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CPAPs for Premature Infants Report on: Continuous Positive Airway Pressure (CPAPs) For Premature infants Submitted By: Raheel Sayeed Id# 16355047 Submitted To: Prof.Paul Junor 1 | Page
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Page 1: Final Report_05july_2012docs

CPAPs for Premature Infants

Report on:

Continuous Positive Airway Pressure (CPAPs)

For Premature infants

Submitted By:

Raheel Sayeed

Id# 16355047

Submitted To:

Prof.Paul Junor

Dated:July05,2012

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Table Of Contents

1.1.Introduction 4

1.2.Aim of the project 4

2.1.Basic Physiology of respiratory system 6-8

3.1.Artificial ventilators 10-12

4.1.Effect Of CPAP 12-14

5.1.Types of CPAP 14-15

6.1.Methods and Material 15-21

7.1.1. Procedure 21-22

8.1.1.Other Ideas 23

8.1.Discussion 24

Conclusion 24

References

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Acknowledgement

Success of any project largely depends on the peoples associated with it. Their

support, guidance and their encouragement bring up confidence in you. In

this regard I really appreciate and thankful to all my colleagues and teachers

who made me self confident and motivated for this project. My special thanks

to Prof. Paul Junor who gives me tremendous support and help throughout

this project .Without his support and guidelines I am never be able to

withstand and take this opportunity to express my ideas in accordance with

the project. The assistance and hold up acknowledged from all the members

who have a say to this project, was imperative for the accomplishment of the

project. I am indebted for their continuous support and help.

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1.1.Introduction

CPAPs (continuous positive air way pressure) is a mechanical mean to deliver air pressure to

those patients who feels problem in normal breathing. It is a noninvasive technique which has

been use for the decades of years. This technique of providing artificial breathing gives them an

ease to support in their daily life. It may also enhance their life to be living healthy. An

effective ,cheap and easy way to maintain a normal healthy life. This is not the limit, beyond it,

this technique may also be involved in life saving activity for the premature infants as their

immature lungs, sometime, are not capable to breath their own due to their weak intercostals

muscles. for a while, this technique is use to increase the oxygen level in their blood by given

them oxygen support with the same principle with a different source. [6]So the CPAPs becomes

the multi diverse technique which not only helpful in adults but in preterm infants as well. It also

have some vital role in therapy of disorders like sleep apnea, respiratory distress

syndrome(RDS),dypnea and many more others.[3,4]

Since the gestation period the struggle for survival starts. It is the natures’ tendency to support

the one who struggles so as the theory of Darwin says “Survival of the fittest”. As soon the baby

is out of mother’s womb it starts it new journey of life. Many are lucky to be out by the normal

growth period but some aren’t; they face certain complications like chronic lung disease,

developmental delay, hearing impairment, intraventricular haemorrhage and respiratory distress

syndrome. These are some of the complication which is very high in neonates. As premature

have a smaller lungs their ability of breathing rate is much higher than adults. They need a

constant supply of air pressure depending on their gestation week / weight. To achieve this

constant air supply which can improve the mortality rate of the premature we can use

Ventilators, Continuous Positive Air Pressure’s and Bubble Continuous Positive Air Pressure’s. [1, 2]

1.2.Aim of the project

Basically this project is design to minimize the complexity and the cost of the CPAPs so that it

can be easily used in the developing countries like Ghana a state of Africa where the mortality

rate is on increasing in preterm infants mostly because of respiratory problems and immature

lungs. So there is a need of cheap machines which can easily be affordable and even can 4 | P a g e

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eliminate the cost of hospital expenses, power consumptions and its mode of operation is as

simple as on one touch it can be operated. Considering all these options, we in Latrobe

University trying to make such type of device which can be simple in use and should be easy in

operation. The machine should be powered by any natural resource or a source which doesn’t

require any consumable expenses. In this regard we are trying to make a respiratory control assit

device called CPAPs (continuous positive airway pressure) which will work on Solar Power

energy or any other renewable resource which can creates its own energy by applying any

technology.

1.2.1.Why use CPAPs

Continuous positive airway pressure (CPAPs) has been used in patients which have some

particular respiratory problems, this included sleep apnea in which there is some disorders in

breathing during sleeping which includes pause in breath for some seconds[28], sleep disorders

associated with heart failure, restrictive pulmonary diseases (decrease in total pulmonary

capacity)[29], severe stable chronic obstructive pulmonary disease, and the obesity-

hypoventilation syndrome in which overweight people cannot breath well and this will cause

decrease in oxygen concentration in blood with an increase of CO2 concentration[30].In this

regard, CPAPs has given dramatic change in significant physiological reimbursement, by

improving the worth of life, and even longer survival in some of the cases. CPAPs with a nasal

mask is therefore broad way to balance the increase folding of the air way.[7]

CPAPs giving a constant positive air pressure to the patient during natural breathing by

decreasing the work of breathing (WOB). It is use in cure of cardiovascular problems by treating

in various obstructive disease of sleeping disorders. It also can be use for associated pulmonary

disorders with congestive heart failures. Role of CPAPs in case of sleep apnea is really effective

and even in case of premature infants is an undeniable fact. Because the lungs of preterm babies

are very delicate and even it is quite different in shape as compare to an adult person.

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2.1.Basic Physiology of respiratory system

Lungs are the main respiratory organ of the respiratory system where all the main function of

respiration has to be done. From exchange of gases to diffusion of gases into and from the blood,

all process is taking place in this organ. Two main phenomenons which involve in the respiration

process are;

Inspiration

Expiration

In the process of inspiration ,atmospheric air is taking in through the nasal cavity from where it

will enters into the pharynx. The pharynx has two openings or it has the common opening for

food and air. The pharynx open into the larynx and esophagus, the air will enter into the larynx

because the esophagus is the path of food. The larynx then enters into a long tube like structure

called the trachea. The trachea and bronchi further divided into two bronchioles each of which

enters in the two sets of lungs. This whole process is an active phenomenon while in case of

expiration which is a passive procedure during a quiet breathing; the air which was taken in will

be exhale out and gives the gas in return called CO2.

Actually, the lungs are elastic in nature which can expand and contract during the entire process

of respiration and the muscle involved in this mechanism are abdominal muscles called rectus

abdominis, the intercostals muscles and the diaphragm. The rectus abdominal muscle provide

support in a force breathing, mostly after a physical exercise or after doing some hard work.

As lungs inflate and deflate the ribcage and abdomen increase and decreases. As volume and

pressure are related, altering the lung volume changes the air pressure in lungs.

Increasing lung volume lowers air pressure(pushes ribcages & abdomen Outwards)

Decreasing lung volume higher air pressure(pulling ribcages & abdomen Inwards)

Air flows from the region of higher concentration to the region of lower concentration, so air

flows into lungs when pressure decreases below atmospheric level and out when pressure

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increases above atmospheric level. During Inhalation contraction of external intercostals muscle

and diaphragm occurs and during Exhalation contraction of internal intercostals muscle occurs.

Fig:1

Source: http://www.google.com.au/imgres?q=physiology+of+respiratory

Considering the premature babies the lung and chest wall develop till 2-8 years of age. Below are

the comparisons of the adult as well as healthy infant’s facts of lung state.

1. Alveolisation continues beyond infant age.

20-50 million alveoli at birth in a healthy infant.

300 million by age 8 years.

2. Increase in alveoli tends to increase in alveoli surface area.

2.8 m2 at birth.

32m2 at 8 years of age.

75m2 at adulthood.

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3. Ventilation through the pores of Kohn & Lambert Canal is not well developed in early

years.

4. Lung matrix of the neonate contain small amount of collagen (elastin to collagen ratio

changes during the 1st month & years of life which affects lung stiffness as well as

potential for over distension & recoil.

5. Lung recoil (elastin) increases with age in children over 6 years of age.

6. Elastin recoil of an infant’s chest wall is close to zero & with age increases, because of

progressive ossification of the ribcage & intercostal muscle tone.

7. Orientation of ribs is horizontal in infants & later by 10 years of age, the arrangement is

downward.

8. Tongue is disproportionately large related to mouth.

9. Larynx is higher in neck(above Cervical4) [5,6]

2.1.2. Mechanism of Breathing

The mechanism of breathing involves the process of diffusion. The phenomenons of diffusion

define as; the movement of molecules from a region of higher concentration to a region of lower

concentration and this is actually happening in case of breathing mechanism. The O 2 is diffuses

into the blood when we breath in because the concentration of O2 is lower in the blood as in

alveoli so it will diffuse in the blood and the blood becomes oxygenated while the concentration

of CO2 is higher at the same time in blood then in alveoli so it will diffuse in alveoli. This whole

process is done by the breathing mechanism as we continuously taking in the fresh oxygen and

passively given out the carbon dioxide.

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Fig: 2

Source: http://www.google.com.au/imgres

In natural breathing, a pressure gradient is generated due to which the process of breathing

occurred. Figure 2 demonstrating a diagrammatic view of the breathing mechanism that when we

take air in, the volume of the lungs becomes increases which corresponds to the decrease of

pressure in thoracic cavity which in results contracts the diaphragm outwards and also the chest

becomes expended as demonstrated in Fig:2.Now due to low pressure inside the thoracic cavity

and high atmospheric pressure the passive phenomenon of expiration would be occur to maintain

the equilibrium condition and the diaphragm and chest would again be relax and the intra

thoracic pressure again increases and this cycle continues throughout the life.

2.1.3. Motor pathways

The diaphragm is the major muscle in the process of respiration which is creating the negative

pressure due to which, the process of inspiration would be taken place. It is a thin sheet of

muscle which will separate the thorax from the abdomen. Other muscles which are involve in the

respiration process are the internal and external intercostals muscles.[27]

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3.1. Artificial ventilators :

It consists of a mask, an oxygen source and an air bag. There is a valve to separates inhalation

and exhalation process. Air bag work as a manual pump for the continuous supply of oxygen. It

is use for the temporary purposes.

3.1.2. Ventilators :

They are usually design to work as human lungs or as an alternative of lung in case of

pulmonary disorders. Ventilators have different modes which can be run-in accordance with type

of disorder or according to the patient needs.

Two basic ventilations are:

Negative Pressure Ventilation: inspiration occurs because of negative pressure creates in

pleural cavity because there is low concentration of air inside the pleural cavity and high

concentration in the atmosphere. So –ve pressure ventilators are required.

Positive Pressure Ventilation: when the concentration is much higher inside the pleural cavity,

it will generate positive pressure in the pleural cavity so patient needs to expire.

Positive pressure ventilators are used in wide range of disorders. It is frequently use in

spontaneous mode where the patient required less effort to respire. While in case of compulsory

breaths, ventilators controlling all the parameters like tidal volume, respiration rates, etc.These

kind of breath are given to that patient who are unable to respire by their own efforts.

3.1.3.Types of Ventilator:

Two types of ventilator are:

Anesthetic Ventilator: It refers to use during operation or surgery when the patient is in

unconscious state.

Intensive Care Ventilator: In this air is delivering to the patient for inhalation. This type will

give the precise control for the respiration process.

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Terminologies Used In ventilation:

Fig:3

Source: http://www.google.com.breathing+mechanics+inspiration+and+expiration

3.1.4.Lung Compliance:

It is actually the ability of lungs and alveoli to expand on delivering a certain or required amount

of gas. It is usually in liter/cmH2O.It also refers to change in volume of the gas inside the lungs.

3.1.5.Airway Resistance:

It is resistance in flow of air during the entire process of respiration which will get increase in

bronchioles because of its smaller diameter.

3.1.6.Mean Airway Pressure:

It is basically the pressure of the air between aspiratory and expiratory phase.

Aspiratory Pause Time: This phase will occur when the alveolar pressure becomes equal to the

patient circuit. On that phase there is no flow of gas is taking place, so there is a time interval or

a pause state which is called as pause time.

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3.1.7.Tidal Volume: It is the total time inspired and expired during each breathing cycle. It can

be calculated by getting the product of flow rate and inhalation time.

Respiratory rate: Number of breath per second.

Assist control mode and SIMV mode: In these modes ventilator actually measures the breath

by taking an average of previous four breaths.

CMV: conventional mechanical ventilation is providing a forced ventilation to achieve normal

breathing. It determines the tidal volume at a respiratory frequency.

IMV: Time delay between each breath.

4.1.Effect of CPAP:

The CPAPs has been used to overcome the problems related with respiration process. It helps in

maintaining the oxygenation in blood and playing a vital role in decreasing the airway resistance

during the process of breathing mostly in premature infants. It also helps in increasing functional

residual capacity and has the tremendous effect on the immature lungs of preterm babies. CPAPs

maintain the air pressure in the lungs by giving a constant amount of pressure in accordance with

the required pressure. This is the beauty of this device that it has been designed as for the patient

needs. CPAPs therapy helps in maintaining the transpulmonary function of lungs by increasing

the functional residual capacity and thus by decreasing the bulk requirement of oxygen. It also

recover lung compliance

decrease airway resistance

lessen the work of breathing

enhance the ventilation-perfusion percentage.

4.1.2.Effect on Cardiovascular Stability:

High pressure of CPAPs can have a harmful effect on the cardiovascular system. The continuous

or high pressure of CPAPs results in compressing the heart vessels of right sides which in return,

will result in the decreased cardiac output due to which the amount of oxygen which is needed

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by the tissues of different organs is not sufficiently supplied. The major problem is with the

decrease cardiac output which will then subjected towards acidosis and causing the problem with

low blood pressure[14].In this case , the practice with the low pressure of CPAPs is highly

recommendable[15].However, sometime even the lower pressure becomes the cause for distress in

respiration and can cause some severe adverse effects. So it is quite necessary for the operator to

having a good familiarity with the level and standard pressure of CPAPs. In case of preterm

infants, one should have to be well known with limitations of their immature lungs otherwise it

may lead towards some severe degree of illness [14,17].

4.1.3.Effect of CPAP in Pulmonary Function:

Heart is the main pumping organ of the body through which the blood pumps throughout the

body. The heart will serves as a motor which plays an important role to maintain homeostasis of

the blood flow. When this pumping organ becomes unable to pump blood due to any disorder,

this will cause heart failure or congestive heart failure (CHF). Contrary of advancement in

medical sciences, this problem will remain the major cause of increasing mortality rate related

with the failure of heart. One of the major effect of CHF is because of lungs dysfunction in

which the fluidic concentration (lung edema) becomes increases which in turn will give rise to

muscles fatigue in performing routine exercises.[21]

One of the way to reduce or to control the pulmonary edema is by giving the relatives drugs or

by supplying forced Oxygen to patient in order to improve the performance of myocardial

muscles followed by the oxygenation. But sometime the crucial respiratory failure would be

occur and the only chance for survival will be the mechanical ventilation. The other way to get

avoided with these kind of disease in a very initial stage is by providing the CONTINOUS

POSITIVE AIRWAY PRESSURE which has been used from a long time to those

patients[13,17]..By applying a constant positive air pressure will help to sustain oxygen

concentration in the blood and helps to improves the lungs edema and the pulmonary function.

This will also cause to decrease in respiratory work and work of breathing by decreasing in left

ventricle preload and after load.[23,24]

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So the CPAPs may also be beneficial in use to increase the physical exercise capacity of the

patients having congestive heart failures. Constant use of CPAP for two weeks enhances the

stability of the pulmonary function with an increase stability of the regular exercise. CPAPs

therapy is helpful in maintaining the cardiac output in consideration with the treatment of CHF

patients it shows a favorable result which implies that CPAP may not only use for the cure of

disease with heart and lung but it may also increase the tolerance associated with the physical

exercise.

In a nutshell, it is quite clear that CPAP therapy not only enhances the cardiopulmonary

functions but it is equally helpful in increasing the capability of regular exercise.[23]

4.1.4.Effect On Central Nervous System

CPAPs therapy as in relation with their effects on nervous system reveals some adverse effects.

It may increase the intracranial pressure which may results to decrease in arterial pressure or the

blood pressure and this will cause to reduce the cerebral perfusion pressure. Intracranial pressure

is actually the pressure gradient of the brain tissues. In a supine position this pressure is 7 to 10

mmHg while in vertical position it becomes -10mmHg.As in case of CPAPs therapy the

intracranial pressure shows some variation with the type of CPAPs delivered i.e. in HeadBox

type it is showing a higher pressure rather in nasal prong or endotracheal one. It has been proved

that the high pressure of CPAPs influence the central venous pressure by increasing it and this

will cause an increase concentration of CO2 with a decrease level of O2 in blood, particularly

when it comes near to 8cmH2O.[31]

5.1.Types of CPAP :

5.1.2.Critical care ventilators.

This type of CPAPs have a high capacity to produce air flow as required by the patient. It may

really helpful for the cure of acute respiratory distress as compare to the portable CPAPs but the

problem with this type is its large size and complications in operation because even its

monitoring console is quite complicated as the basic aim of CPAPs is its ease of use, particularly 14 | P a g e

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in the noninvasive techniques. Moreover, the device is quite expensive as compare to portable

one and heavy in weight which may interfere in handling.[32]

5.1.3.Boussignac CPAP system

This type of CPAPs system consists of a valve which controls the pressure of air flow. It is

comprises of a plastic tube on-face mask valve which controls the air pressure, ranging from

2.5cmH2O to 10cmH2O.The valve itself control the flow without using any flow generator. The

valve consist of a plastic tube with a length of 5.5cm and the internal diameter is about

1.3cm.This valve is attached to a face mask which then attach to the patients nasal cavity and

mouth. The basic principle of this device works on the low pressure and high speed of oxygen

molecules which then transformed into the high pressure flow and thus maintain the required

pressure to be given. The device is user friendly and easy to use in operation, so it can be taken

in an emergency procedure.[32]

6.1.Methods and Material

The basic designing of this project is based on the following;

6.2.Power Source:

The power source is the basic part of this project because we have to use the source other then

the electrical; this means that whatever be the source it must have to be generating the power

itself. It must not be the conventional which usually powered our homes. In this regard we were

trying to use “Solar Power” in order to drive the rest of the circuit or may be some other

mechanical or chemical energy of source.

6.2.1.Solar Power:

Solar energy are the rays of sunlight which can be use to produce electrical energy by means of a

device called the solar cell. This form of energy can be converted into electrical form by using

photoelectric effect or photovoltaic effect. We can also concentrate this solar energy by using

convex lenses so the resulted beam of solar energy is denser and thus generate more power.

The two ways to create electric current and voltage is;

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Photovoltaic effect

Photoelectric effect

Sometime these two different processes will be considered as same but there is a slight

difference in their generation of voltage. In Photovoltaic effect, using a semiconductor material

which when placed in sunlight will direct emit the voltages. On the other hand, in photoelectric

effect, transfer of electrons would be occur from the valence band to the conduction band and

due to this change in energy level from higher to lower it will emits electron and thus the

generation of voltage between two electrodes will be occur.

Fig:4

Source:http://photovoltaics.sandia.gov/docs/PVFEffIntroduction.htm

6.2.2.How to build a solar module:

Actually we can have directly purchase a solar module according to our required output. But we

can also make a solar module by having assemblies of solar cells which are grouped together in

series can make a solar module. This array or solar module can convert the sunlight energy into

the electrical energy, as one solar cell can generate approx 0.5 mV of voltage so we can organize

it as our required output which is about 12V.

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6.3.DC Motor:

Fig:5

Source: http://gilbertojunqueira.com/quick-motor-tip-of-the-day#more-51

A 12V DC motor with a wing will produce air which will then be passed to the pressure sensor

through a small pipe commonly called as Neonates Cannula. The rotating speed of the motor is

directly proportional to the voltage supplied. So we can also control the pressure of the air by

controlling the rotational speed of the motor.[10]

6.4.1.Pressure Sensor

This is the most important part of the project or the key area for the required output. Pressure

sensor detects the current pressure of the air that is supplied from the fan through this we can

control the pressure according to a preset value or can be programmed in either way. After the

pressure is regulated, air is supplied to the tubing from which it will flow to the patient nostrils

through nasal cannula or a breathing mask.

6.4.2.MPX2010 Pressure Sensor( COMPENSATED PRESSURE SENSOR)

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In this regard we find the MPX2010 pressure sensor is the most appropriate and its output

voltage is directly proportional to the applied pressure. This pressure sensor will convert the air

pressure into the voltage and we can easily manage the required air pressure by checking the

output volts.[11]

Characteristics and features

0 to 10 kPa (0 to 1.45 psi)

FULL SCALE SPAN: 25 mV

Temperature Compensated over 0°C to + 85°C

Unique Silicon Shear Stress Strain Gauge

Ratiometric to Supply Voltage

Differential and Gauge Options

Fig:6

Source: http://www.google.com.au/imgres?q=MPX2010

Application Examples

In Respiratory Diagnostics Air Movement Control Controllers Pressure Switching

Pin Configuration:

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1 2 3 4

Ground +Vout Vs -Vout

Where Pin 1 is a notched pin.

Voltage Output V/s Applied Differential Pressure

The output voltage is increase with an increase in pressure side P1 in relation with pressure side

P2.likewise by raising the vacuum side P2 the voltage is also increases.

The other characteristics of the device is mentioned in the data sheet which is not necessary to

include in the report.[11]

6.5.1.Pressure ranges according to their Use:

Low Pressure

2-3 cmH2O

Maintenance of lung Volume in very low birth weight infants

During weaning

Medium Pressure

4-7 cmH2O

Increasing lung volume in surfactant deficiency

Stabilizing areas of Atelectasis

Stabilizing obstructive airway

High pressure

8-10 cmH2O

Preventing lungs Collapse with poor lung volume

Improving distribution of ventilation

Ultra High

11-14 cmH2O

Tracheal or bronchial collapse

In severe obstruction

Reestablishing lung volume during ECHO

Table:1

So there are specific pressure ranges of air for the specified problems in the infants according to

their difficulty need. These pressure are given to the patient according to the circumstances or in

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accordance with the degree of severances of disease.[12]

6.6.Flow Sensor:

Flow sensor serves as an emergency signal to alert for a problem condition in air pressure. It

monitors the air flow that is supplied to the patient, and outputs an emergency signal if the air

pressure is not in the desired range. This terminal can be a enhancement for the project if we get

the desired output.

Fig:7 Schematic circuit of flow detector

Source: http://www.google.com.au/imgres?q=air+flow+detector+circuit+diagram

The Figure 7 shows the circuit of air flow detector. This circuit can give a visual indication of the

rate of air flow. It can be also used to check whether there is air flow in a given space.

According to the circuit in figure 7, we can use a filament of the bulb which can sense the air

flow. When air is flowing through the filament the resistance will go on increasing because the

passing air creates heat resistance, and when the flow of air will be stop the resistance across the

resistor will be drop down because the air flowing will also removes the heat from the filament

and this variation of drop voltage can be detected by the opam (LM339) and we can generate

alarm or LED blinking as a signal in failure of air flow.

6.7.1.Nasal Prongs

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This device is consisting of plastic tube which will attach to the patient. It consist of two small

tube called the prongs which will place in the patients nostrils as shown in the figure 8.The other

tubular shape structured is connected to the air supply. Air flows from these prongs and the nasal

cannula is connected to the supplied air by the dc motor. The nasal cannula carries 1–5 liters of

air per minute or as desired.

The nasal prongs are a device used to deliver supplemental airflow to the person in need of

respiratory help. This device consists of a plastic tube which fits behind the ears, and a set of two

prongs which are placed in the nostrils.

Fig:8

Source: http://www.google.com.au/imgres?q=nasal+prongs

The figure 8 show the typical Nasal Prong which is used in CPAP system. But some time it is not

user friendly and some other kind of prongs are also be used.

6.8.Tubing:

The tubing used to deliver air is about 10mm in diameter with a very low resistance in flow of

air. This tubing is about 5 to 6 meter in length or depends on the circuit requirement.

7.1.1Procedure

Power will be given to the DC motor in order to create air flow which will then be passed to

nasal prong via tubing. There is a pressure sensor which control will monitor the pressure of the

air. This pressure sensor shows the pressure of the air flow in volts and through this sensors

output we will control the air flow by controlling the speed of the motor. Now this air is passing

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through the tubing supply to the patients nostrils via nasal prongs. A beaker with water with a

graduated glass tube is connected to the expiratory tube ,which comes from the patient

nostrils .The function of this expiratory tube is to control the air pressure. The graduation is

marked in cmH2O.T his metal tube allows gas to exhaust into the water, and pressure will

assorted by adjusting the depth of the tube in water.

The Flow sensor circuit is continuously monitoring the air flow to the patient and in case of

failure of air flow it gives an alarm to check out the problem.

8.1.1.Cost Evaluation

The total cost which is given by the university is about 400$.i.e 200$ for each student. The

approximate cost for this project if it is undertaken in the present circumstances is given below.

Component Price in AUD$

DC Motor ~16.00$

Solar Pannel ~40.00$

Rechargeable Battery ~ 25.00$

Tubing Giving by the hospital

Nasal Prongs Giving by the hospital

Flow Sensor ~34.00$

Air Detector Circuit ~12.00$

Other cost ~30.00$

Table:2

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8.1.2Other Ideas:

During this project I have went through some other interesting ideas which can make this project

simpler and easier in use but most of them are quite unprofessional and may kill the idea of

cheap cost. So I don’t discuss about those ideas. But one idea that clicks to my mind and is quite

good in my perspective is;

A simple way to charge the battery is by using a small dynamo, turned by the DC Fan

motor through a belt.

Fig:9

Source: http://www.google.com.au/imgres?q=Dc+motor+use+to+charge+the+12v+battery

The Figure 9 depicts one of my idea to generate the voltages through the same DC motor which

we will use to generate the air flow for the patient. In this, we can use two sets of DC motor and

by using a belt we can attach the axle of both the motors with each other. The one which will

take the power from the battery will generate the air flow and through this the axle of the other

motor will also be rotate creating the voltage on its input. Now this voltage can be use to charge

the same battery which is giving power to the first motor.

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CPAPs for Premature Infants

8.1.3.Discusssion:

The CPAP system which we want to design and implemented is a feasible project to design. But

it may take some more time and enhancements in its features and cost. Approximately the

research work has been done to implement the idea. In the report all the physiological and

technical parameter has been discussed. It is better to implement the idea in consideration with

the basic aim of this project which is the cost effectiveness and the simplicity. Because as we

know this is not a new invention but the same invention and basic principle with some new

advancement so that it can be use to lower down the mortality rate of premature infants in some

developing countries. One other aspect of this project is that it must be user friendly and the

operation of the system must be simple so that it can easily operated even at home without any

hesitation.

Conclusion

In a nutshell, the idea is ready to implement with some more advancement. The hardware is not

completed yet. This project is quite useful as it is power saving and regardless of expenses. The

natural resources are use to power the module and can easily be use in developing countries.

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