#32264: Newborn Assessment

Conducting a thorough neonatal assessment is necessary to ensure that the newborn transitions appropriately to extra-uterine life [1]. Skilled observation should begin at the time of birth and continue frequently during the first 24 hours. Nurses should be aware of the normal features of the transition period in order to detect disorders in adaptation soon after birth [2]. The newborn assessment provides much needed information concerning the state of health of the transitioning newborn as well as a basis with which to formulate further care.

Every infant presents uniquely and has certain individual needs. While the vast majority of infants transition without problems, some present with anatomical, physiologic, infectious, and developmental issues that should be addressed. The assessment of the newborn should begin with obtaining a health history and include the initial Apgar assessment, transitional assessment during the periods of reactivity, assessment of gestational age, and a physical examination. This systematic approach ensures a thorough exam.

Nurses in many different areas of nursing conduct newborn assessments. The information provided in this course includes warning signs, which require immediate attention, as well as basic, normal assessment findings in the newborn. Due to the large volume of information, this course primarily covers the first 24 hours of life.

A prenatal history is imperative to the comprehensive care of each newborn and should cover the maternal sequelae, family history, and fetal care history [3]. Maternal history consists of information concerning past pregnancies, including complications, and specifics of labor and maternal illness, including infections and the use of alcohol or drugs [3]. It should also elicit information regarding the current pregnancy, such as the quality and quantity of prenatal care, current laboratory values (including blood type and Rh factor and the results of standard group B streptococcus screening), and the presence of any significant risk factors to the fetus. Obtaining a family history involves inquiring regarding past illnesses, genetic issues, and physiologic problems of parents and siblings [3]. The neonatal history encompasses factors such as vital signs, Apgar scores, required stabilization interventions, and the newborn's general appearance and reaction to the environment [3].

RISK FACTORS

An understanding of the maternal/fetal risk factors is important for the anticipation of possible problems that the infant may experience. Risk factors may be divided into two categories: those that can be modified, such as smoking and drug use, and those that are inherent, such as diabetes and pre-eclampsia.

Smoking

The U.S. Preventive Services Task Force (USPSTF) recommends that clinicians ask all pregnant persons about tobacco use, advise them to stop using tobacco, and provide behavioral interventions for cessation to pregnant persons who use tobacco.

(https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/tobacco-use-in-adults-and-pregnant-women-counseling-and-interventions Last Accessed: August 4, 2023)

Strength of Recommendation: A (The USPSTF recommends the service. There is high certainty that the net benefit is substantial.)

Smoking during pregnancy continues to be an alarmingly common problem. It has been associated with an increased incidence of ectopic pregnancy, preterm birth, low birth weight infants, placental abruption, premature rupture of membranes, and sudden infant death syndrome (SIDS) [4,5,6]. Studies have shown that low birth weight can be attributed to maternal smoking in 20% to 30% of cases [1]. Smoking causes vasoconstriction, resulting in decreased uterine perfusion and decreased oxygen-carrying capacity for the fetus [4,7]. Smoking has also been implicated in poor fetal nutrition, as it interferes with the ability of the fetus to metabolize key vitamins and minerals [4]. Cigarettes contain nicotine, which is a highly addictive substance. Infants of smokers tend to be fussier than those of nonsmokers, and it is thought that they experience nicotine withdrawal symptoms, especially if they are bottle-fed [6].

Drug Use

Illicit drug use can lead to a multitude of problems for the developing fetus. Cocaine, for example, affects all of the user's body systems, including the cardiovascular system, which can lead to heart attack and stroke. It may cause liver disease and perforation of the nasal septum [4]. It is highly addictive. The effect of cocaine on the fetus is directly related to the effect on the mother, including increased blood pressure, which leads to decreased uterine blood flow and perfusion [1]. These effects may lead to preterm labor, low birth weight and length infants, a decreased head circumference, placental abruption, and stillbirth. Additional effects of prenatal cocaine exposure include cerebral infarcts, renal defects, necrotizing enterocolitis (NEC), cardiac anomalies, and mild facial dysmorphic features [1].

Opioid use during pregnancy can be equally devastating. Maternal signs of opioid use include constricted pupils, slurred speech, euphoria, and respiratory depression [4]. Possible effects on the fetus include meconium aspiration, spontaneous abortion, and low birth weight, which may lead to future developmental problems [8,9]. Infants who are born physically dependent on opioids experience intense acute and subacute withdrawal symptoms [8,9,10].

Studies regarding the effect of cannabis use during pregnancy have shown inconsistent results [2,11]. It is thought that smoking cannabis has similar dangers as smoking cigarettes, including increased carbon monoxide levels, which lead to decreased oxygen levels and fetal hypoxia. Some studies have shown that women who smoke cannabis regularly during pregnancy are more likely to give birth to an infant with fetal alcohol syndrome-like characteristics [2]. Other studies have shown that prenatal exposure to cannabis is directly associated with lower birth weight, reduced birth length, and a smaller head circumference [11,186]. Cannabis readily crosses into breast milk, and women that smoke cannabis should be advised against breastfeeding [2].

Diabetes

Gestational diabetes affects up to 9.2% of all pregnancies [12,13]. Factors that place women at higher risk for developing gestational diabetes include age of 25 years or older, obesity, and a family history of type 2 diabetes [4,14]. The infant of a mother with diabetes, regardless of whether the cause is gestational diabetes or pre-existing disease, is affected in a multitude of ways. The effects are more pronounced in "brittle" cases. Fetuses that are continuously exposed to high blood glucose levels will produce more insulin in response, leading to excessive fetal growth and infants who are large for gestational age (i.e., macrosomia) [1,14]. This in turn can place them at higher risk for birth trauma and shoulder dystocia [4]. In the neonatal period, infants of mothers with diabetes are also more likely to experience hypoglycemia that results from the precipitous drop in available blood sugar while they continue to produce excessive amounts of insulin. This can lead to serious neurologic damage with complications including developmental delay, heart failure, and seizures [13,14,15]. Infants of mothers with diabetes are also at higher risk for neonatal jaundice, and women with diabetes are at higher risk for developing pre-eclampsia [4,14]. These infants are also more likely to be obese and develop type 2 diabetes as adults [13].

Pre-eclampsia

Pre-eclampsia is a form of pregnancy-induced hypertension that begins after 20 weeks' gestation. The diagnosis is based on the presence of new-onset hypertension (after 20 weeks' gestation) and at least one of the following: proteinuria; thrombocytopenia; kidney or liver function changes; pulmonary edema; or new-onset, severe, unrelenting headache. Accompanying signs may include headache, visual disturbances, and epigastric pain. Management of pre-eclampsia includes blood pressure control, bed rest, and fluid restriction. The only cure is delivery. The fetus is affected as a result of the hypertension leading to decreased uterine perfusion; chronic hypoxia can result. Infants of women with pre-eclampsia are at higher risk for low birth weight and the catastrophic event of placental abruption [4,16]. Untreated pre-eclampsia may result in eclampsia, which includes the development of seizures. The infant of a woman with eclampsia is at risk for effects of placental abruption, preterm birth, and acute hypoxia [4,16].

Group B Streptococcus

Group B streptococcus (GBS) is a leading cause of early-onset neonatal sepsis causing death to newborns [17,18]. Group B streptococcus is found in the mother's genital tract and rectal area [19]. Colonization is common and generally causes no symptoms in the healthy mother. In its 2010 guidelines, the Centers for Disease Control and Prevention (CDC) recommended universal rectovaginal screening of all pregnant women between 35 to 37 weeks' gestation, with subsequent intrapartum antibiotic prophylaxis; however, in 2019, the American Society for Microbiology (ASM) assumed responsibility for maintaining and updating these guidelines [17,18,143]. The ASM currently recommends screening between 36 weeks to 37 weeks/6days [143]. Universal screening has helped decrease the incidence of early-onset neonatal GBS; however, the incidence of late-onset neonatal GBS has not decreased [17,18,143]. Infants generally become infected during labor and birth due to vertical transmission of the bacteria after the membranes have ruptured; therefore, sepsis is a more likely outcome with delayed delivery after rupture of the membranes. Occasionally, fetuses may become infected during pregnancy.

As noted, there are two different types of GBS infection: early- and late-onset. Early-onset GBS occurs in the first seven days of life and may be detectable in the first six hours [19,20]. It can make a seemingly healthy newborn become ill very quickly. The most common symptoms of early-onset GBS are pneumonia, meningitis, respiratory distress, and sepsis [19,21]. Early-onset GBS has a higher fatality rate than late-onset GBS. Late-onset GBS may not be detected for up to three months and is believed to be transmitted either during birth, through breast milk, or in a nosocomial form [19,21,22]. The most common symptoms are sepsis and meningitis.

GBS sepsis should be considered whenever a newborn demonstrates respiratory distress, temperature instability, or poor feeding. Laboratory values that may be assessed when there is suspicion of GBS include complete blood count with differential, blood culture, chest x-ray, urine culture and analysis, stool culture, and possible lumbar puncture [23]. Treatment of GBS-infected newborns includes IV antibiotics [24].

A thorough assessment of the placenta at the time of delivery may assist with age determination and present significant diagnostic information [3]. The placenta should be assessed for size, color, odor, and the presence and number of membranes [3,25].

The ratio of fresh placental weight to infant weight is normally 1:6 in the last trimester. Very large placentas may be indicative of diabetes; very small placentas may be indicative of chronic hypoxia, perhaps caused by hypertension. The placenta should have a uniform thickness throughout; depressions may be from abruption or infarction [3,25,26].

Color may give an estimate of gestational age, as the placenta will become duller with more calcium deposits postdate. Pallor or plethora should be noted as they may indicate fetal blood volume inadequacy or excess and/or hemoglobin status. Staining by meconium or blood through the membranes or of the cord indicates an insult of longer duration. Vernix nodules (or amnion nodosum) indicate prolonged extreme oligohydramnios and pulmonary hypoplasia. An adherent clot suggests that an abruption has occurred. Any of these abnormal findings should be noted [3,25,26].

The placenta should be essentially odorless except for the slight odor of fresh blood. Foul odor indicates infection. This should be noted, and the physician should be informed [3,25,26].

Membranes should be assessed and noted to be present (i.e., not retained inside the uterus). The number of membranes should be determined in the case of multiple gestations [3,25,26].

The umbilical cord should be assessed for appearance, length, and diameter. The appearance of the insertion site should be documented, noting intactness, the number of vessels, and color. The umbilical cord should be a pearl ivory color, and any deviations from this color should be noted. The umbilical cord length is normally between 55 and 60 cm, with 5% of cords shorter than 35 cm and 5% longer than 80 cm [25,26,27]. Shorter length may be the cause of decreased fetal movement, intrauterine constraint, placental abruption, or cord rupture [27]. A longer cord makes entanglement or prolapse more likely. The cord diameter at term is generally about 1.5 cm and should be relatively uniform throughout, without strictures. The Wharton's jelly should be firm, with compression a likely result if the cord is thin [3,26,27].

Approximately 85% to 90% of infants make the transition from intrauterine to extrauterine life with no assistance necessary [28,29]. However, for the remaining few newborns, some assistance may be required, ranging from simple stimulation to complete resuscitation.

All nurses should be familiar with the ABCs of resuscitation: airway, breathing, and circulation. Because newborns are wet when they are born, they can suffer rapid heat loss if a warm environment is not maintained [28]. Therefore, it is critical to maintain a warm, or thermoneutral, environment for the infant throughout the first hours and days of life. This can be accomplished by placing the infant on the mother's abdomen, with warm blankets placed over them both to maintain body heat. Alternatively, if the need for further intervention is anticipated, or if the caregiver prefers, the infant should be placed on a preheated radiant warmer.

As the infant is being dried with warm blankets, the nurse should also be evaluating the infant's airway, breathing, muscle tone, color, and gestational age. All of these things should be evaluated within the first 30 seconds of life. The airway should be cleared with a bulb syringe or mechanical suction, and the infant should be positioned in such a manner as to facilitate an obstruction-free airway. If, in the initial evaluation, the infant is found to be clear of meconium, is breathing or crying, has good tone, is pink, and appears to be term gestation, then routine care need only be provided [28]. Routine care is comprised of assuring that the infant is warm and dry and keeping the airway clear. According to Neonatal Resuscitation Program standards, further care is warranted if the newborn fails to respond to birth in this positive manner [28].

In the United States, antibiotic eye ointment for the prophylaxis of ophthalmia neonatorum is highly recommended in all newborns [30,31,32]. Ophthalmia neonatorum is the inflammation of the eyes resulting from exposure to gonorrhea or chlamydia as the infant passes through the birth canal and can lead to blindness [30]. Administration of vitamin K intramuscularly is also common in the United States to prevent hemorrhagic disorders [4]. Coagulation alteration is seen predominately in infants in the second or third day of life, specifically because factors VII, VIII, IX, and X are dependent on the synthesis of vitamin K [33,34].

In 1953, an anesthesiologist named Virginia Apgar designed a tool for evaluating newborn infants [35]. The Apgar scores grade the infant's response to extrauterine life in five categories [36]:

There are a maximum of 2 points possible in each category, for a total of 10 possible points. The Apgar determination is completed at one and five minutes of life. It is important to note that resuscitative measures should not be delayed while awaiting the one- and five-minute marks for Apgar determination.

Morbidity and mortality findings have been found to correlate with the five-minute Apgar score [37,38]. The one-minute Apgar score correlates with the pH of cord blood. The lower the score, the more acidotic the infant; in addition, infants with lower scores have worsening cardiorespiratory depression [35]. Some studies have suggested that the Apgar score loses clinical significance for infants of 23 to 25 weeks' gestation who survive their first 24 hours of life [39].

Heart rate can be determined either through auscultation of the apical pulsation or by palpating the umbilical cord. A heart rate greater than 100 beats per minute (bpm) is awarded a score of 2 points. A pulse of less than 100 bpm garners 1 point. An absent heartbeat would obtain zero points [35,36].

Assessment of the respiratory effort requires a multifaceted approach. Movement of air in and out of the lungs may be auscultated at the time that a respiratory rate is obtained. An infant with a good cry is awarded 2 points for respiratory effort. An infant that is making some attempt at breathing but may be categorized as slow or irregular will obtain only 1 point. An irregular breathing pattern, also known as periodic breathing, is a normal finding in some newborns. However, if periodic breathing is associated with nasal flaring, grunting, retractions, cyanosis, or decreased rate, further assessment and intervention may be required. A newborn with an absent respiratory drive will receive zero points [35,36].

The nurse considers muscle tone acceptable if the infant's elbows, hips, and knees are flexed and allow active extension of extremities. The infant should return to the gently flexed position after examination. An attitude of flexion is necessary to obtain 2 points. An infant with some flexion should be assigned 1 point. A limp infant would receive zero points [35,36].

Reflex irritability is noted as the infant reacts to noxious stimulation. An appropriate response to stimuli, such as suctioning or rubbing the soles of the feet, would be for the infant to cry. This response would be awarded 2 points. If the newborn grimaces in response to such stimuli, 1 point would be awarded for effort. If the infant shows no response, then zero points would be awarded [35,36].

Color can be assessed by noting the color of mucous membranes, the trunk, and the soles of the feet. The infant should be pink and not dusky. An infant who is completely pink, including the hands and feet, would be awarded 2 points in this category. An infant that is pink but is acrocyanotic (i.e., has blue hands and/or feet) would receive 1 point. An infant that is blue, gray, or dusky would receive zero points [35,36].

Newborn screening programs began in the early 1960s with the development of a screening test for phenylketonuria (PKU) [40]. Newborn screening in the United States is a public health program aimed at the early identification of a variety of serious conditions, including genetic disorders (e.g., cystic fibrosis, hearing loss) and endocrine disorders (e.g., congenital adrenal hyperplasia, primary congenital hypothyroidism) [40,41]. In 2003, all but four states were screening for only six of these disorders. By 2022, most states reported screening for at least 31 (of 35 recommended) genetic and endocrine disorders on the standardized uniform panel of core conditions [41,44].

The adoption of a uniform newborn screening panel has led to earlier lifesaving treatment and intervention for newborns with these disorders [42,43]. The number and types of disorders screened for vary by state, but generally are guided by the Recommended Universal Screening Panel, which was developed by the U.S. Department of Health and Human Services [40,44].

All healthy newborns go through predictable periods of alertness and sleep that should be assessed and taken into consideration when performing the comprehensive physical examination. Distressed infants also progress through these stages but at a much slower rate [1]. These stages are called the first and second periods of reactivity.

The first period of reactivity generally lasts six to eight hours. For the first 30 minutes after birth, the newborn is generally very alert and active. The infant will usually have a vigorous suck reflex during this time, and it is generally an excellent time to begin breastfeeding. The infant will have open eyes and will be interested in looking around. Physiologically, the infant's respiratory rate may be increased and the lungs will sound quite wet. The heart rate may be increased, bowel sounds are active, mucus production is increased, and body temperature may be slightly decreased [1,45].

After this initial period of alertness, the newborn will go into a deep sleep that generally lasts from two to four hours, though it may continue much longer. During this period, the infant is very calm. Attempts to stimulate the infant will generally be unsuccessful. Ideally, the physical examination should be completed before this time and the infant can then be left alone to sleep. Physiologically, the infant will experience a decrease in respiratory rate, mucus production, and temperature and will likely not void or stool [1,45].

The second period of reactivity, which usually lasts two to five hours, begins when the newborn wakes from this deep sleep state. The infant is generally very alert once again and showing signs of hunger. This is an excellent opportunity for the infant and family to interact with each other and for the nurse to begin some teaching regarding hunger cues and other ways that the infant may communicate needs. Physiologically, the newborn's heart and respiratory rates increase, the gag reflex is active, and the production of mucus and meconium resumes [1,45].

Throughout the initial postbirth care and physical exam of the newborn, the nurse should be alert for signs of attachment forming between the infant and the parents. It is important for the nurse to look for those behaviors that lead to the successful process of attachment and bonding between parent and infant [1].

Unlike the physical examination, which uses concrete guidelines, the assessment of attachment requires the nurse to observe interactions and speak with the new parents regarding their expectations, dreams, and desires for their infant. This part of the newborn assessment can be challenging in today's hospital environment of shorter stays, but it is imperative in ensuring the well-being of the infant.

The following guidelines may be used when assessing infant-parent attachment [1]:

After the prenatal history has been obtained, the placenta has been evaluated, immediate postbirth care has been provided, and Apgar scores assigned, one can proceed with the physical examination. As with other facets of nursing care, the physical assessment always begins with the general appearance.

One important assessment strategy is to discuss the upcoming assessment with the infant's parents. Including the parents during the assessment allows the healthcare provider to point out both normal and abnormal findings. Optimizing this time with the parents assists them in understanding their infant and allows them to ask questions [46].

The following findings are considered warning signs that may be seen during the general assessment [35]:

Should these findings be noted, they would warrant immediate further investigation and treatment.

As noted, maintaining a thermoneutral environment is an important consideration. The assessment of any newborn should be conducted in a warm, well-lit environment. Cooler environments stress the newborn and may lead to inaccuracies in assessment. For example, incorrect findings may be made if the patient is found to look blue, experience bradycardia, or have cold hands and feet due to a hypothermic environment.

The assessment of the infant can be conducted through inspection, auscultation, and palpation. Inspection should occur before physical contact is made with the infant, though the need may arise to remove blankets, diapers, or clothing in order to complete a thorough inspection. Whenever possible, complete the observation portion of the assessment before touching the newborn. Observe the infant's position, temperament, sleep or wake cycle, color, movement, and respiratory pattern before disturbing the infant. Once the newborn has been disturbed, he or she may become agitated, resulting in a guarded posture, increased respiratory rate, and temperament changes. During the assessment, an inspection of the infant's activity level, color, respiratory effort, ease of movement, and posture should be noted [3]. During inspection, one should also note the appearance of any dysmorphic features. The finding of three or more dysmorphic features may warrant chromosome analysis [29,47].

During inspection, the activity level should be noted for sleep states progressing to irritability during the more intrusive parts of the exam [48]. There are six identified sleep states: deep sleep; active sleep; drowsy, in-between state; awake alert; alert and fussy; and crying [33,48,49]. The infant should be assessed in an awake alert state, which has been identified as the infant being bright, focused, and minimally active [29,33,48,49]. Motor activity, such as tremulousness, irritability, and defensiveness, should be noted both before and during the assessment [48].

Proper lighting is important as the accurate assessment of a newborn's skin can be useful in determining problems. Even if a newborn is slightly icteric at birth, making this determination can be useful in following the infant for potential problems related to jaundice. If the lighting of the examination room is inadequate, the slight appearance of jaundice may be overlooked. Color is important in determining pulmonary and cardiac involvement and thermoregulation, as well as other organ function in the newborn. Changes in the infant's color may occur throughout the exam when the infant cries, becomes cool, or is irritable. Assessment should be made for jaundice, cyanosis, pallor, and plethora [3]. It is important to note that acrocyanosis, the blue or dusky hands and feet with a pink trunk and mucous membranes, is frequently found and does not indicate a major problem.

Respiratory effort should be assessed by noting the rate and quality of breaths. Depth of breathing, retracting, grunting, nasal flaring, head bobbing, and posture changes associated with inadequate effort should be noted. Periodic breathing by the newborn (i.e., taking several breaths in a row then pausing for up to 15 seconds) is a normal finding. However, grunting, flaring, retractions, and head bobbing warrant further investigation [29]. A full discussion of respiratory assessment follows later in this course.

During inspection, resting posture offers many clues to the health of a newborn. In a healthy, full-term newborn, the posture should be that of flexion [1,29]. Muscle tone, including the amount of flexion or extension, should be assessed. Asymmetry of extremities, comparison of upper and lower extremities, and flaccid posture or contraction should be noted and further evaluated during the exam. The newborn's ease of movement should be noted throughout the assessment. The levels of fluidity and spasticity should be observed.

General measurements should be performed on each newborn. Infants who are found to have values outside the accepted range may require further evaluation and treatment. Weight, length, head circumference, and chest circumference measurements allow the practitioner to find abnormalities. Plotting these abnormalities provides a quick reference for comparisons with acceptable ranges.

Protocols vary regarding which infants require gestational age assessment. Some clinicians feel that this assessment should be standard for all newborns, while others use this tool on a case-by-case basis. A gestational age assessment should be performed on any infant that is thought to be premature or when there is a question of gestation. When assessing the gestational age of newborns, the New Ballard Score is often used [3,61]. The New Ballard Score takes into account both neuromuscular and physical maturity [45]. The score sheet includes scales that have grades of -1 through 5. Once the assessment is complete and the scores assigned, the scores are simply added. The total score is then correlated with the corresponding number of weeks to give the clinical determinant of the newborn's age.

Gestational age should be assessed within the first four hours of birth for maximum reliability [33]. The nurse should initially conduct the parts of the examination that can be done without disturbing the infant. This includes the physical maturity section of the New Ballard Score as well as the resting posture component of the neuromuscular maturity section.

CASE STUDY

The following discussion appears in the order in which the examination should be conducted. Please follow along with the New Ballard Score (Figure 1).

NEW BALLARD SCORE

Figure 1

Source: [Reprinted from The Journal of Pediatrics, 119(3), J.L. Ballard, J.C. Khoury, K. Wedif, C. Jarg, B.L. Walsman, and R. Lipp, “New Ballard Score Expanded to Include Extremely Premature Infants.”] Copyright 1991 by Mosby, Inc., with permission from Elsevier.

Resting posture should be evaluated first before the infant is disturbed. The infant should be supine on a flat surface [33]. There are five choices, ranging from 0 points, for a flaccid infant, to 4 points, for a completely flexed infant. Infant A is lying quietly on her back with her arms out to her sides at a greater than 90-degree angle. Her legs are bent at the knee with only a small amount of flexion. She should be awarded 2 points for posture.

The skin should be evaluated next. There are seven subclassifications in the skin category. The extremely premature infant has transparent, friable skin and woulsd be awarded -1 points. The postmature infant presents with leathery, tough, cracked skin and would receive 5 points. Infant A has a fine rash. There appears to be some peeling, with few veins visible on the abdomen. She is awarded 2 points for her skin maturity.

The presence or absence of lanugo (i.e., fine body hair) is evaluated next, with six categories from which to choose. The extremely premature infant is bald, not having had the opportunity to develop lanugo. The postmature infant is also mostly bald because the majority of lanugo has fallen out prior to birth. Infant A has large bald patches but still has a significant amount of hair on her back and ears. She receives 3 points.

Next, the soles of Infant A's feet are examined. Creases begin forming at the top of the newborn's foot and progress to the sole with maturity [33]. There are seven categories from which to choose in this area of assessment, ranging from -2 to 4 points. The extremely premature infant has a smooth sole and should be given points based on the size of the foot. The postmature infant has creases over the entire foot, which often appears cracked and leathery. Infant A has creases over the majority of her foot but not the entire sole. She receives 3 points for her feet.

Observing the presence and size of the breast bud is the next indicator of physical maturity. There are six categories from which to choose in this area. The extremely premature infant will have imperceptible breast buds, while the postmature infant will have well-developed 5–10 mm breast buds and a full areola. Infant A has a noticeable areola and a small bud measuring 2 mm. She is given 2 points.

The development of the newborn's eyes and ears are important markers of gestational age. There are seven categories from which to choose in this area. The extremely premature infant will have fused eyelids; the scoring on these infants is dependent on how tightly or loosely the eyes are closed. The postmature infant will have thick cartilage in the ears and they will be stiff. Infant A has open eyes, and her ears are soft but they do recoil easily. She is awarded 2 points for her eyes and ears.

The last area in the physical maturity assessment is genitalia. There are six categories from which to choose in this area. The extremely premature male infant will have a flat and smooth scrotum; the testes will not have descended into the scrotum. The extremely premature female infant will have an extremely prominent clitoris and flat labia. The postmature male infant will have descended testes and pendulous scrotum with deep rugae. The postmature female will show a labia majora that completely covers her clitoris and labia minora. Infant A has a large labia majora and a small labia minora. Her clitoris is not visible. She is awarded 3 points.

Returning to the neuromuscular maturity section of the New Ballard Score, the square window is measured by bending the wrist and visualizing how far forward the infant's hand can go. The extremely premature infant will have little flexibility in the wrist and show a greater than 90-degree angle. The postmature infant will have great flexibility and the hand will be completely in contact with the forearm. Infant A demonstrates a 30-degree angle when assessing the square window sign. She receives 3 points.

Arm recoil has much to do with the infant's flexion. One performs this test by actively extending the infant's arm to a straight position and letting go in order to evaluate how far back to full flexion the arm returns. In the extremely premature infant, there will be no recoil, and in the postmature infant, there will be full recoil. Again, an observation of the angle determines the point assignment. Infant A recoils to a 140-degree angle. She is given 2 points.

Actively extending the infant's leg and placing the foot near the head may measure popliteal angle. The extremely premature infant will have great flexibility and will be able to demonstrate a completely straight leg in this posture. The postmature infant will show little flexibility and will be unable to extend the knee to greater than 90 degrees. Infant A extends her leg to a 100-degree angle and is given 3 points.

Scarf sign may be measured by extending the infant's arm across the body and measuring how far across the elbow falls. The extremely premature infant will demonstrate great flexibility, and the elbow will be able to stretch all the way across the body. The postmature infant will show little flexibility and will barely get the elbow to meet the inner chest wall. Infant A is able to get her elbow to midline and is awarded 2 points.

The last marker of neuromuscular maturity is the heel to ear sign. This sign is measured by actively extending the infant's foot and attempting to reach the ear. The extremely premature infant will be able to touch his or her foot to the ear, while the postmature infant will be unable to extend a foot anywhere near the ear. Infant A can only extend her foot to a right angle above her body and is given 3 points.

Finally, the points for each category are added to give an estimated gestational age. In our example, Infant A received 15 points in the neuromuscular maturity area and 15 points in the physical maturity section. This is a grand total of 30 points, making her approximately 36 weeks' gestation.

A thorough skin assessment can be an important tool that provides invaluable information. Skin can deliver insight into the newborn's thermoregulation system, tell the experienced practitioner about the newborn's cardiac and respiratory functioning, be an invaluable indicator of gestational age, and be the first indicator of an infectious process.

SKIN COLOR

Color is a valuable finding in the assessment of a newborn. Due to variations in newborns' skin tones, an assessment may vary between healthcare personnel. In this case, an agreement of what to call the color should be noted between personnel so that fluctuations from the baseline color may be quickly identified. If an infant has a normal cardiorespiratory function, the mucous membranes, nail beds, palms of hands, and soles of feet will be pink in lighter-pigmented infants [63]. In darker-pigmented infants, color may be light pink with a yellow or red tinge. It is important to keep in mind that acrocyanosis is a normal finding in the first 24 to 48 hours of life, and an infant can still be considered pink if his/her mucous membranes and trunk remain so, even if the extremities remain blue or pale [64]. Alterations in cardiovascular or respiratory function may present in the form of mottled or dusky skin color. Pallor can be a sign of poor perfusion or anemia. If the infant's skin appears to be pale, then it should be noted and reasons should be identified. Other symptoms of poor skin perfusion are mottling and delayed capillary refilling [63]. Central cyanosis, or a blue color of the face, trunk, or mucous membranes, is not a normal finding and should be acted upon immediately.

Hyperbilirubinemia

Neonatal hyperbilirubinemia, or jaundice, is the yellowish discoloration of an infant's skin and sclera caused by a buildup of the bile pigment bilirubin. Hyperbilirubinemia that is noted in the first 24 hours of life is considered pathologic and should be treated appropriately [65]. Hyperbilirubinemia is a normal variation to a certain degree, and most infants will show some signs during the first week of life [65]. The severity and diagnosis of hyperbilirubinemia is dependent on the bilirubin level at a certain newborn age as well as the presence of risk factors [65,66].

The Academy of Breastfeeding Medicine asserts that clinicians should identify lactation risk factors and assess the infant's weight, hydration, jaundice, feeding activity, and output.

(https://www.bfmed.org/assets/DOCUMENTS/PROTOCOLS/Protocol%20%2314%20-%20English%20Translation.pdf Last Accessed: August 4, 2023)

Level of Evidence: III (Opinions of respected authorities, based on clinical experience, descriptive studies and case reports; or reports of expert committees)

Newborns become jaundiced for two main reasons: immaturity of the liver and/or the excessive amount of fetal hemoglobin that is required in utero. The liver is thought to be one of the last organs to fully mature; therefore, even the full-term infant may be considered to have an immature liver. The liver is where bilirubin, a byproduct of hemoglobin metabolism, is processed, and the immature organ may not be able to keep up with the increased demand that occurs shortly after birth. The increased demand is caused by the breakdown of fetal hemoglobin.

In utero, fetuses are exposed to a much lower partial oxygen pressure (PO₂) than that of the air they begin to breathe as soon as they are born. For this reason, they are in need of a much higher amount of fetal hemoglobin than is necessary after they are born. Fetal hemoglobin has unique characteristics. It has less oxygen carrying capacity, though it does have a greater affinity for the oxygen molecule. Because of the strong oxygen affinity, the oxygen does not unload until the tissue oxygen levels in an infant are lower than they would be in an adult. After they are born, infants begin to rapidly break down the excess hemoglobin to adjust to the much higher PO₂ of the air. When fetal hemoglobin is broken down, the heme is converted to biliverdin and then to unconjugated bilirubin. When the unconjugated bilirubin level exceeds normal, there becomes an increased chance of it depositing in the basal ganglia. Deposition of unconjugated bilirubin in the brain is known as kernicterus, a chronic and permanent form of hyperbilirubinemia that can be life-threatening [66].

For newborns that present with jaundice, the American Academy of Pediatrics (AAP) has several recommendations. Total serum bilirubin or transcutaneous bilirubin levels should be measured within the first 24 hours of life, as observational assessment of the degree of jaundice severity is inaccurate and does not take into account the appearance of infants with darker skin pigmentation [66]. Bilirubin levels should be considered in relation to the age of the newborn (i.e., measured by hours) [66]. Infants younger than 38 weeks' gestation who are breastfed are at greater risk of developing hyperbilirubinemia; these infants require additional observation [66]. All infants should be screened for the risk of developing severe hyperbilirubinemia, and parents should be provided with written and verbal information about neonatal jaundice prior to hospital discharge [66].

Obtaining a thorough history for risk factors of hyperbilirubinemia is essential. The causes of jaundice may be related to Rh incompatibility, abnormal blood cell structures, birth injury, polycythemia, glucose-6-phosphate dehydrogenase or pyruvate kinase deficiency, infection, certain medications, and prematurity [65]. Depending on the cause of the hyperbilirubinemia, treatment includes more frequent feedings, phototherapy, maintaining active bowel routines, and, occasionally, exchange transfusions [65,66].

When assessing the newborn's head, one begins with the general appearance of the head, including the shape, circumference, suture lines, and fontanelle size [74]. Symmetry or asymmetry should be noted, though asymmetry can be a normal variation resulting from the fetal lie in utero. Facial bruising is commonly caused by birth trauma and should be noted. The following section addresses assessment of the newborn's head shape, size, and fontanelles.

According to the American Academy of Ophthalmology, neonatal conditions that prove to be the most severe and threatening to vision are congenital cataract, retinopathy of prematurity, congenital glaucoma, retinoblastoma, and cerebral visual impairment [82]. There are many risk factors for eye conditions in the newborn, including systemic conditions, neurologic disorders, perinatal complications, and a family history of eye or vision problems [82]. Special attention to eye health should be given to infants who are born prematurely and/or have multiple conditions [82,83].

Following an examination of the general size and appearance of the head, the nurse should assess the eyes. Warning signs should be noted followed by an orderly assessment of eye size, shape, placement, sclera color, and reflexes. Observations of any anomalies should be reported immediately [82].

All regions of the eye should be examined thoroughly for dysmorphic features. Determining the symmetry and completeness of brows and lashes with intact lid margins is important [47]. Initial observations should assess that the eyes are equal in size and placed symmetrically on the face. The outer corner of the eye should be at the same height as the top of the ear, if one were to draw an imaginary line between the two. Low-set ears may be associated with other signs of trisomy 18 or trisomy 21, such as Brushfield spots, a speckling of the iris [75]. Short palpebral fissures are associated with fetal alcohol and other syndromes [84].

When assessing for dysmorphic features, any missing or defective ocular tissue or incomplete development of portions of the eye should be noted as a possible coloboma. Colobomas may involve the eyelid margin or the iris and retina and are associated with several syndromes [85]. The iris may be absent altogether, referred to as aniridia; this most often occurs bilaterally [85].

The upper lid should cover only the top part of the eye. Drooping of the eyelid, or ptosis, may signal neuromuscular weakness [35]. "Doll's eyes" are characterized by a lag in eye movement [86]. This is a normal finding in newborns with muscular immaturity [87].

Epicanthal folds are vertical folds of skin covering the inner canthus of the eye. Epicanthal folds commonly occur among some races (i.e., Asian, Native American) and in newborns of any race prior to the elevation of the bridge of the nose [88]. However, presence of epicanthal folds has also been associated with fetal alcohol syndrome, Down syndrome, and Turner syndrome [88].

Examination of the internal parts of the eye should follow the peripheral examination. Lifting the infant's head while he or she is in the supine position encourages the infant to open its eyes [34]. Term infants are myopic, with a visual acuity of 20/200. Their optimal visual field is approximately 8–12 inches, or about as far away as their mother's face would be during feeding. The lids should unfuse by 28 weeks' gestation, but infants do not have full muscle control of the eyelids at birth. It is also important to assess newborns' tears and exudate. Exudate that is copious, greenish-yellow, or persists or appears after 24 hours of age is a sign of underlying infection [35,85].

The sclera may be white or bluish-white. A yellow appearance of the sclera is indicative of jaundice. Subconjunctival hemorrhage may be present from the pressure of birth. Any irregular shape or unequal size of the iris or pupil should be noted. A white pupil, or cat's eye reflex, indicates abnormalities [85,89]. Downward deviation of the irises exposing the sclera, or sun-setting sign, may be caused by hydrocephalus [90]. When assessing the infant's pupils the terms "equal," "round," "reactive," and "accommodating" can be helpful.

The red reflex is characterized by an equal and round red area of light at the pupil. If a red reflex is absent, white, dull, opaque, or asymmetric, the infant should be further examined for congenital cataracts, and dysmorphia related to chromosomal abnormalities should be considered [35,47,82,85].

There are several eye reflexes that should be examined. The blinking reflex can be tested either by bright light or a light touch. The infant should demonstrate an immediate blink when the eyes are stimulated. The corneal reflex is tested by a light pressure applied to the cornea with a piece of cotton, which should induce an instinctive blink. This reflex is not generally examined unless brain or eye damage is suspected [1]. The pupillary reflex may be determined by shining a light into the eye. The pupil should constrict instantly. Both eyes should be examined in the same manner, with a comparison made between the two. They should have equal size constriction in the same amount of time.

Examination of the ears should include size, shape, and location. Ear cartilage becomes firmer as the fetus ages, so preterm infants may have more pliable ears. The placement of the ear should be assessed as it relates to the inner canthus of the eye. A normal ear will at least touch the imaginary horizontal line. If the top of the ear falls below the line, then the ear is considered low set. A low-set ear may indicate chromosomal abnormalities (e.g., Down Syndrome, Turner Syndrome) and may be associated with renal complications [91,92]. The ears can be measured at their longest axis and compared to standardized charts for determination of dysmorphia [47]. Ears are considered small if less than 2.5 cm in the term infant [47].

The USPSTF recommends screening for hearing loss in all newborn infants.

(https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/speech-and-language-delay-and-disorders-in-children-age-5-and-younger-screening Last Accessed: August 4, 2023)

Strength of Recommendation: B (There is high certainty that the net benefit is moderate or there is moderate certainty that the net benefit is moderate to substantial.)

In addition to size and position, appearance should also be analyzed for malformations, including absent pinna, abnormal folds, discharge, reddening, or preauricular tags [93]. Abnormal structure may be indicative of other conditions [94,95].

The National Institutes of Health (NIH) and the Joint Committee on Infant Hearing recommend the implementation of universal newborn hearing screening. Since the NIH first endorsed screening all newborns for hearing loss, the number of infants identified as hearing-impaired has increased dramatically [96]. According to the Joint Committee on Infant Hearing, more than 95% of newborns are assessed for hearing loss in the United States. However, nearly one-third of newborns who do not pass initial screening do not have appropriate follow-up to either confirm hearing loss and/or initiate appropriate early intervention services [97]. Technologies used to screen for hearing impairment in this population are auditory brainstem response and otoacoustic emission [97,98].

Infants with normal hearing should have some response to sounds and voices. In newborns, risk factors for hearing loss include a family history of hearing loss, neonatal intensive care stay of greater than five days, aminoglycoside administration of greater than five days, assisted ventilation, ototoxic medications, hyperbilirubinemia, in utero infections, craniofacial malformations, congenital microcephaly, temporal bone abnormalities, and ear anomalies [97]. However, as many as one-half of infants born with hearing loss in the United States have no known risk factors [92].

The nose should be assessed for placement, shape, patency, and the presence of drainage. The nose should be midline on the face. Nares should be symmetrical in placement and size. The assessment for dysmorphic features, such as asymmetric nares or a notched or broad nasal tip, is necessary [47].

A small amount of clear or white discharge from the nose may be noted as a normal finding in the newborn [35,77]. However, copious or discolored nasal discharge may be a sign of congenital syphilis or respiratory problems [77]. Patency may be determined by closing the infant's mouth and assessing the quality of respiratory effort. Obstructing one nare at a time can be useful in determining choanal atresia, which is a blockage in the posterior nasal passage. One can assess the movement of air in and out of the nares by placing a finger under the nares to feel air movement. Obstructed nasal passages are an important finding as newborns are obligatory nose breathers and usually cannot breathe orally even when compromised.

When examining the mouth of a newborn, symmetry, completeness, size, and color are considerations. The mouth should be midline and symmetrical [77]. Asymmetrical movement may be caused by nerve injury from birth trauma and may include other parts of the face.

Inspect the mouth, lips, tongue, and gums for deformities. If the lighting is poor, a pen light may be used to thoroughly visualize the palate. Gentle assistance should be employed to open the mouth while a second team member completes the assessment. The intactness of the palate may be determined by both visual and tactile strategies. The palate should be palpated for intactness by inserting a gloved finger, soft side up, and feeling the roof of the mouth. Alterations in the shape of the palate may cause breathing or feeding problems. Epstein's pearls, small calcium deposits that form midline on the hard palate, may be present. They will reabsorb within approximately one week [77].

The infant's tongue may appear large for its mouth and shorter than either a child's or an adult's [34,77]. Dysmorphic findings concerning the mouth, tongue, and chin include a flattened or elongated philtrum, disproportionate tongue, small chin, short frenulum ("tongue tie"), and cleft palates and lips [47]. If the infant's mouth remains open and the tongue protrudes, this may be a sign of an existing condition, such as Down syndrome, and should be noted [92].

The color of mucous membranes and lips should be monitored. The colors may be described as dark, purple, dusky, pink, or pale. Using a referenced color gauge or having two nurses assess the infant's color can help with the accuracy. Mucous membranes should be pink and well-hydrated, and a small amount of saliva should be present [77]. If there is a large amount of saliva and the infant is "blowing bubbles," the mouth should be suctioned with a bulb syringe [77]. If this does not resolve the issue, further assessment should be conducted to determine the patency of the esophagus before the infant is allowed to eat.

Observe for natal teeth. While natal teeth occur in normal infants, they are more likely to occur with cleft palate [85]. If teeth are present, they should be noted and reported. Natal teeth are generally removed to prevent a choking hazard, especially if they are loose [77].

The neck of the normal newborn is noticeably shorter and more flexible than that of an adult or child. The normal newborn will exhibit creasing and skinfolds on the neck. Infants are generally not capable of supporting their heads at birth and will experience head lag when they are moved to a sitting position from a lying one [33]. Assess lymph nodes and monitor for webbing and any masses [33]. Webbing of the neck, generally noticed from the back of the neck, may be indicative of chromosomal abnormalities [77].

Palpation of each clavicle may help determine intactness. A fractured clavicle may present with an elevation of the bone, or a grating sensation may be felt when manipulated [33]. The newborn should be able to demonstrate free range of motion that is symmetrical.

The newborn neurologic assessment takes into consideration the immaturity of the neurologic system. As the infant grows and develops, a more certain presentation of the intactness of the neurologic system will surface. When assessing neurologic status, one should be alert for warning signs and then proceed by assessing the newborn's reflexes.

A visual inspection of the chest should be completed initially for size, shape, symmetry of movement, and presence of identifying features. The chest should be round and 1–2 cm smaller than the circumference of the infant's head [92]. Chest circumference is obtained by measuring around the infant's chest at the nipple line midway between inspiration and expiration. Measuring the distance between the nipples divided by the chest circumference determines a narrow versus broad chest. In a narrow chest, the internipple distance will be less than 25% of the chest circumference. In a broad chest, the difference will be more than 33% of the chest circumference [47].

Assessment of the infant's breasts should include size, shape, and nipple formation, placement, and number. Breast bud size is an important indicator of gestational age. Some infants are born with supernumerary nipples, usually located vertically, below the normal nipple [92]. These are very rarely associated with any adverse effects or conditions [92,112]. As discussed, they are often mistaken for nevi [67].

Gynecomastia is common in either gender and may be noted as late as the second or third day of life. It is caused by high levels of maternal estrogen that have passed through the placenta, and should resolve spontaneously [1]. Neonatal gynecomastia is often accompanied by galactorrhea, also called pseudomenses milk or "witch's milk" [113]. In infants with galactorrhea, the discharge is usually bilateral. Unilateral, bloody, serous, or purulent discharge should be noted as a sign of an underlying pathologic cause [113]. According to the American Academy of Family Physicians, galactorrhea should also be documented as [113]:

If no underlying disease exists, galactorrhea will resolve spontaneously.

Throughout pregnancy, the fetus receives its oxygen through the umbilical cord from maternal oxygen stores. Oxygenated blood flows from the mother through the uterine artery into the intervillous spaces of the placenta, where gas exchange occurs [33]. Fetal circulation begins with the umbilical vein picking up the oxygen stores from the intervillous spaces of the placenta and transporting them to the fetal heart. Most of the blood bypasses the fetal lungs as they do not have a respiratory gas exchange function [33]. When an infant is born, therefore, a sequence of events must occur in order for the infant to breathe.

In utero, the pulmonary circulation has elevated pressures and low flow states because of high pulmonary vascular resistance [114]. The newborn's pulmonary vascular pressure is partially related to a higher CO₂ from passive maternal oxygenation and is partially related to the pressure applied by amniotic fluid inside the lung [114]. Also, pulmonary vascular pressures are consistently higher than systemic resistance prior to birth [114]. The result is that only 5% to 10% of the entire cardiac output is used for perfusion of the fetal lung [114].

Pressure increases on the fetal chest as the infant is expelled from the uterus during a vaginal delivery. The amniotic fluid inside the lung compartment is pushed out through the airway. Once the infant's head and chest are delivered, the chest re-expands, causing an intake of air to fill the void where amniotic fluid once was [115]. The first few breaths taken by the infant are critical to changes in pressures and functioning of the newborn's pulmonary function. The most common cause of spontaneous pneumothorax in infants is the degree of transpulmonary pressure generated by the first few breaths [116].

The exact stimulant for breathing may not become evident because the newborn is exposed to so many new factors at once, including pain, acidosis, light stimulation, and sensory factors, among others [114,117]. Physical (mechanical) factors that stimulate breathing include the compression of the fetal chest as it moves through the birth canal, and the chest wall recoil, which occurs as the newborn's trunk emerges. Chemical factors, such as the decreases in oxygen concentration and lack of placental blood flow, cause the medulla to stimulate the respiratory center to begin functioning [117]. Once the lungs are open to airflow, the pressure within the capillaries decreases and an increase in the amount of blood to the pulmonary bed occurs [117]. The change in temperature from the intrauterine environment to the extrauterine environment (a decrease of more than 20°F) also works to produce active respiratory effort. An increase in the blood flow to the pulmonary bed occurs as a result of pulmonary vascular relaxation. The pulmonary vascular bed relaxes due to the increase in oxygen saturation that the newborn is able to obtain using his or her circulatory system [114,117].

Due to the difference in fetal hemoglobin and exposure to lower PO₂ levels, laboratory data obtained from the newborn are considerably different than that of an older child or adult. The normal hemoglobin level in the newborn is 17–18 g/dL [33,34]. The newborn is born with up to 90% of fetal hemoglobin. Hematocrit elevation is a normal finding [34].

Leukocytosis of the newborn, caused by increased neutrophil production in the first days of life, is related to the stress of birth [33]. This phenomenon self-corrects in about two weeks.

A thorough evaluation of the infant's respiratory system includes two components. Inspection of the newborn's breathing effort and chest movement begins the process, followed by auscultation of the infant's lung fields. The infant's lungs are positioned anteriorly from above the middle third of the clavicles to the sixth rib at the midclavicular line and to the eighth rib at the midaxillary line. A thorough posterior assessment is warranted as the infant's lower lobes are primarily located posteriorly to the eleventh rib at the vertebral line [50].

CAUSES OF RESPIRATORY DISTRESS

Respiratory Distress Syndrome

Respiratory distress syndrome (RDS) is caused by surfactant deficiency and structural immaturity of the infant's lungs [120]. RDS has also been referred to as hyaline membrane syndrome due to the formation of hyaline membranes concurrent with this condition; however, hyaline membranes have also been associated with other respiratory conditions [120]. RDS is the recommended term to distinguish the specific symptoms characteristic of this condition.

The incidence and acuteness of RDS is directly related to gestational age. It is most prevalent in newborns younger than 28 weeks' gestation and/or weighing less than 1,200 g [120]. RDS affects more white infants than infants of other races [121]. Risk factors include maternal diabetes, caesarean delivery devoid of labor, latter born of twins, and familiality [120].

RDS presents either at birth or within the first eight hours of life [120]. If symptoms occur after the first eight hours, then it is unlikely that RDS is the cause. The most common signs of RDS are [120]:

• Tachypnea

• Dyspnea

• Grunting with expiration

• Intercostal retractions with inspiration

• Nasal flaring

• Increasing cyanosis

Oxygen and surfactant therapy are used for support and treatment. Minimizing disturbances, handling the infant gently, and maintaining an ideal body temperature will help reduce the infant's oxygen needs. Infants with RDS need careful fluid management and should be carefully monitored for signs of infection [120].

Transient Tachypnea of the Newborn

Transient tachypnea of the newborn (TTN) is a relatively common condition in near-term infants. It is thought to be caused by residual fluid or debris in the lungs and is more common in infants delivered via cesarean section [33]. TTN occurs more frequently with infant sedation via maternal medication, prolonged labor, fetal macrosomia, and maternal asthma [122].

The condition generally presents as mild respiratory distress with marked tachypnea, in some cases with rates up to 100 to 140 breaths per minute [33]. Though a thorough workup should be done to rule out other causes of respiratory distress, TTN is generally benign and will resolve within 48 to 72 hours [75,122]. Oxygen support may be required in severe cases [33].

Neonatal Sepsis

The presenting sign of sepsis in many newborns is respiratory distress. Therefore, a thorough septic workup is in order in a newborn with signs of respiratory compromise.

Neonatal sepsis is categorized as early onset when it presents within the first seven days of life; most cases present within the first 24 hours [123]. The leading cause of early-onset neonatal sepsis is GBS, followed by Escherichia coli[124]. Events that increase the risk of neonatal sepsis include [122]:

• Maternal infection with GBS during pregnancy

• Premature delivery

• Membrane rupture lasting longer than 24 hours

• Chorioamnionitis

• Frequent vaginal examinations during labor

In addition to respiratory distress, signs of sepsis may include behavioral changes (e.g., lethargy, temperature instability, feeding difficulty), jaundice, and cardiac changes, such as tachycardia or bradycardia. The following manifestations may be observed in neonatal sepsis [1]:

General Signs

• Infant generally "not doing well"

• Poor temperature control (i.e., hypothermia, hyperthermia [rare])

Circulatory System

• Pallor, cyanosis, or mottling

• Cold, clammy skin

• Hypotension

• Edema

• Abnormal heartbeat (i.e., bradycardia, tachycardia)

Respiratory System

• Irregular respirations (i.e., apnea, tachypnea)

• Cyanosis

• Grunting

• Dyspnea

• Retractions

Central Nervous System

• Diminished activity (e.g., lethargy, hyporeflexia, coma)

• Increased activity (e.g., irritability, tremors, seizures)

• Bulging fontanelle

• Increased or decreased tone

• Abnormal eye movements

Gastrointestinal System

• Poor feeding

• Vomiting

• Diarrhea or decreased stooling

• Abdominal distension

• Hepatomegaly

• Hemocult (i.e., positive stools)

Hematopoietic System

• Jaundice

• Pallor

• Petechiae, ecchymosis

• Splenomegaly

Although some studies have shown that the use of certain antibiotics may lead to antibiotic resistance and possible damage to the intestine, kidneys, liver, or hearing, antimicrobial therapy is still commonly used to treat sepsis [125]. The American College of Obstetricians and Gynecologists recommends that if the mother is receiving intrapartum antibacterial prophylaxis (IAP) for suspected GBS or chorioamnionitis and the newborn exhibits signs of sepsis, empiric therapy should be administered along with a complete diagnostic evaluation [24,126]. If the infant does not exhibit signs of sepsis but maternal chorioamnionitis is present, empiric therapy and a limited evaluation (i.e., blood culture and complete blood count) are indicated. If the gestational age is less than 37 weeks or the duration of maternal IAP has been less than four hours, a limited evaluation and close observation for a minimum of 48 hours are recommended [24,126]. If neonatal sepsis is suspected, empiric therapy should be administered along with a complete diagnostic evaluation. If there are no signs of sepsis, maternal IAP duration exceeds four hours, and the infant is older than 37 weeks' gestation, no evaluation or therapy is required [24,126]. However, the infant should be closely observed for a minimum of 48 hours. Penicillin is considered the most effective treatment [24,126]. Extreme cases may require assisted ventilation. As sepsis can have an extremely fast onset and cause rapid deterioration, it is imperative that treatment begin immediately.

The American College of Obstetricians and Gynecologists recommends, regardless of planned mode of birth, all pregnant women undergo antepartum screening for group B streptococcus (GBS) at 36 0/7–37 6/7 weeks of gestation, unless intrapartum antibiotic prophylaxis for GBS is indicated because of GBS bacteriuria during the pregnancy or because of a history of a previous GBS-infected newborn.

(https://www.acog.org/-/media/project/acog/acogorg/clinical/files/committee-opinion/articles/2020/02/prevention-of-group-b-streptococcal-early-onset-disease-in-newborns.pdf Last Accessed: August 4, 2023)

Strength of Recommendation: Expert Opinion/Consensus Statement

Meconium Aspiration Syndrome

Meconium aspiration syndrome (MAS) is another cause of respiratory distress in newborns and occurs in approximately 5% of those born with meconium-stained amniotic fluid [127,128]. It is caused by the aspiration of meconium-stained amniotic fluid into the trachea. Meconium staining may be noted by assessing the infant's skin, nails, and umbilical cord and can affect the infant's Apgar score [35]. Presence of meconium may clue the practitioner to assess for tachypnea, hypoxia, and hyper- or hypoventilation [86]. The presence of rales, rhonchi, wheezing, wet sounds with possible retractions, and labored breathing are possible, depending upon the extent of aspiration. Risk factors for MAS include [128]:

• Fetal distress, long labor, or difficult delivery

• Maternal diabetes

• Maternal hypertension

• Low oxygen supply to the infant in utero

Meconium aspiration is associated with asphyxia, but routine intubation and intrapartum suctioning are no longer recommended, regardless of the infant's activity level [127]. Gently clearing the nose and mouth of meconium with a bulb syringe may be warranted. A neonatal advanced life support team should be notified and available to treat a newborn with meconium-stained amniotic fluid [127]. Other treatments for MAS include oxygen therapy, mechanical ventilation, fluid support, a warmer to control temperature, and antibiotics [128,129].

The fetal cardiovascular system is markedly different from that of the newborn. Because the fetus does not rely upon its lungs for oxygenation, very little blood flows through the pulmonary vasculature. Fetal circulation begins with oxygenated blood traveling to the fetus through the umbilical vein. Note the unusual circumstance of a vein carrying richly oxygenated blood. The blood enters the fetus at the site of the umbilicus and divides into two branches. One branch carries blood to the fetal liver, while the other, larger branch carries blood through the ductus venosus into the fetal vena cava [33]. The oxygen-rich blood then travels to the fetal heart through the right atrium. In an adult, the blood passes into the right ventricle for distribution into the pulmonary vasculature, which would then oxygenate the blood. Because the blood in the fetus is already oxygenated, the majority then passes through the foramen ovale to the left atrium. A small amount of blood does pass into the right ventricle, which pumps the blood into the pulmonary artery to oxygenate the lung tissue. However, the majority of this blood also passes through another duct, the ductus arteriosus, into the aorta for distribution to the body [33]. The deoxygenated blood then leaves the fetus via two umbilical arteries for nutrient and gas exchange in the intervillous spaces of the placenta.

Once the newborn is breathing and maternal blood flow from the umbilicus stops, changes in blood flow, pressures, and volume occur within the heart, causing structural changes. The foramen ovale, which is a naturally occurring atrial septal defect, closes, as does the ductus venosus, due to the changes in pressure and flow [37]. The increase in arterial oxygen tension causes the ductus arteriosus to begin to close at a later time, approximately 12 hours after birth. It is completely closed no later than 21 days after birth [37,130]. The size and shape of the heart changes over a period of time as the left ventricle assumes the primary pumping role.

After the newborn's structural cardiovascular changes occur and the infant is breathing, the pressures in the heart and the volume of blood during flow also shift because of the new route. When the lungs begin receiving a higher concentration of oxygen, the pulmonary vascular bed relaxes, allowing blood to flow through the lungs [130]. Blood through the ductus venosus is halted following the clamping of the umbilical cord. The ductus venosus usually completely closes seven days after birth, though there is no flow through it after the umbilical cord is clamped. When the cord is clamped, it separates the newborn from maternal blood flow, causing systemic vascular resistance to rise. This is due to the increase in pressure of the newborn's circulatory system as opposed to the low pressures in the placenta [130].

It takes time for the fetal right ventricular muscle to remodel itself into the lesser pump side and decrease work [114]. Though the left side of the heart is functioning as in an adult, the muscle mass may not achieve complete dominance over the right ventricle until the sixth month of life [114].

The cardiovascular assessment is composed of auscultation, electrocardiogram (ECG) analysis, blood pressure monitoring, pulse quality, and capillary refill time. However, in the healthy term infant, many practitioners will do little more than auscultation if there are no other signs of problems. Cardiac abnormalities generally present themselves quite obtrusively.

Assessing the infant's abdomen includes inspection, palpation, and auscultation. Inspection will include looking at the shape, contour, and movement of the abdomen as well as assessing the umbilical stump. Auscultation should be done for bowel sounds and bruits. Palpation for abdominal masses, as well as for major organs, is an important aspect of the abdominal exam, followed lastly by assessment of the infant's stool.

Assessing stool quantity and quality is an important part of the gastrointestinal assessment. Meconium should be passed within 24 hours [75]. If the infant has not passed meconium within the first 24 hours, a further assessment is warranted to rule out ileus or obstruction. By the second or third day, the infant should begin to have transitional stool, which is green or yellowish and may have a seedy appearance. Within several days to a week, breastfed infants' stools take on the appearance of mustard.

NECROTIZING ENTEROCOLITIS

According to the American Society for Parenteral and Enteral Nutrition, minimal enteral nutrition should be initiated within the first two days of life and advanced by 30 mL/kg/day in infants ≥1,000 g at high risk for necrotizing enterocolitis.

(https://onlinelibrary.wiley.com/doi/pdf/10.1177/0148607112449651 Last Accessed: August 4, 2023)

Strength of Recommendation: Weak

Necrotizing enterocolitis (NEC) occurs most often in very low birth weight and low birth weight infants. In term infants, NEC is associated with the use of concentrated formulas, blood transfusions, NEC outbreak in the healthcare facility, and early use of certain medicines, such as indomethacin and dexamethasone. Early gastrointestinal signs may be ambiguous. Signs of NEC include lethargy, difficulty feeding, bilious emesis, temperature instability, abdominal distention and rigidity, abdominal tenderness, fecal occult blood, and palpable loops in the stool. In the later stages of NEC, a discoloration of the abdominal wall, the labia, or the scrotum may be seen. Because NEC symptoms are similar to other conditions, such as neonatal sepsis, care should be taken to provide immediate and accurate intervention [160,161,162,163].

Observe for color, odor, frequency, and amount of void. Failure to void with in the first 24 hours is considered a warning sign and warrants further evaluation. The normal urine output for an infant is at least 1–2 cc/kg/hour. Output may be as high as 4 cc/kg/hour in the first few days of life [50]. Urine output should be made with a stream of urine under an adequate amount of pressure. Urine is normally straw colored, though variations in color do exist, ranging from clear to amber, and may or may not have sediment.

During the initial head-to-toe assessment of all infants, a thorough examination of genitalia should be completed. The infant's genitalia should be assessed initially for appropriate development and function. Unusual appearance of the genitalia is more often a structural abnormality and not ambiguous genitalia [171]. Accurate diagnosis is vital in order to avoid adverse consequences and undue stress for the family [172,176]. However, a true case of ambiguous genitalia, or disorder of sex development (DSD), may be disturbing to parents and carries lifelong therapeutic and psychosocial implications [172,173]. Immediate intervention is required in newborns with a DSD in order to evaluate adrenal and pituitary function, as certain underlying conditions, such as congenital adrenal hyperplasia, may be life-threatening [154,170,174]. DSDs have variable etiology, ranging from chromosomal abnormalities to maternal ingestion of androgenic steroids or other drugs [175,176].

An expeditious assessment and decision on gender assignment is necessary for improved patient outcome and to ease parental anxiety [154,172,173]. Gender assignment is generally influenced by a variety of aspects, including diagnosis, structure and appearance of the genitalia, surgical alternatives, possible requirement of lifelong therapeutic measures, fertility, and family and cultural views and beliefs [154,172]. Due to the psychosocial implications of DSDs, the AAP issued a policy statement that addresses these implications, including revision and standardization of nomenclature and care [172]. The AAP recommendations for the clinical care of infants with DSDs include [172]:

The final portion of the head-to-toe assessment of the newborn is examining the extremities and back. A thorough examination of the arms and legs begins with noting the presence of any warning signs. Attitude, or resting posture, is an important piece of the neonatal evaluation, as is the evaluation of reflexes. The infant should be observed closely for the presence of tremors, and neuromuscular maturity and symmetry should be noted.

A thorough neonatal assessment should be performed on all newborns in the first hours after birth to ensure an appropriate transition to extrauterine life. This assessment should be done systematically so early intervention may be initiated in the event that an abnormality is discovered. The prenatal record should be reviewed whenever possible to be aware of newborn and/or maternal risk factors that may complicate care. Maternal and environmental factors, such as smoking, drug or alcohol use, gestational diabetes, and GBS, are important considerations when assessing newborns. The placenta, examined by either a nurse or the delivering physician, may also give important clues regarding the health of the infant.

Infants should receive expert postbirth care by a person competent in neonatal resuscitation standards. The formal assessment and documentation of the newborn assessment in a timely fashion is essential. Most institutions use standardized forms and charts based on accepted assessment tools, such as the Apgar and the New Ballard scoring methods. Incomplete or incorrect documentation, as well as a lack of follow-up, may have hazardous implications [183]. Apgar scores should be assigned and may indicate future wellness; however, necessary treatment in critical situations should not wait until a score has been established. Any abnormalities should be reported immediately to the physician and appropriate measures should be taken. By following the same consistent approach with each newborn assessment, the nurse can be confident that the highest level of care has been provided for each infant.