Classification of High-Risk Infants - High-risk infants can be classfied according to size or age.

Classification According to Gestational Age

• Preterm (premature): An infant born before completion of 37 weeks of gestation

• Late preterm: An infant born from 34 {0/7} through 36 {6/7} weeks of gestation

• Early term: An infant born from 37 {0/7} through 38 {6/7} weeks of gestation

• Full term: An infant born from 39 {0/7} weeks through 40 {6/7} weeks of gestation

• Late-term: An infant born from 41 {0/7} through 41 {6/7} weeks of gestation

• Post-term (postmature): An infant born at 42 {0/7} or more weeks of gestation

Late Preterm Infants

LPIs are those born between 34 {0/7} and 36 {6/7} weeks of gestation. When compared with term infants, LPIs are at increased risk for problems with thermoregulation, hypoglycemia, hyperbilirubinemia, feeding, sepsis, and respiratory.

Classification According to Size

• Low–birth-weight (LBW) infant: An infant whose birth weight is less than 2500 g (5.5 lb), regardless of gestational age

• Very low–birth-weight (VLBW) infant: An infant whose birth weight is less than 1500 g (3.3 lb)

• Extremely low–birth-weight (ELBW) infant: An infant whose birth weight is less than 1000 g (2.2 lb)

• Appropriate for gestational age (AGA) infant: An infant whose birth weight falls between the 10th and 90th percentiles on intrauterine growth curves

• Small for date (SFD) or small for gestational age (SGA) infant: An infant whose rate of intrauterine growth was slow and whose birth weight falls below the 10th percentile on intrauterine growth curves

• Large for gestational age (LGA) infant: An infant whose birth weight falls above the 90th percentile on intrauterine growth curves

• Intrauterine growth restriction (IUGR): Found in infants whose intrauterine growth does not reach the expected potential

• Symmetric IUGR: Growth restriction in which the weight, length, and head circumference are all affected

• Asymmetric IUGR: Growth restriction in which the head circumference remains within normal parameters while the birth weight falls below the 10th percentile

The large for gestational age (LGA) infant is defined as weighing 4000 g (8.8 lb) or more at birth. An infant is considered LGA despite gestation when the weight is more than the 90th percentile on growth charts or two standard deviations greater than the mean weight for gestational age. The infant is at greater risk for birth injuries, asphyxia, and congenital anomalies such as heart defects.  At birth the typical LGA infant has a round face, a chubby body, and a plethoric or flushed complexion. The infant has enlarged internal organs (hepatosplenomegaly, splanchnomegaly, cardiomegaly) and increased body fat. The placenta and umbilical cord are larger than average. Insulin is considered the primary growth hormone for intrauterine development.

Discharge planning for the high-risk newborn begins early in the hospitalization. It includes:

• Infant care

• Durable medical equipment

• Appropriate immunizations

• Metabolic screening

• Hematologic assessment (bilirubin risk as appropriate)

• Hearing evaluation

• Instruction in CPR

The preterm infant is likely to have difficulty making the pulmonary transition from intrauterine to extrauterine life. Numerous problems can affect the respiratory systems of preterm infants:

• Decreased number of functional alveoli

• Deficient surfactant levels

• Smaller lumen in the airways

• Greater collapsibility or obstruction of respiratory passages

• Insufficient calcification of the bony thorax

• Weak or absent gag reflex

• Immature and friable capillaries in the lungs

• Greater distance between functional alveoli and the capillary bed

Infants normally breathe between 30 and 60 times/min. Signs of respiratory distress include:

• Flaring of the nares

• Expiratory grunt

• Retractions can begin as subcostal, suprasternal, or intercostal

• Compromised infant’s color progresses from pink to circumoral cyanosis and then to generalized cyanosis

Periodic breathing is a respiratory pattern commonly seen in preterm infants. This pattern is characterized by a 5- to 10-second respiratory pauses followed by 10 to 15 seconds of compensatory rapid respirations. Periodic breathing should not be confused with apnea. Apnea is classified as a cessation of breathing of 20 seconds or greater, or a shorter pause accompanied by bradycardia, cyanosis, or hypotonia.

Resporatory Complications:  Respiratory Distress Syndrome (RDS)

Respiratory Complications:  Bronchopulmonary Dysplasia

Persistent Pulmonary Hypertension of the Newborn (PPHN) is the combined findings of pulmonary hypertension, right-to-left shunting, and a structurally normal heart. It can occur either as a primary problem or secondary to Meconium Aspiration Syndrome (MAS), congenital diaphragmatic hernia, Respiratory Distress Syndrome (RDS), hyperviscosity syndrome, or neonatal pneumonia or sepsis. PPHN was formerly called persistent fetal circulation because the syndrome includes a reversion to fetal pathways for blood flow.  Management depends on the underlying cause of the persistent pulmonary hypertension:

• ECMO

• Exogenous surfactant

• HFV-group of assisted ventilation methods that deliver small volumes of gas at high frequencies and limit the development of high airway pressure, thus reducing barotrauma

Maintaining Body Temperature

• LBW infants have a limited capacity to increase their metabolic rate because of impaired gas exchange, caloric intake restrictions, or poor thermoregulation.

• Transepidermal water loss is greater because of skin immaturity in very preterm infants

• Rewarming should begin immediately by providing external heat. Important! Rapid changes in body temperature can cause apnea and acidosis.

Nutritional Care

Early enteral feeding of the asphyxiated neonate with a low Apgar score also is avoided to prevent bowel necrosis. In such cases, nutrition is provided parenterally. Infants who require parenteral nutrition are likely to have one or more of the following problems:

• Extreme prematurity where feedings must be introduced slowly

• Respiratory distress requiring aggressive ventilator support

• Asphyxiation with a potential for NEC

Type of Nourishment

The type, mode, volume, and schedule of feedings are based on:

• Initially, the birth weight, and then the current weight of the preterm infant

• Pattern of weight gain or loss (infants weighing less than 1500 g [3.3 lb] require more energy for growth and thermoregulation and can gain weight poorly with either breast- or bottle feedings)

• Presence or absence of suck-and-swallow reflex in all infants at less than 35 weeks of gestation

• Behavioral readiness to take oral feedings

• Physical condition, including presence or absence of bowel sounds, abdominal distention, or bloody stools, as well as presence and degree of respiratory distress or apneic episodes

• Residual from previous feeding, if being gavage fed

• Malformations (especially GI defects such as gastroschisis, omphalocele, or esophageal atresia), including the need for a gastrostomy feeding tube

• Renal function, including urinary output and laboratory values (nitrogen balance, electrolyte balance, glucose level); preterm infants are especially susceptible to altered renal function

Human Milk

Human milk is the best source of nutrition for term and preterm infants.

Weight and Fluid Balance

Caloric, nutrient, and fluid requirements of high-risk infants are greater than those of the healthy term newborn. The depletion of weight and metabolic stores can occur as a result of one or a combination of the

• Birth asphyxia

• Increased respirations or respiratory effort

• Patent ductus arteriosus

• Hypothermia or hyperthermia

• Insensible fluid loss caused by evaporation (with radiant heat or phototherapy)

• Vomiting, diarrhea, and dysfunctional absorption from the GI tract

• Growth demands (a preterm infant’s growth rate approximates that of fetal growth during the last trimester and is at least two times faster than a term infant’s growth rate after birth)

• nability of the renal system to concentrate urine and maintain an adequate rate of urea excretion, as well as infant’s inadequate response to antidiuretic hormone

• Insensible water loss (IWL): An evaporative loss that occurs largely through the skin (70%) and through the respiratory tract.

Advancing Infant Feedings

• Feedings are advanced as assessment data and the infant’s ability to tolerate the feedings warrant.

• Feedings are advanced slowly and cautiously.

• If advanced too rapidly, the infant can develop vomiting.

• If the infant needs additional calories, a commercial human milk fortifier can be added to the breast milk.

• Number of calories per 30 ml of commercial formula can be increased.

Nonnutritive Sucking

If the infant is receiving only TPN or gavage feeds, nonnutritive sucking should be encouraged:

• Improve oxygenation

• Lead to decreased energy expenditure with less restlessness

• Promotes positive weight gain and better sucking skills

The preterm infant is at an increased risk for infection because they have:

• A shortage of stored maternal immunoglobulins

• An impaired ability to make antibodies

• A compromised integumentary system (thin skin and fragile capillaries)

Preterm Infants: Signs and Symptoms of Infection

1. Temperature instability: Hypothermia, hyperthermia

2. Central nervous system changes: Lethargy, irritability

3. Changes in colo: Cyanosis, pallor, jaundice

4. Cardiovascular instability: Poor perfusion, hypotension, bradycardia/tachycardia

5. Respiratory distress: Tachypnea, apnea, retractions, nasal flaring, grunting

6. Gastrointestinal problems: Feeding intolerance, vomiting, diarrhea, glucose instability

7. Metabolic acidosis

Photo By: This file was contributed to Wikimedia Commons by National Archives at College Park - Still Pictures as part of a cooperation project. The donation was facilitated by the Digital Public Library of America, via its partner Digital Public Library of America.Record in source catalogDPLA identifier: 780954c6430e45444b05a0915ae6f20dNational Archives Identifier: 6361894, Public Domain, https://commons.wikimedia.org/w/index.php?curid=96695405 

Elimination Complications:  Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is an acute inflammatory disease of the GI mucosa, commonly complicated by bowel necrosis and perforation. The etiology and pathophysiology of NEC are unclear. Many factors seem to contribute to development.  The are three primary conditions:

1. Intestinal ischemia that occurs as a result of asphyxia/hypoxia or events that cause a redistribution of blood flow away from the GI

2. Bacterial colonization of the initially sterile GI tract with harmful organisms prior to the establishment of normal intestinal flora

3. Enteral feeding

Breast milk seems to have a protective effect against the development of NEC.  The signs of NEC are nonspecific and may include:

• Decreased activity

• Hypotonia

• Pallor

• Recurrent apnea

• Bradycardia

• Decreased oxygen saturation

• Respiratory distress

• Metabolic acidosis

• Oliguria

• Hypotension

• Decreased perfusion

• Temperature instability

• Cyanosis

• Abdominal distention

• Increasing or bile-stained residual gastric aspirates

• Grossly bloody stools

• Abdominal tenderness

• Erythema of the abdominal wall

Management strategies are based on the degree of bowel involvement and the severity of the disease. The goal of treatment is to prevent progression of the NEC, intestinal perforation, and shock. Options include:

• Oral or tube feedings are discontinued

• Orogastric tube

• Antibiotic therapy

• Surgical resection is performed if perforation or clinical deterioration occurs

Neonatal Responses to Pain

There is clear evidence that neonates can feel pain, despite previous thinking that the immaturity of the nervous system prevented or blunted pain sensation and that neonates were incapable of remembering painful experiences. Pain in the neonate and pain in later life can be qualitatively different, but research has substantiated that newborns do experience pain. The pain response can:

• Decrease tidal volume

• Increase demands on the cardiovascular system

• Increase metabolism

• Cause neuroendocrine imbalances

The pain response is influenced by a variety of factors, such as:

• Characteristics of the painful stimulus

• Gestational age

• Biologic factors

• Behavioral state

Assessment of Neonatal Pain

In assessing pain, the nurse needs to consider:

• Health of the neonate

• Type and duration of the painful stimulus

• Environmental factors

• The infant’s state of alertness

The are several tools for infant pain assessment.  Included in this list are:

• CRIES:  assesses Crying, Oxygenation, Increased vital signs, facial Expression, and Sleeplessness

• Neonatal Infant Pain Scale (NIPS):  assesses facial expression, cry, breathing pattern, arm tone, leg tone, and  state of arousal

• COMFORT-B Scale: assesses alertness, calmness/ agitation, respiratory response (in mechanically ventilated children), crying (in spontaneously breathing children), physical movement, muscle tone, and facial tension

• Premature Infant Pain Profile (PIPP):  this is one of the most widely used scales for preterm infants because it considers behavioral, physiologic, and contextual indicators.

Healthy term newborns are exposed to fewer sources of pain than preterm infants in an NICU where the newborn may be subject to painful procedures.

Memory of Pain

The rewiring of the pain responses occurs in preterm infants who have been subjected to multiple painful treatments early in their lives. The nervous system networks of the preterm infant appear denser and have more branches than those in the average infant, leading to the conclusion that the pain threshold and sensitivity in once preterm infants is heightened for life.

Untreated Pain

The consequence of untreated pain in infants is that their pain is inadequately managed.

Management of Neonatal Pain

The goals of pain management are to:

1. Minimize the intensity, duration, and physiologic cost of the pain

2. Maximize the neonate’s ability to cope with and recover from the pain

Nonpharmacologic Management

Strategies include:

• Swaddling

• Containment and positioning

• Breastfeeding/breastmilk

• NNS

• Skin-to-skin care during the painful event

• Use of sucrose for procedural pain

• Distraction with visual, oral, auditory, or tactile stimulation can be helpful in term neonates or older

• Sensorial stimulation uses multiple senses to diminish minor pain

• Touch

• Massage

• Rocking

• Holding

• Environmental modification (e.g., low noise and lighting)

Pharmacologic Management

• Topical anesthesia is used for circumcision, lumbar puncture, venipuncture, and heel sticks

• Nonopioid analgesia (oral liquid acetaminophen) is effective for mild to moderate pain from inflammatory conditions

• Morphine and fentanyl are the most widely used opioid analgesics for pharmacologic management of moderate to severe neonatal pain.  This will usually be used for infants in the Neonatal Intensive Care Unit.