Plasma potassium in acute severe asthma before and after treatment.

The plasma potassium level was studied in 15 patients with acute severe asthma before and six to 14 hours (mean = seven) after treatment with a nebulised beta 2-agonist, salbutamol, intravenous aminophylline and hydrocortisone in recommended doses. The mean basal plasma potassium level in the untreated acute severe asthmatics was 3.54 mmol/l (range 2.6-4), which is on the lower side of normal (3.5-5.0). There was a significant decrease in the mean plasma potassium level to 2.9 mmol/l (2.6-3.5) in asthmatics who received the above treatment. The clinical implications and association of these findings with fatal asthma are discussed.