Peripheral Intravenous Access

The ability to obtain intravenous (IV) access is an essential skill in medicine and is performed in a variety of settings by paramedics, nurses and physicians. Although the procedure can appear deceptively simple when performed by an expert, it is in fact a difficult skill which requires considerable practice to perfect.

The rate of fluid flow is proportional to radius to the power of four, and inversely proportional to length; therefore fluids run fastest through a shorter and larger diameter tube. Also note that the smaller the gauge of a needle, the larger its diameter i.e. a 14 gauge needle has larger diameter than a 21 gauge needle.

By starting a peripheral IV, you gain access to the peripheral circulation of a patient, which will enable you to sample blood as well as infuse fluids and IV medications. IV access is essential to manage problems in all critically ill patients. High volume fluid resuscitation may be required for the trauma patient, in which case at least two large bore (14-16 G) IV catheters are usually inserted. All critically ill patients require IV access in anticipation of future potential problems, when fluid and/or medication resuscitation may be necessary.

Some patients have anatomy that poses a risk for fluid extravasation or inadequate flow and peripheral IVs should be avoided in these situations. Examples include extremities that have massive edema, burns or injury; in these cases other IV sites need to be accessed. For the patient with severe abdominal trauma, it is preferable to start the IV in an upper extremity because of the potential for injury to vessels between the lower extremities and the heart. For the patient with cellulitis of an extremity, the area of infection should be avoided when starting an IV because of the risk of inoculating the circulation with bacteria. As well, an extremity with an indwelling fistula or on the same side of a mastectomy (occasionally a problem) should be avoided because of concerns about adequate vascular flow.

The main complications of an IV catheter are infection at the site and development of superficial thrombophlebitis in the vein that is catheterized. It is also common for the IV sites to leak interstitially.

The potential for contact with a patient's blood while starting an IV is high and increases with the inexperience of the operator. Gloves must be worn while starting an IV and if the risk of blood splatter is high, such as an agitated patient, the operator should consider face and eye protection as well as a gown. Trauma protocol calls for all team members to wear gloves, face and eye protection and gowns. As well, once removed from the protective sheath, IV catheters should either go into the patient or into an appropriate sharps container.

Important: Recapping needles, putting catheters back into their sheath or dropping sharps to the floor (an unfortunately common practice in trauma) should be strictly avoided. Recapping of needles is one of the commonest causes of preventable needle stick injuries in health care workers.

Generally IV's are started at the most peripheral site that is available and appropriate for the situation. This allows cannulation of a more proximal site if your initial attempt fails. If you puncture a proximal vein first, and then try to start an IV distal to that site, the fluid may leak from the injured proximal vessel. The preferred site in the emergency department is the veins of the forearm, followed by the median cubital vein that crosses the antecubital fossa. In trauma patients, it is common to go directly to the median cubital vein as the first choice because it will accommodate a large bore IV and it is generally easy to catheterize. In circumstances where the veins of the upper extremities are inaccessible, the veins of the dorsum of the foot or the saphenous vein of the lower leg can be used. In circumstances in which no peripheral IV access is possible a central IV can be started.

All necessary equipment should be prepared, assembled and available at the bedside prior to starting the IV. Basic equipment includes:

To prepare the IV line, protective caps are removed from the fluid bag and the spiked end of the IV tubing. The regulating clamp for the IV line should be closed. The spiked end of the IV tubing is inserted into the receptacle on the IV bag while holding the IV bag inverted. The bag is then held upright with the IV line hanging from the bottom. The drip chamber should be filled half-way by pinching it and releasing. Following this the bag should be hung for the IV pole, at a point above the patient, and the regulating clamp should be opened to "flush" the line of air bubbles prior to connection to the patient.

Assemble your equipment.
Don a pair of appropriately sized non-latex examination gloves.
Apply tourniquet to the IV arm above the site.
Visualize and palpate the vein.
Cleanse the site with a chlorhexidine swab using an expanding circular motion.
Prepare and inspect the catheter:
Remove the catheter from the package.
Push down on the flashback chamber to ensure it is tight.
Remove the protective cover.
Inspect the catheter and needle for any damage or contaminants.
Spin the hub of the catheter to ensure that it moves freely on the needle
Do not move the catheter tip over the bevel of the stylet.
Stabilize the vein and apply countertension to the skin.
Insert the stylet through the skin and then reduce the angle as you advance
through the vein.
Observe for "flash back" as blood slowly fills the flash back chamber.
Advance the needle approximately 1 cm further into the vein.
Holding the end of the catheter with your thumb and index finger, pull the
needle (only) back 1 cm with your middle finger.
Slowly advance the catheter into the vein while keeping tension on the vein and skin.
Remove the tourniquet.
Secure the catheter by placing the Tegaderm™ over the lower half of the catheter hub taking care not to cover the IV tubing connection
Occlude the distal end of the catheter with the 3rd, 4th and 5th fingers of your non-dominant hand.
Secure the catheter hub with your thumb and index finger and carefully remove the needle.
Place the needle into the sharps container.
Remove the cover from the end of the IV tubing and insert the IV tubing into the hub of the catheter.
Secure the tubing to the catheter by screwing the Luer Lock tight.
Open up the IV roller clamp and observe for drips forming in the drip chamber.
Check that the IV is infusing into the vein by occluding the vein distal to the catheter and observing that the drips stop forming and then restart once the vein is released.
Adjust the IV drop to keep the vein open rate (TKVO) of approximately 30 - 60 mL/hr (one drop every 5 - 10 seconds for 10 gtts/mL solution set).
Place a piece of tape over the catheter hub.
Make a small (kink free) loop in the IV tubing and place a second piece of tape over the first (piece of tape) to secure the loop.
Place a third piece of tape over the IV tubing above the site.
Ensure that the IV is properly secured and infusing properly.
Ensure that all "sharps" are placed in the sharps container.