Antegrade Versus Retrograde IV for Blood Draws

The region of the upper extremity in which the IV will be placed will be prepped with chlorhexidine and a proximal elastic tourniquet is applied to the upper arm. A 20 gauge 30 millimeter IV catheter is inserted into an upper extremity vein by an anesthesiologist in either an antegrade or retrograde direction depending on which treatment arm the study subject is randomized to.

A 20 milliliter(mL) syringe will be connected to the study IV tubing and used to aspirate 20 mL of blood from the study IV catheter. If 20 mL are unable to be aspirated over a 2 minute time frame, a proximal rubber tourniquet will be applied to the upper arm and the blood draw will be reattempted.This will occur twice throughout the study.

A 20 gauge 30 millimeter long BD Insyte(TM) Autoguard(TM) angiocatheter will be used for peripheral intravenous catheter placement as described above.

After placement of the peripheral intravenous catheter, an infusion of 0.9% normal saline will be connected to the catheter and infused at a rate of 20 milliliters per hour to keep open (TKO) for future use by preventing blood clot development within the catheter.