30 September ~ 6 Oktober 2012 (Week 9)

Title of  Activity 

-Discussing with the supervisor regarding the presentation slides 

-Preparing the presentation slides in order to be ready to presented 

Objective

-The quality of the and the material need to be presented 

Content / Procedure

-Search on the internet for information

-Capture the concept of the slides that need to be presented 

-Discussing with the supervisor about the contain of the presentation

-Copy the slides from the slide that i have been made

 Presentation Slides 

Result & Analysis

-These slides are what i'm going to present to the assessors , what in the slides are just a keyword so it needs to be explained well  in the time of the presentation .

-In the slide got introduction and problem statement as well as literature review , methodology and project progress , conclusion .

-Block diagram will explain about every part's function of this project .

   

23 ~ 29 September 2012 (Week 8)

Title Of Activity

Project briefing - Presentation

 Student were briefed on the preparation before and during the presentation conducted. 

16 ~ 22 September 2012 (Week 7)
(Research)

Title of  Activity

-Project Research - How to calculate the heart rate from ppg .

Objective

-To know how to calculate the heart rate from ppg .

-Make it as literature review .

Content / Procedure 

surf the internet for some information about how to calculate the heart rate

Calculate the heart rate 

      We mainly used the maximum gradient to detect the peak

point of the SpO2 signal that was

similar to the R–R interval

in the ECG signals, as shown in Fig. 1. The fi rst derivative

was calculated at each point of the SpO2 by the equation:

Y(n) = X(n + 1) − X(n) .

If the gradient was larger than 60, we marked the X(n)

point. We then found the local initial climbing point. From

this point, we took the forward and backward 30 points as

a domain, and then found the maximum and minimum

points. Then, the PPGA is the amplitude between adjacent

peak points and foot points (Fig. 2). The HBI is the time

interval betweenadjacent peak points (Fig. 2), and is similar

to the R–R interval in ECG signals, so the heart rate is easily

obtained from this P–P interval.

Fig. 1. Definition of peak-to-peak signals. a From the plethysmograph
(PPG) signal. b From the electrocardiograph (ECG) signal

Fig. 2. Definition of the plethysmograph amplitude (PPGA) and the
heart-beat interval (HBI)

RESULT/ ANALYSIS

-Get the way how to calculate heart rate from ppg .

9 ~ 15 September 2012 (Week 6)

Title of  Activity

-Second briefing for final year project 1 

-Discussing about the methodology and block diagram .

Objective

-To be briefed about the final year project 1 and the details of the content 

-To know about the methodology of this project 

Content - Procedure

-All student had to know about the presentation and the proposal as well as the submition date of both .

-Get the information about the methodology .

Methodology

              in this project ppg is a sensor placed on a thin part of the patient's body, usually a fingertip. Light of two different wavelengths is passed through the patient to a photodetector. The changing absorbance at each of the wavelengths is measured, allowing determination of the absorbances due to the pulsing arterial blood alone, excluding venous blood, skin, bone, muscle, fat, and in most cases nail polish .With this sensor it is possible to measure both oxygenated and deoxygenated hemoglobin on a peripheral scale .

  

This project is aimed to design and construct an interfacing circuit for data acquisition using a commercial pulse oximeter sensor.  The oximeter sensor which comprises of a red LED, an infra red LED and a photo-detector is to detect the pulse volume change to monitor the change in blood vessel re-activity  And also required to design the driver circuitry. utilize a NI DAQ card and to program using Labview for circuit control, data acquisition and data saving for future data processing .

Result & Analysis

-Get he knowledge about the methodology of this project . 

 

 

2 ~ 8 September 2012 (Week 5)
(Research)

Title of  Activity

Project Research- pulse oximetry 

Objectives 

-To know what is pulse oximetry and its relationship with ppg .

-make it as literature review .

Content Procedure 

surf the internet for information 

 Pulse Oximetry 

      

      Pulse oximetry is a non-invasive method allowing the monitoring of the saturation of a patient's hemoglobin.

A sensor is placed on a thin part of the patient's body, usually a fingertip or earlobe, or in the case of an infant, across a foot. Light of two different wavelengths is passed through the patient to a photo detector  The changing absorbance at each of the wavelengths is measured, allowing determination of the absorbances due to the pulsing arterial blood alone, excluding venous blood, skin, bone, muscle, fat, and (in most cases) nail polish. With NIRS it is possible to measure both oxygenated and deoxygenated hemoglobin on a peripheral scale (possible on both brain and muscle).

Reflectance pulse oximetry may be used as an alternative to transmissive pulse oximetery described above. This method does not require a thin section of the patient's body and is therefore well suited to more universal application such as the feet, forehead and chest, but it also has some limitations. Vasodilation and pooling of venous blood in the head due to compromised venous return to the heart, as occurs with congenital cyanotic heart disease patients, or in patients in the Trendelenburg position, can cause a combination of arterial and venous pulsations in the forehead region and lead to spurious SpO2 (Saturation of peripheral oxygen) results.

Pulse oximeter and its relationship with ppg 

           A pulse oximeter is useful in any setting where a patient's oxygenation is unstable, including   intensive care, operating, recovery, emergency and hospital ward settings, pilots in unpressurized aircraft, for assessment of any patient's oxygenation, and determining the effectiveness of or need for supplemental oxygen. Assessing a patient's need for oxygen is the most essential element to life; no human life thrives in the absence of oxygen (cellular or gross). Although a pulse oximeter is used to monitor oxygenation, it cannot determine the metabolism of oxygen, or the amount of oxygen being used by a patient.

 For this purpose, it is necessary to also measure carbon dioxide (CO2) levels. It is possible that it can also be used to detect abnormalities in ventilation. However, the use of a pulse oximeter to detect hypoventilation is impaired with the use of supplemental oxygen, as it is only when patients breathe room air that abnormalities in respiratory function can be detected reliably with its use. Therefore, the routine administration of supplemental oxygen may be unwarranted if the patient is able to maintain adequate oxygenation in room air, since it can result in hypoventilation going undetected.

Result &Analysis 

-Got the knowledge about the pulse oximetry .

 

26 August ~ 1 September 2012 (Week 4)
(Research)

Tittle of activity

- Design procedure of ppg .

Objectives 

-To know what is the design procedure ?

Content / Procedure

Search from internet


1.infrared emitter

               Infrared was chosen as the light source because infrared is well absorbed by blood and very weakly absorbed by other tissues and fluids in the body.  This means that the blood volume changes can be very easily observed.  The iron content in the blood reflects the infrared waves.  During systole, the heart pumps blood through the body.  This causes the volume of blood in the tissue to increase [by sara sieg and bill ziebold project 38. ppg).  This results in more absorption of the infrared light.  During diastole, the heart muscle relaxes and fills with blood.  This results in a lower volume of blood in the tissues.  When there is less blood in the tissues, there is less absorption of the transmitted signal.  Therefore, the output of the photoplethysmograph should emulate the waveform shown in Figure 1 :

The frequency of the pulse rate is dependent on other physiological factors.  When the body is at a higher temperature, or there are increased amounts of physical activity or stress, the pulse rate increases.  Also, the amount of blood pumped through the body per minute increases.  This will result in a stronger output signal on the photoplethysmograph.  The contrary is also true.  If the tissue being measured is elevated above the heart or is very cold, the blood flow will be significantly decreased.  This will result in a marked decrease in the output waveform of the photoplethysmograph.

2.Infrared Receiver



An infrared receiver was chosen to be matched to the infrared emitter.  This was done to ensure that the receiver would be able to detect the signal from the emitter.  The matched infrared receiver was
also chosen to minimize the amount of ambient light that would be detected.  Any detected ambient light would interfere with the output of the photoplethysmograph and appear as noise.  This would make it hard to differentiate the output signal from the changes in blood volume.  It is also beneficial to use an infrared emitter because changes in blood oxygen content are very prominent in the visible light region.  Restricting the light that is detected will minimize any measurement of oxygen changes in the blood.  The receiver was placed so that the light from the emitter was transmitted, as opposed to reflected, through the skin and tissues.  This was done to prevent any interference from the emitter.  When the receiver is placed next to the emitter on the same surface, the receiver may pick up some of the emitted signal before it travels through the body as well as the reflected signal.  This leads to a very confusing and inaccurate waveform.  Also, the signal to wave ratio of a reflection mode photoplethysmograph is much lower than the transmission mode photoplethysmograph [by sara sieg and bill ziebold project 38. ppg].  This occurs because more of  the signal is transmitted than reflected.


3.Device Placement
The placement of the emitter and receiver on the body is also an important aspect of the photoplethysmograph.  The areas chosen were the earlobe and the area between the thumb and the index finger.  They were chosen because of the consistency of the tissues and also because it would be relatively easy to hold the emitter and receiver in place.  These areas on the body can also be held relatively still to reduce motion artifact which would distort the output signal.  Another area of interest was the tip of the index finger.  This area was rejected because of the presence of bone that would reflect a higher proportion of the wave.  This would significantly reduce the strength of the signal that could be received.  To make measurements on this part of the body, it would be necessary to use a receiver in reflection mode.  Another part of the body considered was the nasal septum.  This area of the body is often used in the clinical setting.  The nasal septum is ideal because even if the body goes into shock, there will still be blood flow to the nasal septum.  When the body goes into shock, blood flow is significantly reduced to the extremities.  However, during shock, blood still flows to the brain and other major organs including the nasal septum [The placement of the emitter and receiver on the body is also an important aspect of the photoplethysmograph.  The areas chosen were the earlobe and the area between the thumb and the index finger.  They were chosen because of the consistency of the tissues and also because it would be relatively easy to hold the emitter and receiver in place.  These areas on the body can also be held relatively still to reduce motion artifact which would distort the output signal.  Another area of interest was the tip of the index finger.  This area was rejected because of the presence of bone that would reflect a higher proportion of the wave.  This would significantly reduce the strength of the signal that could be received.  To make measurements on this part of the body, it would be necessary to use a receiver in reflection mode.  Another part of the body considered was the nasal septum.

Result/Procedure 

got the knowledge of the design procedure .

19 ~ 25 August 2012 (Week 3)

(Research) 

Title of  Activity

-Project research -photoplethysmography (ppg)

Objective

-To know what is ppg ?
-Make it as a literature review.

Content /procedure

search about information from internet 

photoplethysmography (ppg)

        

                The photoplethysmograph is a sensor that uses an emitter-receiver pair to determine blood flow.  A light emitting diode is used to transmit light through the skin.  The receiver picks up the transmitted signal, which is then analyzed with signal processing techniques.  The pulse wave is produced by the changes in blood volume in the arteries and capillaries.  Changes in blood volume produce changes in the optical absorption of the transmitted signal.  

                 The light transmitted through the tissue can be highly scattered or absorbed depending on the tissue.  The detector, which is positioned on the surface of the skin, can detect the reflection or transmission of waves from various depths and from highly absorbing or weakly absorbing tissues .  Regardless of the absorbency of the tissues and skin, it is assumed that the amount of light absorbed and/or reflected by these tissues will remain constant .

Result & Analysis

- Got some knowledge about ppg . 

                                                              

12 ~ 18 August 2012 (Week 2)

TITTLE OF CONTENT 

As for the second week it was for searching for ideas and titles but for me i had came late so my supervisor have already given me the tittle and i was satisfied by her choice .

Objective 

- Supervisor was trying to describe about the project and trying to convince me to take that tittle as i came late and had to tittle . 

Content 

-To do some research about the project and try to get some information .

-To do some research through internet ,and books and some magazine and previous final year project to collect more information.

- This is the first discussion between me and my supervisor here is a pic of what we have discussed.

Result & Analysis

To get the main idea of the project that have been provided by my supervisor and try to build up the block diagram and flow chart and know what is the objective and benefits .

5 ~ 11 August 2012 (Week 1)

As for the first week, everyone had to choose his own supervisor and try to create a blog and update everything related to the project progress and to be checked by the supervisor .however , blog is used to update what's ever been done weekly .