Nurse Alert When evaluating developmental accomplishments, the newborn should be assessed based on chronological age from expected date of birth from conception, not actual date of birth.
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䊋 Respiratory system:
• The premature newborn has low amounts of surfactant, resulting in alveoli that collapse easily and leading to poor gas exchange and decreased oxygenation, hypoxia, and poor activity tolerance due to low oxygen reserves. Respiratory distress syndrome (RDS) can result and requires intensive treatment (see Chap. 12: Newborn Care).
• Increased flow of blood back into the lungs through the ductus arte- riosus, which fails to close after birth because oxygen levels and prostaglandin E levels do not increase sufficiently to stimulate vaso- constriction of the ductus arteriosus. A resulting pulmonary conges- tion, carbon dioxide retention, bounding femoral pulses, and increased respiratory effort are noted. Pulmonary dysfunction can become chronic.
• Apnea of prematurity (cessation of breathing for up to 20 seconds or less than 20 seconds, accompanied by bradycardia, cyanosis, or pal- lor) may be noted secondary to immature neurologic control of res- pirations, or obstruction from structural collapse or secretions.
䊋 Poor temperature control:
• High body surface for low body weight, which provides high loss of heat with lower heat production resulting in newborn hypothermia.
• Decreased subcutaneous fat, resulting in minimum insulation and increased loss of body heat from blood vessels that are close to the skin surface.
• Thin skin with high permeability, leading to water loss and heat loss.
• Premature newborn posture with less flexion and greater extension of limbs leads to greater exposure of body surface area and greater heat loss.
• The newborn’s ability to vasoconstrict blood vessels is decreased, causing a decreased ability to conserve body heat.
䊋 Gastrointestinal (GI) problems:
• Aspiration due to poor gag, sucking, and swallowing reflexes caused by a weak esophageal sphincter.
• High caloric and fluid demand with small size but small stomach capacity requiring frequent feedings and supplements.
• Increased metabolic rate and oxygen demands due to energy required for sucking, and low activity tolerance and easy fatigue.
• Limited ability to process nutrients including conversion of amino acids, absorption of fats (low bile salts), or digestion of lactose (needs simple sugars).
• Calcium and phosphorus levels are low because stores are usually built up in the last trimester. Bone demineralization may be noted.
• Decreased tissue perfusion to the GI tract or hypoxemia at birth may result in feeding intolerance and necrotizing enterocolitis.
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䊋 Decreased renal function:
• Low glomerular filtration rate due to low renal blood flow and hypoxia resulting in oliguria or anuria
• Limited ability of the preterm infant’s kidneys to concentrate urine, leading to excretion of excess fluid and risk for dehydration
• Excretion of glucose by the immature kidneys, leading to hypo- glycemia
• Decreased ability of the kidneys to buffer, with excess excretion of bicarbonate and resulting metabolic acidosis
• Decreased ability of premature kidneys to excrete drugs, leading to toxicity of drugs at lower levels and high susceptibility to nephro- toxic drugs
䊋 Altered immune system:
• High risk for infection because passive immunity gained from mother usually is received by the fetus in the last trimester.
• Preterm skin surface provides less defense against invading organisms.
• IgA, a significant immunoglobulin needed by the newborn that is acquired through breast milk only, does not cross the placenta;
thus, the premature newborn must have breast milk to gain this protection.
䊋 Neurologic system:
• Myelination of nerves occurs beginning with the second trimester until birth. The closer to term the fetus is, the less disruption of neu- rologic function is noted.
• Intracranial hemorrhage and intraventricular hemorrhage (with pos- sible hydrocephalus) are the most common complications of preterm infants. The fragile vasculature of the brain easily ruptures in the presence of hypoxia, as commonly occurs with birth asphyxia or birth trauma.
• Preterm newborns have different response patterns than term new- borns with fewer reactive periods, decreased responsiveness, and weaker muscle tone. The pattern can be used to determine the best times for feeding and bonding.
TREATMENTS
䊋 Radiant warmer or incubator to assist with temperature control.
䊋 Dietary support with breast milk and special preterm formula with extra protein and calories. Additional support includes the following:
• A diet high in polyunsaturated fat (well tolerated by preterm new- born)
• Multivitamin supplementation of vitamins A, D, E, and iron
• Calcium, phosphorus, and vitamin D supplements for bone mineral- ization
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• Oral (breast/bottle), naso/orogastric gavage, or total parenteral nutri- tion provided for nutritional support based on the infant’s ability to tolerate nutrition
䊋 Fluid replacement: There is an increased need for this if radiant warmer is used to maintain temperature.
䊋 Follow-up treatment for long-term needs:
• Neurologic deficits, such as lower IQ, seizures, and palsy, are diffi- cult to predict and highly influenced by the family support system and socioeconomic status (resources).
• Speech deficits.
• Retinopathy.
• Bronchopulmonary dysplasia (due to damaged alveoli).
• Auditory defects.
NURSING INTERVENTIONS
䊋 Support fetal respiratory status, note respiratory distress, and provide oxygen if ordered.
䊋 Maintain warm environment to prevent cold stress.
䊋 Initiate feeding as quickly as possible and schedule frequent feedings.
䊋 Plan activities to avoid fatigue.
䊋 Encourage contact between the newborn and the parents and family.
䊋 Monitor the newborn’s breath sounds and pulse oximetry.
䊋 Monitor vital signs.
䊋 Assess temperature via axillary route every 4 hours.
䊋 Monitor for skin breakdown.
䊋 Provide family teaching regarding the need for ongoing monitoring of growth and development with appropriate support for the family and the infant if developmental delay is noted.