EXAMINATION AT BIRTH
Saturday, August 16, 2008
The extent of the newborn physical examination depends on the condition of the infant and the environment in which the examination is being performed. In the delivery room, the examination consists largely of observation plus auscultation of the chest and inspection for congenital anomalies and birth trauma. Major congenital anomalies are present in 1.5% of live births and account for 20–25% of perinatal and neonatal deaths. Because the infant is recovering from the stress of birth, the examination should not be extensive. The Apgar score (Table 1–5) should be recorded at 1 and 5 minutes of age. In the case of severely depressed infants, a 10-minute score should also be recorded. Although the 1- and 5-minute Apgar scores have almost no predictive value for long-term outcome, serial scores do provide a useful shorthand description of the severity of perinatal depression and the quality of the resuscitative efforts pursued.
The color of the skin is a useful indicator of cardiac output. Because there is normally a high blood flow to the skin, any stress that triggers a catecholamine response produces fairly dramatic changes in skin color secondary to changes in the distribution of the cardiac output and perfusion of the skin. Cyanosis and pallor are two signs reflecting inadequate oxygenation and skin blood flow.
The skeletal examination immediately after delivery serves two purposes: (1) to detect any obvious congenital anomalies and (2) to detect signs of birth trauma, particularly in LGA infants or those born after a protracted second stage of labor—in whom a fractured clavicle or humerus might be found.
The umbilical cord should be examined for the number of vessels. Normally, there are two arteries and one vein. In 1% of deliveries (5–6% of twin deliveries), the cord has only two vessels: an artery and a vein. The latter may be considered a minor anomaly and, as with other minor anomalies, carries a slightly increased risk of associated defects. The placenta is usually examined by the physician delivering it. Small placentas are always associated with small infants. The placental examination emphasizes the identification of membranes and vessels—particularly in multiple gestations—as well as the presence and severity of placental infarcts or evidence of clot (placental abruption) on the maternal side.
GENERAL EXAMINATION IN THE NURSERY
It is important that the examiner have warm hands and a gentle approach. Start with observation, then auscultation of the chest, and then palpation of the abdomen. Examination of the eyes, ears, throat, and hips should be done last, since these maneuvers are most disturbing to the infant. The heart rate should range from 120 to 160 beats/min and the respiratory rate from 30 to 60/min; blood pressure is affected by perinatal asphyxia and the need for mechanical ventilation more so than by gestational age or birth weight. Systolic blood pressure on day 1 ranges from 50 to 70 mm Hg and increases steadily during the first week of life. Note: An irregularly irregular heart rate, usually caused by premature atrial contractions, is common. This irregularity should resolve in the first days of life and is not of pathologic significance.
Skin
Observe for bruising, petechiae (common over the presenting part), meconium staining, and jaundice. Peripheral cyanosis is commonly present when the extremities are cool or the infant is polycythemic. Generalized cyanosis merits immediate evaluation. Pallor may be caused by acute or chronic blood loss or by acidosis. In dark-skinned infants, pallor and cyanosis should be assessed in the oral region and nail beds. Plethora suggests polycythemia. Note vernix caseosa (a whitish, greasy material covering the body that decreases as term approaches) and lanugo (the fine hair covering the preterm infant’s skin). Dry skin with cracking and peeling of the superficial layers is common in postterm infants. Edema may be generalized (hydrops) or localized (eg, on the dorsum of the feet in Turner syndrome). Check for birthmarks such as capillary hemangiomas (lower occiput, eyelids, forehead) and mongolian spot (bluish-black pigmentation over the back and buttocks). Milia—small white keratogenous cysts—can be found scattered over the cheeks, forehead, nose, and nasolabial folds. Miliaria (blocked ducts of sweat glands) occurs in intertriginous areas and on the face or scalp. It can appear as small vesicles (crystallina), small erythematous papules (rubra), or pustules. Erythema toxicum is a benign rash characterized by fleeting erythematous papules and pustules filled with eosinophils. Pustular melanosis leaves pigmented macules when the pustules rupture. The pustules are noninfectious but contain neutrophils. Jaundice presenting in the first 24 hours is considered abnormal and should be evaluated (see Neonatal Jaundice section, below).
Head
Check for cephalohematoma (a swelling over one or both parietal bones contained within suture lines) and caput succedaneum (edema over the presenting part that crosses suture lines). Subgaleal hemorrhages (beneath the scalp) are uncommon but can lead to extensive blood loss into this large potential space with resultant hypovolemic shock. Skull fractures may be linear or depressed and may be associated with cephalohematoma. Check the size and presence of the fontanelles. The anterior fontanelle varies from 1 to 4 cm in any direction, whereas the posterior fontanelle should be less than 1 cm. A third fontanelle is a bony defect along the sagittal suture in the parietal bones and may be a feature of certain syndromes such as trisomy 21. Sutures should be freely mobile. Craniosynostosis is a prematurely fused suture.
Face
Odd facies may be associated with a specific syndrome. Bruising from birth trauma (especially with face presentation) and forceps marks should be identified. Face presentation may be associated with considerable soft tissue swelling around the nose and mouth, causing considerable distortion. Facial nerve palsy is observed when the infant cries; the unaffected side of the mouth moves normally, giving a distorted grimace.
Eyes
Subconjunctival hemorrhages are seen frequently as a result of the birth process. Less commonly, a corneal tear may occur, presenting as a clouded cornea. Ophthalmologic consultation is indicated in such cases. Extraocular movements should be assessed. Occasional uncoordinated eye movements are common, but persistent irregular movements are abnormal. The iris should be inspected for abnormalities such as Brushfield spots (trisomy 21) and colobomas. Examine for the red reflex of the retina. Leukokoria can be caused by glaucoma (cloudy cornea), cataract, or tumor (retinoblastoma). Infants at risk for chorioretinitis (congenital viral infection) should undergo a formal retinal examination with pupils dilated prior to nursery discharge or as an outpatient.
Nose
Examine the nose for size and shape. In utero compression can cause deformities. Because babies under age 1 month are obligate nose breathers, any nasal obstruction (eg, bilateral choanal atresia or stenosis) can cause respiratory distress. Unilateral choanal atresia can be diagnosed by occluding each naris. Purulent nasal discharge at birth suggests congenital syphilis.
Ears
Malformed or malpositioned (low-set or posteriorly rotated) ears are often associated with other congenital anomalies. The tympanic membranes should be visualized.
Mouth
Epithelial (Epstein) pearls are retention cysts along the gum margins and at the junction of the hard and soft palates. Natal teeth may be present and sometimes need to be removed to avoid the risk of aspiration. Check the integrity and shape of the palate; rule out cleft lip and cleft palate. A small mandible and tongue with cleft soft palate is seen with Pierre-Robin syndrome and can result in respiratory difficulty as the tongue occludes the airway. A prominent tongue can be seen in trisomy 21 and Beckwith-Wiedemann syndrome. Excessive drooling suggests esophageal atresia.
Neck
Redundant skin or webbing is seen in Turner syndrome. Sinus tracts may be seen as remnants of branchial clefts. Check for masses: midline (thyroid), anterior to the sternocleidomastoid (branchial cleft cysts), within the sternocleidomastoid (hematoma, torticollis), and posterior to the sternocleidomastoid (cystic hygroma).
Chest & Lungs
Check for fractured clavicles (crepitus, bruising, and tenderness). Increased anteroposterior diameter (barrel chest) can be seen with aspiration syndromes. Check air entry bilaterally and the position of the mediastinum and heart tones. Decreased breath sounds with respiratory distress and a shift in the mediastinum suggests pneumothorax (tension) or a space-occupying lesion (eg, diaphragmatic hernia). With pneumomediastinum, the heart sounds are muffled. Expiratory grunting and decreased air entry are observed in hyaline membrane disease. Rales are not of clinical significance at this age.
Heart
Examination of the heart is described in detail in Chapter 18. Note: Murmurs are commonly present in the first hours and are most often benign. Severe congenital heart disease in the newborn infant may be present with no murmur at all. The two most common presentations of heart disease in the newborn infant are cyanosis and congestive heart failure with abnormalities of pulses. In hypoplastic left heart and critical aortic stenosis, pulses are diminished at all sites. In aortic coarctation and interrupted aortic arch, pulses are diminished in the lower extremities.
Abdomen
Check for softness, distention, and bowel sounds. If polyhydramnios was present or excessive oral secretions are noted, pass a soft catheter into the stomach to rule out esophageal atresia. Palpate for kidneys—most abdominal masses in the newborn infant are associated with kidney disorders (eg, multicystic or dysplastic, hydronephrosis). When the abdomen is relaxed, normal-sized kidneys may be felt but are not prominent. A markedly scaphoid abdomen plus respiratory distress suggests diaphragmatic hernia. Absence of abdominal musculature (prune belly syndrome) may occur in association with renal abnormalities. Check the size of the liver and the spleen. These organs are superficial and discernible by light palpation in the newborn infant. The outline of a distended bladder may be seen and palpated above the pubic symphysis.
Genitalia & Anus
Male and female genitals show characteristics according to gestational age (see Table 1–2). In the female during the first few days, a whitish vaginal discharge with or without blood is normal. Check the patency and location of the anus.
Skeleton
Check for obvious anomalies, for example, the absence of a bone, clubfoot, fusion or webbing of digits, and extra digits. Examine for hip dislocation by attempting to dislocate the femur posteriorly and then abducting the legs to relocate the femur. Look for extremity fractures and for palsies (especially brachial plexus injuries). Rule out myelomeningoceles and other spinal deformities (eg, scoliosis). Arthrogryposis (multiple joint contractures) results from chronic limitation of movement in utero, which may result from lack of amniotic fluid or from a congenital neuromuscular disease.
Neurologic Examination
Normal newborns are endowed with a set of reflexes that facilitate survival (eg, rooting and sucking reflexes), as well as sensory abilities (eg, hearing and smell) that allow them to recognize their mother within a few weeks of birth. Although the retina is well developed at birth, visual acuity is poor (20/400) because of a relatively immobile lens. Acuity improves rapidly over the first 6 months, with fixation and tracking well developed by 2 months.
In examining the newborn, observe resting tone (normal-term newborns should exhibit flexion of the upper and lower extremities) and spontaneous movements. Look for symmetry of movements. Extension of extremities should result in spontaneous recoil to the flexed position. Assess the character of the cry; a high-pitched cry may be indicative of disease of the central nervous system (CNS) (eg, hemorrhage). Hypotonia and a weak cry are indicative of systemic disease or a congenital neuromuscular disorder. Check for newborn reflexes:
The color of the skin is a useful indicator of cardiac output. Because there is normally a high blood flow to the skin, any stress that triggers a catecholamine response produces fairly dramatic changes in skin color secondary to changes in the distribution of the cardiac output and perfusion of the skin. Cyanosis and pallor are two signs reflecting inadequate oxygenation and skin blood flow.
The skeletal examination immediately after delivery serves two purposes: (1) to detect any obvious congenital anomalies and (2) to detect signs of birth trauma, particularly in LGA infants or those born after a protracted second stage of labor—in whom a fractured clavicle or humerus might be found.
The umbilical cord should be examined for the number of vessels. Normally, there are two arteries and one vein. In 1% of deliveries (5–6% of twin deliveries), the cord has only two vessels: an artery and a vein. The latter may be considered a minor anomaly and, as with other minor anomalies, carries a slightly increased risk of associated defects. The placenta is usually examined by the physician delivering it. Small placentas are always associated with small infants. The placental examination emphasizes the identification of membranes and vessels—particularly in multiple gestations—as well as the presence and severity of placental infarcts or evidence of clot (placental abruption) on the maternal side.
GENERAL EXAMINATION IN THE NURSERY
It is important that the examiner have warm hands and a gentle approach. Start with observation, then auscultation of the chest, and then palpation of the abdomen. Examination of the eyes, ears, throat, and hips should be done last, since these maneuvers are most disturbing to the infant. The heart rate should range from 120 to 160 beats/min and the respiratory rate from 30 to 60/min; blood pressure is affected by perinatal asphyxia and the need for mechanical ventilation more so than by gestational age or birth weight. Systolic blood pressure on day 1 ranges from 50 to 70 mm Hg and increases steadily during the first week of life. Note: An irregularly irregular heart rate, usually caused by premature atrial contractions, is common. This irregularity should resolve in the first days of life and is not of pathologic significance.
Skin
Observe for bruising, petechiae (common over the presenting part), meconium staining, and jaundice. Peripheral cyanosis is commonly present when the extremities are cool or the infant is polycythemic. Generalized cyanosis merits immediate evaluation. Pallor may be caused by acute or chronic blood loss or by acidosis. In dark-skinned infants, pallor and cyanosis should be assessed in the oral region and nail beds. Plethora suggests polycythemia. Note vernix caseosa (a whitish, greasy material covering the body that decreases as term approaches) and lanugo (the fine hair covering the preterm infant’s skin). Dry skin with cracking and peeling of the superficial layers is common in postterm infants. Edema may be generalized (hydrops) or localized (eg, on the dorsum of the feet in Turner syndrome). Check for birthmarks such as capillary hemangiomas (lower occiput, eyelids, forehead) and mongolian spot (bluish-black pigmentation over the back and buttocks). Milia—small white keratogenous cysts—can be found scattered over the cheeks, forehead, nose, and nasolabial folds. Miliaria (blocked ducts of sweat glands) occurs in intertriginous areas and on the face or scalp. It can appear as small vesicles (crystallina), small erythematous papules (rubra), or pustules. Erythema toxicum is a benign rash characterized by fleeting erythematous papules and pustules filled with eosinophils. Pustular melanosis leaves pigmented macules when the pustules rupture. The pustules are noninfectious but contain neutrophils. Jaundice presenting in the first 24 hours is considered abnormal and should be evaluated (see Neonatal Jaundice section, below).
Head
Check for cephalohematoma (a swelling over one or both parietal bones contained within suture lines) and caput succedaneum (edema over the presenting part that crosses suture lines). Subgaleal hemorrhages (beneath the scalp) are uncommon but can lead to extensive blood loss into this large potential space with resultant hypovolemic shock. Skull fractures may be linear or depressed and may be associated with cephalohematoma. Check the size and presence of the fontanelles. The anterior fontanelle varies from 1 to 4 cm in any direction, whereas the posterior fontanelle should be less than 1 cm. A third fontanelle is a bony defect along the sagittal suture in the parietal bones and may be a feature of certain syndromes such as trisomy 21. Sutures should be freely mobile. Craniosynostosis is a prematurely fused suture.
Face
Odd facies may be associated with a specific syndrome. Bruising from birth trauma (especially with face presentation) and forceps marks should be identified. Face presentation may be associated with considerable soft tissue swelling around the nose and mouth, causing considerable distortion. Facial nerve palsy is observed when the infant cries; the unaffected side of the mouth moves normally, giving a distorted grimace.
Eyes
Subconjunctival hemorrhages are seen frequently as a result of the birth process. Less commonly, a corneal tear may occur, presenting as a clouded cornea. Ophthalmologic consultation is indicated in such cases. Extraocular movements should be assessed. Occasional uncoordinated eye movements are common, but persistent irregular movements are abnormal. The iris should be inspected for abnormalities such as Brushfield spots (trisomy 21) and colobomas. Examine for the red reflex of the retina. Leukokoria can be caused by glaucoma (cloudy cornea), cataract, or tumor (retinoblastoma). Infants at risk for chorioretinitis (congenital viral infection) should undergo a formal retinal examination with pupils dilated prior to nursery discharge or as an outpatient.
Nose
Examine the nose for size and shape. In utero compression can cause deformities. Because babies under age 1 month are obligate nose breathers, any nasal obstruction (eg, bilateral choanal atresia or stenosis) can cause respiratory distress. Unilateral choanal atresia can be diagnosed by occluding each naris. Purulent nasal discharge at birth suggests congenital syphilis.
Ears
Malformed or malpositioned (low-set or posteriorly rotated) ears are often associated with other congenital anomalies. The tympanic membranes should be visualized.
Mouth
Epithelial (Epstein) pearls are retention cysts along the gum margins and at the junction of the hard and soft palates. Natal teeth may be present and sometimes need to be removed to avoid the risk of aspiration. Check the integrity and shape of the palate; rule out cleft lip and cleft palate. A small mandible and tongue with cleft soft palate is seen with Pierre-Robin syndrome and can result in respiratory difficulty as the tongue occludes the airway. A prominent tongue can be seen in trisomy 21 and Beckwith-Wiedemann syndrome. Excessive drooling suggests esophageal atresia.
Neck
Redundant skin or webbing is seen in Turner syndrome. Sinus tracts may be seen as remnants of branchial clefts. Check for masses: midline (thyroid), anterior to the sternocleidomastoid (branchial cleft cysts), within the sternocleidomastoid (hematoma, torticollis), and posterior to the sternocleidomastoid (cystic hygroma).
Chest & Lungs
Check for fractured clavicles (crepitus, bruising, and tenderness). Increased anteroposterior diameter (barrel chest) can be seen with aspiration syndromes. Check air entry bilaterally and the position of the mediastinum and heart tones. Decreased breath sounds with respiratory distress and a shift in the mediastinum suggests pneumothorax (tension) or a space-occupying lesion (eg, diaphragmatic hernia). With pneumomediastinum, the heart sounds are muffled. Expiratory grunting and decreased air entry are observed in hyaline membrane disease. Rales are not of clinical significance at this age.
Heart
Examination of the heart is described in detail in Chapter 18. Note: Murmurs are commonly present in the first hours and are most often benign. Severe congenital heart disease in the newborn infant may be present with no murmur at all. The two most common presentations of heart disease in the newborn infant are cyanosis and congestive heart failure with abnormalities of pulses. In hypoplastic left heart and critical aortic stenosis, pulses are diminished at all sites. In aortic coarctation and interrupted aortic arch, pulses are diminished in the lower extremities.
Abdomen
Check for softness, distention, and bowel sounds. If polyhydramnios was present or excessive oral secretions are noted, pass a soft catheter into the stomach to rule out esophageal atresia. Palpate for kidneys—most abdominal masses in the newborn infant are associated with kidney disorders (eg, multicystic or dysplastic, hydronephrosis). When the abdomen is relaxed, normal-sized kidneys may be felt but are not prominent. A markedly scaphoid abdomen plus respiratory distress suggests diaphragmatic hernia. Absence of abdominal musculature (prune belly syndrome) may occur in association with renal abnormalities. Check the size of the liver and the spleen. These organs are superficial and discernible by light palpation in the newborn infant. The outline of a distended bladder may be seen and palpated above the pubic symphysis.
Genitalia & Anus
Male and female genitals show characteristics according to gestational age (see Table 1–2). In the female during the first few days, a whitish vaginal discharge with or without blood is normal. Check the patency and location of the anus.
Skeleton
Check for obvious anomalies, for example, the absence of a bone, clubfoot, fusion or webbing of digits, and extra digits. Examine for hip dislocation by attempting to dislocate the femur posteriorly and then abducting the legs to relocate the femur. Look for extremity fractures and for palsies (especially brachial plexus injuries). Rule out myelomeningoceles and other spinal deformities (eg, scoliosis). Arthrogryposis (multiple joint contractures) results from chronic limitation of movement in utero, which may result from lack of amniotic fluid or from a congenital neuromuscular disease.
Neurologic Examination
Normal newborns are endowed with a set of reflexes that facilitate survival (eg, rooting and sucking reflexes), as well as sensory abilities (eg, hearing and smell) that allow them to recognize their mother within a few weeks of birth. Although the retina is well developed at birth, visual acuity is poor (20/400) because of a relatively immobile lens. Acuity improves rapidly over the first 6 months, with fixation and tracking well developed by 2 months.
In examining the newborn, observe resting tone (normal-term newborns should exhibit flexion of the upper and lower extremities) and spontaneous movements. Look for symmetry of movements. Extension of extremities should result in spontaneous recoil to the flexed position. Assess the character of the cry; a high-pitched cry may be indicative of disease of the central nervous system (CNS) (eg, hemorrhage). Hypotonia and a weak cry are indicative of systemic disease or a congenital neuromuscular disorder. Check for newborn reflexes:
- Sucking reflex in response to a nipple or the examiner’s finger in the mouth. This reflex is observed by 14 weeks’ gestation.
- Rooting reflex: Head turns to the side of a facial stimulus. This reflex develops by 28 weeks’ gestation.
- Traction response: The infant is pulled by the arms to a sitting position. Initially, the head lags, then with active flexion comes to the midline briefly before falling forward.
- Palmar grasp with placement of the examiner’s finger in the palm. This reflex develops by 28 weeks’ gestation and disappears by age 4 months.
- Deep tendon reflexes: Several beats of ankle clonus and an upgoing Babinski reflex may be normal.
- Placing: Rub the dorsum of one foot on the underside of a surface. The infant will flex the knee and bring the foot up.
- Moro (startle) reflex: Hold the infant and support the head. Allow the head to drop 1–2 cm suddenly. The arms will abduct at the shoulder and extend at the elbow. Adduction will follow. The hands show a prominent spreading or extension of the fingers. This reflex develops by 28 weeks’ gestation (incomplete) and disappears by age 3 months.
- Tonic neck reflex: Forcibly turn the infant’s head to one side, and the arm and leg on that side extend while the opposite arm and leg flex (“fencing position”). This reflex disappears by age 8 months.
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