Venipuncture

To draw blood from a canine patient from the cephalic vein you must first gather the supplies you need to collect the samples. You need isopropyl alcohol, a syringe and needle combination; usually with a 22g needle, and the proper tubes to put the sample in. Second, put the patient in proper restraint. A technician should be holding the patient and occluding the vein of either one of the front legs. The technician drawing the blood should then wet the area over the cephalic vein with isopropyl alcohol. With gloved hands you should then be able to feel the cephalic vein by tapping and rolling your finger over the area where the vein should anatomically be; which is usually half way between the paw and the elbow on the cranial side of the leg. You should then uncap your needle. While holding the leg in your non-dominant hand you should use your dominant hand to insert the needle, bevel up, into the vein. A flash of blood should appear in the hub of the syringe. You should then gently and slowly pull back the plunger of the syringe; blood should fill the syringe. Once you have the desired amount, which for most dogs is usually going to be about 3ml, you can place gauze over the area where the needle had entered the skin quickly after removing the needle from the skin. The person restraining the dog should then take over holding the gauze and applying pressure to stop the bleeding. The technician that has just drawn then blood should recap the needle using a one hand technique for safety and remove the needle from the syringe. You should then uncap the desired tubes to place the blood in and plunge the blood slowly into the tube. Replace the cap to the tube.By removing the cap of the tube rather than piercing the tube you avoid hemolysis of the sample. If the tube requires inversion, invert the tube as needed. You then should dispose of the syringe and needle in a sharps container. At this point most patients can now remove the gauze from their leg. If there is still bleeding, you can apply a pressure bandage for about 10 minutes.