What is a key difference in technique between intravenous injection and intravenous blood collection?

What is a key difference in technique between intravenous injection and intravenous blood collection?

• A. Only concave needles can be used for intravenous injections.
• B. A syringe cannot be used for blood withdrawal.
• C. Pressure applied proximal to the injection site is released prior to injecting, and pressure is maintained when drawing blood.
• D. Pressure does not need to be applied to the site after the procedure.

Answer: (C)

The technique difference hinges on how you manage venous pressure with a proximal compression (the tourniquet) to distend the vein. For intravenous injections, you release the proximal pressure just before you insert the needle so the vein isn’t constricted and the fluid can enter the bloodstream smoothly. After the injection, you may still apply pressure to stop any leakage, but the key is not to keep the vein under high proximal pressure when you’re delivering the drug. For intravenous blood collection, you keep the pressure proximal to the site during the preparation and puncture to keep the vein distended and stable, making it easier to draw a steady blood flow into the collection device. Releasing this pressure during collection would allow the vein to collapse or the flow to waver, hindering obtaining an adequate sample. The other options aren’t accurate: needle shape isn’t defined by this difference, syringes can be used for blood withdrawal, and applying pressure is still needed after the procedure to stop bleeding.

The technique difference hinges on how you manage venous pressure with a proximal compression (the tourniquet) to distend the vein. For intravenous injections, you release the proximal pressure just before you insert the needle so the vein isn’t constricted and the fluid can enter the bloodstream smoothly. After the injection, you may still apply pressure to stop any leakage, but the key is not to keep the vein under high proximal pressure when you’re delivering the drug.

For intravenous blood collection, you keep the pressure proximal to the site during the preparation and puncture to keep the vein distended and stable, making it easier to draw a steady blood flow into the collection device. Releasing this pressure during collection would allow the vein to collapse or the flow to waver, hindering obtaining an adequate sample.

The other options aren’t accurate: needle shape isn’t defined by this difference, syringes can be used for blood withdrawal, and applying pressure is still needed after the procedure to stop bleeding.