Sleep in children

A child's sleep is a natural component of his physiological activity, ensuring a normal rhythm of the processes of higher nervous activity, metabolic processes, physical development, growth and maturation.

Being a definite result of the previous period of wakefulness, the dream that replaces this waking becomes a pledge or condition for ensuring the normal vital activity of the child in the subsequent wakefulness. Hence it follows that inadequately organized wakefulness or illness of the child can lead to a violation of the usefulness and effectiveness of sleep, and sleep disturbances cause the child's insufficient activity during wakefulness. Both can be the reason for a significant delay in the neuropsychic and physical development of children, and with prolonged preservation leads to the appearance of diseases. Therefore, monitoring the organization of a child's sleep, the characteristics of falling asleep, sleeping at night and waking up is an important part of the overall pediatric observation. Sleep disorders can be the basis for an in-depth examination of children.

In a newborn child, sleep has a so-called polyphasic character, that is, it occurs many times during the day and night. So, during the day the newborn child falls asleep 4 to 11 times, and the real differences of day and night in the duration of sleep have not yet been established. Over the years, there has been a change in polyphasic sleep to monophasic, with only hidden polyphasic elements retained in older children and adults.

A distinct predominance of night sleep occurs at the end of the first month and after that stabilizes. In general, the natural need for sleep decreases with age.

Need for sleep in young children, h

Age	Total per day	At night	In the afternoon
1 week	16.5	8.5	8
1 month	15.5	8.5	7th
3 months	15	9.5	5.5
6 months	14.25	Eleven	3.25
9 months	14	11.25	2.75
12 months	13.75	11.25	2.5
18 months	13.5	11.25	2.25
2 years	13.25	Eleven	2.25
3 years	12	10.5	1.5
4 years	11.5	11.5	-
5 years	Eleven	Eleven	-
6 years	10.75	10.75	-
7 years	10.5	10.5	-
8 years	10.25	10.25	-
9 years	10	10	-
10 years	9.75	9.75	-
11 years	9.5	9.5	-
12 years	9.25	9.25	-
13 years	9.25	9.25	-
14 years	9	9	-
15 years	8.75	8.75	-
16 years	8.5	8.5	-
17 years	8.25	8.25	-
18 years	8.25	8.25	-

With a certain decrease in the total daily duration of sleep in children, this decrease occurs primarily due to hours of daytime sleep. Already at the end of the first year of life the child falls asleep in the day no more often 1 -2 times. From 1 1 / 2-2 years, the duration of a day's sleep is about 2 1/2 hours, and about an hour goes on falling asleep. After 4 years, not all children can save daytime sleep. Here individual differences in the need for sleep significantly affect. However, it is desirable that daytime sleep is provided to all children up to 5-6 years of age.

A calm sleep of normal duration, short periods of transition from wakefulness to sleep, and vice versa (no more than 30 minutes) are evidence of the health of the child, the normal mode of life, and a good psychological climate in the family.

[1], [2], [3], [4], [5], [6]

Electrophysiological Offensive of Sleep in Children

• the disappearance of a-activity on the EEG and its replacement by the low-latency activity of the mixed frequency;
• the appearance of slow movements of eyeballs on the electrooculogram;
• reduction of muscle tone on the electromyogram;
• generalized or local involuntary muscular contractions (electromyogram) - hypnotic myoclonus.

There are two qualitatively different phases of sleep:

1. orthodox sleep, the phase of slow sleep (FMS);
2. paradoxical sleep, fast sleep phase (FBS), or REM.

It is believed that 3 groups of neurons participate in the regulation of the cyclic phases of sleep.

The aminergic system (serotonergic + noradrenergic), or REM-off cells.

Cholinergic reticular system, or REM-on cells.

Separate phases and stages are best distinguished by their encephalographic characteristics:

• I stage - a nap with the gradual disappearance of a-rhythm;
• II stage - the appearance of a specific for this phase of encephalographic activity - the spindles of sleep, with a slowing of the pulse, decreasing breathing, relaxation of the muscles;
• III and IV stages - stages of deeper sleep, characterized by the appearance of high-amplitude 8-activity, an increase in heart rate.

[7], [8], [9]

Phase of fast sleep in children

The phase of fast sleep is characterized by a fast desynchronized EEG, which is characteristic of intense wakefulness, although the child is in a state of deep sleep. In this stage rapid eye movements, low tone of skeletal muscles and the greatest instability of vegetative functions are noted - arrhythmia of cardiac activity, up to short-term asystole, arrhythmia of respiration, falling of arterial pressure. In the fast sleep phase, active mental activity is also marked - bright dreams experienced.

At all age stages, sleep is organized cyclically, that is, successive stages of slow sleep terminate in a phase of fast sleep. A few full cycles are observed during the night.

The change in the structure and duration of deep sleep can be ascertained by a characteristic such as the number of movements in a dream. The child of the first years of life has more than the older children (80 to 60), but the abundance of movements in a dream does not prevent the younger from sleeping, and often leads to the awakening of the older child.

The phase of fast sleep is characterized by physiological myoclonus - small fast twitching of individual muscle beams and groups with minor movement in small joints, such as twitching of the fingers and facial muscles. In stages of slow sleep, myoclonus is significantly less.

The first period of FBS is noted in 70-100 minutes from the onset of sleep. The EEG picture at this phase resembles that observed in the first stage of FMS, but often it appears waves like the saw's teeth.

The phases of slow and rapid sleep alternate throughout the entire sleep time at intervals of 90-120 minutes. At the age of 2-3 years, the duration of one cycle of sleep is about 60 minutes and the first episode of FBS is observed 1 hour after the child falls asleep. By 4-5 years, the cycle can last up to 90 minutes and during the entire sleep period, about 7 cycles are recorded, which is almost identical to that of an adult.

The phase of slow sleep in the child

The phase of slow sleep acquires significance in the overall structure of sleep after 36 weeks of gestation, but has very little duration. In a newborn child with normal gestation, FBS, FMS and undifferentiated sleep are identified. FBS can be recognized by sucking movements, almost continuous body movements, tremors, grimaces and even elements of walking, irregular breathing, coinciding with flashes of muscle activity. FMS is characterized by minimal motor activity and a higher muscle tone.