Pregnancy and Lesions of the Nervous System

Neurological Emergencies in PregnancyNormal pregnancy, although associated with considerable metabolic and endocrine changes, is usually well tolerated by a healthy nervous system.However, if fortuitous neurological disorders arise, they are made more difficult to manage not only because of the presence of the feetus but be- cause the increased plasma volume, relative reduc- tion of serum electrolytes and large output of oestrogens affect both the electrical stability of the brain and the behaviour of pathological lesions.Abnormal pregnancy complicated by toxaemia, hypertension, and malnutrition may also result in damage to the nervous system.Cerebrovascular accidents, including subarachnoid heemorrhage, may complicate normal or abnormal pregnancy.These will be discussed first and compared with acute encephalitis, which may be a difficult differential diagnosis.Seizure states, exacerbations of demyelinating and allergic disorders, benign raised intracranial tension and unusual presentations of tumours are some other disorders that may arise acutely.Subarachnoid htemorrhagein pregnancy differs in etiology from subarachnoid hlmorrhage in the general population, because it occurs in a younger age group.McKissock & Paine (1959), in a large survey of subarachnoid hlemorrhage, showed that in females the mean age of incidence was 53, whereas for males the mean age was 50.This age distribution supported the generally held view that the incidence of subarachnoid htemorrhage in pregnancy is no different from that in the nonpregnant, as the mean age of incidence was