Estimating with confidence

It should be remembered that deaths from pre-eclampsia nearly equal those from eclampsia29: it is not the convulsions that make this condition so dangerous. Eclampsia is conventionally considered to be the end stage ofthe disorder, but this is an oversimplification. Some patients have only minor systemic disturbances and the problem is easy to control with rapid recovery after delivery. Other patients are desperately ill with progressive renal failure, disseminated intravascular coagulation, microangiopathic haemolysis, and liver dysfunction. Thus convulsions are a marker for severe illness but not a reliable one. Some patients with pre-eclampsia are more dangerously ill than others with eclampsia. Often too much effort is spent in giving treatment to pre-eclamptic women to prevent convulsions (in circumstances where eclampsia is unlikely) and too little in determining the extent and severity of the illness, so that those with severe systemic disturbances can be selected for urgent delivery. In addition many doctors do not appreciate the chameleonlike nature of this extraordinary condition. The fulminating illness may begin with headaches and vomiting that can easily but dangerously be discounted as "viral gastroenteritis." Jaundice is a rare presentation30 and is often misinterpreted by specialists. The severity (and therefore dangers) of a preeclamptic illness are never reliably shown by a single measurement. It is conventional to equate the degree of hypertension with the extent ofthe problem. Although this is true in general, there are enough exceptions to make this a dangerous assumption. There is increasing evidence for "normotensive" pre-eclampsia,3' a condition characterised by intrauterine growth retardation and maternal problems that may include disturbances of clotting and hepatic function.32-34 Some rules of thumb are helpful for those trying to cope with this disease in the frontline. Firstly, no consultation with a pregnant woman is complete without a blood pressure measurement and a check for proteinuria. Those with blood pressures of 140/90 mm Hg or more and proteinuria of 1+ or more on dipstick examination should be considered to have advanced disease and admitted to hospital on the same day. Those who are also feeling ill need to be admitted by flying squad. Any pregnant woman suffering from headaches and vomiting in the second half of pregnancy should be assumed to have terminal pre-eclampsia until proved otherwise. In hospital specialist assessment of any case of suspected pre-eclampsia is incomplete without knowing a patient's renal function (measurements of plasma urea and creatinine are good enough), platelet count, and hepatic function (plasma aspartate aminotransferase activity). These investigations need to be constantly available, and all but the last are already provided by most emergency laboratory services. As pre-eclampsia is an unstable condition that may change dramatically regular reassessments are essential. Cure depends on elective delivery. It is time that doctors took a new look at this major problem of obstetric care. All cases of eclampsia occurring in Britain should be reviewed regularly to provide an analysis and overview of what is happening. With their well established tradition of audit, all obstetricians would surely want to assist such an endeavour, which should lead to better prevention and management.