INTRODUCTION — Insertion of a central venous catheter in a human was first reported in 1929. A technique that facilitates catheter placement into lumens and body cavities was subsequently introduced by Sven-Ivar Seldinger in 1953 [1]. Insertion of a central venous catheter using the Seldinger technique revolutionized medicine by allowing safe and reliable venous access [2].

Central venous catheters are common among critically ill patients. In the United States in 2014, over 15 million catheter-days/year were recorded in the intensive care unit alone [3]. Multilumen central venous catheters have become ubiquitous in the intensive care unit. New catheter designs, standardization of insertion techniques, use of ultrasound guidance, and improvements in central line care have reduced complication rates.

Central venous access is a commonly performed procedure, with approximately 8 percent of hospitalized patients requiring central venous access. More than five million central venous catheters are inserted in the United States each year [4,5].

Central venous access also facilitates other interventions and device insertions, including the following: pulmonary artery catheter, plasmapheresis catheter, hemodialysis catheter, extracorporeal life support cannula, inferior vena cava filter, and intracardiac pacing wire and defibrillator leads. The central venous access site and techniques by which access is achieved depend upon the indication for placement, patient vascular anatomy, and other patient-related factors.

The indications for central venous access, types of central catheters, catheter selection, site selection, and general issues of preparation and placement will be reviewed here. The role of catheters and devices for monitoring cardiac parameters or administering chemotherapy or parenteral nutrition are discussed in separate topic reviews.

The general principles of ultrasound-guided placement and placement of jugular, subclavian, and femoral catheters; issues specific to these anatomic sites; routine maintenance and care of catheters and port devices; and complications of central venous catheters and related devices are covered elsewhere. (See "Principles of ultrasound-guided venous access" and "Placement of jugular venous catheters" and "Placement of subclavian venous catheters" and "Placement of femoral venous catheters" and "Overview of complications of central venous catheters and their prevention in adults".)

CENTRAL VENOUS ACCESS DEVICES — A central venous access device is defined as a catheter inserted into a venous great vessel, which includes the superior vena cava, inferior vena cava, internal jugular vein, subclavian vein, iliac vein, common femoral vein, or brachiocephalic vein. Access is typically obtained at different anatomic sites by percutaneous puncture to cannulate the vein, with ultrasound guidance. (See "Principles of ultrasound-guided venous access" and 'Cannulation site' below and "Central venous access devices and approach to device and site selection in adults", section on 'Access site'.)

A wide range of central venous catheters and devices are available and are classified based on duration of catheter use (algorithm 1) (ie, dwell time; short-term, mid-term, long-term), type of insertion (ie, central, peripheral), location of insertion (eg, jugular, subclavian, femoral, brachial), number of lumens (ie, single, double, triple), as well as whether the catheter is implanted or not, and to what extent (eg, tunneled, totally implanted [ie, port]) (figure 1). The basic features of the various types of catheters and the way these features influence catheter selection are discussed separately. (See "Central venous access devices and approach to device and site selection in adults".)

Several other medical devices require central venous access for placement, usually with an introducer sheath.

INDICATIONS — Indications for the placement of central catheters include [6-9]:

●Inadequate peripheral venous access (unable to obtain, or complex infusion regimen).

●Peripherally incompatible infusions – Long-term intermittent or continuous administration of medications such as vasopressors, certain chemotherapy agents, and parenteral nutrition are typically administered into a central vein as they can cause vein inflammation (phlebitis) when given through a peripheral intravenous catheter.

●Hemodynamic monitoring – Central venous access permits measurement of central venous pressure, venous oxyhemoglobin saturation (ScvO₂), and cardiac parameters (via pulmonary artery catheter).

●Extracorporeal therapies – Large-bore venous access is required to support high-volume flow required for many extracorporeal therapies, including renal replacement therapy (ie, hemodialysis) and plasmapheresis.

●Venous access is also needed for venous interventions as well as the placement of other medical devices, including:

•Vena cava filters (image 1) (see "Placement of vena cava filters and their complications")

•Venous thrombolytic therapy/venous angioplasty/venous stenting (see "Endovenous intervention for iliocaval venous obstruction")

•Pulmonary artery catheters (figure 2) (see "Pulmonary artery catheters: Insertion technique in adults")

•Pacemakers/defibrillators (figure 3) (see "Temporary cardiac pacing" and "Permanent cardiac pacing: Overview of devices and indications" and "Implantable cardioverter-defibrillators: Overview of indications, components, and functions")

Relative contraindications — Contraindications to central venous catheterization are relative and depend upon the urgency and alternatives for venous access.

Coagulopathy and/or thrombocytopenia — Moderate-to-severe coagulopathy is a relative contraindication to central venous catheterization, although major bleeding is uncommon. A systematic review of central line placement in coagulopathic patients documented a bleeding incidence of 0 to 32 percent, with major bleeding complicating in 0.8 percent. Importantly, the risk of bleeding was not predicted by the severity of coagulopathy [10].

The need for urgent and emergency venous access may require cannulation in spite of coagulopathy, and the safety of standard and large-bore nontunneled catheter placement in this circumstance has been documented [11-15]. In general, nontunneled catheterization at sites that are easy to monitor for bleeding is preferred in patients with coagulopathy. The subclavian approach is preferably avoided due to inability to effectively monitor or compress the venipuncture site, unless an alternative site is not suitable. (See "Central venous access devices and approach to device and site selection in adults", section on 'Benefits/risk for specific sites'.)

For patients with severe coagulopathy who require immediate central venous access, we recommend ultrasound-guided cannulation performed by an experienced provider [16]. Ultrasound guidance decreases the number of attempts required for successful cannulation and reduces complication rates, including bleeding. (See 'Use of ultrasound' below.)

The platelet count, international normalized ratio (INR), and partial thromboplastin time thresholds for which central venous catheterization can safely be performed remain unclear. Thrombocytopenia appears to pose a greater risk compared with prolonged clotting times [17,18]. In spite of common concern and practice, there is limited evidence supporting routine correction of coagulopathy prior to central venous cannulation [10,15,19,20]. Retrospective studies suggest that no preprocedure reversal is warranted for platelet count >20 x 10⁹/L and INR <3 [10]. For severe coagulopathy (eg, platelet count <20 x 10⁹/L and INR >3), we advocate consideration of administration of a preprocedure blood product (eg, platelets, fresh frozen plasma) when time allows and based on the clinical decision that the benefit of preprocedure replacement outweighs the risk. The indications for correcting coagulopathy in patients undergoing invasive procedures and dosing are discussed in detail elsewhere. (See "Platelet transfusion: Indications, ordering, and associated risks", section on 'Preparation for an invasive procedure' and "Clinical use of plasma components", section on 'Overview of indications'.)

Site-specific considerations — Cannulation is generally avoided at sites with anatomic distortion or other indwelling intravascular hardware, such as a pacemaker or hemodialysis catheter. Contaminated or potentially contaminated sites such as local skin infection or proximity to a wound, burn, or tracheostomy should be avoided. Vascular injury proximal to the insertion site represents another relative contraindication. Relative contraindications for specific sites are discussed below. (See 'Cannulation site' below and "Central venous access devices and approach to device and site selection in adults", section on 'Site comparisons'.)

CANNULATION SITE — The most appropriate site for central venous cannulation should be individualized based on the clinical situation. Operator skill, ultrasound availability and findings, patient anatomy (eg, recognizable landmarks, known venous occlusion, presence of lymphedema), risks associated with placement (eg, coagulopathy, pulmonary disease), and access needs (eg, patient needs and duration of catheter use) are important considerations [21-25]. Specific veins (jugular, subclavian, femoral) and access approaches have inherent advantages and disadvantages. These issues and site selection are reviewed separately. (See "Central venous access devices and approach to device and site selection in adults", section on 'Access site' and "Central catheters for acute and chronic hemodialysis access and their management", section on 'Access site considerations'.)

Specific access site considerations are reviewed separately.

●Jugular venous catheters (see "Placement of jugular venous catheters", section on 'Specific approaches')

●Subclavian venous catheters (see "Placement of subclavian venous catheters", section on 'Approaches to the subclavian vein')

●Femoral venous catheters (see "Placement of femoral venous catheters", section on 'Femoral vein cannulation')

●Peripherally inserted central catheters

The anatomic site chosen for central catheter placement influences the risk for and type of complications, including catheter-associated infection [26]. Risk associated with catheters may be minimized with experienced clinician insertion of catheters, use of ultrasound guidance, strict sterile technique, and trained nursing staff catheter care [27]. We follow the United States Centers for Disease Control and Prevention (CDC) guidelines and generally avoid the femoral site unless there are outstanding issues with cannulation of alternative sites. (See "Overview of complications of central venous catheters and their prevention in adults".)

PREPARATION — Nontunneled percutaneous central catheters are usually placed at the bedside, while tunneled catheters and port devices can be placed in an interventional suite or operating room using fluoroscopic guidance. The equipment needed for central venous catheterization is given in the table (table 1).

Informed consent — Informed consent should be obtained for any central venous catheter, including those placed percutaneously or requiring an incision (eg, port). Consent for vascular access is implied for emergency situations.

The procedure plan, including indications, benefits, and potential complications of the procedure (eg, pneumothorax), should be discussed with the patient and/or legal guardian. The potential need to perform a secondary procedure, such as chest tube placement to evacuate a pneumothorax, should also be conveyed. (See "Informed procedural consent".)

Patient monitoring — All patients should be monitored during central venous access procedures, including continuous cardiac rhythm and pulse oximetry. Supplemental oxygen should be immediately available, and, for some patients, it may be prudent to administer oxygen by nasal cannula prior to covering the patient's head with any drapes.

Patient positioning — Once the access sites and approach are chosen, the patient is positioned to optimize patient and proceduralist comfort and cardiopulmonary stability. While preparing and draping the patient, a supine position is adequate. The bed or table should be placed at a height that allows the operator to remain comfortable throughout the procedure. The patient is positioned to maximize the diameter of the vein during the vascular access procedure, which depends upon the site selected. Although Trendelenburg position facilitates venous filling for jugular and subclavian access and may reduce the risk of venous air embolism [28-32], critically ill and patients with obesity not tolerate this position. Patients at risk for respiratory compromise may require anesthesia with a controlled airway to safely place a central catheter or device. (See "Anesthesia for the patient with obesity", section on 'Patient positioning'.)

Sterile technique — To reduce infectious complications, all central venous access procedures, including emergency procedures, should be performed in a location that permits the use of aseptic technique. This includes sterile drapes large enough to cover the entire patient, sterile cover for ultrasound probe, surgical antiseptic hand wash, long-sleeved sterile gown, surgical mask, gloves, and head covering [7,33-38].

Site preparation — Hair should be clipped from the access site prior to skin preparation. Clipping is preferred to shaving [39]. When jugular or subclavian access is planned, preparing the skin of the neck and chest bilaterally facilitates access to alternative sites in the event that the planned venous site cannot be cannulated. (See "Overview of control measures for prevention of surgical site infection in adults", section on 'Infection control'.)

Skin antisepsis — Use of antiseptic solution for skin disinfection at the catheter insertion site reduces the risk of infection. A chlorhexidine-alcohol skin antiseptic solution should be applied to the access site and allowed to dry prior to draping the patient [40]. Chlorhexidine-based solutions (>0.5% chlorhexidine preparation with alcohol) are superior to both aqueous and alcohol-based povidone-iodine in reducing the risk for catheter colonization and catheter-related bloodstream infection (CR-BSI) [40-42]. An additional preparation kit may be required for those that contain only iodine solutions. If there is a contraindication to chlorhexidine, tincture of iodine, an iodophor, or 70% alcohol can be used as alternatives [43].

In a meta-analysis of eight trials including 4143 catheter insertions, disinfection with chlorhexidine was associated with a 50 percent reduction in CR-BSI compared with aqueous povidone-iodine [41]. Subsequently, in a trial including 2349 patients (5159 catheters) who were randomly assigned to chlorhexidine-alcohol or povidone iodine-alcohol prior to catheter insertion, the incidence of catheter-related infection was significantly lower with chlorhexidine-alcohol (0.28 versus 1.77 per 1000 catheter-days; hazard ratio 0.15, 95% CI 0.05-0.41) [40].

No role for systemic antimicrobial prophylaxis — Antimicrobial prophylaxis prior to percutaneous central venous catheter placement is not standard practice. A meta-analysis comparing antibiotics versus no antibiotics for totally implanted venous access devices also showed no significant difference in infection rate [44].

Analgesia and sedation — Patient movement may preclude successful cannulation, and, in a conscious patient, every effort should be taken to ensure patient comfort and cooperation. This is accomplished using local anesthesia (topical, infiltrated) and sedation, if needed. For patients who are awake and anxious, minimal sedation can be achieved with a low-dose, short-acting benzodiazepine to help the patient relax. Deeper sedation may be needed in uncooperative children or adults. (See "Procedural sedation in children outside of the operating room" and "Procedural sedation in adults outside the operating room".)

Topical anesthetics are helpful and effective when time permits, particularly in children. The algorithm provides guidance regarding selection of an appropriate topical agent in children (algorithm 2). (See "Clinical use of topical anesthetics in children".)

Infiltration of the skin overlying the access site is usually accomplished with lidocaine (1 or 2%). Lidocaine with epinephrine is generally unnecessary but may be useful during the placement of tunneled catheters to decrease bleeding from the subcutaneous tunnel. (See "Subcutaneous infiltration of local anesthetics".)

Subcutaneous infiltration of local anesthetics is helpful, but overzealous infiltration can distort landmarks, increase the depth of penetration needed to access the vessel, and cause vein compression, making needle access more difficult. Avoid injection of air into the subcutaneous tissues, as it will interfere with ultrasound transmission. The use of ultrasound and safe administration of local anesthesia are reviewed separately. (See 'Use of ultrasound' below and "Subcutaneous infiltration of local anesthetics".)

For tunneled catheters or port placement, infiltration of a longer-acting local anesthetic (eg, bupivacaine) into the tract or subcutaneous pocket limits postoperative pain for up to 12 hours. (See "Management of acute perioperative pain", section on 'Preventive analgesia'.)

USE OF ULTRASOUND

Precannulation vein assessment — We recommend the use of ultrasound to guide central venous cannulation when it is available and practical (see 'Real-time ultrasound guidance' below). Before cannulation, routine bedside ultrasound by the provider placing the access can evaluate venous patency and aid in selecting the most appropriate site of access and is particularly useful in patients who have a history of prior instrumentation or deep vein thrombosis in the region of the proposed access site [45]. (See "Principles of ultrasound-guided venous access", section on 'Global use of ultrasound' and "Catheter-related upper extremity venous thrombosis in adults", section on 'Duplex ultrasonography'.)

Preprocedure ultrasound also identifies anatomic variations, which is particularly useful for reducing trauma associated with line placement in children. In a study of 140 children, anatomic variations occurred in approximately 7 percent [46].

Real-time ultrasound guidance — Familiarity with ultrasound-guided access is a critical aspect for the practitioner performing central venous catheterization. Real-time dynamic ultrasound (ie, imaging during needle placement) reduces time to venous cannulation and the risk of complications. The principles of ultrasound and techniques to identify venous structures for venous access are discussed in detail elsewhere. (See "Principles of ultrasound-guided venous access".)

When ultrasound is not available, landmark techniques are used to guide access. (See "Placement of jugular venous catheters" and "Placement of subclavian venous catheters" and "Placement of femoral venous catheters".)

Detection of complications — Proper use of ultrasound aims to reduce major complications. Ultrasound also assists with early detection of arterial and venous guidewire malposition and identification of procedurally related pneumothorax [47,48]. An important caveat to these studies is that accuracy of diagnosis was dependent upon ultrasound operator skill. (See 'Confirmation of catheter tip position' below and "Bedside pleural ultrasonography: Equipment, technique, and the identification of pleural effusion and pneumothorax".)

GENERAL TECHNIQUE — The placement of central catheters and other venous devices follows similar principles. Specific details of central catheter placement for the various anatomic locations (jugular, subclavian, femoral) and other devices are discussed elsewhere. (See "Placement of jugular venous catheters" and "Placement of subclavian venous catheters" and "Placement of femoral venous catheters" and 'Other devices' below.)

Nontunneled central catheters — The general method for placing nontunneled central catheters is as follows (see "Principles of ultrasound-guided venous access", section on 'Preparation'):

●Obtain the equipment and devices needed for catheter placement (picture 1 and table 1).

●Prepare (consent, sedation) and position the patient. Confirm location and patency of the target vein with preprocedure ultrasound, if available.

●Pause for a procedural time-out to verify the procedure, site, and technique.

●Using sterile technique, prepare the skin and drape the patient.

●Identify pertinent anatomic landmarks, even if ultrasound is used. Reconfirm the vein with ultrasound.

●Infiltrate the skin with local anesthetic (eg, 1% lidocaine, bupivacaine). (See "Subcutaneous infiltration of local anesthetics".)

●Cannulate the vein using dynamic ultrasound imaging via standard introducer needle, micropuncture needle (picture 2), or angiocatheter.

●Insert the guidewire into the vein through the access needle or angiocatheter. Confirm the intravenous guidewire via ultrasound.

•Maintain awareness of guidewire depth during insertion. In the absence of fluoroscopy, the guidewire should only be inserted just beyond the anticipated catheter depth, avoiding intracardiac advancement.

•Maintain telemetry monitoring to identify arrhythmias induced by the guidewire. If an arrythmia occurs, pull back on the wire until it resolves.

●Remove the needle or angiocatheter while controlling the guidewire.

●Make a single small stab incision in the skin at the puncture site adjacent to the guidewire.

●Advance the tissue dilator over the guidewire into the vein, taking care to control the guidewire, then remove the tissue dilator.

●Thread the catheter over the guidewire, taking care to control the guidewire.

●Remove the guidewire, taking care to control the catheter.

●Sequentially aspirate blood from each access hub and flush with saline to ensure a functioning catheter.

●Secure the catheter into place and dress the site using sterile technique.

●Confirm the position of the tip of the catheter with chest radiography (for jugular and subclavian approaches only).

Other devices — The basic principles for placing other central venous devices are like those outlined above. However, a venous sheath is typically placed via the same guidewire technique first, and the catheter, device, or pacemaker lead is introduced through it. A brief description of the placement of these devices compared with standard percutaneous central catheters is given below.

Venous sheath placement — The introducer sheath is a combined tissue dilator and sheath assembly with a side port for intravenous access. Once the guidewire is in place and the vessel is dilated, the tissue dilator and sheath are advanced over the guidewire together. The tissue dilator and guidewire are then removed, leaving the sheath in place. Once the sheath is in place, the side port is aspirated and irrigated to check function, and the sheath is secured to the skin at its exit site.

Tunneled catheters — Venous access for tunneled catheters is obtained in a manner like nontunneled catheters. Tunneled catheters and catheters associated with subcutaneous port devices are typically inserted using fluoroscopic guidance. The exit site of the catheter on the skin is chosen, which determines the length of catheter that will be needed for proper catheter tip positioning. For some tunneled catheters, the excess length of catheter provided is trimmed before the catheter is tunneled; for others, it can be trimmed afterward. Other types of catheters come in fixed lengths (eg, dialysis catheters), and the position of the exit site is chosen to accommodate the predetermined length of the catheter. For subclavian and jugular tunneled catheters, the exit site on the chest wall should be located below the midclavicle in a position that does not interfere with clothing or upper extremity mobility.

Percutaneous access is performed as outlined above. Once the guidewire is in position, the skin at the guidewire exit site is incised to accommodate at least the diameter of the catheter. Following administration of local anesthesia to the catheter exit site and planned subcutaneous tunnel, an incision is made at the planned catheter exit site. A tunneling device is usually included in the catheter kit and is attached to the distal catheter lumen orifice (ie, catheter tip lumen hole rather than more proximal port). The catheter is advanced subcutaneously from the catheter exit site to the guidewire exit site (antegrade), and the tunneler is removed. Some catheters will need to be tunneled retrograde. Care is taken to ensure that the tunnel provides a gentle curve in the catheter from the catheter exit site to the guidewire site. Acute angulation may lead to poor flow rates and catheter malfunction. After dilating the vein, the tissue dilator/sheath combination is placed over the wire using fluoroscopic guidance. The tissue dilator is removed, and the catheter is advanced through the sheath and the sheath peeled away. The position of the tip of the catheter is checked and adjusted, as needed. The cuff of the tunneled catheter is ideally located at the exit site of the catheter. The catheter is sutured to the skin to prevent malposition until the cuff is incorporated in the subcutaneous tissue.

Subcutaneous ports — Venous access is obtained in a standard fashion. Once the guidewire is in place, local anesthetic is administered into the skin and subcutaneous tissue in the region of the planned pocket. An incision is made through the skin and using electrocautery, the pocket is created to accommodate the device by undermining the subcutaneous tissue to the level of the fascia. Prior to placing the port, its function should be checked by inserting a needle and irrigating with saline, which should flow freely through the port hub. The device is placed into the pocket, and the size of the pocket and orientation of the device is adjusted as needed.

Once the pocket is completed, the catheter is tunneled from the pocket to the guidewire exit site, if needed (eg, jugular venous access). Care is taken to avoid catheter angulation, which will lead to mechanical dysfunction. After dilating the vein, the tissue dilator/sheath combination is placed over the wire. The tissue dilator is removed, the catheter is placed through the sheath, and the sheath is peeled away. The catheter is positioned and adjusted as needed. The excess catheter is trimmed and attached to the hub of the port device, which is placed into the pocket and sutured into place. Placing sutures at three points of fixation into fascial tissue is important to prevent port rotation, which can transpose the access hub away from the skin surface, making access difficult. The subcutaneous tissues and skin are sutured closed. Prior to dressing the wound, the port should be accessed through the skin, and the port aspirated and irrigated to confirm its proper functioning. Ports are typically packed with heparinized saline according to the manufacturer's recommendation if they are not accessed for immediate use.

Dressings — A sterile dressing is placed overlying the exit site of the catheter as delineated by local hospital practice or policy.

The type of dressing may influence the rate of catheter infection [49]. Either sterile gauze or a sterile, transparent, semipermeable dressing can be used. Transparent dressings are widely used. They are more breathable, allow monitoring for fluid accumulation and local signs of inflammation, and improve nursing workflow. Other types of dressings may be appropriate depending on the clinical circumstances.

The catheter site dressing should be replaced if the dressing becomes damp, loosened, or visibly soiled. If the patient is diaphoretic or if the site is bleeding or oozing, a gauze dressing may be used.

Dressings on short-term central access sites should be replaced every two days (gauze dressings) or every seven days (transparent dressings). Transparent dressings on tunneled sites should be replaced no more than once per week (unless the dressing is soiled or loose), until the insertion site has healed [50].

Chlorhexidine exit site sponge — Placement of a chlorhexidine gluconate-impregnated sponge (CHGIS) at the catheter exit site may reduce catheter-related infections. In general, we use chlorhexidine-impregnated dressings to protect the insertion site of short-term, nontunneled central venous catheters (CVCs) [51,52], although standard local hospital practice or policy may dictate specific care.

Among 1636 patients with CVCs or arterial catheters, use of a dressing incorporating a CHGIS compared with standard dressings was associated with a decrease in catheter-related bloodstream infection (CR-BSI); the rates decreased from 1.3 to 0.4 per 1000 catheter-days (hazard ratio 0.39) [53]. Catheter colonization rates were similar at the three-day and the seven-day dressing change. It is important to note that the observed incidence of infection may have been influenced by several factors, including the inclusion of arterial catheters (46 percent) and the exclusion of antimicrobial-impregnated catheters. In a smaller randomized controlled trial of intensive care unit patients requiring a CVC for more than three days, use of CHGIS had no effect on catheter colonization rates, nonbacteremic catheter-related infections, or CR-BSIs, although the low number of events limited the power of the study [54].

Use of a novel silver-plated dressing for CVCs may be more effective for prevention of infection than CHGIS dressings [55]. However, others have described development of bacterial resistance with silver-impregnation dressings [56].

Topical antimicrobials — Application of topical antimicrobial ointment at the catheter exit site has not consistently demonstrated a reduced rate of infection but is associated with increased rates of antimicrobial resistance and Candida colonization [57-59]. (See "Central catheters for acute and chronic hemodialysis access and their management", section on 'Exit-site antimicrobial agents'.)

CONFIRMATION OF CATHETER TIP POSITION — Catheter tip positioning can be confirmed with one or more of the following methods: chest radiography, fluoroscopy, ultrasound, transesophageal echocardiography (typically intraoperative), and intracavitary electrocardiography (IC-ECG) [48,60-68]. Chest radiography and fluoroscopy are the most used methods in the United States.

●Radiography – In nonemergency situations, a postprocedure chest radiograph is recommended to confirm catheter course and tip position prior to use of jugular and subclavian catheters. Femoral catheters do not require radiologic confirmation of position. The need for routine radiography confirmation of apparently uncomplicated right internal jugular catheter placement has been questioned [62,64,65].

●Ultrasound and echocardiography – Alternative imaging modalities to radiography to confirm catheter tip position include ultrasound and transesophageal echocardiography, which are particularly useful in critical care settings and in the operating room. The increasing use of real-time ultrasound to guide venous access has led to its use as a method to assess for proper positioning of the catheter as well as identification of postprocedure pneumothorax [69-71]. A meta-analysis that pooled 20 studies showed sensitivity of 88 percent and specificity of 99 percent for ultrasound detection of pneumothorax, compared with 52 and 100 percent for chest radiography [70,72]. (See "Clinical presentation and diagnosis of pneumothorax", section on 'Pleural ultrasonography'.)

●Intacavitary electrocardiography – IC-ECG is another technique that relies on detection of intracardiac P wave patterns obtained during catheter positioning. The rationale for this approach is that the sinoatrial node is located at the junction of the right atrium and superior vena cava (cavoatrial junction). Thus, mapping the catheter tip to the SA node internally identifies the biologically correct catheter tip position. Following catheter insertion, an electromagnetic guidewire is threaded through an introducer needle and connected to an electrocardiograph monitor lead. On the IC-ECG tracing:

●A normally shaped P wave identifies the mid-to-upper superior vena cava.

●The widest P wave indicates the central catheter tip is at the superior vena cava-right atrium junction.

●A biphasic P wave identifies the location of the right atrium.

●Superimposition of the intracavitary ECG with a surface ECG at the point of maximal P wave deflection indicates appropriate positioning of the catheter tip.

Several reviews in pediatric and hemodialysis populations have confirmed the utility of this technique [73-76]. In the largest review of over 1000 cases, the technique was successfully applied in 98 percent. The presence of preexisting cardiac arrhythmias that affect P wave generation and propagation (eg, atrial flutter and fibrillation) constitutes a main technique limitation, and in these cases, IC-ECG may not be helpful [76]. A meta-analysis and large registry review have found improved tip positioning for IC-ECG compared with plain radiography for placement of peripherally inserted central catheters [77,78].

Optimal catheter tip positioning — The optimal positioning of the catheter tip depends on the specific access site. Catheter tip confirmation and positioning, management of malpositioned catheters, and management of inadvertent arterial insertion are discussed separately for the common access sites. (See "Placement of jugular venous catheters", section on 'Confirmation of jugular catheter position' and "Placement of femoral venous catheters", section on 'Confirmation of femoral catheter position' and "Placement of subclavian venous catheters", section on 'Confirmation of subclavian catheter position'.)

In general, catheters function well with the tip situated in any major vein. However, suboptimal tip position may be related to delayed complications. As an example, catheter tip position within the subclavian vein is associated with thrombosis. If a catheter is malpositioned within the venous system, it may be used under emergency circumstances but should be repositioned when feasible. In contrast, inadvertent placement of a catheter into the arterial system mandates immediate attention [79]. (See "Vascular complications of central venous access and their management in adults".)

CATHETER MANAGEMENT — Management of central venous catheters is aimed at preventing catheter infection and thrombosis and handling mechanical complications.

Proper catheter maintenance involves minimizing the duration of temporary catheter access, performing routine catheter site inspections, periodically changing the catheter site dressing, using aseptic technique when handling catheters, and changing the catheter, when indicated. Catheter site management and catheter care are discussed elsewhere. (See "Intravascular catheter-related infection: Prevention", section on 'Site care'.)

Catheter lumen thrombosis may be reduced using catheter lock solutions, and when thrombosis occurs, thrombolytic therapy may restore lumen patency. Thrombosis related to mechanical problems often requires catheter replacement. These issues are discussed elsewhere. (See "Catheter-related upper extremity venous thrombosis in adults", section on 'Thrombosis prevention' and "Catheter-related upper extremity venous thrombosis in adults", section on 'Catheter management' and "Lock therapy for intravascular non-hemodialysis catheter-related infection".)

CATHETER REMOVAL — Proper removal of central venous catheters is important to avoid complications such as bleeding and air embolism. Air may be entrained via the catheter or catheter tract during insertion, use, and removal. Patient positioning and appropriate catheter management and removal techniques prevent this complication. Prompt needle and catheter lumen occlusion are standard practice [28,29]. Trendelenburg positioning and Valsalva maneuver (eg, asking the patient to hum) increase venous pressure and help minimize abrupt negative pressure swings from spontaneous breathing that are capable of entraining air via any open communication with the venous system [28,29]. Prior to central venous catheter insertion and removal, patients should be placed in the supine or Trendelenburg position, as tolerated. The catheter should be removed during exhalation, when intrathoracic pressure is greater than atmospheric pressure. Firm pressure should be applied for at least three minutes following removal, with subsequent placement of a temporary sterile pressure dressing.

COMPLICATIONS — The complications related to central venous access (table 2) are discussed separately. (See "Overview of complications of central venous catheters and their prevention in adults".)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Venous access".)

SUMMARY AND RECOMMENDATIONS

●Common indications for central venous access include inadequate intravenous access, medication and fluid administration, hemodynamic monitoring, and extracorporeal therapy (eg, hemodialysis, plasmapheresis). Central venous access is also used to facilitate insertion of vascular devices, including pulmonary artery catheters, pacemakers/defibrillators, inferior vena cava filters, and to perform venous interventions. (See 'Indications' above.)

●Central venous catheters can be inserted through the jugular, subclavian, or femoral veins, or via upper arm peripheral veins. The type of catheter and site chosen are often determined by the clinical scenario of the individual patient and provider preference. The optimal site is determined by operator experience, patient anatomy, and clinical circumstances. (See 'Cannulation site' above and "Central venous access devices and approach to device and site selection in adults", section on 'Access site'.)

●Moderate-to-severe coagulopathy (platelet count <20 x 10⁹/L and international normalized ratio [INR] >3) is a relative contraindication to central venous catheterization, with thrombocytopenia posing a greater risk than prolonged clotting time. The subclavian vein approach is preferably avoided in all patients, if an alternative access is available. (See 'Coagulopathy and/or thrombocytopenia' above.)

●Prior to the placement of central catheters, pre-cannulation ultrasound should be performed by the provider placing the access to evaluate venous patency and aid in selecting most appropriate site of access. (See 'Use of ultrasound' above and "Catheter-related upper extremity venous thrombosis in adults".)

●Ultrasound guidance is recommended and is particularly useful in pediatric venous access and in high-risk patients, such as those with coagulopathy. Real-time dynamic ultrasound guidance during vessel puncture reduces time to venous cannulation and the risk of complications. (See 'Use of ultrasound' above and "Principles of ultrasound-guided venous access", section on 'Summary and recommendations'.)

●Central venous catheterization is performed through a series of well-defined steps. Venous sheaths are placed in a similar manner. (See 'General technique' above.)

●Catheter tip positioning can be confirmed with one or more of the following methods: chest radiography, fluoroscopy, ultrasound, transesophageal echocardiography (typically intraoperative), and intracavitary electrocardiography (IC-ECG). Chest radiography is often used to confirm jugular and subclavian catheter placement prior to use in nonemergency situations. Femoral catheters do not require radiological confirmation of position. The need to confirm placement in all patients undergoing jugular venous access procedures is controversial. Periprocedural ultrasound or IC-ECG are alternative techniques to detect catheter malposition and pneumothorax. (See 'Confirmation of catheter tip position' above.)