Peripheral Site Selection
While any vein in an extremity is considered a peripheral vein, certain veins have more desirable qualities than others. These veins are preferred by Paramedics for venous access.
Figure 27-13 Engineered safety catheter.
The following text describes the steps taken to obtain intravenous access.
While it is easy to see some surface veins, deeper and less visible veins may be more desirable. These deeper veins are anchored in subcutaneous fat, helping to stabilize them and prevent them from moving, or rolling, away from the needle. They are also generally larger in diameter. To distend these veins, making them easier to either visualize or palpate, a venous tourniquet is applied.23 A venous tourniquet is made of a soft, wide material which can apply a constricting force around the circumference of a limb. Examples of materials used for a tourniquet include leather straps, blood pressure cuffs, and rubber strips. A popular tourniquet is a length of penrose drain. A penrose drain is a tubular rubber hose which lies flat and provides a wide band of compression.
The tourniquet is typically placed around the arm, either above the elbow or above the wrist, and then tied into a slip knot, with the knot on the medial surface. Next, the distal pulse is palpated. A distal arterial pulse should remain palpable at all times and the limb should not become cyanotic. If the pulse is obliterated and/or the patient’s limb becomes cyanotic, then the tourniquet should be immediately removed. As a general rule, a venous tourniquet should not remain in place for more than a few minutes. In most cases, the Paramedic can accomplish all of the tasks needed to obtain venous access within that time period.
After a moment, the veins will start to distend and become more visible. Starting proximal and moving distal, the Paramedic should be able to identify the following veins: axillary, basilic, cephalic, and dorsal arch.
The axillary vein (Figure 27-14) runs from the shoulder over the biceps toward the elbow. This vein is more prominent in thin people and those who do considerable lifting for a living. The advantage of the axillary vein is two-fold. One is its proximity to the trunk. This is particularly advantageous when administering certain medications, such as adenosine. The axillary vein also has fewer valves than other more distal veins, making it easier to cannulate.
Figure 27-14 Gaining access in the axillary vein.
Figure 27-15 Gaining IV access in a potentially violent patient using the basilic vein.
The next vein, the basilic vein, runs down the dorsal aspect of the arm and ends at the medial wrist. The basilic vein is particularly advantageous when trying to start an IV on a confused or combative patient. The Paramedic would position himself at the head of the stretcher and pull the patient’s arm toward him. With the arm bent at the elbow, the arm can essentially be locked into position, permitting unimpeded access to the vein (Figure 27-15).
The vein running down the forearm, immediately opposite the basilic, is the cephalic vein. The cephalic vein runs down the lateral aspect of the forearm and terminates proximal to the thumb. The distal portion of the cephalic vein is most commonly used by Paramedics (Figure 27-16).
Figure 27-16 Gaining IV access in the cephalic vein.
To stabilize the cephalic vein, the Paramedic takes the patient’s hand as if shaking hands. With a firm grasp of the hand, the Paramedic palpates for a void at the distal forearm called the autonomic sniff box. The cephalic vein generally lies within the autonomic sniff box.
The most distal peripheral veins of the arm are part of the dorsal venous plexus, a group of veins that originate between each digit and from an arch across the dorsum of the hand. While the veins of the dorsal arch are generally the most visible, making them appear attractive to Paramedics, they contain a number of valves and tend to be somewhat torturous. If an IV is to be attempted here, a short 1-inch needle is preferred.
To start an IV in the dorsal arch of the hand, the Paramedic should first grasp the fingers and bend them inward toward the palm. With the fingers stabilized by the thumb, the Paramedic can proceed with insertion of the IV (Figure 27-17). Generally, the plane of the insertion of the needle is sharper as the veins of the hand are more superficial.
Although the external jugular vein (EJV), strictly speaking, is not a peripheral venous access, it is treated as such by many Paramedics because it can be easily visualized, readily palpated, and more importantly, it is compressible if extravasation should occur. Because of its location, the actual method of preparing the site for insertion of an IV device is slightly different. To identify the external jugular vein, the patient should be placed in a supine position to maximize venous return.24,25
While it would be impractical to apply a tourniquet around a patient’s neck, it is possible to compress (tamponade) the vein by applying a thumb to the distal portion of the external jugular vein just superior to the clavicle, at the mid-clavicular line. By turning the patient’s head away from the intended insertion side, the external jugular vein should be clearly visible. The EJV starts proximal to the angle of the jaw and inferior to the ear and then takes a relatively straight course toward the mid-clavicular line (Figure 27-18).
Figure 27-17 Gaining IV access in the dorsal arch. 
Figure 27-18 Gaining IV access in the external jugular vein.
The saphenous vein, often overlooked by Paramedics, provides an excellent point for venous access when the upper extremities are not available, perhaps due to burns or fractures, for example.26, 27 The long saphenous vein, one of two superficial veins in the leg, is the longest vein in the body, stretching from the groin to the foot. The short saphenous vein extends from the top of the foot, proximal to the outer or lateral malleolus, then runs alongside it, then crosses the Achilles tendon to end in the middle of the back of the knee and connects with the popliteal vein. Both saphenous veins communicate with deeper veins via bridging veins called perforators, which literally perforate the fascia of the muscle bundles to connect with the deeper veins. This unique aspect of the saphenous vein permits drugs given via this route to gain rapid access to the larger veins of the legs.
Some patients, particularly patients with diabetes, have poor circulation in the lower extremities. This poor circulation tends to retard healing of a wound. Therefore, Paramedics generally avoid starting an IV in the foot if the patient is known to have diabetes or poor circulation in the extremities (peripheral vascular insufficiency). Other signs of poor circulation in the feet include misshapen toenails and distal cyanosis of the toes when dependent.
STREET SMART
Knowing the exact peripheral venous anatomy is advantageous to the Paramedic confronted with a patient who is in cardiovascular collapse or arrest when the veins are not visible. By starting distal and working proximal, the Paramedic can make a series of calculated "blind sticks" in an effort to secure venous access for the administration of potentially life-saving drugs.
The basilic vein, the cephalic vein, and several bridging veins between the basilic and the cephalic veins, including the cubital vein, exist in the area of the anterior elbow, called the antecubital fossa (AC). Some Paramedics prefer to obtain venous access in this area, perhaps because of their experience of having observed test blood drawn (phlebotomy) from the area. The decision to attempt an IV access in the antecubital fossa should be made only after careful considerations of the risks. The antecubital fossa is a part of the elbow joint. Intravenous access obtained proximate to the elbow joint risks being dislodged if the patient should suddenly bend the joint or move the arm. To prevent this occurrence, it may be necessary to restrict the patient’s movements by securing the arm to a rigid armboard.
To complicate matters, the median nerve, the brachial artery, the radial bone, the ulna bone, the humerus bone, the basilic vein, and the cephalic vein, plus numerous muscles, tendons, and ligaments, cross through or terminate in the elbow.28, 29 Accidental infiltration of an IV that contains hyperosmolar or caustic chemicals (e.g., dextrose 50% or dopamine) for example, can create tissue ischemia and necrosis of structures within the elbow, possibly leading to permanent disability.
STREET SMART
During a cardiac arrest, the veins of the antecubital fossa may represent the Paramedic’s best opportunity to obtain IV access during the emergency. The difficulty arises when the Paramedic has to distinguish an artery from a vein. To avoid accidental arterial puncture, Paramedics routinely attempt the IV access on the lateral side, opposite of the location of the brachial artery on the medial side of the antecubital fossa.
Difficult Venous Access
Patients who are elderly, who have undergone chemotherapy, who have a poor nutritional status, or who are obese, plus a number of other medical conditions, may have a poverty of visible peripheral veins. These patients present a special challenge to the Paramedic.
To improve venous filling of the peripheral veins, it is important to maintain the limb in the dependent position, below the heart. Elevating the limb to "eye level," instead of kneeling next to the patient, will quickly drain the limb and the venous distention will be gone.
Some Paramedics advocate applying a warm wrap around the dependent limb approximately 10 minutes before the IV access is to be attempted. This technique is acceptable, but caution is advised when applying heat to the skin of the elderly patient or those with impaired sensation. Unintentional burns can occur due to the application of heat pads.
Indirect (tangential) lighting from a flashlight held to the side of the patient’s arm may also improve venous visibility. However, the best results are obtained when the Paramedic has an understanding of peripheral venous anatomy combined with gentle palpation of the forearm to detect deeper veins. When a vein is palpated under the skin, it should rebound (i.e., feel spongy). If the Paramedic is unsure if the structure palpated is a tendon or vein, then she should ask the patient to move the extremity through a slight range of motion while palpating. Tendons will move with the motion whereas the vein will not.
Every vein should be palpated to ensure that the vein is not an artery. In low output states (i.e., hypoperfusion), it may be difficult to distinguish an artery from a vein. To complicate matters, some arteries, nerves, and veins run together as a bundle deeper in the extremity and proximal to bone. In the circumstance that an artery is accidentally cannulated, blood may rapidly back up the administration set and pulsations may be visible in the column of blood. In those cases, the catheter should be removed immediately and a direct pressure applied to the arterial puncture site (Skill 27-2).
Venous Site Precautions
During an emergency, any venous access is acceptable, however, when time permits, and under special circumstances, the Paramedic should carefully consider the alternative IV access sites. For example, if the patient is suspected of having an acute myocardial infarction, then attempts to obtain IV access in the right antecubital fossa are reserved until last. The right AC is a preferred access site for interventional cardiac procedures, such as angiocatheterization and angioplasty.
As a courtesy to the patient, it is preferred that the IV site selected be on the nondominant arm. This allows the patient greater flexibility and movement, including the ability to attend to the activities of daily living (ADL) such as signing admission papers. To quickly ascertain the nondominant hand, the Paramedic should look for a wristwatch. In most cases, the patient will wear the watch on the nondominant hand. If the watch must be removed to obtain an IV access or to prevent damage to the watch, the Paramedic should make a notation on the patient care report (PCR) including a notation as to whom the watch was given.
Several medical conditions, such as long bone fractures, burns, and breast cancer, preclude the Paramedic from starting an IV on an affected limb, except under extraordinary circumstances. The Paramedic should make careful note of these conditions and avoid starting an IV on the affected limb if at all possible.
The presence of an armboard to stabilize a fracture may be seen as an invitation to start an IV on the immobilized limb. However, the circulation surrounding a bone fracture may be disrupted and infiltration of intravenous solutions into the injury may further complicate the patient’s care. Therefore, IVs are generally not started on injured limbs.
Burns represent another relative contraindication to an IV access. Whenever alternative access sites are available, the Paramedic is encouraged to use them. However, if the patient has sustained massive burns, and no other sites are available, some burn authorities advocate starting the IV through the burn tissue.
When an intravenous solution is infused, it remains in the circulation until a number of factors, such as decreased colloidal osmotic pressure, combine to create a mismatch between the actual tonicity of the patient’s blood and the tonicity of the intravenous solution and cause it to shift into the third space, the interstitial fluid. For example, it has been estimated that NSS only remains in the bloodstream for about 20 to 30 minutes before it "leaks" into the tissues.30, 31 Thus intravenous infusions can create an increase in interstitial fluid. Normally, the body’s lymphatic system would help to drain the excess interstitial fluid out of the tissues, and back in the central circulation, bringing the body’s fluids back into balance. However, patients with breast cancer frequently undergo a procedure called an axillary lymph node dissection, as a part of a diagnostic or therapeutic intervention for the cancer. These patients may no longer be able to drain the excess fluid from the affected limb, and a condition called lymphedema sets into the affected limb. Lymphedema, unchecked, can cause swelling of the limb, compression of nerves, and paralysis. For this reason, Paramedics avoid starting an IV on the same side as the axillary lymph node dissection.32-34 Frequently, these patients have been educated to warn Paramedics about starting an IV, or taking blood pressures, on the affected side, and many wear medical alert bracelets warning that the patient has lymphedema. If the patient is unconscious and has had a mastectomy, or is wearing a compression stocking on the arm, or there is surgical scar in the axilla, then the Paramedic should assume that an axillary lymph node dissection has taken place and choose another site for venous access.
