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Routine neurological examination of the newborn
Serials
Central nervous system
Routine neurological examination of the newborn
L. S. De Vries ence, as you will find that the examination of a full term infant is quite different from that of a preterm infant, even when the preterm infant is examined at 40 weeks postmenstrual age. Try to examine the baby before he is due for a feed. When the baby is asleep, it is useful to wake him up, using a rattle, to reassure yourself that the infant is responding to sound. Do not immediately start touching the baby. You will get a lot of information just by watching the baby move spontaneously. Observe whether his movements are slow and gradual with waxing and waning, whether he is moving all his limbs, or whether he is relaxed or is crying a lot and decide if the cry is normal or high pitched. Look at the face, for normal facial expression and for evidence of like a facial palsy following a forceps delivery. When you have seen the baby move for a while in the supine position, you will have obtained information about the posture, which will be mainly flexed in a full term infant. Then gently start touching the baby, feel the fontanelle, and start assessing the muscle tone in all limbs. Pull the baby to sit, noticing the degree of head lag, which is normally still present in a full term infant. When held sitting assess whether the infant attempts to bring his head up and whether he is able to bring the head forward when you extend it. Then feel how the baby lies on your hand when held in ventral suspension. Does he try to lift his head, are the legs and arms flexed? Putting the baby prone, observe whether he rolls his head from side to side and in the supine position, try to get the baby to follow a bright red object. A full term infant should be able to follow in the horizontal as well as the vertical plane. Having almost finished with the examination, you may now attempt to elicit a Moro reflex. Holding the child, one hand supporting the spine, the other hand supporting the head, the Moro response is elicited by suddenly releasing one’s hold of the head. The Moro reflex consists of abduction
With an ultrasound machine available in most neonatal intensive care units, it may be considered no longer necessary to perform a neurological examination of the newborn, a procedure which has often in the past been regarded as difficult and unreliable. However, it was recently shown by Prechtl that pure observation of the movement pattern of a premature infant, may yield important information. Together with Cioni’ he reported how they made video recordings of spontaneous movements of premature infants in an incubator for an hour. When replaying the tape, the gross movements involving the whole body were noted to have a gradual onset and end with waxing and waning in intensity, force and speed in the normal infants, while infants with severe brain lesions showed disorganisation of general movements, with a sudden onset, a stereotyped appearance lacking variability, elegance and fluency. They concluded that this qualitative assessment of motor activity has a high predictive value for subsequent neurodevelopment and stressed the value of pure observation. A more commonly used neurological assessment of premature infants was devised by Dubowitz and Dubowitz.’ This proforma enables us to study premature infants sequentially, thus recording the changes in tone and movement, primitive reflexes, hearing and vision, response to handling and stimulation from birth up till 40 weeks postmenstrual age. This easy examination can be used by junior doctors who do not have any expertise in neonatal neurological assessment. The best way to get experience in examining a newborn infant, is by going to the maternity ward and examine some normal full term infants. Do not start examining preterm infants without this experiLinda S. De V&s MD, F%D,Department of Neonatology, Wilhelmina Children Hospital, Nieuwe Gracht 137, 3512 LK Utrecht, The Netherlands. Correspondence and requests for offprints to LSDV. Current Poediafrics (1991) 1, 183- 185 C 1991 Longman Group UK Ltd
183
184
CURRENT
PAEDIATRICS
followed by adduction of the arms. You will not be able to elicit the response when the baby has his hands clenched. The Moro response should be present and symmetrical. Having examined quite a few normal full term infants, the next step is to look for a preterm infant who is not on the ventilator and has no abnormalities on cranial ultrasound. Once again take enough time to watch spontaneous movements, which can be very elegant in a preterm infant. Comparing the assessment with a full term infant you will find, that the preterm infant is more placid, does not cry as easily, as long as the examination is performed slowly and carefully. The tone in the limbs is lower and the tone in the arms should be ‘lower than in the legs. The tone gradually increases with gestational age, but even when examined at 40 weeks postmenstrual age, an infant born at 30 weeks gestation, will have a different tone pattern. Especially note the tendency to extend the legs intermittently when supine and when held in ventral suspension. Keep in mind, that the child has not been restricted during the last 10 weeks and do not misinterpret this extension for an early sign of spastic diplegia. From 32 weeks gestational age onwards it is usually possible to get the preterm infant to focus and follow briefly in the horizontal plane. The Moro response is different from that seen in the full term infant. Initially you will note only abduction but with increasing gestational age, less abduction is noted with a gradual increase of adduction. Irritability, excessive tremors or startles, an abnormal Moro response and increased tone especially of the arms, but also of the legs can be of serious significance, especially when seen on more than one occasion. Combining the Dubowitz assessment with simultaneous imaging studies have made it possible to recognise certain patterns of neurological behaviour, both for premature infants suffering from peri- or intraventricular haemorrhages, as well as for infants developing cystic leukomalacia.
trunk tone are the last to recover. Roving eye movements can be noted during this phase. Infants with intraventricular haemorrhages tend to be hypotonic during the first year of life, but this usually normalises during the second year of life. A hemiplegia usually becomes apparent during the first year of life, in those who develop a unilateral porencephalic cyst following parenchymal involvement. Cystic periventricular leukomalacia (PVL)
The premature infant who develops cystic leukomalacia also shows a recognisable pattern of sequential clinical signs4 In the acute phase, when echogenic areas are identified using ultrasound, the infant tends to be hypotonic and lethargic, but with age appropriate auditory and visual responses. Over the subsequent weeks an improvement is noted in the infant’s tone and he appears to have a normal neurological behaviour for a short period of time. Following the appearance of cysts in the previously echogenic areas on ultrasonography a very characteristic clinical picture emerges. The infant becomes increasingly irritable and is very difficult to pacify. The tone becomes high with a marked increase in flexion of the arms and extension of the legs. In a sitting position the infant is now inclined to show neck extension. The movement pattern shows a lack of variability and the infant is tremulous with a lot of spontaneous startles. Finger and toe posture are often abnormal, with spontaneous dorsiflexion of the big toe and flexion of the index finger. The Moro reaction is usually abnormal with only extension without abduction or adduction (Table 1). These infants subsequently go on to develop cerebral palsy with more leg than arm involvement and a reasonable intellect. The neurodevelopmental outcome of infants with cystic leukomalacia is much poorer than premature infants who suffer a large intraventricular haemorrhage with or without unilateral parenchymal involvement.’ Hypoxic-ischaemic
Periventricular-intraventricular haemorrhage (PVHIVH)
Dubowitz et al3 were able to recognise three phases in infants who developed an intraventricular haemorrhage. Phase one: preceding the haemorrhage or at the time of onset, shows the infant to be hypertonic, excessively mobile with tremors, startles and irritability. The tendon reflexes are brisk, the Moro abnormal and visual/auditory responses absent. Once the haemorrhage is established (phase two) there is a decrease in tone and motility as well as a relatively tighter popliteal angle. There is poor reactivity and visual orientation is absent. Phase three: the phase of recovery, shows a normalisation of tone and subsequent improvement in motility. Auditory and subsequently visual orientation recover. Head and
encephalopathy (HIE)
In contrast to the premature infant, who tends to get classified according to the type of ultrasound abnor-
Table 1 Neurological signs commonly present in infants with large haemorrhages or cystic leukomalacia Large Haemorrhage
Cystic Leukomalacia
Acute Phase
1 motility 1 tone tight PA
1 motility 1 tone
40 wks PMA
1 tone f asymmetry + + head lag + neck extension
tt tone + + irritability no head lag + + neck extension
PMA = postmenstrual age; PA = popliteal angle
NEUROLOGICAL
mality, the full term infant is usually classified according to the degree of encephalopathy. Sarnat and Sarnat6 described three clinical stages of severity of HIE, which was recently simplified by Levene et al7 The infants with mild encephalopathy appear to be hyperalert often with staring of the eyes. Clinically apparent seizures do not occur. The infant may have problems feeding due to an initially weak sucking reflex. Symptoms usually resolve within 24 h and should have disappeared within 48 h. Infants with moderate encephalopathy show a very different behaviour. They are lethargic and tube feeding is usually necessary. Convulsions usually develop within the first 24 h, but are easily treated using standard drugs such as phenobarbitone. Considerable improvement is usually noted within the first week of life. The infant with severe encephalopathy is stuporose or comatose and usually requires ventilatory support. They are very hypotonic and seizures are frequent and difficult to treat. Recovery is slow and may take up to 6 weeks. There is a good correlation between the degree of encephalopathy and subsequent neurodevelopmental outcome. Almost all the infants with mild encephalopathy are normal at follow UP.~-~ Seventy-five percent of the infants with moderate encephalopathy do well at follow up but only O-25% are subsequently found to be normal following severe encephalopathy. Imaging studies of the full term infant may show a variety of abnormalities such as subcortical cystic leukomalacia, cortical cysts or bright thalami,9 which are of predictive value of a poor prognosis, but most of the important changes occur after the clinical and electrophysiological picture has become clear. Electroencephalography (EEG) and evoked poten-
EXAMINATION
185
tials, especially somatosensory evoked potentials can also provide important information in infants with HIE. The isoelectric EEG or the burst suppression pattern carry a poor prognosis6 and coincide with a severely delayed or absent somatosensory potentials. In spite of the advances of modern technology, clinical neurological assessment and the qualitative assessment of general movements should still play an important role in our day to day care of the newborn infant.
References I. Cioni G, Prechtl HFR. Preterm and early postterm motor
2.
3.
4.
5.
6. 1.
8.
9.
behaviour in low-risk premature infants. Early Hum Dev 1990; 23: 159-191. Dubowitz LMS, Dubowitz V. The neurological assessment of the premature and full-term newborn infant. Clinics in Dev Medicine No 79. SIMP/Heinemann, London. Dubowitz LMS, Levene MI, Morante A, Palmer P, Dubowitz V. Neurological signs in neonatal intraventricular haemorrhage - a correlation with real-time ultrasound. J Pediatr 1981; 99: 127-132. Dubowitz LMS. Clinical assessment of the infant nervous system. In: Levene MI, Bennett MJ and Punt J ed; Edinburgh, Churchill Livingstone; 1988; 41-58. De Vries LS, Dubowitz LMS, Dubowitz V, Kaiser A, Lary S, Silverman M, Whitelaw A, Wigglesworth JS. Cranial ultrasound: a reappraisal. Lancet 1985; ii: 137-140. Sarnat HB, Sarnat MS. Neonatal encephalopathy following fetal distress. Arch Neural 1976; 33: 696-705. Levene MI, Kornberg J, Williams IHC. The incidence and severity of post asphyxial encephalopathy in full term infants. Early Hum Dev 1985; 11:21-28. Finer NN, Richards RT, Peters KL. Hypoxic-ischemic encephalopathy in term neonates: perinatal factors and outcome. J Pediatr 1981; 98: 112-l 17. Shen EY, Huang CC, Chyou SC, Hung HY, Hsu CH, Huang FY. Sonographic findings of the bright thalamus. Arch Dis Child 1986; 64: 452-458.
Central nervous system
Routine neurological examination of the newborn
L. S. De Vries ence, as you will find that the examination of a full term infant is quite different from that of a preterm infant, even when the preterm infant is examined at 40 weeks postmenstrual age. Try to examine the baby before he is due for a feed. When the baby is asleep, it is useful to wake him up, using a rattle, to reassure yourself that the infant is responding to sound. Do not immediately start touching the baby. You will get a lot of information just by watching the baby move spontaneously. Observe whether his movements are slow and gradual with waxing and waning, whether he is moving all his limbs, or whether he is relaxed or is crying a lot and decide if the cry is normal or high pitched. Look at the face, for normal facial expression and for evidence of like a facial palsy following a forceps delivery. When you have seen the baby move for a while in the supine position, you will have obtained information about the posture, which will be mainly flexed in a full term infant. Then gently start touching the baby, feel the fontanelle, and start assessing the muscle tone in all limbs. Pull the baby to sit, noticing the degree of head lag, which is normally still present in a full term infant. When held sitting assess whether the infant attempts to bring his head up and whether he is able to bring the head forward when you extend it. Then feel how the baby lies on your hand when held in ventral suspension. Does he try to lift his head, are the legs and arms flexed? Putting the baby prone, observe whether he rolls his head from side to side and in the supine position, try to get the baby to follow a bright red object. A full term infant should be able to follow in the horizontal as well as the vertical plane. Having almost finished with the examination, you may now attempt to elicit a Moro reflex. Holding the child, one hand supporting the spine, the other hand supporting the head, the Moro response is elicited by suddenly releasing one’s hold of the head. The Moro reflex consists of abduction
With an ultrasound machine available in most neonatal intensive care units, it may be considered no longer necessary to perform a neurological examination of the newborn, a procedure which has often in the past been regarded as difficult and unreliable. However, it was recently shown by Prechtl that pure observation of the movement pattern of a premature infant, may yield important information. Together with Cioni’ he reported how they made video recordings of spontaneous movements of premature infants in an incubator for an hour. When replaying the tape, the gross movements involving the whole body were noted to have a gradual onset and end with waxing and waning in intensity, force and speed in the normal infants, while infants with severe brain lesions showed disorganisation of general movements, with a sudden onset, a stereotyped appearance lacking variability, elegance and fluency. They concluded that this qualitative assessment of motor activity has a high predictive value for subsequent neurodevelopment and stressed the value of pure observation. A more commonly used neurological assessment of premature infants was devised by Dubowitz and Dubowitz.’ This proforma enables us to study premature infants sequentially, thus recording the changes in tone and movement, primitive reflexes, hearing and vision, response to handling and stimulation from birth up till 40 weeks postmenstrual age. This easy examination can be used by junior doctors who do not have any expertise in neonatal neurological assessment. The best way to get experience in examining a newborn infant, is by going to the maternity ward and examine some normal full term infants. Do not start examining preterm infants without this experiLinda S. De V&s MD, F%D,Department of Neonatology, Wilhelmina Children Hospital, Nieuwe Gracht 137, 3512 LK Utrecht, The Netherlands. Correspondence and requests for offprints to LSDV. Current Poediafrics (1991) 1, 183- 185 C 1991 Longman Group UK Ltd
183
184
CURRENT
PAEDIATRICS
followed by adduction of the arms. You will not be able to elicit the response when the baby has his hands clenched. The Moro response should be present and symmetrical. Having examined quite a few normal full term infants, the next step is to look for a preterm infant who is not on the ventilator and has no abnormalities on cranial ultrasound. Once again take enough time to watch spontaneous movements, which can be very elegant in a preterm infant. Comparing the assessment with a full term infant you will find, that the preterm infant is more placid, does not cry as easily, as long as the examination is performed slowly and carefully. The tone in the limbs is lower and the tone in the arms should be ‘lower than in the legs. The tone gradually increases with gestational age, but even when examined at 40 weeks postmenstrual age, an infant born at 30 weeks gestation, will have a different tone pattern. Especially note the tendency to extend the legs intermittently when supine and when held in ventral suspension. Keep in mind, that the child has not been restricted during the last 10 weeks and do not misinterpret this extension for an early sign of spastic diplegia. From 32 weeks gestational age onwards it is usually possible to get the preterm infant to focus and follow briefly in the horizontal plane. The Moro response is different from that seen in the full term infant. Initially you will note only abduction but with increasing gestational age, less abduction is noted with a gradual increase of adduction. Irritability, excessive tremors or startles, an abnormal Moro response and increased tone especially of the arms, but also of the legs can be of serious significance, especially when seen on more than one occasion. Combining the Dubowitz assessment with simultaneous imaging studies have made it possible to recognise certain patterns of neurological behaviour, both for premature infants suffering from peri- or intraventricular haemorrhages, as well as for infants developing cystic leukomalacia.
trunk tone are the last to recover. Roving eye movements can be noted during this phase. Infants with intraventricular haemorrhages tend to be hypotonic during the first year of life, but this usually normalises during the second year of life. A hemiplegia usually becomes apparent during the first year of life, in those who develop a unilateral porencephalic cyst following parenchymal involvement. Cystic periventricular leukomalacia (PVL)
The premature infant who develops cystic leukomalacia also shows a recognisable pattern of sequential clinical signs4 In the acute phase, when echogenic areas are identified using ultrasound, the infant tends to be hypotonic and lethargic, but with age appropriate auditory and visual responses. Over the subsequent weeks an improvement is noted in the infant’s tone and he appears to have a normal neurological behaviour for a short period of time. Following the appearance of cysts in the previously echogenic areas on ultrasonography a very characteristic clinical picture emerges. The infant becomes increasingly irritable and is very difficult to pacify. The tone becomes high with a marked increase in flexion of the arms and extension of the legs. In a sitting position the infant is now inclined to show neck extension. The movement pattern shows a lack of variability and the infant is tremulous with a lot of spontaneous startles. Finger and toe posture are often abnormal, with spontaneous dorsiflexion of the big toe and flexion of the index finger. The Moro reaction is usually abnormal with only extension without abduction or adduction (Table 1). These infants subsequently go on to develop cerebral palsy with more leg than arm involvement and a reasonable intellect. The neurodevelopmental outcome of infants with cystic leukomalacia is much poorer than premature infants who suffer a large intraventricular haemorrhage with or without unilateral parenchymal involvement.’ Hypoxic-ischaemic
Periventricular-intraventricular haemorrhage (PVHIVH)
Dubowitz et al3 were able to recognise three phases in infants who developed an intraventricular haemorrhage. Phase one: preceding the haemorrhage or at the time of onset, shows the infant to be hypertonic, excessively mobile with tremors, startles and irritability. The tendon reflexes are brisk, the Moro abnormal and visual/auditory responses absent. Once the haemorrhage is established (phase two) there is a decrease in tone and motility as well as a relatively tighter popliteal angle. There is poor reactivity and visual orientation is absent. Phase three: the phase of recovery, shows a normalisation of tone and subsequent improvement in motility. Auditory and subsequently visual orientation recover. Head and
encephalopathy (HIE)
In contrast to the premature infant, who tends to get classified according to the type of ultrasound abnor-
Table 1 Neurological signs commonly present in infants with large haemorrhages or cystic leukomalacia Large Haemorrhage
Cystic Leukomalacia
Acute Phase
1 motility 1 tone tight PA
1 motility 1 tone
40 wks PMA
1 tone f asymmetry + + head lag + neck extension
tt tone + + irritability no head lag + + neck extension
PMA = postmenstrual age; PA = popliteal angle
NEUROLOGICAL
mality, the full term infant is usually classified according to the degree of encephalopathy. Sarnat and Sarnat6 described three clinical stages of severity of HIE, which was recently simplified by Levene et al7 The infants with mild encephalopathy appear to be hyperalert often with staring of the eyes. Clinically apparent seizures do not occur. The infant may have problems feeding due to an initially weak sucking reflex. Symptoms usually resolve within 24 h and should have disappeared within 48 h. Infants with moderate encephalopathy show a very different behaviour. They are lethargic and tube feeding is usually necessary. Convulsions usually develop within the first 24 h, but are easily treated using standard drugs such as phenobarbitone. Considerable improvement is usually noted within the first week of life. The infant with severe encephalopathy is stuporose or comatose and usually requires ventilatory support. They are very hypotonic and seizures are frequent and difficult to treat. Recovery is slow and may take up to 6 weeks. There is a good correlation between the degree of encephalopathy and subsequent neurodevelopmental outcome. Almost all the infants with mild encephalopathy are normal at follow UP.~-~ Seventy-five percent of the infants with moderate encephalopathy do well at follow up but only O-25% are subsequently found to be normal following severe encephalopathy. Imaging studies of the full term infant may show a variety of abnormalities such as subcortical cystic leukomalacia, cortical cysts or bright thalami,9 which are of predictive value of a poor prognosis, but most of the important changes occur after the clinical and electrophysiological picture has become clear. Electroencephalography (EEG) and evoked poten-
EXAMINATION
185
tials, especially somatosensory evoked potentials can also provide important information in infants with HIE. The isoelectric EEG or the burst suppression pattern carry a poor prognosis6 and coincide with a severely delayed or absent somatosensory potentials. In spite of the advances of modern technology, clinical neurological assessment and the qualitative assessment of general movements should still play an important role in our day to day care of the newborn infant.
References I. Cioni G, Prechtl HFR. Preterm and early postterm motor
2.
3.
4.
5.
6. 1.
8.
9.
behaviour in low-risk premature infants. Early Hum Dev 1990; 23: 159-191. Dubowitz LMS, Dubowitz V. The neurological assessment of the premature and full-term newborn infant. Clinics in Dev Medicine No 79. SIMP/Heinemann, London. Dubowitz LMS, Levene MI, Morante A, Palmer P, Dubowitz V. Neurological signs in neonatal intraventricular haemorrhage - a correlation with real-time ultrasound. J Pediatr 1981; 99: 127-132. Dubowitz LMS. Clinical assessment of the infant nervous system. In: Levene MI, Bennett MJ and Punt J ed; Edinburgh, Churchill Livingstone; 1988; 41-58. De Vries LS, Dubowitz LMS, Dubowitz V, Kaiser A, Lary S, Silverman M, Whitelaw A, Wigglesworth JS. Cranial ultrasound: a reappraisal. Lancet 1985; ii: 137-140. Sarnat HB, Sarnat MS. Neonatal encephalopathy following fetal distress. Arch Neural 1976; 33: 696-705. Levene MI, Kornberg J, Williams IHC. The incidence and severity of post asphyxial encephalopathy in full term infants. Early Hum Dev 1985; 11:21-28. Finer NN, Richards RT, Peters KL. Hypoxic-ischemic encephalopathy in term neonates: perinatal factors and outcome. J Pediatr 1981; 98: 112-l 17. Shen EY, Huang CC, Chyou SC, Hung HY, Hsu CH, Huang FY. Sonographic findings of the bright thalamus. Arch Dis Child 1986; 64: 452-458.