Faq

Laboratory tests are medical procedures that involve testing samples of blood, urine, or other tissues or substances in the body.

Lab tests show whether or not your results fall within normal ranges. Normal test values are usually given as a range, rather than as a specific number, because normal values vary from person to person. What is normal for one person may not be normal for another person.

Some laboratory tests are precise, reliable indicators of specific health problems, while others provide more general information that gives doctors clues to your possible health problems. Information obtained from laboratory tests may help doctors decide whether other tests or procedures are needed to make a diagnosis or to develop or revise a previous treatment plan. All laboratory test results must be interpreted within the context of your overall health and should be used along with other exams or tests.

There are many ways in which blood can be drawn from a vein. The best method varies with the age of the patient, equipment available, and tests required.

Most blood collection in the US and UK is done with an evacuated tube system. Two common systems are Vacutainer and Vacuette. The equipment consists of a plastic hub, a hypodermic needle, and a vacuum tube. The conventional method uses a plastic disposable needle and syringe for drawing blood. In our country, the conventional method is still prevalent in most places.

The vacutainer system allows mixing of the right amount of blood with prefilled measured additives. There is no variation of cell morphology and other biochemical parameters due to squeezing of the blood sample through the conventional syringe. Multiple vacuum tubes can be attached to and removed in turn from a single needle, allowing different kinds of blood samples to be obtained from a single venipuncture.

However, care has to be taken to put the needle properly in a good vein, in a single prick, otherwise the proportion of blood to additive gets altered. Moreover, the phlebotomist has to be efficient in venipuncture, because you cannot make out if the needle is in the vein until you attach it to the vacuum tube.

With the vacuum tube system, the needle pierces the top of the sample tube and potentially comes in contact with the additives in the tube. As it is a hollow needle, some of this can be carried into the next tube and contaminate it. The most likely additive to cause trouble is EDTA which will affect the coagulation time assays and by chelating some of the metal ions may interfere with some of the biochemistry results (especially potassium). Thus EDTA samples should be drawn last in most cases and plain tubes must be drawn first.

Under certain circumstances, such as in children, or when the veins are difficult to find, a syringe with a butterfly needle may be used.

Proper sample collection is the first step to correct results. This includes timing of sample collection, whether any special preparation is required, whether any drug has to be stopped before getting the test done, proper mixing of sample with correct anticoagulant, and such other factors. Lipaemic or hemolysed blood samples may give inaccurate results.

Ideally the samples should be tested immediately after collection, especially urine and stool samples. Some samples can be transported. However, transportation of sample needs stringent temperature and leak control measures, otherwise loss of quality can occur.

Empty your bladder when you first get up in the morning. DISCARD this Urine. Record the time on the container.

From that time, save all urine up to and including the first morning specimen at the end of the 24 hours ( or other designated time period). During collection and until the specimen is brought to the laboratory, the urine container should be refrigerated or kept on ice(in a bucket).

Record on the urine container, the time the last part of the specimen was collected.

Be careful not to deposit toilet tissue in the specimen or allow it to become contaminated with fecal material.

If the container has a preservative, (orange sticker or written), handle the container with caution. Specific instructions are available on the yellow label, and/or by calling the laboratory.

Bring the container with the urine to the laboratory as soon as possible. As a part of some tests, a blood sample must also be collected. Check with the laboratory to verify that a sample is not needed.

The mouth should be free of any foreign matter. If available, the mouth may be rinsed with filtered or sterile water prior to collection. Sputum should be coughed from deep in the chest and coughed into the plastic collection bottle. To reduce the likelihood of transmission to others, patients are encouraged to collect their sputum specimens outdoors whenever possible.

Sputum specimens will be collected in the early morning if possible.

A hot drink or breathing deeply over a steam vessel (i.e. pan of boiling water) may help raise sputum.

A specimen of 1-2 teaspoons in volume is adequate. The container should not be more than ? full. Following collection, the top will be placed securely on the plastic bottle. Unless instructed otherwise, collect 3 sputum specimens on 3 consecutive days.

The specimen bottle must be labeled with the patient?s name, date of birth and the date the specimen was collected.

The laboratory slip must be completed with the patient?s name, date of birth and the date the specimen was collected.

The plastic bottle and the lab slip will then be placed in the mailing tube with the screw top securely closed.

Patient must give his/her blood sample (for post lunch sugar test) 2hrs after finishing the lunch. The lunch should consist of routine meal which the patient has regularly.

For all practical and routine purposes, it is ideal to transfuse to the patient the same group of blood which he/she belongs to. It is only under very dire emergencies that we take O group as universal donor and AB groups as universal recipient. Under no circumstances O group can get any other blood except O. Similarly A group patient cannot be given B group blood and vice versa.

Complete Blood Count will tell us Hemoglobin, Red Blood Cell count, Red cell indices, Total White Blood Cell count, and Differential count of White blood cells, Platelet count and findings of Peripheral smear.

No need to come fasting. Patient can give a blood sample at any time.

But patient should give us the following information:

Exact Date of Birth

Weight in Kg

Height in cms

Exact Date of Last Menstrual Period

Xerox of Latest USG Report

Before submitting, keep the following in mind:

Abstinence should be ensured for 4-5 days.

The total number of days since last ejaculation should be no longer than 4-5 days.

Prolonged abstinence (greater than 5 days) may increase the numbers of dead or poorly motile sperm cells.

The procedure is painless and similar to routine gynaecologic (per vaginal) examination. Sometimes, the patient might feel some discomfort. The doctor inserts an instrument called a speculum (it looks like a duck's bill) into the vagina to see the cervix. Then, using a tiny spatula or brush, the doc takes a sample of cells from the cervix. The cells are sent to a lab for examination.

HIV p24 antigen

HIV antibodies

Western Blot test and PCR test