Respiratory disorders – Kussmaul breathing

Anyone who observes Kussmaul breathing in someone, especially the layman, knows intuitively that something serious is going on. This very deep breathing usually indicates renal insufficiency or a hyperglycemic coma, or diabetic coma. Rapid medical intervention is then necessary. Kussmaul breathing is characterized by slowed or rapid, deep breathing to counteract the threat of acidification (acidosis). It’s a kind of hyperventilation. This type of breathing can also be accompanied by snoring.


  • Acidification (acidosis) and alveoli
  • The deep, slow Kussmaul breathing
  • Symptoms
  • Causes of Kussmaul breathing
  • Coma diabeticum (hyperglycemic coma)
  • Symptoms
  • Complication
  • Renal insufficiency (kidney failure)
  • Causes

Acidification (acidosis) and alveoli

Kussmaul breathing involves metabolic acidification (acidosis), i.e. as a result of metabolic problems. This means that the body wants to get rid of as much carbon dioxide as possible through the lungs. This happens via the alveoli , of which each lung contains approximately 150 million. The wall of the alveoli is lined with epithelial cells and surrounded by numerous capillaries. The distance between the blood and the air (in the lungs) is therefore very small. In addition, this construction increases the total surface area (approx. 80 m²) of the lungs . Gas exchange takes place in the alveoli.

Carbon dioxide (carbon dioxide) diffuses from the lungs twenty times faster than oxygen is absorbed into the blood through the alveoli. In lung diseases, such as pulmonary edema and emphysema, the oxygen supply is the first to be compromised. Kussmaul breathing is the result of progressive metabolic acidification, in contrast to respiratory acidification where the cause lies in the lungs themselves (as in COPD) or due to intoxication (sleeping pills, painkillers and opiates, such as oxycodone).

Kussmaul breathing / Source: Frivadossi, Wikimedia Commons (CC BY-SA-3.0)

The deep, slow Kussmaul breathing

The phenomenon is named after Adolph Kussmaul (1822-1902), a renowned German physician who published about it in 1874 after a thorough study of this breathing type. It concerns deep, slow and difficult, almost panting (air hunger) breathing. However, in the early stages of acidosis, the breathing pattern is rapid and shallow.


As acidosis increases, breathing will also become more labored, the rate of which may be normal or slowed. The symptoms of Kussmaul breath type are:

  • Deep, slowed and generally regular breathing (rapid and shallow at first).
  • In the final stage, abnormally slow, deep breathing, i.e. fatal progressive comatose acidosis.
  • This type of breathing is often accompanied by snoring. Kussmaul called this pathological form of breathing the harbinger of deep diabetic coma and impending death in diabetes patients.

Causes of Kussmaul breathing

This type of breathing is always the result of acidosis, for example due to kidney failure (uremia), where the electrolyte balance is disturbed and there is an abnormal increase of acidic waste products in the blood. There are many causes of acidosis. With regard to Kussmaul breathing, a number of conditions strongly contribute to its development, such as diabetic coma and renal failure (renal insufficiency).

Coma diabeticum (hyperglycemic coma)

Kussmaul breathing occurs in completely disordered diabetes. Not only is the sugar metabolism disrupted, the fat metabolism is also affected. In addition to the high blood sugar level, breakdown products of fats are also detectable, such as acetone, diacetic acid and beta-oxybutyric acid. These substances poison the body and cause the infamous diabetic coma. In diabetics, this disrupted sugar metabolism sometimes occurs during an infectious disease, i.e. when there is a great need for insulin, which the body cannot meet and which is also administered too late.


Due to the comatose state, the reflexes are absent and breathing is slowed and very deep, or Kussmaul breathing. The symptoms of diabetic coma include:

  • Deep Kussmaul breathing (due to acidification of the body).
  • No reflexes.
  • High glucose level in the blood.
  • Acetone, diacetic acid and glucose in the urine.
  • Breath smelling like acetone.
  • General muscle relaxation (shock).
  • Dehydration.


Diabetic coma is a serious complication of diabetes, which also affects the kidneys (renal insufficiency). If no action is taken, the patient will die. However, thanks to improved treatment methods, hyperglycemic coma is still rare.

Adolph Kussmaul (1822-1902) / Source: Reclams Universum 1902, Wikimedia Commons (Public domain)

Renal insufficiency (kidney failure)

In kidney failure, the word says it all, even if the kidneys no longer work or hardly work anymore. As a result, urine production has also stopped and the blood is no longer purified of waste products. As with hyperglycaemic coma, acidification occurs, causing, among other things, the urea and creatinine levels in the blood to rise.


Renal insufficiency can also be the result of diabetic coma. The sudden loss of kidney function, or acute renal failure , can have many causes, such as:

  • Dehydration.
  • Shock.
  • Sepsis (blood poisoning).
  • Pancreatitis (inflammation of the pancreas).

Kidney cysts
In chronic renal insufficiency , loss of function occurs gradually. This may be the result of, for example, kidney cysts.

read more

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