The Art of the Central Line Introduction



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The Art of the Central Line


Introduction

Central venous access is required in 8% of hospitalized pts and >5 million central venous catheters are placed each year. This statistic shows the importance of learning this skill while in residency. A “Central line” implies that direct access to the central venous system (Superior/Inferior Vena Cava) has been obtained. This paper is meant to serve as a summary of all the data on central venous access and as a quick reference before central venous access is attempted (via summary page). The focus of this paper will predominantly be on the jugular access site as this is our preferred approach.


Catheter Insertion Site

The 3 large veins that are typically cannulated are the Internal Jugular, Subclavian, and Femoral. The preferred site currently by major organizations and critical care physicians is the Internal Jugular Vein. This is due to easy accessibility, ease of ultra-sound guidance in this area, lower failure rate with novice operators and overall low complication rates, and they are the preferred site for temporary hemo-dialysis. There have been studies comparing Subclavian versus IJ access. There appears to be lower infection rates in the subclavian, but these results have not been validated, as these were observational studies. The randomized trial that compared IJ to subclavian port access for cancer therapy found no sig differences in infection rates or mechanical complications. A well established, accepted detail is infection rates are highest in femoral access, then IJ ~ subclavian (in descending order). If femoral catheters have to be used, they should be removed as soon as possible to reduce catheter-associated complications. This means if a femoral line was placed in the E.R., it should be removed once in the ICU and replaced with an IJ. Pulmonary complications such as hemo and pneumothorax appear equivalent despite historic reports of higher rates with the subclavian approach, both being observed to be ~1%. However, it is anecdotal that subclavian incurs higher pneumothorax rates. Studies have also showed that IJ access is more preferable in cachectic pts and in pts with respiratory compromise. When all this data is reviewed, it is the recommendation that the IJ should be the preferred site unless the pt is in active CPR and peripheral IV access can’t be established.

With that being said, specific anatomic sites and cannulation approaches have inherent advantages and disadvantages. Therefore, each physician placing the central line may have different preferences. Below is a table showing advantages and disadvantages of the different catheter insertion sites.


Approach

Advantages

Disadvantages

Internal Jugular

Minimal risk of pneumothorax (especially with US guidance)
Head of table access
Procedure-related bleeding amendable to direct pressure
Lower failure rates with novice operators
Excellent target using US guidance

-Not ideal for prolonged access

-Risk of Carotid artery puncture

Uncomfortable

-Dressings and catheter difficult to maintain

-Thoracic duct injury possible on the left

-Poor landmarks in obese/edematous pts

-Vein prone to collapse with hypovolemia

-Difficult to access during emergencies when airway control is being established



Subclavian

Easier to maintain dressing
More comfort
Better landmarks in obese pts
Accessible when airway is being established

-Increased risk of pneumothorax

-Procedure related bleeding less amenable to direct pressure

-Decrease success with inexperienced operators

-Longer path from skin to vessel

-Catheter malposition more common

-Interference with chest compressions



Femoral

Rapid access with high success rates
Does not interfere with CPR
Does not interfere with intubation
No risk of pneumothorax

-Delayed circulation of drugs during CPR

-Prevents pt moving

-Difficult to keep site sterile

-Increased risk of illeo-femoral thrombosis



Access to sites with altered local anatomy, sites with multiple scars from prior access, and the presence of another central venous catheter or device, such a as pacer, or ICD, are associated with higher rates of access failure, malposition, dysrhythmia and other complications and thus are avoided. So if these things are present, another site needs to be chosen. If a pt has significant unilateral lung dz, use this side to minimize respiratory decompensation in the event of a procedure-related pneumothorax. Subclavian should not be accessed for hemodialysis catheters due to the risk of venous stenosis complicating subsequent hemodialysis access.
Indications


  1. Administration of noxious medications: vasopressors, chemotherapy, and Total Parenteral Nutrition (TPN) are given by central venous catheters b/c they can cause phlebitis when given through a peripheral IV catheter. These medicines are caustic to the vein and almost always lead to infiltration of a peripheral catheter.

  2. Hemodynamic monitoring: Central venous access allows measurement of the Central venous pressure (CVP) and central venous oxyhemoglobin saturation (important in the treatment of sepsis and the workup of acute respiratory failure). In fact, in the new guidelines on Sepsis Management termed “Surviving Sepsis” (see Wiki for the paper) part of the initial management is to maintain these patients CVP in the 8-12 mmHg range. A

  3. Plasmapharesis, apharesis, hemodialysis, and Renal replacement therapy (RRT)

  4. No or poor peripheral venous access

  5. Transvenous cardiac pacing

  6. IVC filter placement (Greenfield filter)


Contraindications

  1. Anatomic distortion (i.e. prior clavicular fracture, median sternototmy, neck surgery, or neck irradiation)

  2. Other indwelling vascular catheters (i.e. pacemaker, etc)

  3. Numerous past access to the site

  4. Coagulopathy: this is a RELATIVE contraindication to central venous catheterization, although significant bleeding is uncommon in the IJ due to the ability to hold direct pressure. However, IJ access in pts with coagulopathy places the pt at risk for neck hematoma, which can be life-threatening due to airway compromise if inadvertent carotid artery puncture occurs. Here are some ideas to keep in mind:

    1. The safety of large bore tunneled cath (we use non-tunneled, see below) placement has been documented in pts with mild-to-moderate coagulation abnormalities. We use the smaller non-tunneled catheters.

    2. Thrombocytopenia poses a greater risk compared with a prolonged INR!

    3. A subclavian approach should be avoided in coagulopathy due to an inability to effectively monitor or compress the venipuncture site.

With that being said: If the operator is inexperienced, the pt is uncooperative and wont lay still, or if the US is not available, and there is an underlying coagulopathy, femoral access should be attempted for emergent access. The femoral line should be replaced as soon as the coagulopathy is corrected. FFP or platelets can be given prior to the procedure in patients with severe coagulation abnormalities to reduce the risk of bleeding complications, but there is little evidence to support this practice. If this is the case, guidelines should be reviewed for correcting coagulation abnormalities.


Central Catheters

This is a description of non-tunneled catheters and their specifics. There are other types including tunneled catheters, PICCs and ports. These should be read about and understood but are not pertinent in this paper. Non-tunneled catheters are placed percutaneously with the catheter exiting the skin in the vicinity of the venous cannulation site. These catheters are much longer than the catheters used to cannulate peripheral veins and are typically 15-25cm (6-10in) in length. They are also available with 2 or 3 separate infusion channels. The multilumen catheters are the most popular b/c they allow multiple infusions through a single venipuncture site. See the table below for the different types of vascular catheters.




Central Venous Catheter

Sizes (Gauge or French)

Lengths

Single lumen

16 ga, 18 ga, or 20 ga

15cm, 12 cm, 8 cm

Double lumen (18 ga, 18 ga)

7.5 Fr

15cm, 20cm, 25cm

Triple lumen (18, 18, 16 ga)

7 Fr

15cm, 20cm, 25cm

We use triple-lumen catheters. This catheter has an outside diameter of 2.3mm (7 French) and houses one 16-gauge channel and two smaller 18 gauge channels. The distal opening of each channel is separated by 1 cm to prevent mixing of infusated solutions. I will break this down more: There are 3 lines in the one line (1 16 ga and 2 18 ga), the end coming out of the patient will have three ports. These three ports are termed the distal, medial, and proximal ports. These three lines combine into one larger 7 Fr catheter. On the distal end (the end in the patients jugular vein) there are three openings: the proximal opening, the medial opening, and the distal opening. These correspond to the same ports on the proximal end of the catheter. The end hole (distal) or the distal port (has brown cap on it) is best for drawing blood as its not likely to lay in close proximity to the side wall of the vein. There is a higher risk of thrombosis and lower infusion rates with multi-lumen catheters. Infection rates are the same for single, double and triple lumen catheters. See the diagram on the following page.





Figure 1: the middle (242), or distal, port is brown and corresponds to the distal hole (210). The distal port (242) is the 16-ga channel; the left port (241,medial) and right port (243, proximal) are 18 ga channels
Preparation



  1. Internal Jugular Vein Anatomy:

    1. The IJ is a continuation of the sigmoid sinus as it exits the jugular foramen at the skull base. The IJ exits the skull posterior to the internal carotid artery, but assumes a position anterolateral to the common carotid artery as it courses beneath the SCM muscle. At the level of the cricoid cartilage, the IJ is beneath the SCM muscle and more caudally it is located between the 2 heads of the SCM muscle at the base of the neck. Its in this region the IJ is 1-1.5cm from the skin surface. The IJ then joins the brachiocephalic vein posterior to the medial clavicle. The vein is contained within the carotid sheath traveling with the carotid artery and vagus nerve throughout its length. The IJ vein on the right is larger than the left in the majority of patients. The primary landmarks are the SCM muscle, which consists of 2 heads: a sternal head and a clavicular head. Flexing the neck or turning the neck away from the procedure side can accentuate the SCM muscle. The 2 heads of the SCM should be palpated. The sternal head is easier to palpate. The IJ vein emerges just medial to the clavicular head. If the pt’s head is turned contralaterally to the side of the procedure, this directly places the carotid artery posterior to the IJ, making carotid puncture much more likely

  2. Informed Consent:

    1. Informed consent should be given to each patient. Consent for vascular access is implied in emergent situations. The indications, complications, and benefits of the procedure should be explained. The need for a second procedure (i.e. chest tube) if a complication should arise should also be conveyed. Also, an explanation of the procedure being done is courteous.

  3. Analgesia and Sedation: This is really dependant on several things:

    1. Is the patient intubated? If the patient is already intubated, a form of sedation will be given already thru an IV (i.e. Propofol, Ativan, Dexmed.). If this is the case, just be sure the pt is comfortable under the IV sedative being used. Also, lidocaine to the area should still be used as the patient still has the ability to interpret pain.

    2. Are they awake? If the pt is awake, a short acting benzodiazepine (Ativan) can be used to relieve anxiety. If the patient is uncooperative, an opioid (fentanyl) should be used to obtain conscious sedation. This requires vital sign monitoring so should only be done if the patient is in the ER or the ICU.

    3. Topical injection: all patients need lidocaine to the area, regardless if sedated.

  4. Positioning: correct patient positioning maximizes the diameter of the IJ and is associated with increased cannulation success:

    1. Trendelenburg Position: The Trendelenburg position (head down) of 10-15 degrees significantly increases IJ diameter compared with flat positioning. Trendelenburg positioning also decreases the potential for venous air embolism.

    2. Valsalva: The diameter of the compliant vein varies with respiratory cycle. To increase the diameter of the IJ, just ask the pt to perform a valsalva. If the pt is not awake, slight abdominal compression can increase venous distension.

    3. Head Position: The position of the pt’s head does 2 things: influences vein diameter and its relationship to the carotid. Vein diameter is increased with slight head elevation, while the use of a shoulder bolster or head rotation past 45 degrees both decrease vein diameter. The position of the head also influences the location of the vein relative to the artery. The overlap progressively increases with rotation of the head contralaterally from a neutral position. Limiting head rotation minimizes superimposition of the vessels and decreases the risk of arterial puncture. Some head rotation will be needed though to adequately expose the anterior neck.

  5. Sterile Technique:

    1. Each participant in the room should at least be wearing a hair net and mask. The proceduralist and their assistant should follow full sterile technique in gown, glove, mask, and hair. Also, the ultrasound probe should be placed in a sterile cover and sterile jelly used.

  6. Site Preparation:

    1. Wide skin preparation should be used. The prep of choice is chlorhexidine, which comes standard in all kits. This is the preferred agent as it has been shown (compared to alcohol and betadine) to be superior in preventing infections. A wide prep includes the neck and chest above the nipple line. This allows the operator to attempt cannulation at an alternative ipsilateral target (e.g., supraclavicular or infraclavicular subclavian) if the initial plan fails. If difficult access is anticipated, it is prudent to prepare both sides. Remember that the sterile covering in the kit has a small hole in it that will be placed over the sterile site.

  7. Equipment: This is a summary of what all will be used and is included in the kit. Jugular venous catheters are placed using a modified Seldinger (see below for explanation) technique in a series of defined steps. Prior to placement, assemble the following equipment:

    1. Ultrasound machine

    2. Sterile ultrasound transducer gel

    3. Sterile ultrasound sheath

    4. Sterile gloves, gown, surgical mask, and cap

    5. Central line kit

      1. Topical anti-septic

      2. Local anesthetic

      3. Sterile cover for the patient which has a hole for the sterile area on the neck and chest

      4. Finder needle/Local needle

      5. Introducer needle

      6. Introducer syringe

      7. Guidewire

      8. #11 blade scalpel

      9. Tract Dilator

      10. 7 French, triple lumen, 15cm-25cm (length) intravenous catheter




    1. 3 needleless Luer locks: nurse must get these and open them in a sterile fashion and place on the tray

    2. Sterile isotonic saline for flushing: once again, the nurse will place this into your kit

    3. Anti-bacterial covering

    4. Transparent dressing


Internal Jugular Vein Cannulation


  1. Ultrasound Guidance: the US is literally your best friend. There have been numerous studies showing there is a decrease in complications, reduces time to venous cannulation, and increase in successful cannulation rates when the ultrasound machine is used. Basically, the ultrasound will be used to center the IJ on the screen and a wheel will be raised in the area using 1% lidocaine OR the cover on the needle can be used. This is where the needle will be placed. The IJ (like all veins) is compressible with the ultrasound. This is the easiest way to differentiate the IJ from the carotid artery. The probe of the U/S has a small dot on the side, this dot corresponds to the dot on the screen and this is how we differentiate left and right on the ultrasound screen. You can tell which side you are at by gently tapping the lateral aspect of the transducer, which ever side has a shadow on the screen corresponds to the side you’ve just tapped on the transducer. The transducer is placed in transverse orientation over the triangle formed by the two heads of the SCM.  Slowly slide the probe distally, until you find the area of interest, two dark and oval or round appearing vessels.  Use the transducer to compress the vein to confirm that it is indeed the vein and not the artery. Position the vein in the center of your image and place the needle to the midline of the transducer. Estimate or measure the depth of the IJ vein from the skin surface.  You can use the same distance when determining how far from the transducer the needle should enter the skin when the angle of insertion is close to 45 degrees. Align the needle with the longitudinal axis of the vein while advancing it. The needle should be visualized entering the vein. Ultrasound anatomy of the IJ and it surrounding structures is straightforward to comprehend. This can be reviewed on the Sono-Site website (www.sonoguide.com/line_placement.html). This should be viewed prior to all procedures. Also, you will be required to pass a skills lab showing competence on ultrasound. See below for an US image.

  2. Approach to the IJ: There are 3 standard approaches to the IJ and these include central, anterior and posterior. We were thought the central approach and therefore this is what will be described.

    1. Central: Initially, the landmarks of the lateral and medial head of the SCM should be identified and if needed traced onto the skin. The apex of the triangle formed by the heads of the SCM is ~5 cm superior to the clavicle and this should be the general area where the wheel will be raised once the ultrasound is used. This also approximately marks the needle insertion site for the central approach: the apex of the triangle. Once the US is used, introduce the needle lateral to the carotid pulsation felt or seen on the screen @ an angle of 45 degrees to the skin. Direct the needle toward the ipsilateral nipple. This path typically travels alongside or beneath the lateral head of the SCM. If blood is not aspirated after 2.5 cm, withdraw the needle slowly while maintaining constant negative pressure and watching for blood return. If the first needle pass fails, reassess ultrasound anatomy and make a second pass, this time redirecting the needle in the direction indicated by the US. The needle should be visualized entering the vein.




  1. Needle Access:

    1. General Techniques: The IJ should be cannulated using an introducer needle with or without the aid of a seeker needle. We do not generally use the seeker (smaller) needle, instead go straight to the introducer needle. Once again, recall that isolated arterial needle puncture is one of the most common complications of venous access, but is typically uneventful if recognized. Confirmation that the tip of the needle is within the vein is essential prior to dilating the subcutaneous tissue and vein. There is an established learning curve for central venous access procedures. Experienced operators enjoy greater success rates with fewer complications, among both experienced an inexperienced operators, an increased number of introducer needle passes correlates with increased complication rates, which are significantly higher after 2-3 unsuccessful passes. If 2 attempts have been made, the needle should be completely removed and the landmarks reassessed and a new access site



chosen and the assistance from an upper level resident should be sought.

    1. Access with the Introducer Needle

      1. Insert the introducer needle into the skin and apply continuous negative pressure by pulling back on the plunger of the syringe. Penetration into the vein will go unrecognized unless negative pressure is applied, but only a small amount of continuous negative pressure is needed (about 1cc of a 10cc syringe) during forward advancement of the needle.

      2. Always advance and withdraw the needle in the same vector. Lateral movement of an inserted needle can lacerate vessels and should not be done. Prior to any redirection of the needle, it should be withdrawn to the skin surface.

      3. Anticipate that venous backflow into the introducer needle will be quick so steady the needle with your other hand to avoid loosing access when it occurs.

      4. The introducer needle may compress the anterior wall, puncturing both walls simultaneously without entering the lumen. Failure to aspirate blood during needle advancement is common. In this circumstance, withdraw the needle slowly while maintaining continuous negative pressure. Up to ½ of jugular punctures are recognized during needle withdrawal.

      5. Once access is achieved, stabilize the hub of the needle and carefully remove the syringe to avoid dislodging the introducer needle from the vessel.

      6. Cover the hub of the needle after the syringe is removed to avoid air entry during jugular access.




    1. Venous Confirmation: An intraluminal position of the needle can be confirmed by observation of the needle entering the vein with US guided access coupled with a steady flow of dark blood into the syringe. Bright red blood and high pressure pulsatile bleeding are important but imperfect clues to arterial puncture, which can occur, although less frequently, with US access. Moreover, the absence of these signs is not perfectly reliable for excluding inadvertent arterial puncture. Dark, nonpulsatile backflow of blood may be seen with arterial puncture in the face of oxygen desaturation, hypotension, or needle malposition. If there is any doubt, the needles location can be confirmed by pressure transduction (rarely used, but ICU nurse can do for you). If the carotid artery has inadvertently been punctured, withdraw the needle and apply pressure over the site for 5-10 minutes. Jugular venous access can be re-attempted provided anatomic landmarks have not become distorted from hematoma. Inadvertent dilation and cannulation of the carotid artery with a standard catheter does not usually pose a significant problem. However, large bore catheters (like dialysis caths) cause problems and should be left in place and vascular consultation obtained.




  1. Catheter Placement: We place all of our central venous catheters using the Seldinger technique, which refers to the use of a guidewire placed into a vessel to provide a conduit for intravascular device placement.

  1. Guidewire: Once the jugular vein has been successfully accessed, a guidewire should be advanced through the needle. We use a flexible J-tip guidewire, favored b/c it negotiates curvatures and minimizes vessel trauma during passage. The guidewire should always pass smoothly and easily through the needle without resistance. Methods to address resistance to guidewire advancement or withdrawal are discussed below. To place the guidewire:

      1. Position the tapered plastic introducer to straighten the distal J-tip. The orientation of the bevel tip of the introducer needle and the J-tip of the wire medially can help facilitate wire placement.

      2. Maintain the length of guidewire under constant manual control to maintain sterility and avoid its loss off the operating field.

      3. Advance the guidewire about 15cm on the right IJ and 18cm on the left IJ. Advancing the guidewire deeper risks intracardiac or IVC wire placement with the potential for cardiac arrythmia, perforation, and snaring of other IV devices.

      4. Never forcefully advance the guidewire, as this can kink and permanently deform the wire and risk vessel injury. The guidewire should always pass smoothly and easily through the needle without resistance. Resistance to guidewire passage can be due to needle dislodgement, compression of the guidewire against the vessel wall, or anatomic obstruction. Rotating the needle and/or guidewire to reorient the bevel or J-tip may relieve impingement of the guidewire on the posterior vessel wall.

      5. If resistance persists, remove the guidwire and aspirate blood to confirm intraluminal needle position. Reducing the angle of the needle against the skin (from 45 to 30 degrees) may facilitate guidewire passage. Once the guidewire is positioned, hold it firmly in place and remove the needle.

      6. Resistance during guidewire withdrawal can be managed by simultaneous removal of the needle and indwelling wire. Continued resistance may indicate entrapment and warrants diagnostic radiography to evaluate the wire appearance and position. Withdrawing a kinked guidewire through the needle can shear off the wire, allowing it to embolize.

  2. Tract Dilation: Central venous catheters are substantially larger caliber than the needle and guidewire used for venous access. Dilation of the subcutaneous tissue tract is required for catheter insertion and is accomplished by threading a single stiff tapered dilator over the wire to expand the subcutaneous tissue and vein. The skin and fascia catheter tract should be dilated carefully with gentle pressure. Only the soft tissue and vein wall need to be dilated. Overzealous efforts and guidewire kinking risk traumatic vein injury. To place the dilator:

      1. Once the guidewire is in place, make a controlled 3 mm stab incision made in the skin at the entry site with a #11 blade to prevent dilator from catching.

      2. Thread the stiff tapered dilator over the wire, making certain the guidewire does not advance and is not pulled out oat the skin exit site. The guidewire and dilator should never be advanced as a single unit, to avoid venous injury. The wire should serve as an immobile object over which the dilator is passed. Cephalad retraction of the skin may be needed to smooth out redundant neck skin to avoid kinking the wire.

      3. Hold the wire just above the dilator hub, grasp the dilator just above its tip and push it over the guidewire with a firm corkscrew motion. Mild resistance is normal. Excessive resistance may represent an inadequate skin incision, a malpositioned guidwire, or guidewire or dilator deformation. Kinking of the guidewire against the dilator is associated with vessel trauma and puncture.

      4. As described above, cover the dilator opening to prevent air entry

      5. Advance the dilator only to the anticipated depth of the IJ, NOT the entire length of the dilator. For the jugular, the dilator need only be advanced 3-5 cm into the vein depending upon the thickness of the pts neck.

      6. Withdrawal the dilator while maintaining the guidewire position within he vessel. Apply direct pressure to the exit site to maintain hemostasis prior to catheter insertion.

      7. Steady traction of the wire during soft tissue dilation helps prevent wire kinking. Rotating the dilator during advancement often facilitates tract dilation. If resistance is met, it may be related to a kink in the wire, which can be remedied by advancing the wire deeper or withdrawing the kink into the dilator. But, overzealous efforts risks traumatic vein injury.




  1. Positioning the Catheter: After the tissues and vein have been dilated, the catheter is place over the wire and positioned. Thread the guidewire back through the end hold of the catheter until it emerges form the distal (brown=middle) port and advance the catheter over the wire into the vessel. The guidewire is now removed completely from the vein and the patient. If any resistance is met with forward advancement, withdraw the catheter and re-dilate the tract. Insert the catheter to 16-18cm on the right IJ and 20cm for the left IJ. Placing the catheter too deeply is associated with serious sequlae including cardiac tamponade, arrythmias, and central vein perforation.




  1. Catheter Flushing and Fixation: aspirating blood and subsequently flushing each port with sterile saline should confirm proper function of the catheter. The nurse will place 3 Luer locks into the sterile tray, these should be placed initially. Then saline should be aspirated from the tray. This syringe with saline should be attached to each individual Luer lock and aspiration of blood should occur from each port. Once blood is aspirated, the saline and blood are flushed back into the patient.

The catheter can be sutured using 2-0 or 3-0 nylon or silk sutures. There is a catheter anchor attached to the catheter, there is a medial and lateral hole on this anchor. This is where the suture needle should pass and subsequently be secured to the skin.
Confirmation of Jugular Catheter Position

This is accomplished via chest radiography. Following placement, a post procedure CXR is performed to confirm catheter position and exclude peumothorax. The distal tip of the catheter should lie in the lower SVC. The carina and right tracheo-bronchial angle represent reliable landmarks for the pericardial reflection, which represents the lower SVC. Therefore, catheters should be positioned at or above the carina. If a jugular catheter tip is positioned too deeply it can be repositioned at the bedside using sterile technique. Remove the sutures, withdraw the catheter, and re-suture the catheter into place. If a catheter is not in far enough or in the contralateral IJ or subclavian, it will need to be replaced over a guidewire under sterile conditions. The portion of a catheter left out of the body is unsterile and should never be advanced into the patient, not even if it is under a sterile dressing.


Complications and Management
There are a few complications associated with central venous catheter (CVC) placement. They are reviewed here and how to prevent/mange them.
1. Infection and thrombosis. These are the late complications of central venous access. There are numerous literature references to this if this occurs. The point I want to emphasize here is to very frequently monitor the site of insertion for these complications and correlate that to the clinical picture you are seeing in the patient. For example, lets say you have a 37 y.o. male who aspirated and went into ARDS requiring intubation and central line placement. On day 7 of hospital admission he starts spiking fevers, the insertion site of the central line is erythematous with slight purulence, this is likely your source. This can be prevented though by daily inspection of the area.

-Prevention: In a large, prospective cohort study, the following five steps reduced CVC-related bloodstream infections when instituted together. They are termed the Pronovost Checklist:

  • Hand hygiene – An alcohol sanitizer or antimicrobial soap should be used immediately prior to donning sterile gloves.

  • Chlorhexidine skin antisepsis – A chlorhexidine solution should be applied by back and forth rubbing for at least 30 seconds. The solution should be allowed to air dry for at least two minutes and should not be wiped or blotted. Chlorhexidine appears preferable to a povidone-iodine solution.

  • Maximal barrier precautions – All operators should wear a mask, cap, sterile gown, and sterile gloves. In addition, a sterile full-body drape should be placed on the patient.

  • Avoid insertion into the femoral vein – Insertion of a CVC into the subclavian vein is associated with the lowest risk of infection, followed by the internal jugular vein. In one trial, 289 patient had lines placed in the subclavian site or the femoral site. There were fewer CVC-related infections among patients who had a CVC inserted in their subclavian vein (5 versus 22 percent).

  • Remove unnecessary CVCs – A daily review of CVC necessity should be performed, with prompt removal of unnecessary CVCs.

There are also a few topics that are being studied but are not Standard of Care (SOC):

  • Antibiotic impregnated CVCs – A meta-analysis of 11 randomized, controlled trials (2603 catheters) found that CVCs impregnated with chlorhexidien-silver sulfadiazine were less likely to cause bloodstream infection (odds ratio 0.56, 95% CI, 0.37-0.84). However, this finding has not been universal.

  • Nursing supervision – In a prospective cohort study, the patient's nurse used a check list defining best-practice to monitor the procedure, and was empowered to stop the procedure if best-practice was violated. Over a six-month period, the CVC-related bloodstream infection rate decreased from 11 to zero infections per 1000 catheter days. We will delegate and individual in the room to do this for us.

  • Vigilant catheter care – A prospective audit of post-insertion catheter care was conducted over a 28-day period (721 catheter-days). There were 323 breaches in catheter care and four catheter-related bloodstream infections (5.5 infections per 1000 catheter-days). The major breaches included dressings that were not intact (158 breaches per 1000 catheter-days) and incorrectly placed caps (156 breaches per 1000 catheter-days). This study suggests that there is substantial opportunity to better standardize and improve the maintenance of CVCs. Such care should also target earlier recognition of potentially infected catheter sites.


2. Arrhythmia: Ventricular dysrhythmias and bundle branch block are well recognized complications during central venous access procedures. Periprocedure arrhythmias are universally the result of guidewire or catheter placement into the right heart. This will be recognized on the monitor as an arrythmia (usually PVC’s).

-Prevention: Limiting the depth of guidewire insertion to less than 16 cm avoids this complication. Catheter migration up to 3 cm is common with patient movement and repositioning may cause delayed symptoms.
3. Vascular injury: Arterial puncture is noted in 3 to 15 percent of central venous access procedures [4]. Immediate recognition and management of arterial puncture usually prevents subsequent complications.

-Treatment: Once an arterial stick is suspected, the needle is immediately withdrawn and direct but nonocclusive pressure applied to the site continuously for 15 minutes to prevent hematoma formation. Unrecognized arterial cannulation with subsequent dilation and catheter placement is associated with life-threatening hemorrhage and neurologic complications. If you dilate and place a catheter into the carotid, do not remove the line. Just call the surgeon of your preference and talk it out. Likely, they will tell you to remove it and hold pressure. Late recognition of arterial cannulation increases the risk of hemorrhagic complications that may require surgical intervention. Measuring intraluminal pressure with a transducer prior to dilation aids in recognizing arterial puncture if location is unclear.

-Prevention: use the ultrasound and do not rotate the neck so much you “stack” the IJ on the carotid.
4. Pneumothorax: Free aspiration of air into the syringe may occur with pleural puncture but is often the result of incomplete seal of the syringe and needle. Suspected pleural puncture should prompt close attention for signs or symptoms of cardiopulmonary distress due to pneumothorax. Pleural puncture can quickly evolve into tension pneumothorax with hemodynamic collapse, especially in patients receiving positive pressure ventilation.

-Treatment: if this occurs and is confirmed on CXR, get the chest tube cart, touch base with the surgeon of your preference, and place a chest tube. The IR team also places chest tubes but the likelihood of there help is slim.

-Prevention: Do not move to inferior when placing your line. Stay at the apex of the SCM triangle and do not advance the needle past your IJ while using the ultrasound. These have never been validated and instead are experience from the placement of these lines. Also, bear in mind that the IJ is shallow so you should not have the needle in to the hub!! Another good practice is to not switch sides in an emergency situation. This is due to the idea that if you cause one pneumo, that’s better than causing 2 pneumos! Therefore, avoid contralateral supradiaphragmatic access attempts in close succession due to the potential for bilateral pneumothoraces.
5. Venous air embolism: Central venous access procedures create a risk for venous air embolism. Venous air embolism is a serious and poorly recognized complication that can occur at the time of CVC insertion, while the catheter is in place, or at the time of catheter removal. Air is easily entrained into the vascular space when a needle or catheter is left open to the atmosphere. Fatal doses of air measuring as little as 20 mL can be aspirated in seconds through a large bore catheter. Upright positioning, hypovolemia, spontaneous inhalation during instrumentation, and inattention to catheter seals increase the risk for entraining air. Affected patients can suffer cardiovascular and pulmonary symptoms including tachyarrhythmias, chest pain, cardiovascular collapse, dyspnea, coughing, hypoxemia, and respiratory distress. Symptoms contemporaneous with central line insertion or manipulation are highly suspicious for venous air embolism.

-Treatment: Left lateral decubitus and Trendelenburg positioning to trap the air in the right ventricular apex is often recommended but has not been rigorously studied. Supportive measures including fluid resuscitation and adrenergic agents should be used as needed. One hundred percent inspired oxygen speeds air resorption.

-Preventing air embolism: Venous air embolism can occur at the time of CVC insertion, while the catheter is in place, or at the time of catheter removal. Trendelenburg positioning, Valsalva maneuver, prompt needle/catheter occlusion, and tight intravenous connections help to avoid this complication during CVC placement. Prior to CVC removal, patients should be placed in the supine position. The CVC should be removed during exhalation, when intrathoracic pressure is greater than atmospheric pressure. Firm pressure should be applied for at least one minute following removal.
Factors Associated with Fewer Mechanical Complications
Mechanical complications are defined as bleeding, blood vessel injury, and pneumothorax. Four factors are associated with fewer complications: increased operator experience, fewer insertion attempts, ultrasound guidance and confirming placement.

Operator experience — It is unknown how many CVCs should be inserted by an operator each year to maintain his or her skills. However, experience is clearly important. In one prospective cohort study, operators who had previously inserted more than 50 CVCs were more likely to be successful at inserting subsequent CVCs, with fewer complications.

Limiting attempts — The number of attempts is also related to the likelihood of a mechanical complication. In a prospective cohort study, the incidence of mechanical complications was sixfold higher when insertion was attempted more than three times, compared with successful insertion on the first attempt. It is, therefore, reasonable for an operator to seek assistance if a CVC cannot be successfully inserted after three attempts.

Ultrasound guidance — Real-time two-dimensional ultrasound guidance is superior to blind, landmark-guided techniques, particularly when used during CVC insertion into the internal jugular vein. This was best demonstrated by a metaanalysis of 18 studies (1646 patients) that compared CVC placement guided by landmarks versus two-dimensional ultrasound. Ultrasound guidance markedly reduced insertion failures in both adults (adjusted relative risk 0.14, 95% CI 0.06-0.33) and infants (adjusted relative risk 0.15, 95% CI 0.03-0.64) when the CVC was inserted in the internal jugular vein. In addition, the risk of complications was reduced approximately twofold. The benefit of ultrasound to guide subclavian and femoral vein placement was uncertain. Despite the apparent benefit of using two-dimensional ultrasound guidance for IJ insertion, routine use of Doppler to identify blood flow does not appear to be beneficial for subclavian line insertion.

Confirm position — A newly placed CVC is frequently used before it has been confirmed by a chest radiograph that it is correctly positioned. This is most common in the operating room and in emergent situations. Failure to confirm the position can be problematic since clinician judgment does not consistently predict catheter malposition or other mechanical complications, especially with less experienced operators. A promising technique has been developed that uses a right atrial electrocardiogram (ECG) to confirm that a CVC has been accurately inserted. A randomized trial that compared CVC insertion using this technique with CVC insertion without it found that use of the technique improved the rate at which CVCs were correctly positioned (96 versus 76 percent).

Complications of central venous catheterization



Immediate

Bleeding

Arterial puncture

Arrhythmia

Air embolism

Thoracic duct injury (with left SC or left IJ approach)

Catheter malposition

Pneumothorax or hemothorax

Delayed

Infection

Venous thrombosis, pulmonary emboli

Catheter migration

Catheter embolization

Myocardial perforation

Nerve injury

References:

The ICU Book. 3rd Edition. Paul L. Marino

Pocket ICU. 1st Edition. Frendl, Gyorgy; Urman, Richard



UpToDate: Overview of Central Venous Access, Placement of Jugular Venous Catheters


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