The goal of the following procedure is to collect dried blood spots or DBSA simple cost-effective alternative to venipuncture. This is accomplished by first having the participant warm their hands. Next, a finger is selected and cleaned.
The hand and finger are milked to increase the blood flow at the puncture site. The finger is then punctured with a safety lancet and blood spots are collected on filter paper. Finally, the puncture site is cleaned and bandaged.
Once the samples are dried, the collected sample is packaged for storage or shipment. Ultimately, successfully collected dried blood spots can be analyzed for a number of biomarkers, such as cholesterol, C-reactive protein, and glycosylated hemoglobin. The main advantage of this technique over venipuncture is that dried blood spot collection is simple, relatively painless, and less invasive than venipuncture.
While mastery of this technique requires more time, it can be learned and implemented with a few days of instruction and training Because they're easy to obtain, transport and analyze dried blood spots allow the study of biomarkers in field and population level. Research where collecting venipuncture samples is difficult or unfeasible. Biomarkers measured from dried blood spots can provide valuable information about biological processes underlying health or chronic disease risk.
When collecting dried blood spot samples, always remember to use personal protective equipment such as a lab coat, gloves, long pants, clothes toed shoes, a lab protecting under pad and safety glasses if desired. After obtaining consent, ask which hand the participant would prefer to use and then select a finger for collection. Next, have the participant rub their hands together to warm them and to stimulate blood flow.
Clean the selected finger two times with an alcohol pad, allowing the alcohol to fully dry each time. As with all used collection materials, immediately dispose of the wipes in a biohazard waste container. Now secure the participant's arm to prevent movement during collection, and to relax the arm and hand muscles, keep the participant's hand positioned comfortably below heart level with the muscles relaxed.
To facilitate blood flow, use thumb and index finger to gently milk the hand and selected finger by slowly and firmly squeezing it while moving the grasp from the palm to the fingertip. Pulling the blood towards the fingertip tip. Then press a micro lancet firmly against the participant's finger perpendicular to the fingerprint and between the center of the finger and the nail beds on the ulnar side of the finger and discharge the lance.
Immediately dispose of the used lancet in the sharps container, and then wipe the first drop of blood away with a sterile gauze pad. Immediately dispose of the gauze and then gently milk the hand starting at the wrist and working down to the base of the finger, keeping the participant's hand below the heart with a downward angle. Milk the finger until a large drop is hanging from the fingertip, and then carefully position a piece of collection paper below the finger and allow the drop to fall of its own weight.
If the blood is too viscous or the drops are too small to fall of their own weight, slowly bring the collection paper into contact with the blood drop to collect it via capillary action without touching the finger to the collection paper. To prevent clotting, continue milking the participant's finger to keep the blood flowing. Once the dried blood spots have been collected, clean the puncture site of any extraneous blood.
Then bandage the puncture site to prevent potential contamination. Ensuring the collection paper can stand freely to allow airflow behind the sample. Place the collection card on a protective underpad.
Spacing the cards to allow good airflow between them. Allow the samples at least 15 to 30 minutes to dry. A dark red brown color spot indicates sufficient dryness for storage.
After confirming the samples are dry, close the collection card cover. Next place a desiccant pouch into a biohazard specimen bag, and then place the collection card into the bag without letting the blood samples touch the outside. Flatten the bag to remove the excess air and then seal the bag tightly.
Then, with all the blood collection steps complete, remove the protective personal equipment. Finally, place the bagged sample into a storage cooler for transport or temporary storage, avoiding elevated temperatures. Here, valid dried blood collections are depicted.
The samples are at least 0.375 inches in diameter as measured from the back of the collection card and are of approximately equal size on either side of the collection area together indicating complete saturation through the filter paper. Problematic dried blood spots are demonstrated for comparison in these images. For example, spots should not overlap one another as overlapping results in excess sample.
Preventing knowledge of the blood sample volume spots should not be smeared on the collection area as this represents incomplete saturation and is typically accompanied with a lack of penetration to the opposite side of the paper. Successful implementation of DBS samples in population level studies allows analysis of biomarkers where venipuncture sampling might be prohibitive. These graphs demonstrate such an application in a study of employee cardiometabolic disease risk as predicted by flexible managerial style.
For example, the total cholesterol in the DBS samples in this experiment was determined to correlate with significantly increased odds of having two or more cardiovascular risks in employees who worked for managers with med or low work family scores. After watching this video, you should understand how to safely and properly collect package and store dry blood spots. Once mastered, this technique can be done in less than 10 minutes with little inconvenience to the participant.
While performing this procedure, it is important to follow all standard precautions. Personal protective equipment should be used at all times and contaminated material and bio waste must be disposed of appropriately By collecting biomarkers where people live or work free range humans, if you will, and in a way that isn't uncomfortable for them. We can have greater levels of participation in our research studies.
We are also able to evaluate the mechanisms by which our environment and social context impact health and disease.
