Blood Sampling Techniques

I. Venous Samples

1. Sites include jugular, cephalic and saphenous veins.
2. Equipment: needles, syringes, blood collection tubes, alcohol and/or povidone iodine Betadine® gauze and tape.
3. Technique

1. Prepare site with alcohol and/or povidone iodine (Betadine®) (for blood cultures shave site and do complete sterile prep, Blood Culture).
2. Use smallest needle practical.
3. After obtaining sample apply firm, steady pressure to puncture site using gauze pledget secured with tape or held by hand.

II. Arterial Samples for Blood Gas Analysis

1. Sites include facial, greater metatarsal, femoral and transverse facial arteries. (See Fig. 1).
2. Equipment: heparinized 3 cc syringe, 25 gauge needle, rubber stopper, ice water bath, alcohol and povidone (Betadine), gauze and tape.
3. Technique: Squeeze all the heparin out of the syringe so it is just in the hub.

1. Prepare site (may be shaved).
2. Use two fingers to palpate the artery. Start nearly perpendicular with needle on syringe.
3. After penetrating the skin and wall of artery, slowly advance or withdraw the needle until blood is obtained.
4. Tap air bubbles out of syringe, insert needle into a rubber stopper like a vacutainer top and place sample in ice water bath.
5. Apply firm pressure to puncture site for 2-5 minutes.
6. A 2.5 -3 cc volume of blood is adequate.
7. Record body temperature and submit to lab with sample.

1. Sample is stable in ice water for 6 hours.

Figure 1. Sites for arterial blood gas sampling in the neonatal foal.