GentleSharp does not collect blood in and of itself. GentleSharp is used to perform a needle insertion (venipuncture/arterial puncture) and requires the blood be collected with an alternative collection device, generally associated with small volume blood sampling. Some researchers have used GentleSharp for larger volume blood collections through the use of an over-the-needle catheter.
The blood volume that GentleSharp can aid in collecting depends on multiple parameters, including the animal’s size, age, health, temperature, and blood pressure. The location of the blood collection and accuracy of the vessel puncture also affects the volume collected. GentleSharp allows for a greater blood mass and increased blood sampling success as compared to the standard bleeding method. In our research, when blood sampling mouse tail arteries, collections ranged from 1 mg to 169 mg, and an average of 38 mg of total blood per trial. Though blood volumes were not tracked, blood mass works well for approximations, with ~1 mg of blood = 1 µl blood volume.
GentleSharp allows for more successful blood sampling by inducing an electronically controlled forward and backward axial motion through a standard blood sampling needle. This oscillation reduces the amount of force required to puncture the tissue and blood vessel resulting in less tissue deformation, allowing for less needle slippage along the blood vessel. These results improve your rate of successful puncture while decreasing the required number of needle insertions to achieve the required amount of blood.
The current GentleSharp model cannot be used for injections. However, a GentleSharp device to aid with injections and dosing of animals is in development.
GentleSharp adds electronically controlled backward and forward axial motion to standard blood sampling needles. This motion reduces the required insertion force to puncture the tissue and blood vessel, resulting in less tissue deformation and less distress to the animal.
It is believed that this motion stimulates the animal’s peripheral nerves, sending a signal to the central nervous system which is faster than the one induced by acute puncture, resulting in vibration-induced anesthetic effects. We have associated the response to the Gate Control Theory of Pain, developed by Ronald Melzack (McGill University) and Patrick David Wall (Massachusetts Institute of Technology).
Needle stick injuries can occur with any sharp. Therefore it is always critical to keep vigilant awareness of the needle tip and follow your institutions protocols for handling needles. So as you work with the GentleSharp Handpiece make sure that you are aware of the needle tip and that the needle tip is pointed away from you. Only uncap the needle when you are ready to begin sampling. It’s best that before and after blood sampling, to turn off the Handpiece and set the Handpiece aside, facing the needle tipped end of the Handpiece away from your work area. Keep the needle cap on the needle before turning the Handpiece on. Follow your institution’s protocol for dealing with used needles after you are done with the needle.
To remove the needle from the GentleSharp Handpiece, place your hand around the Handpiece and move it up to the base of the needle. Twist the needle off of the Luer Connector and immediately place the needle into a Sharps disposal container as per your institutions protocols.
The GentleSharp Handpiece may be held in different positions depending, technique, target vessel, and preference of the researcher.
Most often, the Handpiece is held in an “over hand/stabbing” hold for lateral tail vein bleeding. To provide sufficient clearance for this bleed, the tail of the animal is held over the edge of the table or at an inclined angle over the table. The needle insertion occurs at a low angle to the surface of the rodent’s tail.
For submandibular and saphenous sampling, the Handpiece should be held in a “pencil” hold as the needle insertion occurs perpendicular to the surface of the animal’s skin.
The case:
Protects equipment from breakage and maintains cleanliness of the unit.
Helps with organization of your device, cords, needles, and any other blood sampling equipment.
Simplifies transportation of equipment to and from different facilities.
It is orange and can be easily distinguished from the large number of black cases found in today’s laboratories.
The training is completed via GoToMeeting or Skype and is an opportunity for you to learn about GentleSharp safety and tips regarding use of GentleSharp with your specific animal model. This is a great opportunity for you to learn from our experience and understanding of past customer use.
