Table of Contents
Why are the thumb and little finger not pricked for blood sampling?
The thumb has a pulse and is likely to bleed excessively. The index finger can be calloused or sensitive and the little finger does not have enough tissue to prevent hitting the bone with the lancet.
Why is it hard to get blood from my finger?
If you typically have issues getting a blood drop to form, running your hands under warm water as you wash them or massaging your finger can help with blood flow. Tip: Using alcohol wipes can dry your skin, potentially making it hard to get a blood drop. This may affect your test results.
Why is ring finger preferred for capillary?
The middle or ring finger is preferred as having the greatest depth of tissue beneath the skin and hence offering the least chances of injury.
Is there any difference in the quality of blood obtained by venipuncture and capillary puncture?
The differences between capillary and venous blood in most cases are minimal. However, there are some discrepancies in hemoglobin and hematocrit values and in platelet counts. It is well known that capillary blood has higher hemoglobin and hematocrit values than venous blood.
What type of blood is collected during a skin puncture?
PRINCIPLE. The skin puncture method for blood collection is used when it is impossible or impractical to obtain a venous blood sample. The following disadvantages of this technique should be considered whenever selecting this method as an option. Only small volumes of sample can be obtained.
Is capillary blood venous or arterial?
Capillary blood is a combination of arterial and venous blood. From the right side of the heart through the lungs, oxygenated arterial blood flows into the capillaries. There, oxygen and nutrients are distributed and exchanged for carbon dioxide.
Which finger is best for pricking blood?
Prick your finger with the lancing device at the sides of the finger as there are less nerve ending here than at the tips or the ‘pads’. Recommended finger: the World Health Organisation recommends the middle or ring fingers are used for blood glucose tests (second and third fingers).
Why should blood cultures never be collected by skin dermal puncture?
Povidone iodine should not be used for capillary skin puncture (13) because it can contaminate blood and lead to inflated measurements of potassium, phosphorous or uric acid (36).
What are the rules for capillary blood sampling from finger?
The following rules apply when capillary blood sampling is performed from a finger: The puncture must be on the palm-up surface of the distal segment (fingertip) of the middle or ring finger (Figure 3, a). The puncture must be performed on the side of the fingertip where tissue depth is sufficient to prevent bone injury.
How do you take care of a capillary haematology specimen?
As described above for adult patients, collect the capillary haematology specimen first, followed by the chemistry and blood bank specimens. Clean up blood spills. Collect all equipment used in the procedure, being careful to remove all items from the patient’s bed or cot; to avoid accidents, DO NOT leave anything behind.
What are the possible complications of capillary sampling?
Complications that can arise in capillary sampling include: collapse of veins if the tibial artery is lacerated from puncturing the medial aspect of the heel; osteomyelitis of the heel bone (calcaneus) (68); nerve damage if the fingers of neonates are punctured (69); haematoma and loss of access to the venous branch used;
What happens if you squeeze a blood sample too tightly?
Wipe away the first drop of blood because it may be contaminated with tissue fluid or debris (sloughing skin). Avoid squeezing the finger or heel too tightly because this dilutes the specimen with tissue fluid (plasma) and increases the probability of haemolysis (60).