34th DaY of AttAchMent

I found out more information of the equipment and computer that we collected from the eye clinic. It is a research that is done by a doctor from that clinic. I only able to find out more when the doctor is back. The programs that is being used to program this software are C++, visual basics and Matlab. There will be templates of images installed using matlab and will be shown on the television with high resolution. There will be a camera placed on a stand that the subject will placed their head on it. The amazing part is the camera is directly vertically above and mirror is being placed at 45 degree from tha face. It applies the same theory of telescope and camera would take the reflected image.

A contractor came down to the workplace to do a survey on the common atmospheric frequency for wireless in the hospital. He is using a interface card and an antenna-like machine to detect the frequency. There will be waveforms generated and in FFT cycles (square waves or spiky waveform). The theory used is from TP and BSPA which are what i learnt from school. If two frequencies exist, the stronger frequency will suspress the weaker frequency so notch filter will then need to be used to remove the noise. For example, singapore and malaysia used to have same atmospheric frequency so sometimes singaporeans will have malaysia channels. This shows that two places have common frequency, there will be more interference. This applies to our local broadcast radio.

After that, i did a little repair and delivered equipments. I misplaced some rods and feeling guilty. I have learnt my lesson which is doing one thing at a time and quality matters more than the quantity. I shall bear this in mind that i shall always do things systematic so i will not confused myself.

33rd DaY of AtTaChMenT

In the morning............
Went to clinic C which is the eye clinic to collect a desktop and a mitsubishi monitor that the doctors did not use it before. Therefore, we are bringing it to our workplace and figuring how to use the software that is in the system. I shall try to understand the usage of it while reading the manual and operating it.

Troubleshooting the infusion pump STC-508 after charging it overnight to make sure there is really no problem. I have learnt something or can i say i found out by accident? After i finished with the occlusion test, i switched the pump off and on again but careless of me forgot to restart the occlusion test before switching it on. Restarting the occlusion test which means releasing the pressure that accumulated at the end of tubing connected to the infusion device analyzer. i believe that the error 4 is indicated as the self-check of the device concluded that the occlusion detection circuit is defective due to the accumlated pressure for this case. I am not sure whether what i have said is right but it is what i learn from my own. May be i should try to ask Mr Sin tomorrow for better understanding.

In the Afternoon..................
I took 2 Intermitten Suction Unit (ISU) from the "Awaiting Repair" cabinet. The same problem that lies with both of them is there is no vacuum during suction. The first thing that came to our mind is try to clean the internal parts of the devices as we suspected there is a blockage somewhere so by cleaning will remove the dirt from blocking the delivery of vacuum. After doing that, the problem still exist. While we inspecting the device, we found out there is a thick layer of dirt stuck at the external filter that prevents vacuum from flowing and the gauge is faulty as the arrow unable to point to -120 mmHg that we set so we replaced it. One device solved another one to go. We did the same for the other ISU. However, some unknown problems appearing. The gauge is unable to reach the desired pressure that we set when it is on for the intermitten mode. We try to change the parts one by one to see where the problem is. I was out of my wits so i asked Lee Chong so he asked me to try adjusting the flow control valve. After spending an hour or more, i still unable to solve the problem. Therefore i have to stop and try it again as there is a foul smell from the aspirator that i used. May be it is an indication that i should do something else and try it again tomorrow.

32nD DaY of AtTaChMenT

Wow, month of April is ending in a few days' time and most of the preventive maintenance are done. There still a few more devices for preventive maintenance but they are not located in the hospital. instead, they are in woodland polyclinic so Lee Chong went there to do preventive maintenance while i chose to stay in the workshop to do more of repair as i want to learn more in depth for repair.

I took a mattress pump control to fix the problem which is one of the tubes on the connector broke off. Before gluing back the tube, Lee Chong told me that i have to check for the strength of air flow by putting your fingers on the opening of the tube and a hissing sound will be heard. If the sound is very soft, the pump required to be changed as the air pressure decreasing ( pump exceeding the lifespan). Therefore, i changed the pump and charged it on the work order to have a record of what i used from the storeroom. He told me that the stepper motor will turn until a point that two openings are closed and no air will be blown out. However, the motor will still continue turning and release air at one opening. This is one of the method how alternating airflow works in mattress pump. Another method is one of the opening will close slowly while opening the other slowly.

After lunch, Faz gave me 4 devices for simple repair. They are mercury manual sphygnomamometer, single flowmeter, transport flowmeter and opthalmoscope. Firstly, the fault for mercury manual sphygnomamometer is a small amount of mercury is stuck in the middle so i keep pumping and releasing the air from the cuff in order for the amount of mercury to flow down. It took me about 15 minutes to solve it. Secondly, the inner glass (O2 meter) of single flowmeter crack. The store have a smaller meter instead of the one i need to replace with so i change the knob and casing. It is funny as i could just change the whole thing instead of fixing the separate parts together. However, i have to use back the O2 probe as it costs 2 times the price of the flowmeter. Thirdly, the fault lies with the transport flowmeter is the glass cover for the gauge, which measure the amount of oxygen in the tank, is missing so i have to change the whole gauge for them. Lastly, the opthalmoscope unable to light up despite charging for a long time. When i switch it on, it is really unable to light up so i have to check whether the battery is faulty. Therefore, I charged it overnight to make sure it lies with the battery.

31st DaY of AtTaChMeNt

Continued from where i stopped yesterday by doing checking for transport physiologic monitor from welch allyn ( propaq and propaq encore).
These are the things that i have done:

• plug in the SpO2 probe to make sure it is in working condition by checking the infra red sensor and test it on my finger
• Testing the monitor's ability of producing the desired waveform that i chose in the patient stimulator.
• Using the non-invasive blood pressure monitor tester to check the accuracy of the monitor in terms of systolic, diastolic and mean in mmHg.

After that, i double check on the autovent3000 (resuscitators) and found out there is one of them was unable to deliver the correct amount of air to the gas flow analyzer. It shows signs of leaking around the patient valve so i went to Mr Sin for guidance and the cause of the leaking is due to the diaphragm not placing properly and dirt stuck on the one way valve that causing it to open. After Mr Sin placing the diaphragm properly, the resuscitator seems to be working fine. This is the most common problem. Check valve has the same property as the one way valve in the patient valve and it has a stick-like thing that forces the valve to open to allow air which flowing at the direction that the stick is facing to flow in while forcing it to close when air is flowing at the opposite direction.

Thankfully, i am able to complete the checking before having my lunch as AH staff will be collecting it in the afternoon.

Checking the ventilators from SAF by comparing the tidal volume and breath rate from the tester with the desired values that you set for the volume delivered and frequency in bpm. Tidal volume in litres is volume delivered divided by frequency.

In the Afternoon..............................

I did the preventive maintenance of the automatic blood pressure monitor with some guidance from Lee Chong.

The tests that we carried out:

• overpressure test
• pressure check
• simulation test
• pressure leakage test

The first two tests, i have to wrap the cuff on a bottle that it able to withstand the pressure and used a 3 way connector to connect the monitor with the cuff and NIBP monitor tester. Usually, we only do the first three tests. For pressure check, we will check whether the pressure generated by the monitor is able to go up to the desired value that is stated in the tester. Secondly, for the simulation test, we have to compare the readings that we get from the monitor for systolic, diastolic and mean with the standard values in the tester. The accuracy must be with in the range of +/- 10% of the value.

Lastly, quoted the LCD display module for the PCA pump. Met up with some problem as the part number for it is totally different in singapore compared to uk so Mr Ong had to fax us the diagrams and part number of the components. Mr Ong said that we have to buy the whole assembly which is the whole circuit board that is equalvient in buying the whole device. Luckily, they have the module that i wanted and save a lot of money too.

30th DaY of AttaChMent

I had to complete the checking of devices such as transport physiologic monitor and resuscitators by tomorrow afternoon as There is JP morgan marathon that is sponsored by alexandra hospital. The marathon is a charity drive. Since Alexandra hospital is covering the cost of the marathon, portable devices are loaned for wednesday. I just have to do the functioning check and the accuracy of resuscitators, Autovent3000. I took quite some time figuring out the connection of the device. For example, i swapped the connection of tubings of the source gas inlets with the patient valve outlets. After looking through the user manual, i know more about the connection of the device. It is purely a pneumatic unit. I used a flow analyzer to check the tidal volume delivered and the frequency in terms of bpm. The resuscitator considered accurate if the readings is +/- 10 % of the standard value. Sometimes, the readings will be like out of range by 50. I asked Mr Sin and he said it is pretty alright as it is just slightly off. Thankfully, i got to finish all 4 resuscitators by today. I going to start on the checking of the monitor ( welch Ally's propaq) and hopefully i am able to finish all of the devices before collection.

Remember the manikin that i spent a lot of time doing it? Mr Sin tried to repair it and he told me what went wrong. My soldering skills still have rooms for improvement. The skillreporter unable to turn on the manikin due to my poor skill of soldering. I shall make good use of my attachment in Alexandra Hospital to improve my soldering skills. Soldering in school is totally different with working environment in a way.