Knowledge is key to understanding vascular access best practices. Christie’s clinical team has put together some basics to provide a valuable resource for healthcare practitioners.
Essentials of Peripheral Venous Access
Performing venipuncture and starting peripheral intravenous (IV) infusions are among the most challenging clinical skills you will ever have to master. Not all nursing schools offer enough hands-on learning, and hospitals commonly provide only limited opportunities for supervised practice. Even for the experienced clinician, IV placement can prove challenging depending on the patient and their pathology. This special guide is meant to provide a resource for some recognized best practices in peripheral intravenous access.
Selecting a Vein for Peripheral Catheter Insertion
When choosing an appropriate vein for venipuncture, consider patient factors – such as:
- current primary and secondary medical diagnoses
- medical history
- age, weight, and body size
- activity level
- dominant hand
- condition of veins as they appear
- characteristics of infusates and medications prescribed
- anticipated duration of treatment (this requires good communication between prescriber and nurses)
If therapy is expected to last 6 or less days, a short peripheral catheter may be an appropriate selection. If therapy is to last more than 6 days, a peripherally inserted central catheter (PICC) line or midline catheter should be considered.
When the prescribed fluid and medications have a pH below 5 or above 9 and/or osmolarity greater than 600 Osm/liter, PICC line or other appropriate central vascular device should be considered.
When short peripheral catheters are to be used, venipuncture sites should be chosen on the distal area and work up the extremity. Subsequent venipunctures should not be made distal to a previous puncture site as fluid can leak into the subcutaneous tissue from this proximal site. The lateral surface of the wrist should be avoided for approximately 4-5 inches beginning just above the thumb as nerve injury can be a risk in this location.
Starting with the non-dominant hand on adults is a good place to begin your assessment; this allows for use of the dominant hand for routine activities of daily living. Older adults who have poor skin turgor with minimal subcutaneous tissue present more of a challenge, and the hand vessels are generally not optimal. In pediatric patients that have not started to walk, other site options include the feet or lower extremities. Scalp veins are sometimes used in young infants. VeinViewer vein illumination can be very helpful in these cases to choose a better target for cannulation.
Remember insertion of a short peripheral catheter in the antecubital fossa vessels restricts movement and has a higher risk of nerve injury. Use of large gauge peripheral catheters could easily impede blood flow around the catheter, increasing the risk of mechanical and chemical damage to the vein wall. Short term procedures, like contrast injection for CT radiology may require a large gauge; however, removal following the procedure will reduce the risk of complications.
Each catheter can only be used for one venipuncture attempt. If that attempt fails, a new catheter must be used.
VeinViewer technology can also provide valuable information regarding valves, bifurcations, and anomalies such as terminating vessels. These can be problem areas on any vein, in any area and on any patient. These anatomical challenges cannot be seen with the naked eye nor felt with palpation.
Choosing an Appropriate Short Peripheral Catheter Size
Over-the needle catheter are ideal choices for veins located in the hand and forearm. Below are examples of catheters from 24 gauge (most common in pediatrics) to 18 gauge (larger bore).
Choosing the right short peripheral catheter size depends on several variables. While 20 gauge is the most commonly used, most routine fluids and medications, even blood transfusions, can be safely infused through a 22 gauge in adults. Use of winged needles should be avoided for all types of infusions. Refer to your hospital guidelines about appropriate catheter sizes for the smallest gauge catheter capable of delivering prescribed infusion therapy.
Tips and Tricks to Help with Vein Distention
- Active warming – This can be extremely effective in vasodilating vessels and bringing them closer to the skin's surface. This can be achieved with simple aids such as a warmed blanket or heat pack.
- Tourniquet technique – Apply a tourniquet 4-6" (10-15cm) above the area to be assessed. Do not place a tourniquet on the upper arm when assessing the hand and lower arm.
- Gentle tapping can vasodilate the vein and help with assessment; however, rough tapping or slapping can damage vasculature.
Complications Associated with Venous Access
- Hematomas most often occur when the vein wall has been pierced, commonly called a "blown" vessel. This occurs when the catheter goes into the vein but continues through the back wall of the vessel.
- Infiltration generally occurs after an infusion has been running and the vein becomes irritated. A weakness in the vein wall can occur and allow fluid to exit the vein into the tissue. This can be damaging, especially if a vesicant is being administered.
- Phlebitis is inflammation of the vein wall. This will usually occur at, above or below the insertion site. Mechanical causes include large gauge sizes, inadequate catheter stabilization and use of insertion sites in areas of joint flexion. Signs and symptoms include redness and pain.
- Thrombophlebitis is the formation of a clot and vein wall irritation at, above or below the catheter insertion site. This may happen if the catheter is too large for the vessel and does not allow adequate blood flow around the catheter, when an area of joint flexion is used or when the catheter is not adequately stabilized. Additional causes include fluid and medications with irritating properties, e.g. high doses of potassium chloride or vancomycin. Signs and symptoms include pain, redness and a palpable venous cord.
- Nerve damage is less common but can occur when a catheter transects a nerve during insertion and from compression due to excessive fluid in the tissue. This fluid can come from and infiltration/extravasation, thrombophlebitis or a hematoma. If a patient complains of electrical shock-like pain, tingling, a "pins and needles" sensation, or numbness – remove the catheter immediately and choose another site. Avoid the palm side of the wrist as this area contains many superficial nerves, and it is extremely difficult to stabilize the joint.
Using Near-Infrared Light Devices to Enhance Visualization
No medical device alone can eliminate the potential complications of IV therapies, nor can a device ensure the vein is cannulated in one attempt. VeinViewer technology can provide a level of assessment information that is not available to the naked eye alone or sense of palpation. VeinViewer can help guide you to a vein that is the best for your particular patient.
VeinViewer uses harmless near-infrared (NIR) light, similar to the wave length of pulse oximetry. NIR light is projected onto the surface of the skin; hemoglobin absorbs the NIR and surrounding tissue disperses it. The depth of penetration of VeinViewer is up to 10 mm deep for peripheral veins and up to 15 mm deep for blood patterns, blood within and without of the vein. Depth of visualization is dependent on the anatomy and condition of each patient.
- Use VeinViewer to assess multiple areas, looking for the best access point to help ensure a successful procedure.
- Occluding, pushing the blood out of the vessel with a gentle rub and then removing the occlusion allowing natural refill, allows you to see how the vein behaves under the surface of the skin. Your assessment should determine: is the vein pliable, does blood flow through the vessel readily, are there any valves in the area you plan to cannulate. This information can help guide you to the best possible vein and provides you additional assessment abilities that would not be possible with the naked eye alone.
- During placement of the catheter, use VeinViewer to help detect occurrences that might cause you to change your technique, such as a rolling vein. These issues can be addressed through anchoring of the vein by pulling the skin taunt distal to the planned venipuncture site. This step is key to successful venous cannulation. Should a hematoma occur, VeinViewer can show you this as it happens; at which point, the catheter must be removed and a different location chosen.
- After placement of the IV, use VeinViewer to help assess patency. Flushing of saline and visualization of the blood column dispersing can give you indication if the IV is flowing as it should. You can also perform the same assessment each time you check the patient's IV. Carefully assess the infusing fluid and medications before flushing. Flushing while infusing some medications could result in a dangerous dose of medication being delivered too quickly.
Remember nothing is superior to your common sense and clinical assessment of the vein. VeinViewer is an adjunct imaging tool to provide you with additional assessment information so you can make the best venipuncture decision.
For additional clinical education opportunities contact a Christie expert today by calling 877 SEE VEIN.