Central venous line (CVL) placement is a bedside procedure in which a catheter is threaded into one of the body’s large veins, with the tip ideally resting near the junction of the superior vena cava and the right atrium. Clinicians perform millions of these insertions each year for patients who need long-term intravenous medications, concentrated nutrition solutions, rapid fluid resuscitation, or hemodynamic monitoring. The procedure has become substantially safer over the past two decades thanks to real-time ultrasound guidance, standardized infection-prevention bundles, and simulation-based training, yet it still carries meaningful risks that vary with the insertion site, the patient’s clotting status, and the operator’s experience.
Why a Central Line Is Needed
A central venous catheter is typically considered when peripheral IV access has failed or when the treatment itself demands a larger, more durable line. Medications that are highly concentrated, caustic to small veins, or that constrict blood vessels can damage peripheral veins quickly, so they require delivery into a high-flow central vessel where they are diluted almost instantly.1PubMed. Peripheral and central venous access Total parenteral nutrition, certain chemotherapy drugs, vasopressors like norepinephrine, and prolonged antibiotic courses are common reasons a care team will request central access. In emergency departments and ICUs, the need for rapid, large-bore access during resuscitation or the inability to find a usable arm vein often drives the decision as well.2Journal of the Association for Vascular Access. Indications for Peripheral, Midline, and Central Catheters: Summary of the Michigan Appropriateness Guide for Intravenous Catheters Recommendations
Choosing the Insertion Site
Three veins serve as the primary targets for central line placement: the internal jugular vein in the neck, the subclavian vein beneath the collarbone, and the femoral vein in the groin. Each comes with a distinct risk profile, and the choice involves balancing infection risk, thrombosis risk, and the chance of a mechanical complication during insertion.
A large randomized trial published in the New England Journal of Medicine compared all three sites head to head. The subclavian site came out ahead, with roughly 1.5 complications per 1,000 catheter-days compared with about 3.6 for the jugular and 4.6 for the femoral. The femoral site carried more than triple the complication risk of the subclavian site, while the jugular site roughly doubled it.3PubMed. Intravascular Complications of Central Venous Catheterization by Insertion Site An earlier trial specifically comparing the femoral and subclavian sites found the femoral route was associated with far higher rates of both infection and blood clots: overall infectious complications ran about 20% femoral versus roughly 5% subclavian, and thrombosis was similarly lopsided.4JAMA. Complications of Femoral and Subclavian Venous Catheterization in Critically Ill Patients: A Randomized Controlled Trial
The subclavian site is not without drawbacks. It carries the highest risk of pneumothorax, a complication in which air leaks into the space around the lung. A large multicenter cohort study found that subclavian catheterization had nearly six times the odds of pneumothorax compared with other sites, and that limited operator experience independently increased the risk as well.5British Journal of Anaesthesia. Mechanical complications after central venous catheterisation in the ultrasound-guided era: a prospective multicentre cohort study In practice, the internal jugular vein has become the most commonly used site for non-emergency insertions because it offers a good balance: lower infection and thrombosis rates than the femoral vein, a lower pneumothorax risk than the subclavian, and excellent visibility under ultrasound.
How Ultrasound Changed the Procedure
Before portable ultrasound became widely available, clinicians located veins by relying on surface landmarks: the angle of the jaw, the clavicle, the pulse of nearby arteries. That approach worked much of the time, but it also meant more needle passes, more accidental arterial punctures, and more failed attempts. The shift to real-time ultrasound guidance has been one of the biggest safety gains in central line placement.
A Cochrane review pooling data from more than two dozen trials found that two-dimensional ultrasound cut total complications by about 71% for internal jugular catheterization, reduced accidental arterial punctures by roughly 72%, and raised the chance of first-attempt success by 57%. Even the average time to successful cannulation dropped by about half a minute.6PubMed Central. Ultrasound guidance versus anatomical landmarks for internal jugular vein catheterization A systematic review and meta-analysis of complication rates across sites confirmed the pattern: ultrasound was associated with an 80% lower rate of arterial puncture and a 75% lower rate of pneumothorax compared with the landmark technique.7PubMed Central. Complication Rates of Central Venous Catheters: A Systematic Review and Meta-Analysis
The evidence is somewhat less dramatic for the subclavian site specifically. One academic emergency department study found that ultrasound guidance improved overall success rates for subclavian catheterization but did not significantly lower complication rates, and the ultrasound group actually took longer to complete the procedure.8PubMed. Ultrasound-Guided vs. Landmark Method for Subclavian Vein Catheterization in an Academic Emergency Department The subclavian vein sits behind the clavicle, which creates an acoustic shadow that makes real-time needle visualization harder than at the jugular site. Still, most guidelines now recommend ultrasound for all central line insertions whenever it is available.
Where the Catheter Tip Should Sit
Getting the catheter into the vein is only half the job. The tip needs to end up in the right spot, typically at or near the cavoatrial junction where the superior vena cava meets the right atrium.9PubMed. Optimal Prediction of the Central Venous Catheter Insertion Depth Targeting the Cavoatrial Junction A tip that is too high, sitting in a smaller vessel like the brachiocephalic vein or even curled up into the jugular, increases the risk of vessel wall erosion, medication irritation, and inaccurate pressure readings. For long-term catheters, a tip positioned too far from the junction is also more likely to migrate out of position with arm movement or changes in body posture.10Korean Journal of Anesthesiology. Determination of optimal tip position of peripherally inserted central catheters using electrocardiography: a retrospective study
The traditional method for confirming tip position is a post-procedure chest X-ray. Bedside ultrasound has emerged as a faster alternative. One study found that ultrasound assessment took a median of four minutes, while getting a chest X-ray took a median of 29 minutes.11PubMed Central. Comparison between ultrasound and chest X-ray to confirm central venous catheter tip position However, ultrasound had a lower specificity for detecting malposition in that study, meaning it occasionally missed a catheter that was in the wrong place. For now, many institutions use ultrasound as a rapid screen and reserve chest X-ray for cases where there is uncertainty or where clinical suspicion for pneumothorax is high. Some centers also use intracavitary electrocardiography, tracking changes in the heart’s electrical signal as the guidewire or catheter approaches the right atrium, as another way to confirm positioning without radiation.12Korean Journal of Anesthesiology. Determination of optimal tip position of peripherally inserted central catheters using electrocardiography: a retrospective study
Managing Bleeding Risk in Patients With Low Platelets
Many patients who need central lines also have abnormal clotting: cancer patients on chemotherapy often have low platelet counts, and critically ill patients frequently have disordered coagulation. There has been a longstanding habit of transfusing platelets or fresh frozen plasma before insertion to “correct” the numbers. The evidence for this practice is surprisingly weak.
A systematic review found that the severity of coagulopathy did not reliably predict bleeding, and no study demonstrated a clear benefit from prophylactic transfusion. Observational data suggested that correction may not be necessary for platelet counts above roughly 20,000 per microliter or an INR up to 3.0.13PubMed. Central venous catheter placement in coagulopathic patients: risk factors and incidence of bleeding complications A study in critically ill patients with severe thrombocytopenia reached a similar conclusion: after adjusting for other factors, the presence of additional coagulopathy made no measurable difference in bleeding risk during ultrasound-guided placement.14PubMed Central. Contribution of Coagulopathy on the Risk of Bleeding After Central Venous Catheter Placement in Critically Ill Thrombocytopenic Patients
A more recent randomized trial in thrombocytopenic patients did find that platelet transfusion before insertion reduced overall catheter-related bleeding, roughly 5% in the transfusion group versus about 12% in the group that received no platelets. However, when the researchers looked at the more clinically significant grade 3 or 4 bleeds, the difference narrowed and was no longer statistically significant.15PubMed. Platelet Transfusion before CVC Placement in Patients with Thrombocytopenia The takeaway for patients and families: the team may decide not to transfuse before the procedure, and that decision is backed by a reasonable body of evidence, especially when ultrasound guidance is used.
Preventing Bloodstream Infections
Central line-associated bloodstream infections, often abbreviated CLABSIs, were once among the most feared complications of having a central line. They add days to hospital stays, drive up costs, and carry real mortality risk. The good news is that infection rates have plummeted in institutions that have adopted structured prevention bundles, which are small sets of evidence-based practices performed together during insertion and maintenance.
A meta-analysis in The Lancet Infectious Diseases found that implementing these bundles cut infection rates from a median of about 6.4 per 1,000 catheter-days to around 2.5, a reduction of more than half.16The Lancet Infectious Diseases. Effectiveness of prevention (insertion and maintenance) bundles for catheter-associated bloodstream infections in intensive care units: a systematic review and meta-analysis A single-center study that tracked outcomes over nine years saw even more dramatic improvement, with rates falling from 2.6 per 1,000 catheter-days before the bundle to 0.46 afterward.17PubMed Central. The Effectiveness of Bundle Applications in the Prevention of Central Line-associated Bloodstream Infections: Nine Years of Observation
The typical insertion bundle includes hand hygiene, full sterile barrier precautions (gown, gloves, cap, mask, and a large drape), skin antisepsis with chlorhexidine, avoiding the femoral site when possible, and removing the catheter as soon as it is no longer needed. Maintenance bundles add ongoing practices like regular dressing changes, scrubbing the catheter hub before each access, and using disinfection caps on unused ports.18PubMed Central. Prevention of Catheter-Related Infections and Complications: A Narrative Literature Review of Vascular Care and Maintenance Antimicrobial-coated catheters, impregnated with either chlorhexidine-silver sulfadiazine or antibiotics, have also been shown to lower infection rates. A network meta-analysis found that both types of coated catheters reduced catheter-related bloodstream infections compared with standard uncoated lines, though the benefit was most consistent in ICU settings.19PubMed Central. Effectiveness of antimicrobial-coated central venous catheters for preventing catheter-related blood-stream infections with the implementation of bundles: a systematic review and network meta-analysis A Cochrane review confirmed roughly a 2% absolute reduction in definite catheter-related bloodstream infections with impregnated catheters, alongside a 9% lower rate of bacterial colonization on the catheter itself.20Cochrane Database of Systematic Reviews. Central venous catheter coating with antiseptics or antibiotics for reducing catheter-related infections in adults
Thrombosis and Catheter-Related Clots
Any foreign object sitting inside a blood vessel can trigger clot formation. With central lines, the catheter rubs against the vessel wall and disrupts normal blood flow, creating conditions that favor thrombosis. The risk varies with the type and location of the catheter. Known risk factors include left-sided insertion, a large catheter relative to the vein diameter, and longer dwell times.21PubMed. Central venous catheter-related thrombosis in children and adults
Peripherally inserted central catheters, or PICCs, deserve special mention here. PICCs are threaded through an arm vein and advanced until the tip reaches the central circulation. They are popular because they can be placed at the bedside by specially trained nurses, avoid the risks of neck or groin insertion, and are convenient for outpatient use. However, they carry a higher thrombosis risk than conventional central lines. A meta-analysis found that PICCs were associated with roughly 2.5 to 3 times the odds of thrombosis compared with centrally inserted catheters, both in ICU patients and in cancer patients.22PubMed. Peripherally Inserted Central Catheter lines for Intensive Care Unit and onco-hematologic patients: A systematic review and meta-analysis A study in a neurological ICU found a symptomatic thrombosis rate of about 8.4% with PICCs versus 1.4% with conventional central lines.23PubMed. Comparison of catheter-related large vein thrombosis in centrally inserted versus peripherally inserted central venous lines in the neurological intensive care unit For ICU patients who are expected to have a short hospital stay, a conventional CVC is often preferred for this reason. PICCs still make sense for patients who need weeks of IV antibiotics at home or ongoing chemotherapy, where their convenience outweighs the added clot risk.
Among the factors that influence PICC-related thrombosis, catheter diameter and number of lumens matter. Triple-lumen PICCs and catheters with a larger outer diameter were both associated with higher thrombosis rates in one ICU study.24PubMed Central. Risk factors for peripherally inserted central catheter line-related deep venous thrombosis in critically ill intensive care unit patients Choosing the smallest catheter that will meet the patient’s needs is a simple way to lower the risk.
Emergency Versus Elective Placement
There is a common assumption that central lines placed in chaotic emergency settings carry higher infection rates than those placed under controlled conditions. The data on this are more reassuring than you might expect. A retrospective study of trauma patients found no significant difference in CLABSI rates between lines placed emergently in the emergency department and those placed elsewhere in the hospital.25PubMed Central. Trauma Emergency Department Placed Central Lines for Trauma Patients: A Retrospective Case-Control Study on Central Line–Associated Blood Stream Infection Risk From Central Lines Placed Emergently in the Emergency Department Another study comparing ED-placed and ICU-placed lines found infection rates of about 2.5 and 4.6 per 1,000 catheter-days, respectively, with no statistically significant difference.26PubMed. Incidence of central line associated bloodstream infection following central venous catheter placement in the emergency department
That said, not every setting has the same adherence to sterile technique under pressure. An older ICU study did find higher catheter-related infection rates in lines placed during emergency procedures compared with elective ones, with roughly 43% of emergency-placed lines showing signs of infection versus about 18% of elective lines.27PubMed Central. Central venous catheter-related bloodstream infections in the intensive care unit The discrepancy likely reflects differences in institutional protocols and whether full barrier precautions are consistently maintained during urgent situations. Where teams have adopted standardized insertion bundles that are followed regardless of urgency, the emergency-versus-elective gap appears to close.
How Training Affects Outcomes
Operator skill matters more than many patients realize. Simulation-based training programs have become standard in residency curricula, and the research suggests they translate into measurable improvements at the bedside. In one study, residents who completed simulation-based mastery learning required fewer needle passes during real ICU procedures compared with traditionally trained residents.28PubMed. Use of simulation-based mastery learning to improve the quality of central venous catheter placement in a medical intensive care unit Fewer needle passes means less tissue trauma, less pain, and a lower chance of hitting an artery or causing a pneumothorax.
A more recent multi-institutional study found that simulation-based curricula nearly doubled residents’ self-reported comfort with CVC insertion, from about 42% to 81%.29PubMed Central. Simulation-based Central Venous Catheter Insertion Training Increases Comfort Amongst Residents Comfort may sound like a soft measure, but a clinician who feels confident and unhurried is more likely to follow each step of the sterile protocol, use ultrasound properly, and make deliberate needle advances rather than rushed ones. The British Journal of Anaesthesia cohort study mentioned earlier found limited operator experience to be an independent predictor of pneumothorax, reinforcing the idea that training is not just about confidence but about measurable safety.30British Journal of Anaesthesia. Mechanical complications after central venous catheterisation in the ultrasound-guided era: a prospective multicentre cohort study
Pain Management During the Procedure
Central line placement is done under local anesthesia in most awake patients. The injection of local anesthetic itself can sting, and some patients feel pressure or discomfort during needle advancement and catheter threading. A study comparing different local anesthetic techniques found that lidocaine delivered by needle-free injection or standard infiltration both outperformed a topical anesthetic cream, with average patient pain scores around 2.4 to 2.6 out of 10 versus about 4.2 for the cream.31PubMed Central. Pain and efficacy of local anesthetics for central venous access
For patients who are particularly anxious or who have had painful prior procedures, some centers offer light procedural sedation. A randomized trial found that low-dose remifentanil, a short-acting opioid given intravenously, cut patients’ global pain scores in half compared with placebo, without causing serious side effects.32PubMed. Remifentanil for Procedural Sedation and Analgesia in Central Venous Catheter Insertion: A Randomized, Controlled Trial In ICU patients who are already sedated and mechanically ventilated, pain from central line placement is often managed by adjusting existing sedation. Either way, the procedure should not be agonizing. If you are awake and told you need a central line, it is entirely reasonable to ask what pain control will be used.
Central Lines in Newborns
Neonatal central venous access is a different world from adult practice. The veins are tiny, the patients cannot cooperate, and the catheter types differ. Newborns most commonly receive either an umbilical venous catheter, threaded through the stump of the umbilical cord in the first days of life, or a PICC placed in an arm or leg vein. A cross-sectional study of neonates in Saudi Arabia found that PICCs had higher overall complication rates than umbilical venous catheters, including more phlebitis, occlusion, and leakage. Non-elective removal occurred in about 32% of PICC cases versus 23% of umbilical catheter cases. However, umbilical catheters had more malposition events, frequently migrating to the liver.33BMJ Open. Central venous catheter insertion profile and complications among neonates in Saudi Arabia: a cross-sectional study The choice between the two depends on the baby’s age, clinical needs, and expected duration of IV therapy.
What Happens When the Line Comes Out
Removal of a central line might seem straightforward, but it carries its own risk, most notably air embolism. When the catheter is pulled from a large central vein, the tract left behind can briefly act as a direct conduit between the atmosphere and the bloodstream. If the patient inhales at the wrong moment, air can be sucked into the vein and travel to the heart or lungs. Standard precautions include placing the patient flat or slightly head-down, having them hold their breath or hum during removal, and applying an occlusive dressing immediately afterward. Researchers have explored modified techniques that further reduce this risk, including suturing over the tract during removal, with promising results in small retrospective studies.34J. Vasc. Bras.. Prevention of air embolism related to central venous catheter removal: an integrative review Air embolism during removal is rare when proper technique is followed, but it can be fatal when it occurs, which is why even a routine line removal demands attention to the steps.35PubMed Central. Air Embolism: Practical Tips for Prevention and Treatment