9) Maternal Medicine: Neurology Flashcards
Prevalence of epilepsy in pregnancy
0.5-1%
Percentage of WWE in reproductive age group
2/3
When can women be considered “no longer epileptic”?
If 10 years seizure free (5 of those off medication) or if childhood seizures but have reached adulthood without seizures or treatment.
Women with which type of seizures are highest risk for SUDEP
Tonic-clinic seizures
Rate of congenital malformations in WWE (including on AED)
Unmediated: 2.8% (comparable to background risk) Medicated: 4-10% risk - Levetiracetam 1-2% - Lamotrigine 2-5% (Dose dependent) - Carbemazepine 3.4% - Valproate 10% - Polypharmacy 17% 17% risk if previous child affected by AED congenital malformation.
Types of congenital malformations
Valproate - NTD, orofacial cleft, hypospadias, poor cognition and neurodevelopment (learning difficulties and autism)
Lamotrigine: Cardiac defects + clefts.
Levetiracetam: Cardiac defects + NTD
These have a lower risk of cognitive problems than SV.
Carbamazepine & Phenytoin - Cardiac/Cleft
Phenobarbital - Cardiac
When should folic acid be used?
5mg 3/12 pre-conception and at least until end of first trimester
What proportion of patients will remain seizure free throughout pregnancy?
67% seizure free.
As high as 74-92% if seizure free for 9-12m pre-conception.
Generalised seizures 74%, focal seizures 60%.
(17% will have improved control, 17% worsened control)
Risk of child having epilepsy
4-5% if one parent affected.
15-20% if both parents affected.
10% if previous child affected.
Advice re: AED dosing
Drug levels likely to fall in pregnancy (lamotrigine can fall by up to 70%). No role for routine level checking but need to consider clinical symptoms and likely increase dose in pregnancy.
Which infants should receive vitamin K?
Mothers on anti-epileptic drugs - 1mg vitamin K IM.
When should WWE be delivered?
No indication for early delivery.
Risk of seizure intrapartum
1-2% risk in labour
1-2% risk in first 24 hours postpartum
(Overall risk 3.5%)
What can be used prophylactically for women at high risk of seizures in labour?
Clobazam orally.
What percentage of pregnancies are complicated by status epileptics?
1%
Management of seizures in pregnancy/labour
If IV access: 4mg lorazepam or 5-10mg diazepam.
If no IV access: 10-20mg rectal diazepam, 10mg buccal midazolam.
If not resolving: 10-15mg/kg phenytoin.
If persistent uterine hypertonic - tocolytic.
If not resolved after 5 minutes then expedite delivery.
Risk of PND in WWE
29%
Contraception in WWE
If enzyme inducing drug (carbamazepine, phenytoin, topimarate, phenobarbitals, primidone) - either depot or coil (Mirena or copper).
If non-enzyme inducing drug then any method.
Lamotrigine levels are reduced by oestrogen containing contraceptives therefore avoid those or increase dose.
Emergency contraception - if enzyme inducer then copper coil or double dose LNG.
In what percentage of pregnancies are AEDs used?
1 in 200
What percentage of WWE will deliver a healthy baby?
96%
Risk of mortality in WWE compared to general population
10 x higher
60 per 100,000
When is fetal harm from AEDs highest?
1st trimester for congenital malformations. 3rd trimester for cognitive impairment.
Risk of SGA in WWE taking AEDs
2 x higher
Other risks of epilepsy in pregnancy
Miscarriage APH Hypertension IOL CS PTB PPH
Which are the first line AEDs in people with generalised epilepsy syndromes?
Lamotrigine and Levetiracetam
Breastfeeding in epilepsy
Yes!
What is SUDEP?
Death unrelated to trauma/drowning/status epileptics.
Main cause of death in WWE.
Incidence of SUDEP
On Lamotrigine: 2.5 per 1000 pt years
On other AEDs: 0.5-1 per 1000 pt years
In SCI, percentage of worsening spasticity?
12%
In SCI, treatment of spasticity
Intrathecal baclofen
Oral oxybutynin can be used for bladder spasms
What percentage of women with SCI conceive post injury?
14%
At what level of SCI is a ventilation assessment in pregnancy advised?
Above T4 (Vital capacity <12-15ml/kg requires mechanical ventilation)
At what level of SCI is there a risk of autonomic dysreflexia?
Above T6
At what level of SCI is there a risk of late PTL, altered perception of FM and inability to feel labour pains?
Above T10
What percentage of patients with SCI have PTL?
15%
At what level of SCI is there an increased risk of malpresentation?
Above T12
Above what level of SCI is there a risk of scarring in epidural space affecting analgesia?
Above L2-L4
What percentage of patients with SCI have their mobility limited further by pregnancy?
4.5%
What is the effect of SCI on congenital malformations and stillbirths?
Not increased
What is the recommended mode of delivery for patients with SCI?
Vaginal delivery unless concerns re: cephalopelvic disproportion.
- If SCI at young age or pelvic trauma then clinical pelvimetry recommended and likely CS.
Is admission recommended in patients with SCI?
Recommended late in 3rd trimester to avoid unattended delivery
What is the effect of SCI on VTE risk?
- First 6 months are SCI risk is increased, after this it reverts to normal.
- Score “1” on VTE for immobility in chronic SCI.
What happens in autonomic dysreflexia?
Any noxious stimuli below level of lesion isn’t modulated by the brain and so sympathetic system goes crazy!
Hypertension –> Vagal stimulation –> Bradycardia
Life threatening.
Symptoms of autonomic dysreflexia
Nausea, anxiety, malaise, prickling sensation in skull, ringing in head, throbbing headache.
Treatment of autonomic dysreflexia
Removal of noxious stimuli.
Medical treatment: SL nifedipine, GTN patch/spray, Nitroglycerine ointment, Labetalol/Hydralazine.
Who needs an epidural in SCI?
Should be recommended early in labour for people with lesion above T6 to prevent AD.
Can be used as an option for analgesia for others.
What level is sensory supply from uterus?
L1-T11
What level is cervical dilatation perceived at?
T11/T12
Rules for suprapubic catheter and CS
Change catheter in 24 hours prior to surgery
Incision 2cm above suprapubic catheter
Use non-absorbable sutures
Breastfeeding in SCI
Yes! Initiation may be delayed if SCI above T4 (may require visual stimulation or oxytocin nasal spray)
Risks of spinal cord injury occurring during pregnancy
Increased rates of miscarriage and congenital anomalies (secondary to hypoxia from spinal shock).
Direct trauma to uterus from compression can cause injury.
MS is more common in men or women?
2-3 x more common in women
Mean age of onset of MS
30 years