Revision - Birth Injuries & Congenital Infections Flashcards
What is the periosteum?
A layer of dense connective tissue that lines the outside of the skull and does not cross the sutures (see diagram).
What is caput succedaneum?
A diffuse collection of fluid on the scalp OUTSIDE the periosteum.
Does cross suture lines.
Prognosis of caput succedaneum?
Does not require treatment - resolves in a few days.
Cause of caput succedaneum?
Pressure on presenting part during delivery e.g. prolonged delivery, ventouse delivery.
What is a cephalohaematoma?
Subperiosteal haemorrhage which is bound by the periosteum –> does NOT cross suture lines.
Collects between the skull & periosteum.
Cause of a cephalohaematoma?
Caused by damage to the blood vessels during a traumatic, prolonged or instrumental delivery.
What is the most common site affected in cephalohaematoma?
Parietal region
What may develop as a complication of cephalohaematoma?
Anaemia & jaundice
Monitor bilirubin
How long does a cephalohaematoma last?
can last up to 3m
When does a cephalohaematoma present after delivery?
24-48h
What may occur to a cephalohaematoma in its resolution phase?
Calcification
What are the 2 key differentials for a cephalhaematoma?
1) Caput succedaneum
2) Subgaleal haemorrhage
What is a subgaleal haemorrhage?
This occurs between the aponeurosis of the scalp and periosteum and form a large, fluctuant collection which crosses sutures lines.
Why can subgaleal haemorrhages be life-threatening?
May cause life-threatening blood loss:
- pallor
- tachycardia
- hypotension
- shock
What is a craniosynostosis?
One or more of the fibrous sutures in an infant skull PREMATURELY FUSES, changing the growth pattern of the skull.
This can result in raised ICP and damage to intracranial structures.
Surgical intervention often required.
What is facial nerve paralysis during delivery often caused by?
Forceps delivery
What nerve roots are implicated in Erb’s palsy?
C5, C6 and occasionally C7 (upper brachial plexus injury)
Injury mechanism in Erbs palsy?
Traction injury due to excessive lateral neck flexion towards the contralateral side, or excessive shoulder depression, resulting in violent stretching +/- tearing of the upper portion of the brachial plexus
What nerves are injured in Erbs palsy?
(4)
1) Musculocutaneous nerve
2) Axillary nerve
3) Suprascapular nerve
4) Nerve to subclavius
Clinical features of Erbs palsy?
1) Loss of sensation over “sergeant’s patch”, lateral arm and lateral forearm.
2) Wasting of deltoid, supraspinatus and infraspinatus muscles and the anterior compartment of the arm.
3) Loss of shoulder abduction and external rotation, elbow flexion, finger extension and wrist supination.
Describe appearance of affected arm in Erb’s palsy
“Waiters tip” appearance:
- Limp, adducted, internally rotated shoulder
- Extended elbow
- Flexed wrist facing backwards (pronated)
- Lack of movement in the affected arm
Where is sensation affected in Erbs palsy?
1) “sergeant’s patch”
2) lateral arm
3) lateral forearm
What movements are affected in Erbs palsy?
1) shoulder abduction
2) shoulder external rotation
3) elbow flexion
4) wrist supination
Management of Erb’s palsy?
Function normally returns spontaneously within a few months. If function does not return then they may required neurosurgical input.
What nerve roots are injured in Klumpke’s palsy?
C8/T1 (lower brachial plexus injury)
What is the mechanism of injury in Klumpke’s palsy?
Traction injury due to excessive force placed on an abducted shoulder results in violent stretching +/- tearing of the lower portion of the brachial plexus.
What 2 nerves are injured in Klumpke’s palsy?
Median & ulnar
What sensation is affected in Klumpke’s palsy?
1) median and ulnar distributions of the hand
2) medial forearm and arm
Motor effects of Klumpke’s palsy?
1) All small intrinsic muscles of the hand. affected –> there is generalised wasting of hand muscles with a loss of MCPJ flexion, IPJ extension, finger abduction and adduction, and opposition.
2) Loss of wrist flexion –> ‘claw hand’ deformity, wrist is classically held supinated.
What nerve root is implicated in Horner’s syndrome?
T1
What is plagiocephaly?
Deformational, or positional, plagiocephaly is when a baby develops a flat spot on one side of the head or the whole back of the head.
It happens when a baby sleeps in the same position most of the time or because of problems with the neck muscles that result in a head-turning preference.
What is the main complication of a fractured clavicle at birth?
Injury to the brachial plexus with a subsequent nerve palsy.
What can severe cases of VZV infection in pregnant women lead to?
Pneumonitis, encephalitis & hepatitis
What are the management steps in a case where a pregnant woman has encountered a person infectious with VZV?
1) Ask if mother has had previous 1ary VZV infection:
If yes –> assume immunity (no further action).
If no –> go to 2)
2) VZV IgG testing required to confirm immunity status.
3) If not immune and <20 weeks gestation –> woman should receive varicella zoster immunoglobulin (VZIG) within 10 days of the contact, and before the onset of rash.
4) If not immune and >20 weeks gestation –> woman can receive either VZIG, or alternatively Aciclovir can be given from days 7 to 14 following exposure.
What are the 2 potential foetal complications of maternal VZV infection?
1) varicella of the newborn
2) foetal varicella syndrome
What is the key risk factor for varicella of the newborn?
If maternal chickenpox occurs within the last 4 weeks of the pregnancy.
Management of varicella of the newborn?
VZIG +/- aciclovir
What is foetal varicella syndrome caused by?
Subsequent reactivation of the virus in utero as herpes zoster.
This reactivation ONLY occurs when the fetus is infected by maternal varicella before 20 weeks gestation.
If a mother with suspected contact with infectious VZV person is found not to have immunity and is <20 weeks gestation, how soon should IV varicella immunoglobulins be given?
Within 10d of exposure
What are 5 key maternal infections that can have foetal complications?
1) VZV
2) Rubella
3) Zika
4) CMV
5) Toxoplasmosis
What is the most common virus transmitted to the fetus during pregnancy?
CMV
Risk of damage to foetus is low though.
In what trimsester is the risk of CMV related damage to the fetus highest?
1st trimester
Clinical features of congenital CMV?
1) Intrauterine growth restriction
2) Hepatosplenomegaly
3) Thrombocytopaenic purpura
4) Jaundice
5) Microencephaly
6) Chorioretinitis
Investigation of choice in suspected toxoplasmosis?
Serology
Impact of toxoplasmosis infection in HIV/immunosuppressed patients?
Cerebral toxoplasmosis accounts for around 50% of cerebral lesions in patients with HIV:
Constitutional symptoms, headache, confusion, drowsiness.
When is the risk of congenital toxoplasmosis higher in pregnancy?
The risk is higher LATER in pregnancy
What triad of features is seen in congenital toxoplasmosis?
1) Intracranial calcification
2) Chorioretinitis
3) Hydrocephalus
When is sudden infant death syndrome (SIDS) most common?
3m of age
What is the main risk factor for SIDS?
Prematurity (4x)
