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Zykova I.N. neonatologist

 

Definition of Conception “Prematurely Born Child”, Degrees and Signs of Prematurity. Maturation of Prematurely Born Children’s Sense Organs. Characteristics of Prematurely Born Children’s Neonatal Period. Conditions for Nursing of Prematurely Born Children.

 

  

Infants who are born before full full term, less than 260 days, or 37 weeks a by definition, born prematurely.

  • 1st degree: 35-37 weeks of gestation, weight 2001-2500 grams, (70-88oz, 4.4-5.5 lbs).
  • 2nd degree: 32-34 weeks of gestation, weight 1501-2000 grams, (53-70oz, 3.3-4.4 lbs).
  • 3rd degree: 29-31 weeks of gestation, weight 1001-1500 grams, (35-53oz, 2.2-3.3 lbs).
  • 4th degree: less than 29 weeks, weight less than 1000 grams, (<35oz, <2.2 lbs).
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It is important to note that while the conventionally accepted degrees of prematurity are grouped by weight, this method of classification is used for the standardization of observation and treatment and to support statistical analysis. Birth weight doesn’t always provide an accurate indication of a newborn’s developmental age and degree of prematurity.

 

Cases of newborns with higher weight and height, that also evidence symptoms of prematurity, are well documented. In these cases, clinicians are required to perform thorough testing of the infant in order to make an accurate assessment which degree of prematurity present.

 

Prematurely born infants exhibit the following features: Weak crying, superficial and diminished irregular breathing, inadequate development of subcutaneous fat; red, dry and wrinkled skin which is covered with lanugo. Every fotanelle is opened, soft auricles, which are pressed close to the head. The nails do not reach to the edge of finger bones. An umbilicus is situated below the middle of the body length. Genitals are underdeveloped. (Boys have undescended testis and labia minora are not covered with labia majora. Their movements are poor. Hypomyotonia (weak muscular tonicity) is usually present. Physiological reflects are reduced. Sucking and swallowing reflects can also be absent.

 

Maturation of Prematurely Born Children’s Sense Organs.

 

Touch: Between 8 and 15 weeks' gestational age (GA), the fetal somatosensory system (senses of touching, temperature and pain) develops in a cephalocaudal pattern. By 32 weeks' GA, the fetus consistently responds to temperature, pressure, and pain.

 

Taste: Taste buds are morphologically mature by 13 weeks' GA. By 24 weeks' GA, gustatory responses may be present.

 

Hearing: Auditory function begins at 20 weeks' GA. A fetus is capable of responding to sound by 25 weeks' gestation. All major auditory structures are in place at this time. Both cortical and brain stem auditory-evoked responses can be elicited at 24-28 weeks' gestation, although the morphology and latency is different than in the term infant. Sensitivity and frequency resolution approach adult level by 30 weeks' GA and are indistinguishable from the adult by term.

 

Sight: Vision is the last sensory system to develop in a fetus. All major structures and visual pathways for vision are complete by 24 weeks' gestation. Visual evoked responses (VERs) have been elicited (but with prolonged latency) as early as 24 weeks' gestation. Pupillary response to light appears as early as 29 weeks' GA and is present consistently by 32 weeks' GA. By 36 weeks' gestation, the VER is similar to that of an infant carried to term. The vision of a full-term child is 20 times less than the vision of an adult. A newborn infant's vision is blurred. A newborn infant sees only outlines of objects (subjects) which are situated at a distance of 25-30 centimetres from the eyes and distinguishes only shiny or red objects (subjects).

 

Smell: By 28-32 weeks' GA, premature infants appear to respond to concentrated odor.


Characteristics of Prematurely Born Children’s Neonatal Period.


Prematurely born children, especially children with a birth weight less than 1500 grams, require continual monitoring and special attention, because a range of problems may appear while taking care of them.

A neonatal period, which full-term infants and preemies experience, lasts 28 days after their birth. During a neonatal period some physiological events within every child occur regardless of whether he or she is a full-term baby or a preemie.

Prematurely-born children’s neonatal period has some unique features, and these features depend on the degree of newborn maturation.

Sluggishness, sleepiness, and a weak cry are typical for preemies. Physiological erythema (red color of their skin) is sharply expressed.

Preemies’ physiologic jaundice can be visible later because of bright skin coloring. It often lasts longer than full-term babies' physiological jaundice and can linger for up to 3-4 weeks of their lives.

A prematurely-born child’s umbilical cord is thick and juicy, which causes it to take longer to dry and fall off, as long as 14 days after birth.

The resulting wound is also slow to heal. At 1-2 weeks of age most preemies have edema around the legs and abdomen.

Preemies are not able to regulate their own temperature well. Thermoregulation is not stable. It is very easy to overcool and overheat a preemie. “Fever in an overheated incubator” is not an unusual event.

Respiratory rate is variable and can reach up to 60-80 breaths per minute. While sleeping, pauses in breathing (apneas) often take place. Apneas are observed during periods of feeding as well. Preemies often have a partial atelectasis (collapse) of their lungs.

Heart sounds are muffled, and the cardiac rhythm can change depending on conditions and the child’s status. Preemies’ heart rate can increase up to 200 beats per minute during periods of anxiety and increased temperature.

Physiological weight loss is restored by the second or third week, which is much longer in comparison with full-term babies. Weight gain at the end of the first month is minor and accounts for 100-300 grams.

By the second or third month of life prematurely-born children start growing intensively and often have anemia. When hemoglobin falls below 50 grams per liter, such anemia requires special treatment. Over the course of time, with a balanced nutrition containing enough proteins and vitamins, the anemia disappears.

Prematurely-born children require special attention, because a range of problems may appear while caring for them. First of all, this applies to children with a birth weight less than 1500 grams (very low birth weight), and especially with a birth weight less than 1000 grams (extremely low birth weight).

In developed countries premature infants are usually cared for in a neonatal intensive care unit (NICU). The physicians who specialize in the care of very sick or premature babies are known as neonatologists.

Treatments may include fluids and nutrition through intravenous catheters, oxygen supplementation, mechanical ventilation support, and medications. Bili lights may also be used to treat newborn jaundice.

 

Also noteworthy is the artificial feeding of premature infants. Children up to 33-34 weeks of gestation, as a rule, are fed with the help of a naso-gastral or oro-gastral tube, which is placed into the stomach.

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This is because sucking and swallowing reflexes are either reduced or absent. Besides, coordination of these reflexes is required for successful independent feeding. This coordination develops only after 33-34 weeks of gestation. Expressed breast milk and/or infant formula serves as food for such babies. The part of the nourishment which children don’t assimilate due to the reduced activity of digestive enzymes and other functional and morphological features of prematurely-born child’s digestive system is injected intravenously as separate solutions of proteins, fats and carbohydrates (parenteral feeding).

 

Modern neonatal intensive care involves the sophisticated measurement of temperature, respiration, cardiac function, oxygenation, and brain activity.

Edited by Peter Cebull

 

Conditions for Nursing of Prematurely Born Children.

The survival of low-birth-weight infants depends on a number of external factors. They require ideal conditions and care of optimal quality to reduce their mortality rate and ensure their future development.

One of the most important conditions of nursing prematurely born infants is an optimal temperature regime. Children with a birth weight less than 1500 grams are put into incubators. If a child keeps heat poor, then he or she can be put into an incubator as well, though his or her weight may be more than 1500 grams.

 

Just after birth children need a temperature 34-35.5 Celsius degrees in an incubator (the less mass of a child the higher temperature). By an end of the first month the temperature has to be gradually reduced up to 32 Celsius degrees. Temperature regime must be chosen individually. Special sensors serve to control the body’s temperature. Sensors are connected to the infant and can be observed by a monitor.

 

Special tables with heat sources can be used instead of incubators. High humidity is also an important condition for nursing prematurely born infants. For the first few days of an infant's life, humidity should reach 70 - 80%. For this purpose special humidifiers exist in incubators.

Developmental care such as paying attention to light, sound, handling, and touch in the neonatal intensive care unit (NICU) can improve the medical outcome of critically ill infants. Therefore a prognosis of psychomotor development improves.

Understanding infant vulnerabilities and responses to stress can lead to a systematic method to support the infant's strengths to alleviate the stress response. Calm infants require less oxygen (and fewer changes in mechanical ventilation), expend less energy, have improved feeding tolerance, and have a shortened duration of hospitalization.

 

Including parents as part of the care team reduces infant pain and stress and improves the medical outcome. Also pay attention to infant responses or cues. Premature infants who shield their face with their hands are not saying hello; they are letting you know they have had enough stress.

The senses continue to develop in the NICU, beginning with touch and ending with vision. Neuronal connections will be affected by negative and positive environmental influences.

Neuronal changes occurring during 23-40 weeks' gestation, while a prematurely born child is in the NICU, include the following:

  • Cell migration 
  • Cell differentiation 
  • Myelination 
  • Reorientation of cells 
  • Axonal growth 
  • Apoptosis 
  • Cell proliferation 
  • Formation of dendrites 
  • Formation of synapses
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During this critical period of brain development, sensory and environmental influences can regulate wiring of neuronal networks, which can be permanently altered by early abnormal sensory input.

 

In addition to light and sound, NICU medical and nursing procedures necessary to ensure the infant's survival are by nature stressful. Suctioning, chest physical therapy, gavage tube insertion and feeding, intravenous line placements, chest radiographs, ultrasound studies, ophthalmologic examinations, daily physical examinations, frequent assessments of vital signs, bathing, and weighing have all been shown to cause significant stress in preterm or critically ill infants.

 

It has been estimated that a critically ill infant is handled or manipulated for monitoring or other therapeutic procedures more than 150 times per day with <10 minutes of uninterrupted rest.

Infant developmental care is care responsive to an individual infant's developmental needs. The key components are as follows:

  • Management of the environment: Decreasing noise and visual stimulation, providing appropriate bedding. 
  • Collaboration with parents and promotion of infant-parent bonding. 
  • Activities that promote self-regulation and state regulation: Nonnutritive sucking, kangaroo care, cobedding of multiples. 
  • Fixed midline positioning and containment. 
  • Clustering of care: To promote rest.

Preterm infants are at risk for sensorineural hearing loss, which occurs at a rate of 10% compared with 0.5% for term infants. Noise may interfere with the development of auditory pathways necessary for communication and language skills. Premature infants are at risk for auditory processing deficits such as speech sound discrimination and other disorders of syntax, semantics, and auditory memory.

 

The recommended light (<60 fc) and sound standards (<50 dB) (speech in a low voice) decrease hearing loss and poor developmental outcome in critically ill infants. In the NICU both parents and personnel need to speak in a low voice, and refrain from knocking on surfaces, especially the sides and doors of an incubator.

A premature infant is unable to guard against light exposure and requires shielding from the common sources of light in the NICU. At least 38% of white light can penetrate the eyelids and disturb an infant. There is also concern that excess light exposure at 32-40 weeks' gestational age may lead to sensory interference. Sensory interference may occur when immature sensory systems are stimulated out of order or are bombarded with inappropriate stimuli. nedonoshenniy

Premature infants are very sensitive to what they perceive as noxious touch. When they experience these events they respond with tachycardia, agitation, hypertension, apnea, a decrease in oxygen saturation, disorganization, and sleep deprivation.

 

A premature infant is unable to sustain physiologic and behavioral responses to pain for prolonged periods. Infant pain scales may not be as clinically useful because the responses may be dampened or may not be identified by caregivers.

In one study, three of four hypoxic or oxygen-desaturation episodes in preterm infants were associated with caregiving procedures. Similarly, increased concentrations of stress hormones have been observed in association with routine nursing procedures.

Premature infants who shield their face with their hands are not saying hello; they are letting you know they have had enough stress.

It is very important to try to reduce stress and the number of painful procedures.

Nonpharmacologic treatments to reduce pain and stress in infants include behavioral and environmental strategies such as non-nutritive sucking, administration of sucrose, swaddling and containment, attention to sound and light, limiting environmental stressors such as clustering of care, and allowing for rest periods.

 

Correcting Position of Prematurely Born Children.

It is important to provide a prematurely born child with boundaries (“nest”).  

Synaptic connections are stimulated with repeated use, and they weaken with disuse. Once outside the womb, the loss of uterine containment cannot support muscular development. A weak, premature infant is unable to counteract the effects of gravity and assumes a flattened posture with extremity extension, abduction, and external rotation on the bed surface. Over time, this position will lead to abnormal developmental tone and positional deformities.

 

Premature infants in the womb are buoyant and turn easily, equalizing pressure stimuli. In the NICU, the impact of gravity inhibits any movement by the infant, who must rely on caregivers for proper positioning. Infants who are not turned are fixed in one position for prolonged periods and are at risk for development of muscular skeletal deformities that negatively affect the infant's future motor development and ability to explore, play, and develop social and other skills.

 

A progressive lateral flattening of the skull, called scaphocephaly or dolichocephaly, results in a narrow and elongated infant head. This occurs because the skull of the premature infant is thinner, softer, and at greater risk for postural deformities. Although this deformity appears to have no effect on brain development, lateral flattening has implications for infant attractiveness and may affect parental social attachment. With good care, this appearance can be significantly minimized.

 

A premature infant needs to be placed in a coiled position and moved from side to side regularly. Sometimes, under monitoring and control of a staff, a premature infant can be placed in a prone position.

 

 

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