Asphyxia of the newborn. Birth trauma

1. Asphyxia of the newborn.
Birth trauma

2. Definition
 WHO: Asphyxia is incapacity of newborn
to begin or to support spontaneous
respiration after delivery due to
breaching of oxygenation during labor
and delivery
Asphyxia is absense or ineffective
respiration of newborn of 1 minute old
with Apgar score less than 4

3. Definition
Ukraine: Asphyxia of newborn as a
nosological form is conditioned by causes
when severe maternal-placental and (or)
umbilical blood flow is disturbed
and leads to development
of metabolic acidosis

4. Asphyxia
 Asphyxia: means “a stopping of the pulse”, but more useful
is a definition of impaired or interrupted gas
exchange.
 These situations can take place:
 a. Intrauterine: the gas exchange depends on the
function of placenta, and the blood-flow in the umbilical
vessels.
 b. Postnatal: after delivery the gas exchange takes
place in the pulmonary vesicles or alveoli and depends on
the function of the heart, lungs and brain.

5. Sponsored
Medical Lecture Notes – All Subjects
USMLE Exam (America) – Practice

6. Causes of Asphyxia
Fetal hypoxia:
 Mother: hypoventilation during anesthesia, cyanotic heart
disease, respiratory failure or carbon monoxide poisoning.
 Low maternal blood pressure as a result of the hypotension
that may cause compression of the vena cava & aorta by the
gravid uterus
 Premature separation of the placenta; placenta previa
 Impedance to the circulation of blood through the umbilical
cord as a result of compression or knotting of the cord
 Uterine vessel vasoconstriction by cocaine, smoking
 Placental insufficiency from numerous causes, including
gestosis, eclampcia, toxemia, postmaturity
 Extremes in maternal age (< 20 years or >35 years)
 Preterm or postterm gestation.

7. Causes of Asphyxia
Intrapartus asphyxia:
 More frequently inadequate obstetric aid
 Using forceps, vacuum extraction, cresteller,
caesarean section (immediate)
 Trauma: narrow pelvis, malpresentation
 Extremely rapid or prolonged labor
 Multiple gestation
 Drugs depression of CNS: anesthesia, sedatives &
analgesics
 Meconium-stained amniotic fluid

8. Causes of Asphyxia
Postnatal hypoxia:
 Anemia due to severe hemorrhage or hemolytic
disease
 Shock from adrenal hemorrhage, intraventricular
hemorrhage, overwhelming infection, massive blood
loss
 Failure to breathe due to a cerebral defect, narcosis or
injury
 Failure of oxygenation resulting from of cyanotic
congenital heart disease or deficient pulmonary
function

9. Predisposing risk
factors for asphyxia are:
 Multiple gestation;
 Placental abruption;
 Placenta previa;
 Preeclampsia;
 Meconium-stained amniotic fluid;
 Fetal bradycardia;
 Prolonged rupture of fetal membranes;
 Extremes in maternal age (senior 35 y, junior 20 y);
 Maternal diabetes;
 Maternal use of illicit drugs;

10. Apgar Score of the Newborn
SIGNSCORE 0 1 2
Heart rate Absent <100 beats/min >100 beats/min
Respiratory effort Absent Weak, irregular Strong cry
Muscle tone Flaccid Some flexion Well
Reflex irritability
(response to
catheter in nostril)
No Grimace Cough or
sneeze
Skin colour Blue,
pale
extremities
blue
pink

11. Postnatal symptoms of ASPHYXIA
MILD ASPHYXIA
 ° The infant who experiences mild
asphyxia initially will be depressed.
This is followed by a period of
hyperalertness, which resolves within
1 or 2 days.
° Clinical symptoms:
 hyperalertness (jitteriness),
 increased irritability and tendon
reflexes,
 exaggerated Moro response;
 ° There are no local signs
 ° The prognosis is excellent for normal
(good) outcome.

12. CRITERIA OF MODERATE ASPHYXIA
° The infant who experiences moderate
asphyxia will be very depressed. This
is followed by a prolonged period of
hyperalertness and hyperreflexia.
° Clinical symptoms:
 lethargy, hypotonia
 suppressed reflexes with or without
seizures
 Generalised seizures often occur 12 to
24 hours after episode of asphyxia,
but are controlled easily, resolving in
a few days regarding of therapy.
 ° The prognosis is variable (20-40%
with abnormal outcome).

13. CRITERIA OF SEVERE ASPHYXIA
 ° Severe metabolic or mix
acidosis pH ≤ 7.00 in arterial
blood of umbilical vessels;
° Assessment by Apgar is 0-3
during more than 5 minutes;
° Neurological symptoms such as
general hypotonia, lethargy,
coma, seizures, brainstem,
autonomous dysfunction;
° Evidence of multiorgan
system dysfunction in the
immediate neonatal period - damage
of vital organs (lungs, heart and others)
in fetus or newbon;

14. CRITERIA OF SEVERE ASPHYXIA
 ° Severe asphyxia is associated
with coma, intractable seizures
activity, cerebral oedema,
intracranial haemorrhage.
 ° The infant often became
progressively more depressed
over the first 1 to 3 days, as a
cerebral oedema develops, and
death may occur during this
period.
 Survival is usually associated
with poor long-term outcome
(100% with abnormal outcome);

15. Acute complications
associated with Asphyxia
 hypoxic-ischemic encephalopathy (HIE)
 hypotension
 seizures
 persistent pulmonary hypertension
 hypoxic cardiomyopathy
 necrotizing enterocolitis
 acute tubular necrosis
 adrenal hemorrhage and necrosis
 Hypoglycemia, polycytemia
 disseminated intravascular coagulation

16. Hypoxic-ischemic cerebral injury –
HIE (encephalopathy)
 Is caused by a combination of hypoxemia,
ischemia, that results in a decreased supply
of oxygen to cerebral tissue
 During perinatal asphyxia, birth trauma,
hypercapnia and acidosis may contribute
further to the cerebral insult.

17. Sarnat criteria
 Level of consciousness
 Neuromuscular control
 Muscle tone
 Posture
 Stretch reflexes
 Segmental myoclonus
 Complex reflexes: Suck, Moro,
oculovestibular tonic neck
 Autonomic function

18.  Pupils
 Respirations
 Heart rate
 Bronchial & salivary secretions
 Gastrointestinal motility
 Seizures
 EEG
 Duration of symptoms
Sarnat criteria

20.  Clinical symptoms and metabolic derangement –
blood sample from the umbilical artery - low pH (< 7, 00) -
indicates the intrapartum asphyxia.
 Renal and/or cardiac failure
 Assessment of the brain: EEG
Serial recordings are almost necessary.
Low voltage. Burst-suppression patterns or electrical
inactivity are associated with bad prognosis.
Rapid resolution of EEG abnormalities and/or normal
interictal EEG are associated with a good prognosis.
DIAGNOSIS

21. Ultrasound and Doppler technique
 Ultrasound: to measure the growth of the fetus. The growth
retarded fetus is in a great risk of developing asphyxia.
Ultrasound can be useful in premature newborns.
 Doppler techniques: to measure the blood flow in the umbilical
vessels or aorta. A low flow or decreasing flow indicates a fetus
in risk of asphyxia.
 Computed tomography: CT is of major value both
acutely during the neonatal period and later in childhood.
The optimal timing of CT scanning is between 2 and 4 days.

22. ABC resuscitation
 A- Airways (maintenance of
passableness of airway)
 B- breathing (stimulation of breathing)
 C- circulation (support of circulation)
 D-drug

23. ABC resuscitation
 Step A- immediately after delivery the
infant’s head should be placed in a
neutral or slightly extended position
 Roller towel under the shoulders

24. And airway established by clearing the
mouth, then the nose by rubber bag


25. If it is inadequate we must use step B.
At first the tactile stimulation should
be given to newborn,
for example - gentle flicking of the feet or heel

26. ABC resuscitation
or rubbing of the back

27. If meconium is present in amniotic fluid,
after sucking of mouth and nose we must
suck a pharynx by tube after laryngoscope

28. If these measures are inadequate,
mechanical ventilation should be initiated,
using mask and bag ventilation

29. If ventilation is adequate supplemental
oxygen may be given to improve
heart rate or skin colour

30. If mechanical ventilation does not improve the
respiration, heart rate or colour skin,
the following step is “C”-circulation.
At first the assessment of heart rate is necessary

31. If heart rate is less than 60 beats/minute, or
between 60 and 80 beats and is not improving,
cardiac compression must be performed

32. ABC resuscitation
 Big fingers must lie on the sternum, other fingers
should lie under the back of newborn

33. ABC resuscitation
 If heart rate is less then 80 beats per minute the
cardiac compression should be continued.
 If heart rate is 80 beats per minute or more the
cardiac compression should be stopped .

34. Birth trauma
 The term “Birth trauma” is used to
denote mechanical and anoxic trauma
incurred by the infant during labor
and delivery.
The process of birth is associated
with compressions, contractions,
and tractions.

35. Birth trauma
 When fetal size, presentation or
neurological immaturity complicate
this event, such intrapartum forces
may lead to
tissue damage,
edema,
hemorrhage
or fracture in the neonate.

36. The risk of birth injury
 Small maternal stature
 Maternal pelvic anomalies
 Extremely rapid
 Prolonged labor
 Using forceps, vacuum extraction
 Versions and extraction
 Deep transverse arrest of descent of presenting
part of fetus
 Oligohydramnions
 Abnormal presentation (i.e. breech)

37. The risk of birth injury
 Very low birth weight infant or extreme
premature
 Postmature infant(> 42 week of gestation)
 Cesarean section
 Fetal macrosomia
 Large fetal head
 Fetal anomalies
(see teratoma)

38. Classification of birth injuries
 I. Soft-tissue injuries
 - caput succedaneum
 - subcutaneous and retinal hemorrhage,
petechia
 - ecchymoses and subcutaneous fat necrosis

39. Classification of birth
injuries
 II. Cranial injuries
 cephalohematoma
 fractures of the skull

40. Classification of birth
injuries
 III. Intracranial hemorrhage
 subdural hemorrhage
 subarachnoid hemorrhage
 intra- and periventricular
hemorrhage
 parenchyma hemorrhage

41. Classification of birth injuries
 IV. Spine and spinal cord
 fractures of vertebra
 Erb-Duchenne paralysis
 Klumpke paralyses
 Phrenic nerve paralyses
 Facial nerves palsy

42. Classification of birth
injuries
V. Peripheral nerve injuries
VI. Viscera (rupture of liver, spleen and adrenal
hemorrhage)
 VII. Fractures of bones.

43. Birth trauma
 Petechiae and ecchymosis are common
manifestation of birth trauma in the newborn. Petechiae of
the skin of the head and neck are common. These lesions
resolve spontaneously within 1 week.
 They are caused by a sudden increase in intrathoracic
pressure during labor when the fetus passes through the
birth canal.
 They are temporary and are the result of normal course of
delivery.
 If the etiology is uncertain, studies to rule out coagulation
disorders or infections etiology are indicated.

44. Birth trauma
 Caput succedaneum is a subcutaneous extraperiosteal
fluid collection in the presenting part of fetus
 is caused by infiltration of subcutaneous soft tissue in the
presenting part resulting from pressure in birth canal
 with poorly defined margins
 it may extend across the midline over suture lines
 This swelling is resolved rather quickly within several
days post partum.

45. Cephalohematoma
 is a subperiosteal collection of blood resulting
from rupture of the blood vessels between the
skull and pereostium
 its does not extend over suture lines between
adjacent bones.
 Its occurrence is commonly on one side of the
head
 The extent of hemorrhage may be severe enough to
present as anemia and hypotension with secondary
hyperbilirubinemia.

46. Birth trauma

47. • It may be a focus of infection leading to meningitis,
particularly when there is a concomitant skull fracture.
Skull X-rays should be obtained if there are CNS
symptoms,
if the hematoma is very large or if the delivery was very
difficult.
 Resolution occurs over 1 to 2 month, occasionally
with residual calcification as a thrombus.

48. Birth trauma
 INTRACRANIAL HEMORRHAGE
 Occurs in 20% to more than 40% of infants with birth weight
under 1500 gm,
 is less common among more mature infants.
 Intracranial hemorrhage may occur in the subdural,
subarachnoid, intraventricular or intracerebral regions.
 Subdural and subarachnoid hemorrhage follow head trauma
(e.g. in breech, difficult and prolonged labor and after forceps
delivery).
 Other forms of intracranial bleeding are associated with
immaturity and hypoxia.

49. Predisposing factors of IVH
 premature
 respiratory distress syndrome, apnea
 pneumothorax
 congestive heart failure
 presence of patent ductus arteriosus
 hypoxic ischemic or hypotensive injuries
 increased venous pressure
 hypervolemia, hypertensia

50. The structural and functional factors
of IVH in low-birth-weight infants
 poor structural support of germinal matrix vessels
 relatively large blood flow to deep cerebral
structure
 hypoxic-ischemic injury to germinal matrix or its
vessels

51. Clinical manifestation of IVH
 Absent Moro reflex
 Weakness, seizures, muscular twitching
 Poor muscle tone
 Hypotonia
 Lethargy
 excessive somnolence
 Pallor or cyanosis
 Respiratory distress
 Jaundice

52. Clinical manifestation IVH
 Bulging anterior fontanel
 Temperature instability
 Hypotonia
 Brain stem signs
(apnea, lost extraocular
movements,
facial weakness,
abnormal eye signs)

53. Laboratory correlates of blood
loss
 Metabolic acidosis
 Low hematocrit
 Hypoxemia, hypercarbia
 Respiratory acidosis
 Thrombocytopenia and prolongation of
prothrombin time (PT)

54. Diagnosis IVH
 History
 Clinical manifestation
 Transfontanel cranial ultrasonography
 Computed tomography
 Glucose level
 CBC - complete blood count
 Lumbar puncture

55. Outcomes and prognosis
 Patients with massive bleeding
have a poor prognosis.
 About 10-15% infants may develop
post hemorrhagic hydrocephalus
and chronic neurological pathology

56. Spinal cord
Spinal cord injuries are commonly caused by
strong traction when
the spine is hyper extended
forceful longitudinal traction on the trunk while
the head is still firmly engaged in the pelvic
shoulder dystocia

57. Clinical data
 Areflexia
 Loss of sensation
 Complete paralysis of voluntary motion
below the level of injury
 Epidural hemorrhage
 Apnea

58. 8
7
9
4
5
6
3
2
1
Roots
Trunks
Cords
Nerves
ANATOMY OF THE BRACHIAL PLEXUS
Ulnar
Median
Radial
7
8
9
5
Lateral
Posterior
Medial
4
6
Upper
Middle
Lower
1
2
3

59. Brachial Palsy
Risk Factors
 Shoulder dystocia
 Neonatal birthweight (macrosomia)
 Instrumental vaginal delivery
 Breech presentation
 Prior infant with brachial palsy

60. Erb Palsy –
Upper trunk plexopathy
 Injury to the 5th and 6th
cervical nerves (C5-C6 root
avulsion)
 Arm falls limply to the side of the body when
passively adducted
 Affected arm adduction & internal rotation
 Elbow extended & forearm pronated
 Wrist is flexed
 “Waiters tip” position
 Moro, biceps and radial
reflexes absent
 +/- Horner syndrome

61. Klumpke palsy
 Lower trunk (C8, T1) injury
 Poor grasp, proximal function preserved
 Absence of movements of the wrist
 Horner syndrome (ipsilateral ptosis and
miosis) if the thoracic spinal nerve is
involved
Flail arm
• Injury to entire plexus

62. Phrenic nerve palsy
 Injury to the C3,C4 or C5
 Brachial plexus injury
 RDS
 Paradox (upward) movement during
inspiration

63. Clavicular fracture
 Most common
 Crepitus, palpable bony irregularity
 Sternoclaidomastoid
muscle spasm
 Cry during movement of upper
extremities

64. Intraabdominal injures – target
organ
 Liver
 Spleen
 Adrenal gland (breech presentation)

65. Intraabdominal injures
 Sudden presentation
 Shock
 Abdominal distension
 Bluish discoloration, jaundice, pallor
 Poor feeding
 Thachypnea, tachycardia
 history: difficult delivery

66. Diagnosis.
 A thorough neurological examination
 Ultrasound examination of the brain
 EEG
 intracranial pressure measurement
 computed scanning
 are valuable.

67. Treatment
 The rapid responders from anoxia need observation in
the nursery for only 12 to 24 hours.
 These babies should be kept in ward, with a minimal
noise level or in the nursery.
 Acidosis, hypocalcaemia and hypoglycemia need
correction.
 Seizures should be controlled with phenobarbital

68. Treatment