Treatment of acute posthemorrhagic anemia in children

Treatment of a patient with acute blood loss depends on the clinical picture and volume of blood loss. All children with clinical or anamnestic data suggesting blood loss of more than 10% of the BCC are subject to hospitalization.

The circulating blood volume and hemodynamic parameters should be assessed immediately. It is extremely important to repeatedly and accurately determine the main parameters of central hemodynamics (heart rate, blood pressure and their orthostatic changes). A sudden increase in heart rate may be the only sign of recurrent bleeding (especially in acute gastrointestinal bleeding). Orthostatic hypotension (a decrease in systolic blood pressure > 10 mm Hg and an increase in heart rate > 20 bpm when moving to a vertical position) indicate moderate blood loss (10-20% of the CBV). Arterial hypotension in the supine position indicates significant blood loss (> 20% of the CBV).

It is generally accepted that in acute blood loss, hypoxia occurs in a child after the loss of > 20% of the BCC. Children, due to a lower affinity of hemoglobin for oxygen than in adults, are able in some cases to compensate for blood loss even at a Hb level of < 70 g/l. The issue of transfusion in each child must be decided individually, taking into account, in addition to the amount of blood loss, hemodynamic parameters and red blood, such factors as the ability to compensate for reduced oxygen function, the presence of concomitant diseases, etc.

Treatment of the patient begins with both immediate stopping of bleeding and bringing the child out of shock. In the fight against shock, the main role is played by restoration of the circulating blood volume with blood substitutes and blood components. The volume of blood loss should be replaced with red blood cells or (if unavailable) with whole blood of short shelf life (up to 5-7 days). Transfusions of crystalloid (Ringer's solution, 0.9% NaCl solution, lactasol) and/or colloid (rheopolyglucin, 8% gelatinol solution, 5% albumin solution) blood substitutes should precede hemotransfusions, which allows restoring the circulating blood volume, stopping microcirculation disorders and hypovolemia. It is advisable to initially administer a 20% glucose solution (5 ml/kg) with insulin, vitamin B ₁₂ and cocarboxylase (10-20 mg/kg). The rate of administration of blood substitutes under conditions of stopped bleeding should be at least 10 ml/kg/h. The volume of transfused blood substitute solutions should exceed (approximately 2-3 times) the volume of red blood cell mass.

When restoring the BCC with blood substitutes, it is necessary to ensure that the hematocrit is not lower than 0.25 l/l due to the risk of developing hemic hypoxia. Transfusion of red blood cell mass compensates for the deficiency of red blood cells and stops acute hypoxia. The dose of blood transfusion is selected individually depending on the amount of blood loss: 10-15-20 ml/kg of weight, and more if necessary. Restoration of hemodynamics, including central venous pressure (up to 6-7 mm H2O), is an indicator of the sufficiency and effectiveness of infusion-transfusion therapy for acute blood loss.

Indications for red blood cell transfusion in acute blood loss are:

1. acute blood loss > 15-20% of the BCC with signs of hypovolemia, not relieved by transfusions of blood substitutes;
2. surgical blood loss > 15-20% of the BCC (in combination with blood substitutes);
3. postoperative Ht < 0.25 l/l with clinical manifestations of anemia (Ht < 0.35 l/l, Hb < 120 g/l) in severe restrictive diseases (artificial ventilation);
4. Ht < 0.25 l / l Hb < 80 g / l with clinical manifestations of anemia, active bleeding;
5. iatrogenic anemia (< 5% of BCC) due to blood sampling for laboratory tests (Ht < 0.40-0.30 l / l).

Indications for blood transfusions: acute massive blood loss, open heart surgery. It is important to remember that blood transfusions carry a high risk of transmitting viral infections (hepatitis, cytomegalovirus, HIV), sensitization.

Newborns with acute posthemorrhagic anemia and hemorrhagic shock require intensive care. A newborn in shock should be placed in an incubator or under a radiant warmer to maintain body temperature at 36.5 °C and provided with inhalations of oxygen-air mixtures.

Indications for blood transfusions in newborns are:

1. anemia with contractile heart failure (1 ml/kg body weight, slowly over 2-4 hours); repeat transfusions if necessary;
2. Hb < 100 g/l with symptoms of anemia;
3. Hb < 130 g/l in children with severe respiratory diseases;
4. Hb < 130 g/l at birth;
5. loss of BCC 5-10%.

For transfusion, red blood cell mass (not older than 3 days) is used, which is administered slowly (3-4 drops per minute) in the amount of 10-15 ml/kg of body weight. This leads to an increase in the hemoglobin level to 20-40 g/l. In severe anemia, the required amount of red blood cell mass for transfusion is calculated using the Naiburt-Stockman formula:

V = m (kg) x Hb deficit (g/l) x CBF (ml/kg) / 200, where V is the required amount of red blood cell mass, 200 is the normal hemoglobin level in the red blood cell mass in g/l.

For example, a child weighing 3 kg is diagnosed with anemia with a hemoglobin level of 150 g/l, which means hemoglobin deficiency = 150 - 100 = 50 g/l. The required amount of red blood cell mass will be 3.0 x 85 x 50/200 = 64 ml. With very low hemoglobin levels in a child, the desired Hb level, by which hemoglobin deficiency is determined, is considered to be 130 g/l.

Indications for red blood cell transfusion in children older than the first days of life are hemoglobin levels below 100 g/l, and in children older than 10 days - 81-90 g/l.

To avoid complications of massive blood transfusion (acute heart failure, citrate intoxication, potassium intoxication, homologous blood syndrome), the total volume of blood transfusion should not exceed 60% of the BCC. The remaining volume is replenished with plasma substitutes: colloidal (rheopolyglucin, 5% albumin solution) or crystalloid (Ringer's solution, 0.9% NaCl solution). If it is impossible to urgently perform a blood transfusion for a child in posthemorrhagic shock, then treatment with plasma substitutes is started, since the discrepancy between the circulating blood volume and the capacity of the vascular bed must be eliminated immediately. The limit of hemodilution in the first hours of life is considered to be a hematocrit of 0.35 l/l and a red blood cell count of 3.5 x 10 ¹² /l. When this limit is reached, BCC replenishment must be continued with blood transfusions.

The effectiveness of therapy for acute posthemorrhagic anemia is judged by the normalization of the color and temperature of the skin and mucous membranes, an increase in systolic blood pressure to 60 mm Hg, and restoration of diuresis. Laboratory monitoring: Hb level 120-140 g/l, hematocrit 0.45-0.5 l/l, CVP within 4-8 cm H2O (0.392-0.784 kPa), BCC above 70-75 ml/kg.

A patient with acute posthemorrhagic anemia requires bed rest. The child is warmed and given plenty of fluids.

According to indications, cardiovascular drugs and medications that improve microcirculation are prescribed.

At the end of the acute period, a full diet is prescribed, enriched with proteins, microelements, vitamins. Taking into account the depletion of iron reserves, treatment with iron preparations is prescribed.