The size and type of catheter are determined by urgency of need and patient size, age, and vasculature. Blood should flow easily around the catheter after insertion. Larger diameter catheters are used for administering significant volume, colloid solutions, or blood or blood products, whereas smaller diameter catheters are used for routine vascular access. The smallest size and shortest length catheter that will deliver the prescribed therapy should be selected to decrease the potential for developing phlebitis. Catheters that are too large for a vessel can impede flow around the catheter and cause damage to the surrounding vessel wall. Catheters used for peripheral access include a straight catheter-over-needle design (Figure 10-2) and a butterfly or winged catheter (Figure 10-3). Catheters over needles are ideal for aggressive fluid replacement but can present problems with stabilization, particularly in distal veins of the hand. Winged catheters are easily inserted and can be stabilized with minimal effort; however, these catheters are not ideal for rapid fluid replacement. Their availability in smaller sizes increases their usefulness for pediatric and older adult patients. Unfortunately, they may be more uncomfortable than other catheters. Dual-lumen peripheral catheters must be flushed before insertion to activate a hydrolytic lubricant on the outside of the catheter. Intravenous catheters with safety features such as self-capping needles and retracting needles are readily available to decrease the health care worker’s potential exposure to bloodborne pathogens.

Aseptic technique is essential to protect the patient from infection during intravenous catheter insertion. Gloves should be worn for site preparation and catheter insertion; additional precautions are required for central line insertion. The selected insertion site should have adequate circulation and be free of infection. Peripheral veins in hands and arms are the first choice for intravenous access. Other sites include veins of the lower extremities or the external jugular veins. The external jugular vein is accessible in most patients but requires turning the patient’s neck for access. Lowering the patient’s head distends the vein and decreases risk for air embolism during insertion. Use of the external jugular vein is not recommended for patients with suspected neck injury. Use of the internal jugular vein is contraindicated in these patients.

After an extremity site is selected, a tourniquet is placed proximally to distend vessels for easy insertion (Figure 10-4, A). Because veins may be more prominent in older adult patients, a tourniquet may not be required. Tourniquets may actually rupture vessels because of increased pressure in fragile veins. Gently tapping or rubbing vessels below the tourniquet increases vessel size by dilation. When vessels are not easily visualized or palpated, applying warm towels over the vein for 5 minutes causes vasodilation and can facilitate catheter insertion (Figure 10-4, B).

Skin preparation begins with initial cleansing using a 2% chlorhexidine-based solution. ¹ Alcohol or povidone-iodine (Betadine) solution may be substituted if necessary. The solution is applied directly over the insertion site in a back-and-forth motion. Allow the antiseptic solution to air-dry on the selected site before catheter insertion.

Local anesthesia is not routinely used for catheter insertion when time is an issue. However, after site preparation, lidocaine 1% may be injected at the insertion site for immediate anesthetic effect. A topical anesthetic (EMLA, LMX-4) can be applied over the insertion site as an alternative to injection if time allows—depending on the agent used, 30 to 60 minutes is required to achieve an anesthetic effect. Vapocoolant sprays may also be used to decrease the discomfort associated with catheter insertion, depending on institutional protocol.

After the site is prepared, the catheter is inserted by stabilizing the vein to prevent movement during puncture. With the needle bevel up, skin is punctured using the smallest angle possible between skin and needle (Figure 10-5). Veins may be entered on the top or side. The catheter and needle are advanced slowly until blood flashes into the catheter, then the catheter is advanced over the needle into the vein. The tourniquet is removed, and intravenous tubing is connected. One-way valves are recommended to prevent bleeding from the catheter during subsequent tubing changes. If fluid therapy is not required, catheters may be capped with a one-way valve and sterile cover. The catheter and tubing should be secured with tape according to hospital policy; however, tape should never be applied directly over the insertion site. A sterile, transparent, semipermeable dressing is recommended for application over the insertion site. Sites should be labeled with the date, time, catheter size, and initials of the person inserting the catheter.

The subclavian, internal jugular, and cephalic veins are used for short- and long-term vascular access. Short-term central venous access is indicated when peripheral access cannot be obtained or when the patient’s condition requires hemodynamic monitoring. Long-term vascular access is indicated for prolonged intravenous therapy, total parenteral nutrition, extended antibiotic therapy, or therapy with caustic drugs such as vancomycin, and in patients with debilitating diseases such as cancer or acquired immune deficiency syndrome. To decrease the patient’s risk for developing a catheter-related infection, sterile surgical technique should be employed to insert these devices: the person inserting the line and the nurse assisting should be wearing sterile gloves and gown, mask, and cap with the patient draped from head to toe. In the ED, establishing central venous access is usually an emergent procedure that uses the subclavian or jugular veins. Figure 10-6 illustrates subclavian vein cannulization. Complications related to initial insertion include infection, hematoma, pneumothorax, and air embolism. The femoral vein located medial to the femoral artery may also be used for access to central circulation in some patients (Figure 10-7). The femoral vein is an excellent choice in cardiac arrest because cardiac compressions can continue during insertion. Access via the femoral vein also provides an opportunity for hemodynamic pressure monitoring. Complications associated with femoral vein access include hematoma and infection. Femoral sites should always be considered contaminated and replaced as soon as adequate alternative access can be obtained.

Most central venous access catheters are made of silicone or polyurethane and have a radiopaque strip. Silicone is less thrombogenic than other materials and becomes pliable with moisture. Disadvantages of silicone include migration of the catheter tip and inability to withdraw blood over time as the catheter softens and collapses inward. Single-lumen and multiple-lumen catheters are available. Awareness of access ports and indications for each lumen is critical for appropriate management. The proximal lumen, which can be used for medication and blood component administration, can also be accessed for blood collection after infusates have been stopped for one full minute. ⁵ The distal port, which is generally larger, can be used to administer high-volume or viscous fluids, colloids, and medications. Some catheters have additional ports, which should be utilized according to manufacturer recommendations.

Patients may come to the ED with nonemergent, long-term access central lines in place. These include catheters that may be peripherally inserted, tunneled externally, or totally implanted (Table 10-1). Long catheters inserted peripherally in the cephalic or basilic vein can be left in place for 6 to 8 weeks. ² The safe length of time to leave these catheters in place is steadily increasing. The midline catheter (MLC) ends just inside the subclavian vein, whereas a peripherally inserted central catheter (PICC) extends as far as the superior vena cava (Figure 10-8). Complications include infection and catheter migration. Tunneled external lines (Figure 10-9) and implanted ports (Figure 10-10) are used for long-term access, usually over months or even years. Implanted infusion ports are placed in the subcutaneous tissue, usually below the right clavicle or inner aspect of the upper arm. A catheter is threaded from the port through a large vein and into the superior vena cava. Only noncoring (e.g., Huber) needles are used to access the port. These catheters and ports should be flushed after each use with saline and then heparin per hospital protocol.