premature infant

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Related to premature infant: recessive inheritance, dominant inheritance


a human child from birth (see newborn infant) to the end of the first year of life. Emotional and physical needs at this time include love and security, a sense of trust, warmth and comfort, feeding, and sucking pleasure.
Growth and Development. Development is a continuous process, and each child progresses at his own rate. There is a developmental sequence, which means that the changes leading to maturity are specific and orderly. The various types of growth and development and the accompanying changes in appearance and behavior are interrelated; that is, physical, emotional, social, and spiritual developments affect one another in the progress toward maturity.

Development of muscular control proceeds from the head downward (cephalocaudal development). The infant controls the head first and gradually acquires the ability to control the neck, then the arms, and finally the legs and feet. Movements are general and random at first, beginning with use of the larger muscles and progressing to specific smaller muscles, such as those needed to handle small objects. Factors that influence growth and development are hereditary traits, sex, environment, nationality and race, and physical makeup. See also growth.
large-for-gestational-age infant a preterm, term, or postterm infant who is above the 90th percentile for gestational age in head circumference, body weight, or length.
low-birth-weight infant one that weighs less than 2500 grams at birth. This standard is routinely used for infants in developed countries, but infants born in other countries typically weigh less at birth. In India the criterion for normal birth weight is 2150 grams and in Malaysia it is 2000 grams.
newborn infant a human infant from the time of birth through the 28th day of life. At birth, the gestational age as well as birth weight is assessed and the newborn classified accordingly; for example, large for gestational age, preterm (premature), or low birth weight. Called also neonate and newborn.
premature infant (preterm infant) one born before a gestational age of 37 completed weeks (259 days). The duration of gestation is measured from the first day of the last menstrual period and is expressed in completed days or weeks.
postmature infant (postterm infant) one born any time after the beginning of the forty-second week (288 days) of gestation.
small-for-gestational-age infant a preterm, term, or postterm infant who is below the 10th percentile for gestational age in head circumference, body weight, or length.
term infant one born at a gestational age of 37 to 42 completed weeks (259 to 293 completed days).
very-low-birth-weight infant one that weighs less than 1000 grams at birth.
Patient Care. Low-birth-weight and very-low-birth-weight infants require special care and support, preferably in a neonatal intensive care unit (NICU), until sufficient weight is gained and the infants have matured and are able to thrive without elaborate support systems.

At the time of delivery, whether cesarean or vaginal, a skilled neonatal team should be present to provide immediate care. After resuscitation measures under a radiant warmer are completed and the newborn is stabilized, transfer to the NICU is done without interruption of warming and oxygen therapies.

Among the problems associated with low birth weight are hypothermia, respiratory distress, hyperbilirubinemia, fluid and electrolyte imbalance, susceptibility to infection, and feeding problems.

Very-low-birth-weight newborns and infants are at significant risk for hypothermia because of their small body mass, large surface area, thin skin, minimal subcutaneous tissues, and posture. Thermoregulation is provided through the use of a standard incubator or a radiant warmer. Radiant warmers have the advantage of accessibility for caregivers and improved visibility of the infant. Their chief disadvantage is increased insensible water loss.

Neonatal respiratory distress syndrome is the major cause of death in newborns. Atelectasis can lead to hypoxemia and elevated serum carbon dioxide levels and all the problems related to inadequate gas exchange. Oxygen therapy must be administered with caution because of the danger of retinopathy.

The treatment of hyperbilirubinemia remains a challenge because of lack of consensus on the level of serum bilirubin concentration at which therapy should begin, the uncertain diagnosis of kernicterus, and the currently limited knowledge of the blood--brain barrier. It is believed that these infants are at critical risk for bilirubin-related brain damage at serum concentrations as low as 6 to 9 mg/dl. Phototherapy is the treatment of choice and may be given prophylactically in some institutions to all infants weighing less than 1000 grams.

The management of fluid and electrolyte administration to maintain proper balance is highly complex. Factors taken into consideration are proportion of body, composition of water, renal function, and insensible water loss. Fluid and electrolyte status must be closely monitored. Overhydration is a hazard because it has been implicated in the development of such serious complications as pulmonary edema, patent ductus arteriosus, and necrotizing enterocolitis in these infants.

Low-birth-weight and very-low-birth-weight infants are particularly susceptible to infection because their immunologic system is deficient. Additionally, equipment and care related to long-term respiratory and nutritional support, together with frequent laboratory testing, increase exposure to infectious agents. Infection control measures must be adhered to faithfully. In some NICUs reverse isolation is required for all infants weighing less than 1000 grams.

Since the skin of these infants is highly permeable and easily traumatized, every effort must be made to preserve its integrity. Routine care to preserve the integrity of the skin, caution in the use of topical ointments and antiseptic preparations, and minimal handling also are essential.

At the beginning, nutritional support in the form of total parenteral nutrition may be necessary until enteral feedings are feasible. Oral feedings usually are initiated by the end of the first week of life. Continuous gastric feedings via infusion pump have the advantage of preventing vomiting and aspiration and abdominal distention associated with intermittent feedings of larger amounts. The enteral feedings given in this manner include breast milk (donor or mother) and special formulas.

Discharge planning and follow-up care are begun upon admission to the NICU. Individual family needs should be assessed and available community resources identified. Parental education and support are provided throughout the time the infant is in the NICU. At the time of discharge parents should be confident of their ability to care for the infant, knowledgeable about sources available to them, and able to utilize those resources to the fullest.

premature infant

any neonate, regardless of birth weight, born before 37 weeks of gestation. Because exact gestational age is often difficult to determine, low birth weight is a significant criterion for identifying the high-risk infant with incomplete organ system development. Predisposing factors associated with prematurity include multiple pregnancy, toxemia, chronic disease, acute infection, sensitization to blood incompatibility, any severe trauma that may interfere with normal fetal development, substance abuse, and teenage pregnancy. In most instances the cause is unknown. The incidence of prematurity is highest among women from low socioeconomic circumstances, for whom poor nutrition and lack of prenatal medical care are often precipitating factors. The premature infant usually appears small and scrawny, with a large head in relation to body size, and weighs less than 2500 g. The skin is thin, smooth, shiny, and translucent, with the underlying vessels clearly visible. The arms and legs are extended, not flexed, as in the full-term infant. There is little subcutaneous fat, sparse hair, few creases on the soles and palms, and poorly developed ear cartilage. In boys the scrotum has few rugae, and the testes may be undescended; in girls the labia gape and the clitoris is prominent. Among the common problems of the premature infant are variations in thermoregulation, chilling, apnea, respiratory distress, sepsis, poor sucking and swallowing reflexes, small stomach capacity, lowered tolerance of the alimentary tract that may lead to necrotizing enterocolitis, immature renal function, hepatic dysfunction often associated with hyperbilirubinemia, incomplete enzyme systems, and susceptibility to various metabolic upsets, such as hypoglycemia, hyperglycemia, and hypocalcemia. The degree of complications and the rate of survival of premature infants are directly related to the state of physiological and anatomical maturity of the various organ systems at the time of birth, the condition of the infant other than prematurity, and the quality of postnatal care. With treatment in a neonatal intensive care unit, survival rates improve yearly. In increasing numbers of very small babies, development is normal, and those who do not have seizures or apneic spells in the first few days are unlikely to suffer neurological or physical sequelae of their prematurity. Of primary concern for the nurse caring for the premature infant are the stabilization of body temperature by maintaining a neutral thermal environment, the maintenance of respiration, the prevention of infection, the provision of adequate nutrition and hydration, and the conservation of energy. Important functions of the nurse are to involve the parents in the care of the infant, to explain therapeutic procedures, and to facilitate attachment between the infant and family. Also called
Usage notes: (informal)
preemie, preterm infant. Compare postmature infant.
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Premature infant

premature infant

Prematurity, premie; preterm infant Obstetrics An infant born before the 37th wk of gestation and after the 20th wk, who weighs 500–2500 g. See Very-low birth weight.

pre·term in·fant

(prē'term in'fănt)
An infant with gestational age of fewer than 37 completed weeks (259 completed days).
Synonym(s): preemie, premature infant, premature newborn, preterm newborn.
References in periodicals archive ?
The problem of premature lungs sticking to themselves internally has basically been solved, so most extremely premature infants now survive their initial lung disease.
The epidemic of blindness that occurred 40 to 50 years ago due to the use of oxygen in treating premature infants is well known.
Partnership with Prolacta Bioscience Ensures a Safe, Standardized, and Steady Supply of Pasteurized Donor Milk to Meet Feeding Needs of Premature Infants throughout BayCare Health System
Data suggest that AEROSURF may be reducing the incidence of nCPAP failure, which occurs when premature infants initially treated with nCPAP alone, require delayed surfactant therapy by means of invasive endotracheal intubation.
Hanson-Abromeit explains that premature infants are overwhelmed with information: noise, light, new people.
In the first open trial, 12 formula-fed premature infants were randomly assigned to receive increasing doses of either formula + Binf or formula + Blac for 5 weeks.
7 ( ANI ): Scientists have claimed that the benefits that premature infants gain from skin-to-skin contact with their mothers is measurable even 10 years after birth.
Premature infants lack the tactile stimulation they would have otherwise experienced in the womb.
Premature infants often suffer from respiratory problems due to their underdeveloped lungs.
Stronger EEG traces were seen for premature infants who had been in hospital for at least 40 days than for non-hospitalised babies of the same age.
In premature infants, however, it frequenlty fails to close resulting in further impairment in lung and heart function.