Acidosis

Alternative names: Metabolic acidosis, Respiratory acidosis, Acidemia

Acidosis is defined as a state of increased acidity in the blood and body tissues.  Under normal circumstances the kidneys and lungs automatically compensate for pH imbalances; acidosis occurs when, for some reason, this no longer happens.

Acidosis is defined as an arterial pH below 7.35.  It can lead to numerous health issues, and even death.

There are two types of acidosis, Metabolic Acidosis (caused by overproduction of acid in the blood, or excessive loss of bicarbonate from the blood) and Respiratory Acidosis (a buildup of carbon dioxide in the blood due to impaired lung function or reduced breathing ability).

Causes and Development; Contributing Risk Factors

The naturopathic theory behind a proper dietary acid/alkaline balance is that because our body's blood pH is slightly alkaline, with a normal range of 7.36-7.44, our diet should reflect this preference and tend more towards alkaline foods.  An imbalanced, acidic diet high in animal protein, sugar, caffeine and processed foods tends to disrupt this pH balance.  This deprives the body of alkaline minerals such as sodium, potassium, magnesium and calcium and leaves us prone to chronic and degenerative diseases.

The lungs and kidneys help regulate pH balance

Metabolic acidosis is associated with the kidneys and can be caused by increased production of metabolic acids, reduced ability of the kidneys to excrete acids, or by the kidneys removing too much base.  Many of the body's metabolic processes produce acid.

One type of metabolic acidosis is lactic acidosis, which occurs when there is too much lactic acid in the body.  This can be caused by long-term alcohol abuse, heart failure, cancer, seizures, liver failure, a prolonged lack of oxygen, starvation, or low blood sugar.  Diabetes can also increased acid production: an insulin deficit will lead to increased levels of ketones, which acidifies the blood.  Prolonged exercise can lead to lactic acid buildup, but levels usually return to normal afterwards.

Other possible causes of metabolic acidosis include poisoning, hemochromatosis (iron overload), or decreased production of bicarbonate by the body (hyperchloremic acidosis).  Diarrhea and vomiting can cause excess loss of bicarbonate.

Respiratory acidosis is associated with the lungs and is usually caused by a build-up of carbon dioxide (CO₂) in the blood due to the lungs being unable to remove enough of it.  This can be due to a variety of causes including:

• asthma
• pneumothorax
• (late stage) emphysema
• chronic bronchitis
• severe pneumonia
• chest trauma
• obesity-related breathing difficulty
• sedative misuse (don't mix with alcohol)
• excess alcohol consumption
• muscular dystrophy / chest muscle weakness
• deformed chest
• nervous system dysfunction
• brain tumor
• head injury
• anesthetics
• a mechanism through which the body deals with chronic metabolic alkalosis

Risk factors that increase your chance of developing acidosis include:

• a high-fat diet, low in carbohydrates
• kidney failure
• being obese (this can make it harder to breathe)
• dehydration (drink plenty of water)
• aspirin or methanol poisoning
• having diabetes (make sure it is controlled, to avoid ketoacidosis)
• smoking (damages the lungs and makes breathing less efficient)
• chronic alcohol abuse (drinking increases the buildup of lactic acid)

Signs and Symptoms

Unfortunately most signs and symptoms of acidosis are shared with numerous other conditions, so careful differential diagnosis is required.  They may include:

• headaches
• confusion
• fatigue / tiredness
• shortness of breath
• rapid or slow and/or shallow breathing: as blood becomes more acidic, the brain compensates through faster and deeper breathing to increase the amount of carbon dioxide exhaled
• loss of appetite
• nausea
• vomiting
• jaundice
• tremors
• increased heart rate
• drowsiness / sleepiness
• breath that smells of fruit (a sign of diabetic acidosis or ketoacidosis)
• asterixis ("flapping tremor")
• delirium
• confusion
• reduction of the brain's sensory and neural functions, and its ability to initiate and coordinate voluntary muscle activity

Diagnosis and Tests

Diagnosis involves a series of blood tests which measure:

• the levels of oxygen and carbon dioxide in the blood
• blood pH
• kidney function and pH balance (metabolic panel)
• calcium
• protein
• blood sugar
• electrolyte levels

If metabolic acidosis is suspected, a urine test will check the pH to see if acids and bases are being properly eliminated.

Treatment and Prevention

Treatment for acidosis generally depends on the cause, but some treatments can be used for any type of acidosis, for example sodium bicarbonate (baking soda) to raise the pH of the blood.

Treatment for metabolic acidosis depends on the type.

• Patients with hyperchloremic acidosis can benefit from oral sodium bicarbonate
• Those with acidosis from kidney failure can be treated with sodium citrate
• Diabetics with ketoacidosis receive IV fluids and insulin to balance their pH
• Lactic acidosis patients might receive bicarbonate supplements, IV fluids, oxygen, or antibiotics, depending on the cause.

Treatment for respiratory acidosis often involves drugs to dilate the airway and/or a CPAP device to help with breathing.

Prevention involves reducing the risk factors.

Prognosis; Complications

Some patients will fully recover from acidosis; others will suffer complications.

Possible complications resulting from acidosis include:

• kidney stones
• chronic kidney problems
• kidney failure
• heart problems
• respiratory failure
• bone disease
• delayed or stunted growth

Left untreated, severe acidosis can cause shock, coma or even death.