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 – Quinton (dialysis) – Hickman – Cook – Groshong - Leonard - Corcath • 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 – Enterococcus 25% 10% – Candida* – Staph aureus 9% – * 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 blood Differential 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

Infusion Lipid Basic drug Acidic drug None

Catheter Declotting

Deposit waxy high pH ppt (phenytoin) low pH ppt (Ca, PO4) blood clot Un-occluder 70% ethanol 1 hour, 1x 7.5 % NaBicarb 1 hr, 1-2 x 0.1 N HCl 20 min, 3x/2 hrs fibrinolytic 2 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.