Indwelling Venous Catheters

Synonyms: Hickman® catheter, skin-tunnelled central venous catheter, Groshong® catheter, implantable port, totally implantable venous access system (TIVAS, Portacath®, subcutaneous port), peripherally inserted central catheter.

These devices allow venous access for a period of months or even years, allowing infusions and withdrawal of venous samples.¹ They are usually inserted into major veins with a section tunnelled under the skin. Such devices are often inserted with the aid of radiological guidance. Peripheral devices are also used which gain access to the major veins from a distal insertion point, usually in the antecubital fossa. Catheters may be made of polyurethane or silicone and can have 1, 2 or 3 lumens.

• Hickman® catheter:
  • The catheter is placed such that its tip lies within the right atrium, the superior vena cava (SVC) or at the junction between them.
  • It is most often placed via the subclavian vein as it is nearest to the SVC, but the right internal jugular vein is a straighter route with less risk of damage to the carotid artery and vagus nerve.
  • May also use cephalic or external jugular veins.²
  • The line has a section tunnelled subcutaneously to separate the venous entry site from the external environment and potential infecting microorganisms.
  • A cuff helps to anchor the line in-situ and subcutaneous tissue grows around it to help make the line less prone to displacement.
  • A Hickman® catheter cuff should be placed not less than 5cm from point of entry on the skin but other types of catheter are widely used, some with cuffs much further from the exit.
  • Such lines usually need a cut-down procedure to remove them, usually under general anaesthesia, because of the need to use traction/surgical techniques to dissect out the embedded cuff.³
• Groshong® catheter:
  • These lines may be used centrally as for a Hickman® catheter, but can be inserted peripherally.
  • They have a valve which closes off the lumen of the line from the blood.
  • Infusion or aspiration of the line will open the pressure-sensitive valve.
• Implantable venous access port (Portacath®, totally implantable venous access system – TIVAS – subcutaneous port):
  • This device is usually attached to a tunnelled central line and completely hidden under the skin.
  • A thin rubber self-sealing disc with an underlying cavity allows a needle to be inserted through the skin and infusions to be given/blood samples to be withdrawn.
• Peripherally inserted central catheter (PICC):
  • These lines are inserted into a peripheral vein, usually the cephalic vein in the antecubital fossa and 'unwound' upwards into the subclavian vein/superior vena cava.
  • They are firmly secured with tape or sutures.
  • They tend to be used for relatively short-term venous access, e.g. prolonged course of antibiotics, but can be used for periods of up to several months.

• Adminstration of a course of chemotherapy
• Administration of long-term intravenous medications, e.g. antibiotics
• Administration of parenteral nutrition
• Recurrent transfusion of blood products
• Temporary venous access for haemodialysis before construction of surgical anatomical access
• Drawing of multiple blood samples for disease/treatment monitoring

• Patients may manage their lines themselves or with the help of carers/nursing staff.
• Patients with lines in-situ should receive instructions on how to care for their lines, advice on complications, and what to do if they experience problems.
• When assessing a patient with a line in-situ, it's a good idea to ask to see any literature they have regarding it, to confirm initial indication and see if any support is available to manage complications, or appropriate place of referral to deal with problems.

Flushing

• To prevent occlusion and thrombosis such devices require regular flushing, usually with a heparinised saline solution.
• This is usually done on a daily to alternate day/twice weekly basis.
• Patients (and healthcare professionals) should be aware that they shouldn't use force to flush an occluded catheter.
• Groshong® catheters require less frequent flushing (approx. weekly) and are purported to be cheaper to maintain and to occlude less frequently.
• However, comparative studies of use of Hickman® and Groshong® catheters in real-life clinical scenarios have shown little difference in occlusion or thrombosis rates or cost of maintenance.^4,5

Hygiene

• The venous access port and entry site should be kept scrupulously clean and the latter regularly checked for any signs of infection.
• Alcohol-impregnated wipes may be used to clean the exterior surfaces of the devices.
• When bathing and showering the access ports are usually kept dry in plastic coverings.

Prevention of air entry into line

Non-valved lines must be kept clamped closed when not in use, and care taken not to unclamp them until the port entry is sealed.

Avoidance of damage

Care must be taken not to cut lines with scissors etc. whilst adjusting dressings, or to allow chemicals that may damage the line to come into contact with it.

Early complications (associated with insertion or immediate aftermath)

• Complication rate around 4% of all procedures, with bruising and pain affecting about 8%.⁶
• The rate of complications of insertion is significantly decreased by the use of radiological guidance.⁶
• Potential early complications include:
  • Haemorrhage
  • Arterial puncture
  • Pneumothorax
  • Venous thrombosis
  • Air embolism
  • Malpositioning
  • Catheter transection
  • Catheter migration
  • Guidewire entrapment

Late complications

• Catheter occlusion may occur due to:
  • Intra-luminal thrombus
  • Fibrin sheath formation at catheter tip
  • Malpositioning of tip against vessel wall
  • 'Pinch-off' of catheter between clavicle and first rib
  • Thrombosis within the vessel in which the line is located
• Thrombosis rate is approximately 3%,⁶ but asymptomatic thrombosis rate is probably significantly higher. Thrombolytic agents may be used to remove clots.⁵
• Infection occurs in about 4 %,⁶ and should be treated with systemic antibiotics and/or removal of the device according to clinical condition and local procedures/guidelines.
• Intra-luminal antibiotic solutions,^7,8 antifungal agents⁹ and ethanol/water mixtures (currently an experimental treatment)¹⁰ may be used to treat colonisation/infection of long-term indwelling central venous catheters.
• Chemotherapy patients are obviously at increased risk of infection and any suspicion of sepsis should prompt referral to secondary care for assessment.
• The device may fail in about 1% of cases.⁶
• Air embolus appears to be rare if lines are correctly cared for.
• Catheters may break and be dislodged, especially if 'pinch-off' occurs repeatedly.

• Hickman® is a registered trademark of C.R. Bard Inc., as applied to a central venous catheter.
• Groshong® is a registered trademark of C.R. Bard Inc., as applied to a central venous catheter.