Normal heart rate readings in a child

Heart rate characteristics in childhood

Pulse - oscillation of the walls of blood vessels (arteries), spreading from the aorta in response to changes in the amount of blood and pressure inside it during the cardiac cycle. These shocks are synchronous with the systole of the ventricles and are normally equal to the heart rate. The main method for determining the frequency and rhythm of the pulse is palpation examination of the large arteries (radial, carotid, femoral, popliteal).

Pulse indicators directly depend on the work of the heart, which in childhood differs from an adult in anatomical and physiological features.

The organ of the newborn has a large mass relative to the body. Moreover, the size of the ventricles is smaller than the atria. As a result, with each contraction, a small amount of blood is thrown into the aorta. Therefore, to provide the necessary blood flow, the heart is forced to work faster.

In the first three years of life, the mass of the myocardium increases by 3 times, and by the age of 15 - by 10. In boys, its size is larger than in girls. At the same time, different parts of the heart grow unevenly:

• up to 2 years - mainly atria;
• 2-10 years - all departments;
• from the age of 11 - mainly the ventricles.

In children, it is optimal to study the pulse during sleep or rest, since the heart rate at this age is highly lability and can be greatly accelerated by excitement, minimal physical exertion, movements, after waking up, at an elevated temperature due to illness.

Technique for palpation of the pulse on the radial artery:

1. Heart rate is determined on both hands at the same time.
2. Grasp the patient's hands in the area of ​​the wrist joint so that the index, middle and ring fingers are on the radial artery.
3. The child should be calm, relaxed, hands are at the level of the heart without tension.
4. Using the tips of three fingers, gently press the artery against the radius and assess the main parameters.

Characteristics of the detected pulse:

1. Synchronization on both hands (if the indicators are the same, further research is carried out on one hand);
2. Frequency (not less than a minute due to high rhythm variability). Up to two years, heart rate is determined only with auscultation of the heart.
3. Rhythm. In healthy young children, physiological arrhythmias associated with breathing are observed (when breathing is delayed, the rhythm is restored).
4. Tension, fullness. These indicators indicate changes in blood pressure, the valvular apparatus of the heart, the strength of its contractions, and the volume of circulating blood.

It is important when examining the pulse in parallel to measure the heart rate by auscultation (in the heart).

Due to very strong sympathicotonia, premature babies are characterized by high lability of the pulse (from 120 to 200 beats / min.). The heart needs a longer adaptation, during which:

• myocardial contractility improves;
• energy costs are reduced;
• the level of blood pressure rises;
• the pathways of embryonic blood flow (the ductus arteriosus and the oval window) are closed;
• reduced resistance to blood flow in peripheral vessels.

Table of norms by age

Heart rate table for children from 0 to 18 years old:

A doctor treating children has a percentile table of heart rate norms by age on his desktop and, if necessary, verifies the readings with those obtained during the examination.

Heart rhythm disturbances in childhood are characterized by:

• the prevalence of functional arrhythmias (without organic damage to the myocardium);
• connection of rhythm disturbances with congenital heart defects;
• impulse formation disorders;
• paroxysmal seizures;
• rapidly developing cardiac decompensation and circulatory failure.

0-5 years old

The first months after birth, the baby's heart rate is the same as in the womb. The high pulse rate is mainly due to the sympathetic innervation of the heart.

A one-year-old child is characterized by sinus arrhythmia (pulse acceleration on inspiration and slowdown on expiration). This is the result of an increase in the tone of the vagus nerve and the intensity of the blood supply to the myocardium during certain phases of respiration.

Due to the high heart rate for newborns and young children, a shortening of the working cycle is characteristic (all changes in the myocardium during one systole and diastole). In babies, it decreases due to the relaxation phase of the ventricles. As a result, the cavities do not have time to fill with a large amount of blood. Therefore, due to tachycardia, the newborn's body is fully provided with oxygen and nutrients.

In early childhood, the most common:

1. Supraventricular heterotopic tachycardia. This is a high frequency atrial rhythm that occurs due to abnormal excitation of the myocardium. In 30-50% of children, by the age of 1.5 years, spontaneous recovery occurs due to the maturation of the structures of the cardiac conduction system.
2. Idioventricular rhythm. Observed in children with congenital heart defects and myocardial damage.
3. Atrial fibrillation.
4. Atrioventricular block II-III degree.
5. Ventricular arrhythmias.

5-10 years

At this age, the heart continues to gain mass intensively, the capacity of the ventricles increases, which provides a large ejection fraction. The regulation of the rhythm by the vagus nerve matures. As a result, the heart rate gradually slows down while maintaining the required minute blood volume. And the pulse rate in a 5-year-old child already ranges from 80 to 115 beats / min.

Rhythm disturbances are most often associated with the pathology of the automatism of the sinoatrial node, the prevalence of ectopic centers of excitation, incomplete conduction blocks.

In children of this age, the following are common:

1. Supraventricular tachycardia (closer to six years).
2. Sick sinus syndrome.
3. Non-paroxysmal tachycardia.
4. Atrioventricular blockade I-II degree.
5. Extrasystolic arrhythmias.

10-18 years old

With growing up, the rate of heart rate in children decreases. In adolescence, hormonal changes due to puberty and growth leaps, and an imbalance between the divisions of the autonomic nervous system cause functional rhythm disturbances. These are transient conditions, which are characterized by the absence of organic pathology of the pathways in the heart.

The main pulse disorders at this age:

1. Sinus tachy, bradycardia.
2. Paroxysmal supraventricular tachycardia.
3. Extrasystole.
4. Accelerated ectopic rhythm.
5. Atrial flutter.

When to Seek Medical Help - Alarming Symptoms

Although most rhythm disturbances in childhood are not dangerous, there is a risk of sudden paroxysms with the rapid development of heart failure, which pose a real threat to the child's life and require an immediate complex of urgent measures.

Pulse disorders indicate various diseases:

1. Congenital heart defects.
2. Myocarditis.
3. Cardiomyopathy.
4. Arterial hypertension.
5. Rheumatism.
6. Vegetative dysfunctions.
7. Intoxication.
8. Tumors of the heart.
9. Intracranial hypertension.
10. Endocrine diseases (thyrotoxicosis, hypothyroidism).
11. Anemia.
12. Fever.
13. Genetic pathologies.

The range of symptomatic manifestations of arrhythmias is incredibly wide - from asymptomatic disorders to clinical death.

Children of the first two years of life cannot explain what exactly worries them. Therefore, the main signs of a heart rate disorder that an infant gives are:

• anxiety, crying;
• lethargy, drowsiness;
• shortness of breath, wet cough (in severe cases with frothy sputum);
• loss of consciousness;
• blanching of the skin, sometimes with a cyanotic tinge;
• sweating;
• increased urination.

If a parent puts his hand on the baby's heart area, he will feel a fast, too slow and uneven pulsation.

In older children, the symptoms are:

• palpitations;
• a feeling of interruptions, fading in the work of the heart;
• dyspnea;
• violation of consciousness;
• fear, fright, depression;
• increased fatigue;
• headaches, vertigo;
• cardialgia.

Each child's heart rate is relative. This age is characterized by functional deviations from the set ones. Sinus bradycardia (decrease in heart rate by 15% compared to the norm) develops in healthy children with constitutional vagotonia or athletes.

Often, rhythm disturbances are not detected at a regular appointment with a pediatrician. Therefore, to determine the adaptation of the cardiovascular system to age standards at school or sports clubs, the doctor conducts special stress tests. The bottom line is to compare the heart rate at rest and immediately after dosed physical activity (squats, bends, exercise bike), after one and five minutes. The results obtained are substituted into the formula: the final coefficient corresponds to the group of physical education.

All children with persistent arrhythmia are exempted from physical education and participation in sports. A child with episodic disorders is shown a preparatory group throughout the year, then the main one.

Conclusions

Often, parents are concerned about a fast heartbeat in an infant, mistaking this for a pathology. The pediatrician will explain what the child's pulse should be, depending on age, and will notice the deviations in time.

For children with arrhythmias, a dispensary observation and rehabilitation program has been developed to prevent paroxysms and reduce the severity of seizures. It provides for a special day and study regimen, a favorable psychological microclimate in the family, balanced nutrition, and dosed physical activity.