Wednesday, 02 May 2018
Recommendation of Preparatory Steps Prior to Being Tested
A laboratory test aims at, among others, detecting the occurrence of diseases, determining the risk factors of the diseases, monitoring the development of the diseases as well as the medication effectiveness. The result of the laboratory test is an essential instrument in medical decision making, since the accuracy is a must. Inaccurate test results caused by less optimal preparation will fail the achievement of test and lead to inaccurate diagnosis, and will in turn result in inaccurate medical treatment.
The preparations for patients depend on the type of test itself. Here we recommend several common test preparations:
1. Patients should fast for a minimum of 10 hours prior to blood sampling, or a minimum of 8 hours for fasting blood glucose test. Fasting time for triglyceride test is minimum 12 hours.
2. During the fasting period, the patients are not allowed to eat and drink other than water.
3. Patients should restrain from smoking, chewing gum, drinking coffee and tea (even sugarless), alcohol, addictive drugs (e.g. amphetamine, morphine, heroin, cannabis) as these would compromise the results of the tests.
4. Don' t fast longer than 14 hours.
5. Avoid physical overactivity, for example exercise, prior to blood sampling.
6. Blood sampling should be conducted in the morning, between 7 - 9 am, during which the body is in basaltic state and has not performed too much activities.
Sometimes most of the patients neglect the advice because they forget it, it is not feasible for them or their bustle does not allow them to obey it. However, this test preparation is arranged by a series of considerations focusing on the patient safety.
Recommendation of preparatory steps prior to being tested is explained as follows:
1. Why fasting?
The nutrients contained in the food and beverage we consume are absorbed into the blood flow, which may directly affect the levels of blood glucose, fat and iron content. Having at least 10-12 hours of fasting (8 hours for glucose test) will decrease the variability of those substances as well as other substances within the blood. This is recommended to ensure that the test results are not compromised by the food last consumed, and to allow for correct interpretation by the doctor.
Several tests requiring fasting are, among others, the tests of glucose, cholesterol (fat/ lipid profile), urea and uric acid.
In the context of laboratory, fasting means no consumption of any foods and drinks (except water) in a specified period of time. You' d better drink sufficient water since the hydrated body will present the actual testing level.
When you have no fasting or have it in a shorter period than recommended, your test will give inaccurate result because certain tests are still dependable on food consumption. Thus, you might have to retake the test for the more accurate result. If you think that fasting will just trouble your body condition, you can consult the doctor or nurses.
2. How long should you fast?
Generally, patients are required to fast for 12 hours prior to being tested in the laboratory. Exception is for blood glucose test, where the fasting time is 8 hours. Nevertheless, different doctors or nurses might give different suggestions or advise. For the accurate test result, obey the suggestions and advice.
3. Can you take your meds before having a test?
Prior being tested, the patients are not allowed to take any medicines. Some medicines will affect the blood test result. However, it does not imply that the patients must stop consuming the medicines. For example, the oral corticosteroids might raise the cholesterol amount within blood. Thus, it is expected that you inform your medicines to the laboratory. It will help the laboratory validate your test result.
4. Why laboratory test is better conducted between 7 am and 9 am?
Laboratory test is better be conducted in the morning during which the body is in basaltic state after resting overnight. In fact, our body has a biologic variation in accordance with time. It implies that the amount of the analyte tested in the morning will give a different result if it is tested in the afternoon. For example, in cortisol hormone test, the level increases in the morning and reaches the lowest point in the afternoon. Thus, make sure that you follow the instruction of the doctor prior to being tested.
Correct preparation for laboratory test is a must in order to obtain accurate test results and to allow correct diagnosis and administration of medication by the attending doctor. Do those steps correctly to avoid retest or additional test that is otherwise unnecessary.