Central Lines:A Primer

• Tamara Simon, M.D.

• July 2004, updated August 2005

Types of Lines• Non-tunneled (jugular, femoral, subclavian)• External Tunneled Catheters

– Broviac - Leonard– Quinton (dialysis) - Corcath– Hickman– Cook– Groshong

• Internal (Totally Implantable) Catheters– Mediport– Infus-a-port– Port-a-cath– Pas-port

• Peripherally Inserted Central Catheters

External Tunneled Catheters• Examples:

– Broviac, Quinton, Hickman, Cook, Groshong– Have a portion exits the skin and a Dacron cuff just inside the

insertion site (fibrosis) with ends in female Luer lock with needleless cap

• Insertion/Removal:– Surgically under sterile procedure– Inserted into external jugular, subclavian, or cephalic vein with tip

on right atrium; other end is tunneled subcutaneously along anterior chest wall

• Home Care– Dressing changes and heparin irrigation 3x/week– No swimming in oceans, lakes, and rivers

External Tunneled Catheters• Uses

– Long term up to several years– Blood draws, medication/TPN/blood administration

• Complications– Infection (site or bacteremia), air embolus, clotted catheter,

damage

• Advantages– Alleviates blood draws, use immediately (after xray confirmation)

• Disadvantages– Requires home care– Ever-present source of infection, ever-present on body

Internal Catheters• Examples:

– Mediport, Infus-a-port, Port-a-cath, Pas-port– Tunneled beneath the skin to a subcutaneous infusion port or reservoir

attached to silastic catheter that enters a central vein- reservoir is self-sealing and accessed with tapered 20-22 gauge Huber needle

• Insertion/Removal:– Surgically under sterile procedure– Catheter inserted into central vein with tip on right atrium; other end

is tunneled subcutaneously and attached to reservoir

• Home Care– None if de-accessed– Occlusive dressing if accessed

Internal Catheters

• Uses– Long term up to several years

– Blood draws, medication/TPN/blood administration

• Complications– Infection (bacteremia), air embolus, clotted catheter

– Lower rates of complications compared to external devices

Internal Catheters

• Advantages– No home care required, except when accessed

– Protective barrier of skin, hardly noticeable

– Use immediately (after xray confirmation)

• Disadvantages– Needle stick to access device

– Needle change every 7 days for infection control if accessed for continual use

PICCs• How to get it done

– Deb King, Vascular Access Coordinator, office phone is 860-4312.   – Interventional radiology- over 5 kg, call IR– Newborn center- under 5 kg, call NBC– Surgery- on weekends, call consult pager

• Insertion/Removal– Under sterile procedure– Small caliber silastic catheter is inserted in antecubital vein and advanced

so that the tip is in the SVC/RA

• Home Care– Dressing changes weekly or if wet or soiled– heparin irrigation after each use or 3x/week– No swimming in oceans, lakes, and rivers

PICCs

• Uses– Short term, up to 6-8 weeks

– Average dwell time 21 days

– Blood drawing if 4 Fr or larger; medication/ nutrition/ blood administration

• Complications– Infection (site or bacteremia- 2.2%), phlebitis, air

embolus, clotted catheter (8%), damage

PICCs

• Advantages– Alleviates blood draws, use immediately (after xray

confirmation)

• Disadvantages– Requires home care

– Ever-present source of infection

– Not tunneled, so dislodgement more likely if precautions are not taken

Complications: Causes of Catheter Loss

• Persistent infection (4-60%)– Pediatric 22%– Adult 27%

• Inability to clear occlusion– Pediatric 8%– Adult 17%

• Mechanical, dislodgement, and damage – Pediatric 15%– Adult 12%

Complications: Infection

• Most common complication of central venous access

• Increased risk with external devices and multiple lumens

• When suspected (fever, redness, swelling, and/or drainage), get CBC, CRP, central blood culture, +/- DIC panel, peripheral blood culture, site drainage Gram stain and culture

Complications: Infection

• Microbiology– Coagulase negative staph* 38%– Gram negative rods 25%– Enterococcus 10%– Candida* 9%– Staph aureus– * lipids increase risk, especially of slime

producers

MMWR 2002, 51:12

Complications: Infection

• Pathogenesis– Migration of skin flora from insertion site to

catheter tip– Contamination of hub leading to intraluminal

infection– Catheter materials differ in bacterial adherence

• Infection Rate– Non-tunneled > Tunneled > Implanted– Central > Peripheral

Complications: Infection

• Types of infection:– Tunnel or pocket infection– Exit site infection– Catheter-related bacteremia– Phlebitis

Tunnel or pocket infection

• Redness, swelling, and purulent drainage from tunnel of pocket around port or external CVC (beyond 2 cm)

• Organisms usually Gram positive (Staph epi, Staph aureus), can be Gram negative (Pseudomonas)

• Treatment consists of removal of CVC, IV antibiotics (vancomycin initially), debridement or drainage of pocket/tunnel

Exit site infection

• Originates at site where CVC exits skin (within 2 cm)

• Pain, redness, or swelling around port or external CVC without systemic signs of infection

• Organisms usually Gram positive (Staph epi, Staph aureus)

• Treatment consists of aggressive site care and oral/IV antibiotics; if Dacron cuff is visible, it is very difficult to clear infection and removal of CVC is usually necessary

Catheter-related Bacteremia/Sepsis

• No other source of infection found, despite extensive search

• Positive blood culture drawn from CVC which shows a 5-10 fold or higher concentration of organisms than in the peripheral blood; usually multiple blood cultures (Todd says two consecutive cultures from central line suffices)

• Temporal relationship between catheter manipulation and development of symptoms

Catheter-related Bacteremia/Sepsis

• Gram positive and Gram negative organisms• Treatment consists of IV antibiotics (vancomycin

plus Gram negative +/- Pseudomonas coverage initially); depending on organisms and duration of persistence, it is very difficult to clear infection and removal of CVC is usually necessary

• Consideration of distant complications such as endocarditis and metastatic abscesses

Phlebitis

• Inflamed, palpable, thromobosed vein

• Often due to physiochemical factors rather than infection

• Increases the risk of infection, observed with insertion-site infections

Accessing CVC’s• Damaging:

– Tincture of Iodine damages Silastic– Clamps and hemostats with teeth damage catheters– Small syringes generate too much pressure so use 5-10

ml catheters (central lines are delicate)• Establish patency before infusing meds/ fluids• Close clamps when circuit is open (air emboli)• Withdraw 3 ml blood from external tunneled CVC

and 5 ml from internal CVC before sampling for lab tests

• Force fluid into catheter against significant resistance

• Use HCl in polyurethane catheters

Complications: Thrombosis

• Complete occlusion: inability to flush or aspirate CVC

Differential diagnosis: • Fibrin sheath formation around tip• Venous thrombosis beyond tip of CVC (more common if tip in

high SVC or above compared to low SVC or RA• Catheter or tip migration (consider CXR)• Intraluminal clot• Intraluminal drug precipitation• Mechanical such as kinking or pinching off between

clavicle/rib (consider CXR)

Complications: Thrombosis

• Partial occlusion: ability to flush but not to aspirate bloodDifferential diagnosis:

• Fibrin sheath at tip of CVC acting as ball-valve• Tip up against vessel wall- positional

– Reposition patient (reverse Trendelenberg), then have them valsalva, cough, take deep breaths, raise arms over head

• Tip migration too low, CVC compressed as AV valve closes

Catheter Declotting

• Assessment: determine if occlusion was caused by blood or drug precipitate

• Blood clot– Treatment of choice is TPA 1 mg/ml (Alteplase) at max

dose 0.4 mg/kg; also can use urokinase 5000 U/ml– Instill per nursing protocol (see website)

• Drug precipitate (completely preventable)– Success of restoring patency is variable– HCl can be used to lower pH and NaBicarb to raise pH– 70% ethanol can treat lipid precipitates

Catheter Declotting

Infusion Deposit Un-occluderLipid waxy 70% ethanol

1 hour, 1xBasic drug high pH ppt 7.5 % NaBicarb

(phenytoin) 1 hr, 1-2 x

Acidic drug low pH ppt 0.1 N HCl(Ca, PO4) 20 min, 3x/2 hrs

None blood clot fibrinolytic2 hrs, 1x/24 hrs

Technique: Lock Technique

• Volume for lock technique equal to priming volume of catheter (3 ml/5 ml, and/or check box of similar device) plus add on devices

• Clamp catheter or T-connector• Disconnect IV tubing• Remove needle-less cap• Remove all add-on devices• Attach 5 ml syringe with un-occluding agent,

unclamp

Technique: Lock Technique

• Infuse proper volume gently with push-pull action• Clamp catheter or T-connector• Wait designated time based on un-occluding agent• Aspirate un-occluding agent and discard• Infuse saline flush to test catheter patency

Technique: Lock Technique

• …but you can’t infuse un-occluder or can’t aspirate it back…

• Clamp catheter• Attach empty 10 ml syringe• Pull plunger back 8-9 ml to create controlled

negative pressure• Re-clamp catheter• Attach 5 ml syringe with un-occluding agent or

saline (if unable to aspirate it back)

Technique: Lock Technique

• Un-clamp catheter and allow fluid to flow into catheter

• Wait appropriate dwell time

• Aspirate un-occluder

• Test for catheter patency

• If it’s TPA, be sure to dilute it with NS

Complications: Mechanical• Dislodgement

– Suspect if:• No blood returns• Dacron cuff outside skin surface- don’t push it in!• Subcutaneous swelling at site of implanted port

– Associated with:• cuff placement 0.5-2 cm from exit site• smaller lumens (6 Fr or less)• young age (<3 years)

– X-ray to locate catheter tip– Dye study

Complications: Mechanical

• Damage to internal/external parts of CVC– More common in external devices– Trauma, detachment needle puncture, wear and tear– Clamp catheter to avoid exsanguination– Associated with young age (<3 years)– Leaks/breaks can occur anywhere on external segment

• repair is possible if there is adequate length of old catheter to splice on the new segment

• each CVC has a permanent repair kit, be sure to get the correct one- external segment, male connector, glue

• Repair is a strict sterile technique by specially trained RN or MD

Complications: Rare

• Air embolism- left Trendelenburg, oxygen, clamp catheter

• Catheter embolism – visible on xray, happens with longer duration and occlusion, invasive retrieval

• Exsanguination• Respiratory decompensation- catheter tip in

pulmonary artery• Cardiac tamponade- erosion of atrial wall

References

• Central Lines Used at UNC Hospitals, September 1999.

• Konsler GK. Management of Central Venous Catheters: Troubleshooting, August 1999.

• Band JD. Central venous catheter-related infections: Types of devices and definitions. Up To Date, January 15, 2002.

• Teoh DL. Tricks of the Trade: Assessment of High-Tech Gear in Special Needs Children. Clinical Pediatric Emergency Medicine. 3(1), March 2002.