurs when the body can’t buffer free H+ in the blood, which is due either to an accumulation of acid or depletion of the alkaline reserve bicarbonate, resulting in decreased pH in the blood.

ac·i·do·sis

(as-i-dō'sis)
A pathologic state characterized by an increase in the concentration of hydrogen ions in the arterial blood, with pH below the normal range of 7.35 to 7.45; the condition may be caused by an accumulation of carbon dioxide or acidic products of metabolism (respiratory acidosis), or by a decrease in the concentration of alkaline compounds (metabolic acidosis). Various forms include metabolic and respiratory.
[acid + G. -ōsis, condition]

acidosis

A serious condition in which the acidity of the blood rises (pH falls). The blood acidity is normally kept within narrow limits by automatic, feedback mechanisms, and acidosis occurs only in extreme and unusual circumstances such as severe untreated DIABETES (when acid ketone bodies are produced) or advanced kidney disease. Also called acidaemia.

acidosis

a body condition in which there is excessive acidity in body fluids, normally regulated by the kidney.

Acidosis

A disturbance of the balance of acid to base in the body causing an accumulation of acid or loss of alkali (base). There are two types of acidosis: metabolic and respiratory. One of the most common causes of metabolic acidosis is an overdose of aspirin. Respiratory acidosis is caused by impaired breathing caused by conditions such as severe chronic bronchitis, bronchial asthma, or airway obstruction.

acidosis

condition due to decrease in pH of body fluids, from accumulation of acid or depletion of alkali. metabolic acidosis can occur by accumulation of H+ during high-intensity exercise, due mainly to an increased rate of anaerobic glycolysis and therefore of lactic acid production. Pathological causes include diabetic ketoacidosis and severe kidney disease. respiratory acidosis is caused by carbon dioxide retention due to inadequate ventilation, in lung disease, or in respiratory depression by drugs. In compensated acidosis pH may be normal, with a high blood bicarbonate concentration (due to increased renal retention) when the cause was respiratory, or with a low blood carbon dioxide (due to hyperventilation) when the cause was metabolic. See also glycolysis, lactic acid.

acidosis

pathophysical disorder characterized by hydrogen (H+) ion increase or base (OH-) loss, so that the tissue pH can no longer be maintained at 7.4
  • metabolic acidosis acidosis caused by ketone body accumulation; characterized by diarrhoea, vomiting and dehydration and hyperventilation (Kussmaul respiration/air hunger)

acidosis (a·s·dōˑ·sis),

n an imbalance in the acid-base balance in the body, in which blood pH falls below the normal range (7.35–7.45) as the result of a build-up of acid or a depletion of a base, thus resulting in elevated hydrogen ion levels.

acidosis 

An abnormal condition characterized by an increase in acidity and a relative decrease in alkaline content of the blood and body tissues. Corneal acidosis occurs as a result of contact lens wear, especially low gas permeable lenses, due to an accumulation of lactic acid and an increase in the concentration of carbon dioxide (hypercapnia), which is associated with a lower pH. This leads to polymegethism and polymorphism of endothelial cells.

ac·i·do·sis

(as-i-dō'sis)
A pathologic state characterized by an increase in the concentration of hydrogen ions in the arterial blood above the normal level, 40 nmol/L, or pH less than 7.4; may be caused by increased carbon dioxide or by decreased alkaline compounds.
[acid + G. -ōsis, condition]

acidosis (as´idō´sis),

n a pathologic disturbance of the acid-base balance of the body characterized by an excess of acid or inadequate base. Causes include acid ingestion, increased acid production such as that seen in diabetes mellitus or starvation, or loss of base through the kidneys or intestine.
acidosis, compensated,
n a condition of acidosis in which the body pH level is maintained within the normal range through compensatory mechanisms involving the kidneys or lungs.
acidosis, respiratory,
n an acidemia resulting from retention of an excess of CO2 caused by hypoventilation.
acidosis, uncompensated,
n an acidosis in which compensatory mechanisms are unable to maintain the body pH level within the normal range.

acidosis

a pathological condition resulting from accumulation of acid or depletion of the alkaline reserve (bicarbonate content) in the blood and body tissues, and characterized by increase in hydrogen ion concentration (decrease in pH).
The optimal acid-base balance is maintained by chemical buffers, biological activities of the cells, and effective functioning of the lungs and kidneys. The opposite of acidosis is alkalosis.
It is rare that acidosis occurs in the absence of some underlying disease process. The more obvious signs of severe acidosis are muscle twitching, involuntary movement, cardiac arrhythmias, disorientation and coma.

compensated acidosis
a condition in which the compensatory mechanisms have returned the pH toward normal.
diabetic acidosis
a metabolic acidosis produced by accumulation of ketones in uncontrolled diabetes mellitus.
hypercapnic acidosis
respiratory acidosis.
iatrogenic acidosis
may result from administration of drugs, such as urinary acidifiers, or anesthetic agents which depress respiration.
lactic acidosis
the accumulation of lactate in the rumen in ruminants and the stomach of horses, and hence in the blood, as a result of overfeeding with readily fermentable carbohydrate. See also carbohydrate engorgement.
metabolic acidosis
acidosis resulting from accumulation in the blood of keto acids (derived from fat metabolism) at the expense of bicarbonate, thus diminishing the body's ability to neutralize acids. This type of acidosis can occur when there is an acid gain, as in diabetic ketoacidosis, lactic acidosis, poisoning and failure of the renal tubules to reabsorb bicarbonate. It can also result from bicarbonate loss due to diarrhea or a gastrointestinal fistula.
mixed alkalosis and acidosis
characterized by low serum chloride, normal or slightly elevated plasma bicarbonate and a very high anion gap.
organic acidosis
accumulation of organic anions occurs in uremia, diabetic acidosis and lactic acidosis, and ingestion of salicylates, ethylene glycol or methanol.
renal tubular acidosis
renal tubular malfunction leads to faulty resorption of bicarbonate or excretion of acid and the production of alkaline urine; types I (distal tubular acidosis) and II (proximal tubular acidosis) are identified.
respiratory acidosis
acidosis resulting from ventilatory impairment and subsequent retention of carbon dioxide.
ruminal acidosis
acidosis caused by an altered metabolic state, usually lactic acidosis, in the rumen.
starvation acidosis
a metabolic acidosis due to accumulation of ketones following a severe caloric deficit.
uncompensated acidosis
a condition in which the compensatory mechanisms have not been applied sufficiently to return the pH of the blood to normal.
uremic acidosis
see metabolic acidosis (above).
References in periodicals archive ?
The above series of equations will allow the determination of the unknown ionic concentrations of calcium, carbonate and bicarbonate ions present in the solution; In summary the three principal reactions governing the dissolution of calcium carbonate are;
The alkalinity of water samples was calculated as concentration of bicarbonate ions, and its values decreased from 6000 mmol [m.
In hard water containing bicarbonate ion and calcium ion two secondary reactions occur at the cathode:
Increasing the respiratory rate and/or depth of respirations, as well as renal retention of bicarbonate ions occur to counteract an acidotic environment.
Although the conversion of bicarbonate ions to carbonic acid will reduce the buffering capacity with distance, the continual tidal influx replenishes bicarbonate concentrations.
These reactions increase the concentration of bicarbonate ions [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] and decrease the concentration of carbonate ions [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII].
Calcium from these rocks would have washed into oceans and combined with abundant bicarbonate ions to form post-glacial carbonate layers around the globe.
There, carbon dioxide combines with water to form carbonic acid, which leaches out calcium, forming either insoluble calcium carbonate or soluble calcium and bicarbonate ions that dissolve into the groundwater and ultimately end up at the bottom of the ocean.
Louis and his colleagues suggest that in underground regions where warm water mixes with cooler water, the temperature difference generates organic compounds from dissolved carbon dioxide or bicarbonate ions, thus helping to sustain life.
The bicarbonate ions cause the hemoglobin to release oxygen molecules, making them more readily available to tissue, N.
We found that this unpleasant scum forms when the tea is brewed in hard water, which has both calcium ions and bicarbonate ions in it," Spiro says.
The scientists think the cloud was mostly carbon dioxide because they found high concentrations of the gas above agitated lake water, as well as high levels of bicarbonate ions in Lake Nyos's bottom waters.