What is Eclampsia & how does it differ from Pre Eclampsia?
WHAT IS ECLAMPSIA?
Eclampsia is a Greek word meaning ‘bolt from the blue’ or 'lightening'. It describes one or more convulsions occurring during or immediately after pregnancy as a complication of pre-eclampsia. Eclampsia has been recognised since ancient times, but it wasn’t until the mid-nineteenth century that doctors began to realise that the fits were normally preceded by a collection of circulatory disturbances now known as pre-eclampsia.
Confusingly, however, very few cases of pre-eclampsia culminate in eclampsia, while eclampsia can sometimes precede pre-eclampsia.
Eclampsia is rare, affecting about 400 women per year in the UK.
WHAT ARE THE SIGNS AND SYMPTOMS?
Eclamptic convulsions look no different from epileptic fits. The mother is gripped by synchronised, repetitive, jerky and sometimes quite violent movements involving muscle groups in the eyes, jaw, neck and limbs.
The spasms lead to temporary loss of consciousness, stop the mother from breathing, may make her bite her tongue and sometimes cause urinary incontinence.
Most convulsions last for a minute or less before stopping spontaneously. If they are continuous, without a break, the woman is said to be status eclampticus, which is extremely dangerous.
Before they suffer an eclamptic convulsion, most women have signs of pre-eclampsia, most notably high blood pressure and/or protein in the urine. Often there are one or more warning symptoms - such as restlessness, shakiness, intense headache, upper abdominal pain or visual disturbances - before the fit occurs, although these are very common, non-specific symptoms which are usually perfectly benign.
For some sufferers, however, eclampsia is entirely unheralded, and signs of pre-eclampsia appear afterwards.
WHEN DOES IT OCCUR?
Eclampsia can occur at any stage during the second half of pregnancy - and some, very rare, cases have been reported before 20 weeks. At the other extreme, the fits can occur as late as during labour or after delivery.
Again very rarely, it has been reported up to 2 weeks post delivery.
WHAT IS THE CAUSE?
Several factors are probably involved, including: reduced blood flow to the brain, caused by a combination of small clots and spasm of the small arteries; swelling in the brain (cerebral oedema), possibly as a complication of excessive fluid retention; bleeding from small arteries ruptured by the intensity of the blood pressure.
WHAT ARE THE DANGERS?
Any woman with eclampsia is at risk of suffocation while the seizure is happening. Afterwards she may still be at risk, depending on the degree of brain trauma that triggered the fit, and the severity of the underlying pre-eclampsia.
Most women make a full recovery from eclampsia, but one in every 50 sufferers die and some are left with a permanent disability.
Unborn babies whose mothers are affected by eclampsia are at risk of acute asphyxia (suffocation). About one in every 14 of these babies die. It is now known that eclampsia occurring antenatally - particularly pre-term - tends to be more severe for both mothers and babies than eclampsia occurring during labour or after delivery.
WHAT IS THE TREATMENT?
Until recently it was assumed that anticonvulsants, such as diazepam and phenytoin,for example, were the best agents for controlling eclampsia and preventing further convulsions.
But a huge trial - known as the MAGPIE trial - has now demonstrated that magnesium sulphate - the drug of choice in the US for many years - is better than either at preventing further convulsions, and may also save more lives. The drug is thought to work by improving blood flow to the brain, which suggests that impaired cerebral blood flow is the main cause of eclampsia.
When these results were published in the summer of 1995, only 2-3 per cent of UK obstetricians were known to use magnesium sulphate, but is now common place. The drug is given by injection and is relatively straightforward to use. An initial 'bolus' is generally given followed by a slow infusion with very strict fluid balance protocols maintained.
Many women experience initial side effects to the bolus such as feeling very hot or as though they are passing urine. While unpleasant these side effects are usually short lived (subside within minutes) and the benefits outweigh the risks.
However, there is no suggestion that magnesium sulphate has any effect on the underlying pre-eclamptic disorder, and a woman who recovers from eclampsia may still be at risk from other complications of the condition.
There is evidence to suggest that magnesium sulphate may prevent eclamptic convulsions in women with pre-eclampsia, but as yet it is not possible to identify exactly who would benefit most from treatment.
CAN IT BE PREVENTED?
In theory eclampsia can be prevented by vigilant antenatal care, including a well-timed delivery. But in practice fits which occur without warning may be impossible to prevent. In the US, magnesium is routinely given to women with pre-eclampsia in the expectation that it prevents progression to eclampsia. This regime is increaasingly currently standard practice in the UK.
WHAT HAPPENS IN THE NEXT PREGNANCY?
Because eclampsia is so rare its recurrence rate is not known.
About one sufferer in 20 will get pre-eclampsia in the next pregnancy, with the individual risk higher for those who suffered eclampsia relatively early in the pregnancy and lower for those who had a fit at or near term.
Treatment with low-dose aspirin may be recommended in cases where the problem arose before 32 weeks but for for optimum safety, any woman who has suffered eclampsia in one pregnancy should be considered ‘at-risk’ in the next pregnancy. Former sufferers may like to consider preconception counselling with an expert to devise an appropriate antenatal care programme for the next pregnancy. This might include a Thrombophilia Screen.
UNDER NO CIRCUMSTANCE SHOULD SELF-MEDICATION BE CONSIDERED. ALWAYS DISCUSS WITH YOUR GP / CLINICIAN PRIOR TO TAKING MEDICINES.
SUFFERED AN ECLAMPTIC FIT? YOU HAVE DRIVING RESPONSIBILITIES.
The Driver and Vehicle Licensing Agency give the following advice:
“Anyone who experiences a seizure during delivery or pregnancy should stop driving and notify DVLA as soon as possible.
It is their legal responsibility to notify DVLA. Having done so each case will be looked at to see if there remains a continuing liability to fits. Many in this situation are regarded as having had provoked seizures and allowed to retain their licence.”
YOUR INSURANCE MAY BE INVALID IF YOUR RESPONSIBILITY IS NEGLECTED.
Every Woman is entitled to understand what happened in her pregnancy when pre eclampsia strikes. I hope to be able to support that process.