Obstructive Lung Disease

still controversial points. However, there were some topics that should have some coincidences, such as the optimal peak expiratory flow (PEF) used when deciding a patient's discharge from the emergency room (ER). It was amazing to realize that the percent predicted PEF value recommended to decide discharge from the ER varied from 50 to 75% (Argentinean 60%, British 75%, Canadian 50%, American 70%). There was no mention of acute asthma management in the Australian report.' For a patient with a predicted PEF of 600 L/min, the Canadian physicians would discharge at a PEF of 300 L/min and the British doctors would not discharge until 450 L/min. In this way, the hospitals in Great Britain would be crowded by asthmatics that could be treated at the ambulatory setting. On the other hand, asthmatics from Canada were at a higher risk of relapse. Which PEF is the best PEF for deciding discharge? There is some evidence, although weak in nature, that supports the 60% of predicted PEF as the best value. In a review of management of acute life-threatening asthma,6 an FEV, of at least 60% of predicted has been suggested as the cutoff point between discharge and admission. In another study,7 the patients without relapse had been discharged with an FEVy of 1,879 mL +110 (SE); that was about 60% of the predicted FEVI. Finally, it appears that a 60% of predicted PEF value was the more reasonable PEF if the correlation between FEV, and PEF was accepted.8 We further need to test prospectively the guidelines to ensure that we are going in the right direction.