HYPOVOLÆMIA IN STATUS ASTHMATICUS

A significant, though variable, hæmoconcentration was observed during eleven episodes of status asthmaticus in nine patients with bronchial asthma, aged 18-43. Mean blood-volume was 55.9 ml. per kg. as compared with 63.3 ml. per kg. in healthy persons matched for age, sex, and weight. Blood-volume was also diminished when compared with the patient's own values measured for the asthma-free interval, the hæmatocrit during the attack being increased by 7% and the serum-proteins by 0.6 g. per 100 ml. During or immediately after relief of the airway obstruction pulse-rate rose and bloodpressure fell accompanied by clinical signs of collapse in four patients. Central venous pressure was below 0 cm. water in this phase in all five patients for whom it was recorded. Rapid parenteral volume replacement in five patients led to immediate circulatory improvement. A possible relation of hypovolæmia with the unexplained death of asthmatic patients is suggested.