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When Good Lines Go Bad

Donna Magid, M.D., M.Ed.

VENOUS CATHETERS

Central venous placement: the longer the line will be in the patient, the more important meticulous placement becomes. Interventional radiology is assuming a larger role as the need for long-term catheters grows.

Indications for long-term placement:

  • Infusion of fluids: antibiotics, chemotherapy, parenteral nutrition
  • Hemodialysis: requires high volume, simultaneous inflow and outflow (400-450 cc/min in and out compared to 0.4 - 0.7mL/sec for an IV)
  • Pheresis: also two way, but slightly slower rate requirement than hemodialysis

Anatomic variants result from failures of formation and or regression during embryonic development. Prior catheterization also modifies anatomy and ease of access.


Access sites for central venous placement:

PICC: peripherally inserted central catheter (deep venous system, upper extremity)

  • Long term use, but smaller caliber limits
  • Basilic vein if possible: it is larger and there are fewer angles to the axillary vein
  • Cephalic vein if necessary: it is smaller and there are angles near the axillary vein junction

Internal jugular (IJ): the classic central line

  • The IJ is the continuation of the sigmoid sinus
  • Right is usually greater than left
  • Ultrasound is preferred to “blind” insertion

External jugular (EJ): a favorite for quick access on the Osler Medical Service

  • The EJ drains the face
  • Better for short term access
  • Not for tunneled lines, because it is smaller diameter and tortuous

Femoral vein: a site of last resort

  • Probable increased risk of thrombosis and infection
  • Patient objections/discomfort; site cleanliness issues

 

Catheter material

Silicone: soft, biocompatible, usually long term use

  • High coefficient of friction makes wires difficult
  • Newer hydrophobic wires help placement

Polyurethane: stronger, stiffer, allowing greater lumen per caliber. Bedside use

  • Lower coefficient of friction, steel wires OK
  • Stiff, but softens in body


Tips:

  • End-hole is standard
  • Valve tip for blood withdrawal, no retrograde flow at rest
  • Staggered-tip dual lumen, for simultaneous aspiration/infusion


Subcutaneous ports: Sub-q ports are good for long term use in outpatients. There is a certain geneticist at JHU who once lamented “every one of my patients has a peg and a port.”

  • Titanium or plastic ring prevents CT/MRI interference
  • Silicon septum – provides up to 4000 uses with special needles

 

Pre-procedure imaging:

  • CXR: indicated when there is chest wall disease, chest wall deformity, or mediastinal disease or deformity
  • Ultrasound: decreases the risk of pneumothorax… the “sight rite”


Line Complications:

  • Malpositioning: line misplaced originally, or migrated. Risks: thrombosis, ensheathment, turbulence, pressure. An ensheathed tip may tear vessel wall at removal
  • Repositioning: an originally acceptably placed line may change position spontaneously. Most common in bedside lines place without US, subclavian lines, obese patients, female patients, a move to the upright position. There is also spontaneous migration to azygos and jugular veins. Patients with developmental or acquired distortions of anatomy experience greater rates of repositioning
  • Hematoma
  • Pneumothorax: decreased significantly with ultrasound guidance
  • Air embolism: occurs when the patient inspires during insertion or removal. If suspected, patient should be put in the left lateral decubitus position to hold the air in the right atrium
  • Extravasation
  • Catheter fracture: especially if pinched, subclavian
  • Flushes / can’t aspirate: clot, positional, fibrin sheath
  • Thrombosis: especially in the brachial vein or upper SVC
  • Catheter associated bacteremia: 10% at 30 days, 35% if > 30 days, but patients with long term catheterizations also tend to be immunocompromised at baseline.
  • Local infection (entrance site)

 

July 2017 - Donna Magid M.D., M.Ed.