Brainstorm / Concept Selection – BME66 Group Website

Objective: Design a convenient/efficient pediatric blood sampling method

Target Customer: children, ages 5 months and up

Brainstorming

Imaging/Increasing Vein Visibility
1. Device that shows and marks veins through skin contact
  1. Single-person operation to locate and mark veins, followed by blood drawing at the marked position.
  2. Possible methods for imaging:
    1. Past vein imaging devices have used near-infrared light
    2. Other medical devices have used thermal imaging
    3. Ultrasound / sound waves could also be used to detect location of veins
    4. Transillumination, which involves shining an otoscope beneath the skin surface of a baby’s foot, finger, palm, or leg could be used to visualize vasculature via skin color.
  3. Sub Ideas:
    1. Grid marking of the skin to indicate approximate vein location
    2. Attachable device component to improve suitability for use with babies, such as an extension piece that the baby can hold onto to keep their arm straight and minimize stress.
2. Device that shows location of veins without skin contact and projects image of vein locations onto the skin
  1. Skin marking is not necessary as the needle insertion can be guided by the projected image.
  2. Requires more than one person to operate, with one person holding the device and the other inserting the needle.
  3. Similar ideas have already been developed.
3. A finger flexion device to enhance vein visibility using tension generated by flexing fingers
  1. In older patients, healthcare providers often tell them to make a fist to increase vein visibility. The same principle can be applied to babies
  2. The baby’s grasping reflex will cause them to close their fingers around an object placed in their palm. Grasping can be calming for the baby
  3. One drawback is that the grasping reflex is only present until about 6 months of age. To address this, the device could be a toy that the baby would want to grasp even without the reflex
  4. The device could be attached to their fingers to create extra tension when the baby grasps the object, causing veins to become more visible
4. Administering a dilating agent with needle free injection subcutaneously to enhance the visibility of veins.
  1. Use j-tip needle free injection
    1. Uses compressed CO2 to push in a numbing agent that dissolves into the subdermal area
5. Improving a standard tourniquet
  1. Rubber band-like device could be wrapped around the forearm at the blood-drawing location, to induce vein distension
Alternative methods of blood drawing
1. Microneedle patch on skin
  1. A patch placed on the baby’s arm using microneedles to extract blood through capillary action, with needle penetration at a depth that corresponds to vessel location.
  2. Offers a painless alternative to hypodermic needle usage.
  3. Potentially incorporates illumination features that activate upon vein location or blood collection initiation.
2. Numbing agent with needle free injections to minimize pain
  1. Could apply similar principles to needle free drug delivery injections
3. Draw blood from an alternative location instead of the arm
  1. Collect blood from the arm, hand, finger (in the case of small blood samples), or leg, with the potential for device attachment to various regions of a baby’s body.
  2. It is important to specify the required blood volume for sampling, as finger sticks may be suitable only for small quantities of blood.
Minimizing movement
1. Minimize movement with a toy or device
  1. Can be used to stabilize a baby’s hand and reduce movement during blood drawing, potentially utilizing an object placed in their hand or a gripping mechanism.
  2. Could include a toy component to keep baby distracted/ occupied
  3. Could include a component that creates pressure similar to tourniquet that fits babies

Baseline

Blood is drawn from a vein in the upper forearm for babies over 5 months old
A tourniquet is used to increase vein visibility, but they are usually too big for babies and non-adjustable
The area is disinfected before the procedure
Typically, a butterfly needle with a metal tip is used to puncture the skin, and a vacuum system draws the blood up
Veins can be more difficult to visualize in babies due to their smaller anatomy and increased subcutaneous fat
Repeated punctures may be required, causing stress for babies and resulting in additional movement and vein constriction, making veins even harder to find
Caretakers may also experience stress due to difficulties in finding veins

Pugh Matrix

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Using the number scale was difficult because we had to decide whether the proposed solution was a little better or much better than reference. Creating the Pugh Matrix with ‘+’ or ‘-’ could have provided a less precise but more accurate method for determining whether an idea was worse or better than the baseline.
User requirement titled “straightforward and efficient” could be conflicting in certain contexts. A device could be easy for health professionals to use, but it could take more time to perform its function. If it takes more time for its intended function, does that still make it efficient even though it is straightforward to use?
Improving the tourniquet had the greatest weighted total while the dilating agent (with needle free injection) had the lowest weighted total.
User requirements such as cost, portability, and compatibility with the baby’s arm depend on the specifications of the proposed solutions. For example, if the tourniquet is made with an expensive material, it would be more expensive than the baseline. However, if the design and material were relatively cheap, then the Pugh Matrix scoring would be less than baseline.

Possible Hybrids

A microneedle patch could be used to first administer a numbing agent, then draw blood
- This would increase scores for minimizing pain and anxiety while also offering a way to effectively draw the blood
Alternatively, the microneedle patch could be used to administer a numbing and dilating agent. The patch could then be removed so another needle could be inserted to the dilated and numbed vein
- This would increase scores for minimizing pain and anxiety while also offering a way to effectively draw the blood
- However, additional usage drugs would decrease scores for cost effectiveness
Improving tourniquets, using a finger flexing device, and using a toy to minimize movement could be implemented in conjunction with a vein finder device (either touching the skin or not)
- This would improve scores for vein visibility, reducing anxiety, and compatibility with the baby’s anatomy

Concept Solution

Option 1– Use a finger flexing device in conjunction with a standard tourniquet to reduce stress and increase vein visibility
- A tourniquet is standard practice for blood draws. This would help increase vein visibility by allowing blood to pool into the lower half of the arm
- Vein visibility would be enhanced by the finger flexing device. This would also help to calm the baby by activating the grasping reflex, or by providing a toy that the baby associates with positive emotions. This would reduce stress and vasoconstriction while improving vein visibility
- Necessary Refinements
  - The device would need to provide enough tension so that making a fist will cause enough finger flexion to make veins more visible, but the tension must not be so great that the baby cannot make a fist or is hurt
  - The device must be easily attachable to the baby’s fingers without causing pain or anxiety
  - The accuracy of the device would need to be determined to see if it is a reliable method for improving vein visibility
Option 2 – Use a microneedle patch
- A standard tourniquet could be used to increase vein visibility
- The microneedle patch could be placed on the skin in an area that is approximately near a vein
- The microneedle would be able to draw blood via capillary action
- This would reduce pain and anxiety associated with needles and repeated punctures
- Additionally, the location of the vein does not need to be as precise because the patch will cover an area of skin
- Necessary Refinements
  - The microneedles would need to be designed so they can penetrate deep enough into the skin to collect blood
  - The microneedles must be able to draw blood in sufficient quantities for health assays
  - Optimal microneedle materials need to be researched further

Reflection

These options were chosen to satisfy the more heavily weighted criteria. We chose options that would be novel, effective, and easy to implement in a medical setting.
As a group, we are comfortable with the two preliminary options chosen. We plan to research them further to address the necessary refinements. This will help us decide which idea to ultimately pursue and develop
To feel more comfortable with the decisions, we hope to get more clarification on the extent to which we need to develop a working product. This would better inform us about the scope and feasibility of our project