Automation and its advantages

I have learnt quite alot about automation through this attachment process. By experiencing automation first hand, i have a deeper understanding on automation and its uses, which we have learnt in chapter 1 of LMQA.

In the lab, several tests are performed using an automated method. This includes Full Blood Count (FBC) test and coagulation test. The samples for FBC are run using either the Advia, Sysmex or LH FBC analyser while the coagulation samples are run using the Sysmex CA-1500 machine. One clear advantage is that by using automated means, the samples are run at a faster rate. For example, if PT/APTT test for coagulation is performed manually, alot of time is required as one staff can only handle one sample at a time. In contrast, several samples can be placed in the machine and run at any one time, although the test will still be carried out one by one. Furthermore, manual method may bring about inconsistency as a person may only notice the clot a few seconds after it happens.

In the routine haematology lab i'm attached to, staining of slides are also performed automatically using the HemaTek stainer. If staining is done manually, it will take 6 mins for the staining process alone and a further 3-5 mins for the slides to dry. On the other hand the approximate rate of staining using the HemaTek stainer is 1 slide/ min. One will only need to place the slide on a conveyor-like space and the slides will be automtically stained, rinsed and dried.


HemaTek Stainer


Some people may think that human resource is needed much less with the use of automated machine. However, this is not necessarily true. Machine only does test and produces result for us. It is not able to analyse and troubleshoot. For example, the Advia FBC analyser will only alert technologists by producing (*)s on the result worksheet. The technologist's job is to identify the fault and correct it. For example when starting up the analyser, if the control did not fall within the given range, the technologist have to figure out what is wrong (e.g: check if the reagent is expired).

Steps to follow when the result worksheet is printed:
1) Make sure that the MCHC is less than 37 and more than 32, HCT is about 3 times more than Hb, difference between MCHC and CHCM is within 2. If not, repeat test.
2) check for panic range :
- Platelet less than 20 or more than 800 x10(9)/L
- WBC less than 1 or more than 50 x10(9)/L
- Hb is less than 5 or more than 22 g /dL for females or 20 g/dL for males.
If there are any panic ranges, call the wards to inform the doctor of the patient's platelet/wbc/Hb levels.
3)If the platelet level is below 140 x10(9)/L, check blood sample for presence of blood clot. If there is a blood clot, reject the sample and request for a repeat.

Overview of tests done in urinalysis lab

(a) Dipstick – 2 types
1) five-patch test strip to determine quantity of pH, protein, glucose, ketone bodies and blood in urine.
2) 10-patch test strip for glucose, bilirubin, ketone, specific gravity, blood, pH, protein, urobilinogen, nitrite and leukocytes in urine.

The dipstick test is performed routinely. However, it is only done if the sample is that of an outpatient or patient with renal disease. Usually, only the 1st dipstick consisting of 5 tests is used. The 10-patch test stip is used only if the specific tests, such as bilirubin and urobilinogen, are requested.

(b) Microscopic analysis (using KOVA glasstic 10 with grid slide)
This is used to determine or identify cells that may be found in urine samples.9 microlitre of urine is pipetted into a notch on the KOVA glasstic slide chamber. The slide consist of grid lines that is used to count the number of specific cells. Examples of possible cells found in urine includes:
1) White blood cell
2) Red Blood Cell
3) Casts
4) Crystals such as cystine and triple phosphates
5) Microorganism (bacteria, yeast, spermatozoa)

An example of a KOVA slide. (taken from http://www.mlo-online.com/articles/0104/mlo0104prodfocus.htm)

- Internal QA -
1) The tests should be performed within 2 hrs of collection. The chemical composition of urine (e.g: pH,glucose and bilirubin) may change after 2 hrs. Furthermore, any formed elements such as crystals that are actually present in the urine, may begin to deteriorate and become unrecognizable.

2) For routine urinalysis, the preferred type of urine specimen is that of a midstream clean catch. This is so as that type of specimen reflects the urine composition in the bladder and the kidney

3) Dipstick Testing
(a) The dipsticks must be protected from moisture, light, heat and volatile chemicals as they deteriorate easily.
(b) They also deteriorate with time and hence should not be used after the expiration date.
(c) Each dipstick bottle is tested routinely (daily, before dipsticks are used) for results against known commercial controls. Each of the chemical parameters of the dipstick is evaluated and the results recorded (e.g: protein 2+, pH 6.5) By doing this, the technologist performance can be compared on a daily basis and the reactivity of the strips can be checked against known standards.
(d) Only a few strips should be removed at a time and the container should be closed tightly immediately after taking out the strips.
(e) The amount of time required for the colour reaction to develop on the strip varies with each test (e.g: 2 minutes for leucocytes). A timing device (stopwatch) is used and the manufacturer’s timing instructions should be followed strictly. The strip should be held close to the colour chart in adequate lighting when reading the results.