Setting the reference range of the provocholine cough test by the Astograph method

JRCT ID: jRCT1041220103

Registered date:13/12/2022

Basic Information

• Recruitment status: Recruiting
• Health condition(s) or Problem(s) studied: cough variant asthma
• Date of first enrollment: 13/12/2022
• Target sample size: 120
• Study type: Interventional

Intervention(s)

Bronchial smooth muscle contraction by inhalation of provocholine

Dissolve probocholine in physiological saline and prepare two-fold serial dilutions of 0.049, 0.098, 0.195, 0.391, 0.781, 1.563, 3.125, 6.25, 12.5, and 25 mg/ml. While measuring the respiratory resistance (Rrs) by the 3 Hz oscillation method using Astograph Jupiter 21, inhale the probocholine solution of the above concentration continuously for 1 minute each from the lowest concentration. The inhalation load was stopped immediately when Rrs increased to twice the initial value.

Outcome(s)

• Primary Outcome: Total cough count for 30 minutes induced by inhalation of provocholine
• Secondary Outcome: Nothing

Key inclusion & exclusion criteria

• Age minimum: >= 20age old
• Age maximum: Not applicable
• Gender: Both

Include criteria

Men and women over 20 years old
Adults with no history or symptoms of respiratory illness
After sufficient informed consent to participate in this study, the patient's free will to give written consent.

Exclude criteria

Those with hyperthyroidism
Those with cardiovascular disease with bradycardia
Those with peptic ulcer disease
Those with Addison's disease
Those with gastrointestinal or urinary tract obstruction
Those with epilepsy
Those with parkinsonism
Those with vagal hypervagus
Those with myasthenia gravis who regularly take cholinesterase inhibitors
Those with moderate airflow limitation (%FEV1 <70% or FEV1 <1.5 L)
Those who are pregnant or breastfeeding
Those who have a fever of 37 degrees or higher
Those who have been infected with the new coronavirus within the last month
Those who are judged to be inappropriate by the principal investigator or co-investigator

Related Information

• Primary Sponsor: Johsuke Hara