Assessment of Emergency Spacers Versus Traditional Spacers for Delivery of Aerosolized Drugs

* The goal of this clinical trial is to evaluate the performance, feasibility, and safety of emergency spacers compared to traditional spacers for the delivery of aerosolized drugs using pMDI. in young children and adult asthmatic patients The main questions it aims to answer are: 1. Measuring total emitted dose emitted from pMDI alone and attached to spacers. 2. Determining the pharmacokinetic parameter of aerosol delivered by different spacers. 3. Determining the lung bioavailability of aerosol delivered by different spacers. 4. Determining the systemic bioavailability of aerosol delivered by different spacers. 5. Determining the lung function after aerosol delivered by different spacers. 6. Determining the safety Researchers will compare salbutamol amount delivered using pMDI alone and pMDI connected to differents spacers to evaluate the performance, feasibility, and safety of emergency spacers compared to traditional spacers for the delivery of aerosolized drugs. Participants will asked to * inhale salbutamol through pMDI alone and pMDI connected to different spacers * perform lung function test using spirometer * urine samples will be taken from patients 30 minutes and 24 hours after dose inhalation. * use pulse oximeter to measure heart rate