- Biological Application
3.1 Biological Interface of Vein Locator:
Generally, the vein locator used to create reflection image of the blood vessels on the skin by using led system.In addition,vein locator use in clinical environment to via physicians or nurses to help visulation of blood vessels and entrance of the blood vessels during the blood taking process.
In this part of the report is explaining the biological interface of the machine such as blood vessels, arm veins, what is the name of arm veins, the ideal arm vein for blood taking process, their applications, the ideal diameter of the arm veins and the normal blood flow velocity for the arm veins.
3.1.1 Blood Vessels:
Blood vessel are organs of the circulatory system. Their duty is transport blood through the human body. Fundamental types of the blood vessels are the arteries which carry blood away from the heart and the veins which carry blood from the capillaries back toward the heart. The word vascular, meaning relating to the blood vessels, is derived from the Latin vas, meaning vessel.
During blood taking process, most preferable blood vessel are arm veins.The most widely used field of the vein locator is visulating of arm veins easily.
3.1.2 Arm Veins:
There are three types of arm vein that used in the blood taking.
- Basilic Vein-Shown in the forearm and arm,it divides to join the brachial vein.
- Cephalic Vein-shown in both forearm and arm, it can be followed proximally where it empties into the axillary vein.
- Antecubital Vein
- Median Vein
- Median Cubital vein-A superficial vein,most commonly used for venipuncture,it lies over the cubital fossa and serves as an anastomosis between the cephalic and basilic veins.
3.1.3 Features of Arm Veins:
For opening the peripheral path of vein, arm veins are use.
The most widely used arm veins are basilic vein (vena basilica) and cephalic vein (vena cephalica).
Generally, basilic vein is the fist choice for entrance to vein when cephalic vein is used during blood taking that cause difficulty to push forward the injector through the vein. Because cephalic vein join together with axillary veins with vertical angle.
3.2 Structure of Basilic Vein:
The basilic vein passes along the back of the forearm on the ulnar side for a distance and then curves to the surface below the elbow. It continues to move up the medial side until it reaches the middle of the upper arm. There, it enters deep into the tissues and joins the brachial vein. As the basilic and brachial veins merge, they form the axillary vein. (Dr. Duran Karabel, 2007)
3.2.1 What is the normal diameter of the Basilic Vein?
In normal conditions the internal diameter of basilic vein is between the 4.96-5.09 mm for healthy people which don’t have any disease. 25
3.2.2 What is the normal blood flow velocity of the Basilic Vein?
In normal conditions the average internal blood flow of basilic vein is about 150mm/s for again healty people.
3.3 Structure of other arm veins:
Generally, in normal condition without any effect to effect the veins, the diameter of cephalic and median vein has same diameter which is between 2-2.6 mm and its average is 2.5 as a result of research.
The blood flow velocity of all veins are same which is about 150 mm/s as we work before in basilica vein.
But arteries have more blood flow velocity is about 500 mm/s.
WE WILL USE PELTIERTO EXPAND BASILIC VEIN(VASODILATION) FOR MAKE EASY TO FIND THE VEIN DURING BLOOD TAKING.
Vasodilation refers to the widening of blood vessels. It results from relaxation of smooth muscles cells within the vessel walls, in particular in the large veins, large arteries, and smaller arterioles. In essence, the process is the opposite of vasoconstriction, which is the narrowing of blood vessels.
When blood vessels dilate, the flow of blood is increased due to a decrease in vascular resistance. Therefore, dilation of arterial blood vessels (mainly the arterioles) decreases blood pressure. The response may be intrinsic (due to local processes in the surrounding tissue) or extrinsic . In addition, the response may be localized to a specific organ (depending on the metabolic needs of a particular tissue, as during strenuous exercise), or it may be systemic.
3.4.1 Vasodilation of basilic vein by using heat source:
As we know the normal diameter of basilic vein is around 5 mm for people without any disease. But in old people,in children,in obesity and in the cold weather the basilic vein is become narrow. So in this point we will apply heat source on basilic vein, make it expand which cause vasodilation. When the heat source will active, the diameter of the basilic vein increase between 1.28-1.84 mm and it becomes suitable condition for blood taking. Also expanding basilic vein may lead to increase blood flow velocity (normal 150mm/s) which make easy blood taking again.
3.5 What is the most ideal amount of heating?
We want to expand basilic vein by using heat source. But when we use heat source, the amount of source must just increase the diameter of vein it should not be burn the people skin. So the ideal value of heating is about 40-45 degree celcius which just expand the vein.
Lastly, we will use variable resistor( potentiometer) in heat source to set the heat at ideal condition about 40 degree celcius.
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