Hyperventilation of pregnancy presenting with flaccid quadriparesis due to hypokalaemia secondary to respiratory alkalosis.

Hyperventilation in pregnancy is a cause of chronic respiratory alkalosis. Alkalosis either metabolic or respiratory may cause intracellular shift of potassium ions that may lead to hypokalaemia. However, the resultant hypokalaemia in respiratory alkalosis is usually mild and does not cause much clinical features. A five-months-pregnant female of the age 25 years presented with sudden onset flaccid weakness of both lower limbs associated with thigh muscle pain followed by weakness of both upper limbs within three days. Subsequent investigation revealed severe hypokalaemia due to acute exacerbation of chronic respiratory alkalosis secondary to hyperventilation of pregnancy, other causes of hypokalaemia being ruled out. Respiratory alkalosis causes tetany and other clinical manifestations. But hypokalaemia and such weakness is rarely found. Thisis probably the first report of this type from India.