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Eucapneic hyperventilation of cold air (EHCA) provokes bronchospasm in asthmatics. Although inhaled cromolyn powder and sympathomimetic solutions have attenuated the bronchospasm induced by EHCA, comparison of both drugs in solution has not been performed. We performed a prospective double-blind study comparing cromolyn solution, metaproterenol solution, and placebo (normal saline) given prior to EHCA. Eight asthmatics defined by a 20% reduction in forced expiratory volume in 1s (FEV1) after EHCA consented to the study. Patients were tested on 3 separate occasions at a similar time of day. Each session began with a determination of FEV1 followed by a randomized double-blind treatment. A repeat FEV1 (pre-EHCA) was performed 20 min after drug inhalation. Twelve minutes of EHCA was performed consisting of 4 min of tidal breathing, 4 min of eucapneic hyperventilation (60-70% of the predicted MVV) and a final 4 min of tidal breathing. FEV1 was performed immediately, 5 min, and 10 min after EHCA. The lowest value was defined as the post-EHCA FEV1. The pre-EHCA FEV1 was significantly larger after metaproterenol pretreatment compared to the pre-EHCA FEV1 following cromolyn (p = 0.01) and saline (p = 0.04). Metaproterenol pretreatment had a significant protective effect in comparison to placebo pretreatment (p less than 0.01). No other paired comparisons (cromolyn vs. placebo, cromolyn vs. metaproterenol) achieved statistical significance at a 0.05 level. In conclusion, metaproterenol is superior to cromolyn in protecting against cold-air-induced bronchospasm.
R H Israel, and
J M Kohan, and
R H Poe, and
M C Kallay, and
D W Greenblatt, and
S Rathbun
May 1968,
Annals of allergy,
R H Israel, and
J M Kohan, and
R H Poe, and
M C Kallay, and
D W Greenblatt, and
S Rathbun
February 1992,
Archives of disease in childhood,
R H Israel, and
J M Kohan, and
R H Poe, and
M C Kallay, and
D W Greenblatt, and
S Rathbun
August 1987,
Annals of allergy,
R H Israel, and
J M Kohan, and
R H Poe, and
M C Kallay, and
D W Greenblatt, and
S Rathbun
April 1969,
Annals of allergy,
R H Israel, and
J M Kohan, and
R H Poe, and
M C Kallay, and
D W Greenblatt, and
S Rathbun
April 1989,
Annals of allergy,
R H Israel, and
J M Kohan, and
R H Poe, and
M C Kallay, and
D W Greenblatt, and
S Rathbun
July 1986,
Journal of applied physiology (Bethesda, Md. : 1985),
R H Israel, and
J M Kohan, and
R H Poe, and
M C Kallay, and
D W Greenblatt, and
S Rathbun
December 1994,
American journal of respiratory and critical care medicine,
R H Israel, and
J M Kohan, and
R H Poe, and
M C Kallay, and
D W Greenblatt, and
S Rathbun
November 1975,
Pediatrics,
R H Israel, and
J M Kohan, and
R H Poe, and
M C Kallay, and
D W Greenblatt, and
S Rathbun
January 1996,
Prehospital and disaster medicine,
R H Israel, and
J M Kohan, and
R H Poe, and
M C Kallay, and
D W Greenblatt, and
S Rathbun
August 1978,
Journal of applied physiology: respiratory, environmental and exercise physiology,
