Acute expansion of the heart is an overstretching of the cardiac muscle, resulting from a sharp increase in CBV with incorrect calculation of the dose and the rate of infusion / transfusion. It is manifested by a rapid increase in systolic blood pressure, signs of respiratory failure, chest pain. The development of pulmonary edema is possible. A history of coronary heart disease, congenital cardiac defects, anemia is usually present. The diagnosis is established on the basis of the clinical picture, the fact of violation of the transfusion technique, laboratory and hardware examination data. Treatment includes diuretics, inhalation of O2 passed through a defoamer, cardiac remedies, plasmapheresis.
ICD 10
T80.8 Other complications associated with infusion, transfusion and therapeutic injection
General information
Acute expansion of the heart is the main symptom of volemic overload, which causes all further manifestations of this pathology. Occurs with the rapid introduction of a large volume of infusion solutions or blood products. The condition often develops in patients suffering from diseases of the cardiological profile, chronic anemia, pulmonary diseases. In pediatrics, hypervolemic syndrome is detected in newborns who need to replenish the CBV. Even a small volume of intravenously administered fluid leads to the development of dilation in patients from these groups. It is believed that the risk of acute expansion of the heart in predisposed patients increases many times if the infusion rate is more than 1 ml / h per kilogram of body weight.
Causes
Fluid overload in patients without chronic diseases practically does not occur, since the heart copes with increased BCC, and excretion systems quickly remove excess water from the body. Acute expansion of the heart in a healthy person develops only with a very large excess of the permissible volume of infusion, which in practice is extremely rare. Hypervolemic syndrome, including coronary dilation, is usually diagnosed in the presence of the following predisposing factors:
- Kidney failure. A decrease in the functionality of the urinary system leads to a slow removal of excess water and metabolic products from the body. A positive fluid balance is created, in which the volume of incoming H2O significantly exceeds the amount of urine. The severity of the condition directly depends on the severity of the water imbalance.
- Heart failure. In the presence of CHF, the heart works at the limit of its residual resources. It is unable to fully pump even the volume of blood that is constantly present in the body. A sharp filling of the vessels with additional fluid provokes an excessive increase in preload, there is an acute expansion of the cardiac chambers, there is an even greater decrease in their functionality.
- Respiratory pathology. With bronchectasia, vasculitis, bronchial asthma, COPD, the pressure in the small circle of blood circulation increases. This increases the load on the right departments and contributes to their expansion, potentiates the mechanical disruption of the left ventricle. An acute or chronic pulmonary heart is formed. The further process of formation of changes does not differ from that of CHF.
Pathogenesis
The mechanism of pathology development is relatively simple. A sharp increase in the volume of fluid circulating in the vessels increases the load on the venous-arterial apparatus and the heart. The latter is unable to pump the necessary amount of blood. Hemoral surpluses accumulate in it, the walls stretch, the organ loses the ability to fully contract. Stagnation occurs in both circulatory circles. On the periphery and in the lungs, there is an increased proliferation of plasma into soft tissues, massive edema forms.
Ascites may form, which causes an increase in intraabdominal pressure, followed by a violation of the function of internal organs. There is a compression of the diaphragm, which further aggravates respiratory failure. Perspiration of the transudate into the interstitial space or alveoli provokes pulmonal edema, which is accompanied by a sharp deterioration in ventilation with the development of an appropriate clinical picture. The patient’s death occurs from severe respiratory and cardiovascular insufficiency, asystole.
Symptoms
At the initial stage, the pathology is manifested by a rapid increase in systolic blood pressure. Diastolic blood pressure indicators do not rise so significantly. The difference between the “upper” and “lower” results of tonometry increases. The patient’s pulse is characterized by weak filling and tension, tachycardia is detected. The patient experiences severe headache, difficulty breathing is detected. Bronchospasm may occur with the formation of an attack of cardiac asthma.
As the process develops, the symptoms increase. There are signs of peripheral circulatory insufficiency (blue tint of the lips, nasolabial triangle, earlobes, fingertips) and hypoxia (diffuse cyanosis, inclusion of auxiliary muscles in the breathing process, inflating of the wings of the nose, psychomotor agitation). Blood pressure decreases due to a decrease in the strength of heart contractions. Tachycardia persists and is compensatory in nature.
At the terminal stage of acute expansion of the heart, all its manifestations reach a maximum. White or pinkish foam is released from the mouth, pronounced cyanosis of the skin is noted, heart rate and blood pressure drop to critical values. Psychomotor agitation is replaced by depression of consciousness. The heart rhythm is disturbed, ventricular fibrillation occurs, accompanied by respiratory and circulatory arrest. There comes a stage of clinical death, which, in the absence of medical care, turns into biological in 3-5 minutes.
Complications
According to research, the probability of death of the patient increases by 20% with each liter of positive total water balance. The overall survival rate of patients with excess fluid within 1-4 liters does not exceed 25%. The cause of death is alveolar edema, cerebral edema, acute decrease in the contractility of the heart. With successful timely relief of hyperhydration, reactivation of chronic coronary diseases may occur, the development of CHF due to overstretching of the cardiac chambers. After an episode of severe hypoxia on the background of edema, brain damage may occur up to decortication (cerebral death) or posthypoxic encephalopathy.
Diagnostics
Taking into account the fact that massive infusion or transfusion is carried out exclusively in the ICU or operating room, the diagnosis of dilation is carried out by an anesthesiologist-resuscitator. It is imperative to differentiate acute heart enlargement with pulmonary edema and increased heart failure of another etiology. This may require consultations with a cardiologist, a cardiac surgeon, a specialist in functional diagnostics. To clarify the nature of the existing violations , the following laboratory and hardware techniques are used:
- Physical examination. It includes examination of the patient, palpation, percussion and auscultation of the lungs, heart. There is a displacement of the coronary boundaries, a change in cardiac tones and rhythm. Hard breathing is heard, large-bubbly wheezing, crepitation may be present. When tapping, the dulling of the percussion sound is determined.
- Laboratory examination. Hypoxemia is present (PaO2 ≤ 95 mmHg), respiratory alkalosis (pH ≥ 7.35, PaCO2 ≤ 40 mmHg). In the presence of concomitant changes on the part of the cardiovascular system (AMI due to overstretching of the coronary wall and a decrease in the capacity of the arteries), an increase in the level of troponin, myoglobin, CK, CK-MV may be noted.
- Hardware inspection. During the ultrasound of the heart, the expansion of its chambers and boundaries is detected. On the ECG there are signs of arrhythmia of one type or another, the displacement of the electrical axis up to the horizontal position. The X-rays visualize the strengthening of the vascular pattern, the expansion of the coronary shadow, the appearance of Curling lines. The central venous pressure rises to 14 mm of water column or more.
Intensive care
Therapy of volemic overload is aimed at normalizing vital signs. Treatment is considered effective, as a result of which the heart rate decreases to 90-100, the CVP – to 8-12 mm, the lactate level – 1-2 mmol / liter. The heart rhythm should be restored, the phenomena of pulmonal edema are stopped. During auscultation, the cured patient has no wheezing, other signs of accumulation of transudate. As restorative measures, general measures, medical and resuscitation benefits are used:
- General events. At the first signs of an acute type of expansion, it is necessary to stop the supply of infusion solution into the venous bed. The patient should be given a sitting or semi-sitting position, this allows you to deposit some of the blood in the legs and reduce preload. Short-term application of venous tourniquets on three of the four limbs is allowed.
- Medicines. Loop diuretics are shown. This makes it possible to quickly remove excess water naturally, without resorting to plasmapheresis. Inhalation of oxygen passed through 70% ethyl alcohol is used. With a significant weakening of cardiac activity, an infusion of inotropic drugs is necessary: dopamine, dobutamine, levosimendan, glycosides. Pulmonary edema requires the administration of morphine or promedol.
- Intensive care. With severe ODN, the patient is intubated, transferred to artificial respiratory support. Perform round-the-clock monitoring of the condition with the help of an anesthesiological monitor. They provide central venous access, indispensable for measuring CVD and rapid administration of drugs into the vascular bed. If necessary, excessive volumes of fluid can be removed using the plasmapheresis procedure.
Prognosis and prevention
The prognosis is unfavorable. Mortality in the absence of timely assistance reaches 75%. If coronary dilation was detected at the initial stage, the chances of a successful outcome increase, the mortality rate does not exceed 18-20% of the total number of cases. Prevention consists in the correct calculation of the required volume of infusion or transfusion by the doctor conducting the treatment. It should be borne in mind that the infusion rate in patients with existing predisposing factors should be minimal. Even more careful tactics of a specialist requires the appointment of solutions to infants.