Page 185 - Livre électronique des RFTP 2023

P124.PARADOXICAL BRONCHOSPASM: AN UNCOMMON

ADVERSE EFFECT OF SALBUTAMOL ADMINISTRATION

KH. MAHMOUDI1, A. SAYHI1,2, Y.ABDELHEDI1, F. GUEZGUEZ1,2, I. GHANNOUCHI1,2,
S. ROUATBI1,2

1: LABORATORY OF PHYSIOLOGY AND FUNCTIONAL EXPLORATIONS, FARHAT HACHED HOSPITAL,
SOUSSE 2: RESEARCHLABORATORY, LR12SP09

INTRODUCTION : Paradoxical bronchospasm is a condition where
bronchoconstriction occurs rapidly and unexpectedly after using a
sympathomimetic bronchodilator. This creates a paradox as it contradicts the
expected bronchodilation response. Here, we report a rare case of paradoxical
bronchospasm in a patient with asthma following the use of salbutamol.

CASE REPORT : A 57-year-old man with a smoking history of 42 pack-years was
diagnosed with asthma based solely on clinical data, 2 years ago. No other past
medical history was recorded. The patient was treated with a long-acting beta-
agonist and salbutamol on demand. He has recently experienced worsening
symptoms, including dry coughing episodes over the past two months. He was
referred to the laboratory of Physiology and functional explorations for pulmonary
function testing. Spirometry with a bronchodilation test was conducted according
to recent international guidelines. Baseline spirometry showed a mild proximal
obstructive ventilator defect, as evidenced by z-scores of the FEV1/FVC ratio and
the FEV1 of ""-1.93"" and ""-2.36”, respectively. The bronchodilator test using 400 µg
of salbutamol was performed and showed reductions in FEV1 and FVC of 210 ml (-
11% from baseline, -8% compared to predicted value) and 370 ml (-13% from
baseline, -10% compared to predicted value), respectively. Paradoxical
bronchospasm was thus suspected based on the patient’s clinical manifestations
and the results of the bronchodilatation test.

DISCUSSION : Paradoxical bronchoconstriction is a rare adverse event associated
with bronchodilator therapy. Possible hypotheses include improper inhaler
technique leading to airflow turbulence, immunoglobulin E-mediated reaction to
inhaler excipients, and irritation from propellants, preservatives, or solution
characteristics, particularly in β2-agonist metered-dose inhalers. However, the
exact mechanism is unknown and further investigation is needed.

CONCLUSION : It is important for both patients and healthcare providers to be
aware and vigilant about the potential complications of paradoxical bronchospasm,
despite its relatively low prevalence. A thorough investigation of each case is crucial
to ensure accurate diagnosis and appropriate management.

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