1. MEDICAL DISSECTION LAB ED5060 Roshan S(ED11B052) Saneeth S(ED11B053) Chaitanya Kumar D(ED11B045) NEBULIZER

2. ABSTRACT The objective of the experiment was to dissect a nebulizer in order to identify its components and to uderstand its functioning. INTRODUCTION A Nebulizer is a drug delivery device used to administer medication in the form of a mist inhaled into the lungs.Nebulizers are commonly used for the treatment of cystic fibrosis, asthma, COPD and other respiratory diseases. Nebulizers are of two types :- 1.Jet(Pneumatic) small volume nebulizer 2.Ultrasonic nebulizer Jet nebulizers are based on the venturi principle, whereas ultrasonic nebulizers use the converse piezoelectric effect to convert alternating current to high-frequency acoustic energy. Important variables for both types of nebulizer are treatment time required, particle size produced, and aerosol drug output. Ultrasonic nebulizers generally have a higher output rate than jet nebulizers, but a larger average particle size. Ultrasonic nebulizers can also substantially increase reservoir solution temperature, the opposite of jet nebulizer cooling.[1] TOOLS REQUIRED Screwdrivers,Hands EXPERIMENTAL PROCEDURE The outer case of the Nebulizer was first removed. Then the wire assembly consisting of the fuse was removed. 3. Fig.1 The inlet/outlet is then removed using hands. Fig.2 Finally the transformer-cum-motor unit is removed. 4. Fig.3 DISCUSSION Design Concept The Nebulizer dissected was a Jet Nebulizer.The design of the nebulizer is a straightforward one - Air from the atmosphere is taken in through the inlet(Fig.2). The air is then passed on to a compressor which compresses the air and pushes it out through the outlet(Fig.2). The input voltage is passed through a transformer. The output of the transformer is then fed to the motor which helps in the compression of the air. The compressed air flows at high velocity through a liquid medicine and turns it into an aerosol. This aerosol is taken in by the patient and eventually reaches the lungs. Product Modules The nebulizer basically consists of two modules - 1.Power supply module 2.Air compressor module Geometric layout 5. Functional Decomposition Product Architecture 6. Salient Features * The device has a constant flow rate. There is no means whatsoever to control the speed of the compressor. * A unique feature of this device is that the secondary coil of the transformer acts as the coil of the motor. This helps to reduce transmission losses and also helps reduce space and cost. History The first "powered" or pressurized inhaler was invented in France by Sales-Girons in 1858. This device used pressure to atomize the liquid medication. The pump handle is operated like a bicycle pump. When the pump is pulled up, it draws liquid from the reservoir, and upon the force of the user's hand, the liquid is pressurized through an atomizer, to be sprayed out for inhalation near the user's mouth. In 1864, the first steam-driven nebulizer was invented in Germany. This inhaler, known as "Siegles steam spray inhaler", used the Venturi principle to atomize liquid medication, and this was the very beginning of nebulizer therapy. The importance of droplet size was not yet understood, so the efficacy of this first device was unfortunately mediocre for many of the medical compounds. The Siegle steam spray inhaler consisted of a spirit burner, which boiled water in the reservoir into steam that could then flow across the top and into a tube suspended in the pharmaceutical solution. The passage of steam drew the medicine into the vapor, and the patient inhaled this vapor through a mouthpiece made of glass. The first electrical nebulizer was invented in the 1930s and called a Pneumostat. With this device, a medical liquid (typically adrenalin chloride, used as a bronchial muscle relaxant to reverse contriction) was made aerosol by the power from an electrical compressor. As an alternative to the expensive electrical nebulizer, many people in the 1930s continued to use 7. the much more simple and cheap hand-driven nebulizer, known as the Parke-Davis Glaseptic.In 1964, a new type of electronic nebulizer was introduced: the "ultrasonic wave nebulizer". Today the nebulizing technology is not only used for medical purposes. Ultrasonic wave nebulizers are also used in humidifiers, to spray out water aerosols to moisten dry air in buildings.[1] Improvements Possible 1. Option to control the flow rate can be provided. 2. Fan serves no particular purpose. It can be avoided. 3.Provisions can be made to reduce the noise produced. Using sound absorbing material in the interior could help. 4.In recent years, several nebulizer designs have become available to decrease the amount of aerosol lost during the expiratory phase.These include reservoir bags to collect aerosol during the expiratory phase, the use of a vented design to increase the nebulizer output during the inspiratory phase (breath-enhanced nebulizers), and nebulizers that only generate aerosol during the inspiratory phase (breath-actuated nebulizers). Because these designs improve drug delivery to the patient, they have the potential to reduce treatment time, which should improve patient compliance with nebulizer therapy[3] SUMMARY A Jet nebulizer was dissected to understand its design and identify its components.The functioning of the nebulizer and its role in treatment of patients with lung-related diseases was learnt. REFERENCES 1.en.wikipedia.org/wiki/Nebulizer 2.http://www.ncbi.nlm.nih.gov/pubmed/12425742 3.http://bolsonenterprises.webs.com/documents/Nebulizers%20-%20Principles% 20and%20Performance.pdf