Lactic acidosis in type 2 diabetes mellitus, its symptoms and treatment

Development mechanism

With normal metabolism, lactate (a derivative of lactic acid) and pyruvate (a derivative of pyruvic acid) are necessarily present in the blood. They have a ratio of 1:10. With impaired metabolism, the lactate content increases threefold or more, and causes metabolic acidosis, aggravated by hypoxia. The blood environment shifts to the acidic side, which increases insulin resistance, which, in turn, increases the synthesis of lactic acid. A “vicious circle” is formed.

This condition provokes an accelerated breakdown of pyruvic acid due to a lack of insulin. This fact contributes to the formation of an excess of lactic acid, which is very harmful to health.

Further, with increased insulin resistance, counter-insular hormones responsible for carbohydrate metabolism begin to be actively produced, which distorts fat metabolism and increases the level of free fatty acids. The process negatively affects the central nervous system and causes pathoneurological symptoms.

Intoxication, acidosis and loss of moisture lead to diabetic coma. Intoxication is aggravated by abnormal protein metabolism, which contributes to the appearance of hyperazotemia (increased percentage of metabolic products in the blood).

As a result, we observe:

Where does lactic acidosis come from?

Lactate is a natural by-product of lactic acid from the breakdown of glucose and amino acids. In a healthy body, it is produced in minimal doses and breaks down into water, carbon dioxide or glucose. Decomposition products are excreted through the kidneys. When their accumulation occurs (lactic acidosis), the acidity of arterial blood increases sharply, the enrichment of cells with oxygen decreases, and the effect of insulin decreases. As a result, hyperglycemic coma occurs.

Based on the nature of the clinical picture and the degree of progression, early, middle and late stages are distinguished. The patient's condition changes in just a few hours, the symptoms change sharply from general malaise to coma. The classification based on etiopathogenetic mechanisms, developed in 1976 by Cohen and Woods, distinguishes several types of lactic acidosis:

Acquired - type A, manifests itself after 35 years, can develop even in the absence of diabetes. Tissue hypoxia (oxygen starvation of cells) inhibits the functions of the central nervous system and accelerates the respiratory and pulse rates.
Congenital - type B, occurs due to the underlying disease (diabetes mellitus), toxin breakdown products, and congenital problems with metabolism. Causes kidney or liver failure.

In the international statistical classification (ICD-10), lactic acidosis refers to disorders of water-salt and acid-base balance.

Causes

Lactic acidosis in type 2 diabetes occurs, as a rule, due to a combination of several factors, which include:

increased production of lactic acid due to taking biguanides (tablets that lower blood sugar levels), severe decompensation of diabetes, diabetic ketoacidosis; acidosis of another origin;
decreased clearance of lactic acid in alcoholism, liver pathologies;
a one-time decrease in the clearance of lactic acid and biguanides in case of impaired renal function or intravenous administration of radiocontrast agents;
tissue hypoxia as a result of heart failure, coronary heart disease, pathologies in peripheral arteries, diseases of the respiratory system, anemia of various types;
a combination of reasons that provoke the accumulation of lactic acid (deterioration of the general condition of the body, malignant neoplasms, acute stress, complications of diabetes, age over 60 years, severe injuries, concomitant diseases of an infectious or inflammatory nature, bleeding, AIDS, etc.);
lack of thiamine (vitamin B1) in the body.

Pregnancy is also a cause of lactic acidosis in type 2 diabetes mellitus

The occurrence of this complication cannot be predicted; all causes are relative. If the patient is at risk, it is necessary to take both the drug metformin and other drugs containing it.

Symptoms

Symptoms of lactic acidosis appear suddenly, develop over several hours and without timely medical attention lead to irreversible consequences. In this case, no precursors are observed.

The only initial symptom unique to lactic acidosis is muscle pain (myalgia), in the absence of intense physical activity. The remaining symptoms that develop at the initial stage of lactic acidosis may be characteristic of various health disorders.

The complication is characterized by:

pain syndromes in the abdominal area;
diarrhea, vomiting, heartburn;
delayed urine flow or complete cessation;
drowsiness or, conversely, insomnia;
weakness;
shortness of breath;
apathy;
feeling of heaviness behind the sternum.

Dry skin may indicate lactic acidosis

Lactate levels increase rapidly, which further leads to:

compensatory hyperventilation due to tissue hypoxia. This results in noisy breathing that can be heard at a distance of several meters, in some cases turning into groans (Kussmaul breathing). When exhaling, there is no smell of acetone;
acute cardiovascular failure, which cannot be eliminated by standard methods. There is a sharp drop in blood pressure. The situation is aggravated by impaired heart rhythm, which can lead to myocardial infarction and collapse;
involuntary muscle contraction leads to cramps;
lack of oxygen and glucose in the brain leads to neurological reactions. Increased excitability (hyperkinesis) or paresis occurs. Concentration is impaired. The state of delirium is replaced by stupor;
intravascular coagulation (DIC syndrome). This symptom is very dangerous. Even after the symptoms of lactic acidosis have stopped, blood clots continue to move through the circulatory system, which can lead to thrombosis (blockage of blood vessels). This is fraught with the occurrence of necrosis of the fingers and the penis in men. This pathology provokes gangrene, and subsequently amputation.

Next comes a comatose state.

The clinical picture of lactic acidosis is similar to the symptoms of pathological effects on the body of methanol, acetic acid, salicylates, as well as ketoacidosis.

It must be remembered that first aid when symptoms of lactic acidosis occur is to urgently hospitalize the patient. When muscle pain occurs, the sugar level is measured, and if there is a sharp deterioration in health, an ambulance is called. Self-treatment of the complication will lead to adverse consequences.

Symptoms of lactic acidosis

The first signs of pathology are dyspeptic disorders, muscle pain, attacks of sudden pain in the chest, complete ineffectiveness of painkillers. The patient develops disturbances of consciousness. This condition sometimes resembles alcohol intoxication.

With lactic acidosis, abdominal pain often occurs, vomiting, diarrhea, tachypnea and hypothermia are also characteristic. Cardiovascular arrhythmias, hypotension and decreased cardiac output are possible. The neurological picture can be equally varied: from mild confusion, asthenia to deep coma.

If the patient's condition worsens sharply, it is necessary to act immediately:

Call an ambulance;
If the patient is breathing and the pulse is palpable, it is necessary to provide him with access to fresh air and place him on his left side;
If a person is unconscious, the pulse cannot be felt, there is no breathing - proceed to chest compressions;
If a person is unconscious, do not try to give him something to drink.

Diagnostics

Diagnosis of lactic acidosis is carried out exclusively in a medical institution and includes:

Collecting anamnesis by interviewing the patient or accompanying persons.
Study of symptoms of a pathological condition.
A blood test that measures lactic acid levels, anion gap, and acid-base status.

With lactic acidosis, the level of lactic acid in the blood should be 2.2–5.0 mmol/l, and the pH in the blood should not be higher than 7.25. The diagnosis is confirmed by a low bicarbonate level of less than 18 mEq/L and an increased anion gap (the difference in concentration between sodium and the sum of chloride and bicarbonates) of more than 16 mEq/L.

Diabetic lactic acidosis is also differentiated from:

ketoacidosis, in which the mouth smells of acetone and the appearance of hyperketonemia and ketonuria is observed;
uremic acidosis, which is characterized by an increased level of creatinine in the blood (over 180 µmol/l).

Diagnosis of lactic acidosis should be carried out at a professional level

Treatment

In a hospital setting, it is necessary to eliminate hypoxia and acidosis as soon as possible.

Normalization of pH in the blood occurs through intravenous administration of sodium bicarbonate. At the same time, the potassium content in the blood is monitored, as well as pH values. This drug can cause negative side effects, including swelling of the brain. For this reason, this method is used when the pH drops below 7.0; the dosage of the product should not be more than 2 liters per day.

To bring the patient out of a coma, the drug trisamine and methylene blue are used.

Elimination of hypoxia can be carried out using oxygen therapy, as well as artificial ventilation.

In addition to the necessary insulin therapy, intensive and monocomponent insulin therapy is carried out.

If the patient consumed biguanides immediately before the onset of complications, his stomach is washed and enterosorbents (activated carbon, etc.) are prescribed. In some cases, hemodialysis is used to accelerate the removal of lactic acid.

For anti-shock measures, plasma replacement solutions and adrenergic agonists (Dopamine, Norepinephrine, etc.) are used.

Small doses of heparin eliminate DIC syndrome.

Additional factors that contributed to lactic acidosis (severe infections, anemia, etc.) are also eliminated.

Regular communication with your doctor reduces the risk of diabetes complications

Preventive measures

The second type of diabetes is a disease that requires constant monitoring of your health:

undergo regular examinations with a doctor;
do not self-medicate. All medications should be taken only in consultation with a doctor. Otherwise, if they overdose, excess production of lactic acid may occur;
take the necessary measures to avoid viral diseases;
monitor for changes in health status when using biguanides;
follow a diet, physical activity and daily routine;
If alarming symptoms appear, immediately call an ambulance.

Very often, the patient learns about the presence of diabetes mellitus only after diagnosing lactic acidosis. Annual blood sugar tests will help you avoid this dangerous disease.

Metabolic acidosis

The acid-base balance in the blood is a vital parameter. Its normal values range from 7.35 to 7.45 on the pH scale. If the pH drops below 7.35, the patient has acidosis. If it rises above 7.45, this means that the patient has alkalosis.

Alkalosis and acidosis are metabolic (metabolic) and respiratory (respiratory). It depends on the reasons for their development.

Respiratory acidosis develops when a lot of carbon dioxide accumulates in the blood, forming carbon dioxide when combined with water. Because of this, the acidity of the blood increases. This condition can develop with respiratory disorders that cause decreased pulmonary ventilation.

The disease can also develop due to lung disease (for example, bronchial asthma), damage to the nervous system (for example, brain injury), nerve and muscle diseases that lead to loss of the ability to make effective respiratory movements (amyotrophic lateral disease is one such disease). sclerosis).

The opposite condition is called respiratory alkalosis and occurs when the lungs begin to remove carbon dioxide from the body in excess. This occurs due to an increase in the rhythm of breathing and its depth.

Such a respiratory disorder can occur in the presence of pathology on the part of various systems and organs (for example, with lung diseases, tumors and brain injuries, cardiovascular failure).

Metabolic acidosis can develop for the following reasons:

increasing the production of acids by the body. This can be observed in conditions that are accompanied by metabolic disorders: diabetes mellitus, when cells begin to suffer from impaired glucose use due to a lack of the hormone insulin. (The body produces energy not from glucose, but from fats - this path is an alternative. When fats are broken down in the liver, many ketone acids are formed, which provoke the appearance of acidosis).
impaired renal function. The kidneys play an important role in the process of regulating the acid-base balance in the blood. If a patient has kidney diseases that can lead to disruption of their functions, the processes of absorption of substances with an alkaline reaction and the processes of acid secretion may also be disrupted. This may cause acidosis.
loss of a large amount of alkalis along with digestive juices. This condition can be observed in the case of various operations on the intestines, with severe diarrhea.
poisoning by toxic substances, poisons. These substances can be broken down in the body, producing excessive amounts of acids. This can cause acidosis.

The main causes of metabolic alkalosis are the following:

use of diuretics (diuretics);
loss of acidic gastric contents in large quantities: this occurs when aspiration of stomach contents through a special probe, with profuse vomiting;
excessive excretion of hydrogen ions by the kidneys. This can occur when the body has an excess of aldosterone, an adrenal hormone that takes part in the regulation of water and electrolyte balance. Its level can increase both in diseases of the adrenal glands and in pathologies of other organs (for example, in heart failure).

That is, the development of alkalosis or acidosis is most often caused by the occurrence of pathological processes in the patient’s body, during which the acid-base balance changes, and the compensatory capabilities of the body are insufficient.

Symptoms

Very often, the symptoms of alkalosis and acidosis are masked by signs of the underlying disease, which provoked a change in the acid-base balance in the patient’s blood.

Symptoms of acidosis may include the following:

rapid breathing;
various disturbances of consciousness (up to coma);
heart rhythm disturbances;
headache;
vomiting and nausea;
decreased blood pressure (observed in severe forms).

With alkalosis, the following symptoms are observed:

dizziness;
heart rhythm disturbances;
cramps in different muscle groups;
headache;
disturbances of consciousness (up to coma).