Peripheral intravenous access. The placement of an IV or intravenous catheter is an important procedure that all health care providers should master. An IV is often needed for rapid venous access during a cardiac arrest or trauma, administration of fluid, blood products, and nutrition, as well as administration of medication, anesthetics, and contrast medium.
In general, peripheral IV should not be placed in the extremities with burns, infections, or thrombophlebitis. They should also be avoided in the extremity with peripheral edema, particularly in patients with a history of radical mastectomy and axillary dissection because of the inability of the lymphatic drainage system to handle extravasated fluid or medication.
To minimize the risk of infection or thrombosis, IVs should be avoided in the extremity with shunts or fistulas. Although the equipment needed to place an IV depends on the clinical situation, the following are generally needed-- gloves, IV set of tubing and bag, catheter over needle intravenous units.
Although the size of the IV used depends on the clinical need, number 18 or 20 gauge IV catheters are commonly used in adult populations and number 22 gauge for pediatric patients. Alcohol swabs or iodine prep, adhesive tape and clear adhesive dressing, gauze, tourniquet. Except for specific situations, ultrasonography is generally not needed for peripheral IV placement.
After obtaining informed consent, the patient should be sitting comfortably or preferably lying supine. To minimize risk of blood exposure to health care providers, safety precautions in placing IVs must be applied. The patient should be kept warm, as veins are generally vasodialted in warm extremities. There are a number of commercial topical anesthesia products which are designed to alleviate discomfort during IV placement.
While they are effective, optimal analgesia generally requires application 30 to 60 minutes prior to the procedure. They may be appropriate for pediatric population, but they may not be practical in most adult patients. Most IVs can be placed without topical anesthesia, particularly in emergency situations. However, for elected intravenous catheter placement, it is our preference to prepare the skin with a topical anesthesia using 1% lidocaine with a 27 gauge needle injected as a small intradermal wheal.
In general, the selection of a vein should depend upon the availability of the extremity, the size and access of the vein, and the IV catheter use. While a large, straight vein is appealing, it is our preference to use the junction of veins as a puncture site in the middle of the y, which tethers the vein and provides a degree of immobilization during the placement of the catheter.
Although veins near the ankle are large and may be useful for emergency vascular access, IV access in feet and ankles are suboptimal, particularly for long term use. The cephalic, basilic, and median cubital veins in the antecubital fossa are large and are suitable for large bore IVs, particularly in emergency situations. However, with the IV in place, mobility of the arm is somewhat restricted.
In general, the cephalic vein at the wrist and veins on the dorsal aspect of the hand are the common sites for IV placement. While a blood pressure cuff may provide better venous stasis, a tourniquet is generally adequate. The tourniquet should not be applied too tightly, as it impedes arterial flow and subsequent venous filling. The tourniquet should first be placed under the arm with the two ends brought together and crossing each other.
To allow easy release of the tourniquet, a loop is created by pulling the overlying end tight and then tucking it below the underlying end. The skin of the chosen site should be cleansed with either iodine or alcohol and allowed to dry before the infiltration of lidocaine. With the slight traction of the skin and with the bevel of the needle facing up, the needle is inserted slowly through the skin and into the vein at an angle no more than 30 degrees.
A flashback of blood into the chamber can be seen when the needle punctures the vein. To ensure that the catheter is inside the vein, the needle should be advanced three to four millimeters further into the vein before advancing the catheter over the needle. This is probably one of the most important steps in IV placement. Release the tourniquet, and compress the tip of the intravenous catheter for withdrawing the needle from the catheter.
Connect the IV set tubing to the catheter. The catheter must be secured. While some suggest the use of a small strip of tape placed under the hub of the catheter, folded over the catheter like a bow, we prefer the use of clear polyurethane dressings such as an Opsite or Tegaderm to secure the catheter along with taping. If an IV does not have a constant infusion flowing through the tubing, anticoagulant flush solutions are used in catheters to prevent thrombi and fibrin deposits.
A commonly used solution is 5 milliliters of saline with 10 units per milliliter of heparin. The most common complications are failed IV placement, hematoma and bruising, as well as pain. To minimize shearing off and tearing of the catheter, reinsertion of the needle through the catheter should be avoided during IV placement. Other complications are rare and are usually associated with drug and fluid administrations as well as the duration of the IV catheter left in place.
These include superficial thrombophlebitis, infection, nerve damage, and air embolism. Patients who are obese, cold, dehydrated, and adenitis, as well as patients who have had recent chemotherapy, usually present significant challenges in IV placement. The following steps may make IV placement more successful. Careful inspection of the extremities for an appropriate site without rushing is critical.
Proper preparation of the patient and equipment must precede all IV placements. The patients should keep their extremities warm prior to IV placement. If the patient's extremity is cold, vasodilation of the peripheral veins can be encouraged with the heat pack. It is our preference to warm a 100 milliliter IV saline fluid bag in a microwave oven for 20 to 30 seconds.
It is then applied to the site of an IV placement and wrapped with a towel for about five minutes. To minimize damage to the skin, the IV fluid bag should be warm but not scolding hot when applied to the site. Vasodilation can be achieved with the application of 2% nitroglycerin ointment for two to three minutes to the site of a patient with small veins. Asking the patient to open and close his or her fist, gentle tapping of the vein, or to lowering the arm below the level of the heart right.
Successful IV placement in deep veins of the arm using ultrasound has recently been suggested. However, the role of the ultrasound-guided technique for peripheral IV access has yet to be defined. Safety in placing IVs cannot be overemphasized. To prevent inadvertent needle injuries and transmission of infections to health care providers, newer IV catheters with protective sleeves that encase the sharp needle as it is retracted from the catheter have been introduced.
While these devices have different designs, the principle in placement of these catheters remains the same. One of the most common mistakes in placing an IV is the failure to advance the needle and catheter unit three to four millimeters further into the vein before advancing the catheter over the needle when a flashback of blood into the chamber is seen. This is a crucial step for successful IV placement.
In summary, peripheral IV access is a clinical skill that all health care providers should master. Successful placement of an IV requires meticulous preparation of the patient and equipment, knowledge of anatomy, patience, as well as skill.