Trick of the Trade: Upsize the IV with the tourniquet infusion technique

peripheral iv catheterThere you are, middle of the night and EMS just brought you one of the sickest of the sick: a septic-looking, chronically ill-appearing, frail, and malnourished patient with low blood pressures. They need vascular access for fluids, antibiotics, and possibly even vasopressors. The patient arrives with only a 22-gauge peripheral IV in the hand. You ask for two large bore IVs. But unfortunately, your best nurses and techs can’t find a vein, and their initial attempts are unsuccessful. Do you move right towards ultrasound-guided placement, intraosseous needle, or a central line? What if the patient only needs a fluid bolus, antibiotics, and admission to the floor?

Trick of the Trade: Tourniquet infusion technique

The tourniquet-infusion technique provides a method to increase the chance of a successfully placed larger bore peripheral IV in the volume-depleted patient.


  1. Apply a tourniquet to the extremity, proximal to the existing smaller-gauge IV access site.
  2. Rapidly infuse 50-100 mL of IV fluids, causing distension of the venous system between the IV and the tourniquet. This distension creates a larger target for venous cannulation in volume-depleted patients.
trick tourniquet infusion technique dilate upsizing vein arm peripheral IV

Tourniquet Infusion Technique: After applying a tourniquet and instillation of an IV bolus of fluids through a small distal 22-gauge IV, large veins are more visible for a second larger-bore IV



This technique has been described in the literature for decades [1-3], and has been anecdotally successful in clinical practice. Its methodology capitalizes on pre-existing or easily-placed distal small gauge access (i.e., a 22g IV in the hand) as a stepping stone to larger venous cannulation.

Quinn and Sheikh investigated the employment of this technique for 22 adult patients with an acute abdomen who had been referred from the ED in hypovolemic shock. A peripheral IV had not been obtained in any of these patients using standard cannulation methods. By employing this tourniquet-infusion technique to upsize the IVs, they were able to successfully obtain adequate access for resuscitation in 15 of the 22 patients (68%). They noted no complications secondary to this technique. The authors noted that of the other 7 patients in this small study, 2 died and 5 required ultrasound-guided IJ venous line placement. In total, 15 patients were potentially spared unnecessary central venous catheterization. This technique is a simple, quick, and effective way of establishing a more appropriate line for resuscitation of sicker patients [1].


  • For large-bore antecubital IV placement, consider placing a tourniquet in close proximity and just proximal to the elbow joint.
  • Consider the patient’s cardiac and pulmonary history to ensure that an additional fluid bolus is clinically appropriate.


  1. Stein JI. A new technique for obtaining large-bore peripheral intravenous access. Anesthesiology. 2005 Sep;103(3):670. doi: 10.1097/00000542-200509000-00041. PMID: 16130004.
  2. Quinn LM, Sheikh A. Establishing intravenous access in an emergency situation. Emerg Med J. 2014 Jul;31(7):593. doi: 10.1136/emermed-2012-202106. Epub 2013 Jun 15. PMID: 23771897.
  3. Williams DJ, Bayliss R, Hinchliffe R. Surgical technique. Intravenous access: obtaining large-bore access in the shocked patient. Ann R Coll Surg Engl. 1997 Nov;79(6):466. PMID: 9422881; PMCID: PMC2502954.