Clinical factors predicting a rapid response to short-acting beta2 agonists in mild and moderate asthma exacerbations.
BACKGROUND
The need for establishing criteria that facilitate decision-making has lead to search for factors that could predict prognosis and response to treatment for asthma exacerbations.


OBJECTIVE
To assess which clinical factors are associated with a rapid response to short-acting beta2 agonists during asthma exacerbations.


METHODS
Two hundred and twenty consecutive adults with mild to moderate asthma crisis were included. Their medical history and physical examinations were completed and closely monitored: heart rate, respiratory rate, SO2, and FEV-1. They were initially treated with O2 and micronebulized albuterol (2.5 mg every 20' x 4). A FEV-1 > or = 80% of predicted and an improvement at 90' were considered as good response.


RESULTS
One hundred and forty-four (65.5%) patients had a good response to micronebulized albuterol, while 76 (34.5%) required steroids and hospitalization. Early relapse rate (72 hours) in this study was low (3.4%) and it was associated to other factors, such as: upper airway infection (40%) and history of oral steroids usage in the previous year (80%). The variables associated to a good response were: < 6 hours since crisis started, no hospitalization or steroid use during a crisis in the last year, initial SO2 > or = 90% and initial FEV-1 > or = 60%.


CONCLUSIONS
These variables are easily measured and predict a therapeutic response in asthma patients when first seen in the emergency room.
Clinical Epidemiology Medical Research Unit. Torreón National Medical Center, Mexican Institute of Social Security, Torreón, Coahuila, México. veromart@internetual.com.mx
Verónica A
VA
Martínez Ordaz
Juan A
JA
Benítez González
Cuauhtémoc B
CB
Rincón Castañeda
Armando
A
Nieves Rentería
Miguel A Madero
MA
Fernández del Castillo
Víctor M
VM
Velasco Rodríguez
D000293:Adolescent; D000318:Adrenergic beta-Agonists / Q000627:therapeutic use*; D000328:Adult; D000420:Albuterol / Q000627:therapeutic use*; D001249:Asthma / Q000150:complications / Q000188:drug therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D013997:Time Factors
D000318:Adrenergic beta-Agonists; D000420:Albuterol