Christine Hanley. Jan, 2001. Totally implantable venous access devices [online]. Seacroft University Hospitals, Leeds, UK. Available from http://www.cysticfibrosismedicine.com
Totally implantable venous access devices (T.I.V.A.D) allow the administration of chemotherapy, antibiotic therapy and parenteral nutrition without limiting the concentration of the fluid or the speed of administration. The port is made of titanium, the septum of silicone. It is a closed system that is totally implanted subcutaneously. They can be used long term (up to 2000 punctures over 2yrs or longer) as long as they are cared for correctly.
These devices have proved valuable in overcoming problems of venous access for many patients having regular intravenous antibiotic therapy. It is essential that both family and professionals are familiar with the use of these devices. For older patients, the smaller PAS Port is a preferred alternative to the Port-A-Cath (Burdon et al, 1998).
When it is decided that a child will benefit from the insertion of a Port-A-Cath or PAS Port device, the patient and family are contacted by the Cystic Fibrosis Nurse Specialist in order to discuss the pre- and post-operative care, practicalities of caring for the device and potential complications. This meeting usually takes place at the family’s home and for families who are not usually cared for at the unit a visit to the ward is also offered. The pros and cons of TIVADs are discussed with older patients in out-patients or during admissions. In Leeds the various ports are demonstrated and a patient who has a device fitted is asked to talk of their own experience with it. If a device is to be fitted in a patient who is treated at an outlying hospital it is vital that the hospital is aware of the practicalities of caring for the device and ideally this should be taught before the patient is admitted for insertion of the device. Follow-up teaching and after-care is provided by the Cystic Fibrosis Nurse Specialist. It is essential that all TIVADs are inserted by surgeons or radiolologists with appropriate experience. The TIVAD must be flushed monthly when not in use. It is also vital that the device is cared for by staff or parents who are fully trained and have expertise in the everyday care of such devices. When cared for properly complications are rare, although patients with diabetes mellitus need to pay particular attention to aseptic technique and blood sugar control (Horn & Conway, 1993). If parenteral nutrition is to be given via the TIVAD, advice should be sought from the local CF centre for regimens to minimise the risks of catheter blockage. In case of blockages advice should also be sought from the local CF centre.
Always use aseptic technique when handling the port, giving medication or taking blood samples.
Only access the port when strictly necessary for the patient's treatment - the less the intravenous line is handled, the less there is an infection risk.
Only use the correct access needles (huber point).
Always maintain a closed system to prevent infection or an air embolism.
Never access the port unless you have been shown how.
Never mix bolus drugs or infusions in the line, always flush with saline in between (SASH: saline, administer medication, saline, heparin).
Always use a 10ml or larger syringe - smaller syringes exert high pressures and risk damaging the line. Do not exceed a pressure of 40 psi.
Always access the port at an angle of 90 degrees to the septum.
Insert the needle steadily until you feel the bottom of the port.
Avoid excessive pressure on the needle once it has reached the bottom of the port.
Needle length - should be long enough to reach the bottom of the port when inserted. When using the GRIPPER needle or the winged infusion set, the needle hub should be flush against the skin surface.
To avoid injection into the sub-cutaneous tissue, once the septum is punctured, do not tilt or rock the needle as this may cause fluid leakage or damage to the septum.
Withdraw at least 5mls of blood and discard.
Withdraw the desired amount of blood.
Immediately flush the system with 20mls of 0.9% saline.
Instill 5mls of heparin (100iu/ml) establishing a heparin lock. Maintain positive pressure by clamping the extension set whilst injecting the last 0.5mls.
5. Precautions and complications
Sports: If the patient is involved with activities or occupations which involve excessive or repetitive upper extremity and/ or shoulder or pectoral girdle motion they should be informed that they may increase the possibility of catheter fragmentation due to compression of the catheter between the clavicle and the first rib (The pinch-off syndrome).
Medical procedures: These should be restricted on the patient's arm in which the system is implanted. Don't withdraw blood from/ or infuse medication into the arm in which the implanted system is located in unless you are using the port. Inadvertent puncture of the catheter will result in catheter damage. Do not measure the patient's blood pressure on this arm, since catheter occlusion or damage to the catheter could occur (Simms Deltec).
Potential Complications: Air embolism Artery or vein puncture, Arteriovenous fistula Brachial plexus injury, Cardiac arrhythmia, Cardiac puncture, Cardiac tamponade, Catheter disconnection or fragmentation with possible embolism of catheter, Catheter occlusion, Catheter rupture, Drug extravasion, Erosion of portal / catheter through the skin and / or a blood vessel, Fibrin sheath formation at the catheter tip, Haematoma, Haemathorax, Implant rejection Infection / bacteremia / sepsis, Migration of port / catheter, Pneumothorax, Thoracic duct injury, Thromboembolism, Thrombosis, Thrombophebitis. These complications also apply to the port-a-cath system.
Centres for disease control and prevention guidelines recommend changing the dressing whenever it is soiled, damp or loose
Needles should be changed every 7 days. However, there is some evidence that it is safe to leave needles in for 2 weeks without changing although In the Leeds units this resulted in a significantly higher incidence of port infections (unpublished data).
Difficulty in flushing / infusing: Possible causes and possible solutions.
Clamps may be closed. Open clamp.
Catheter may be wedged in a smaller vessel or tip may be pressed against the vessel wall. Have the patient lie flat and get them to move their shoulders and rotate their head. Check flow. If resistance is still detected, blockage may be caused by drug precipitation fibrin at the catheter tip, intraluminal clot or a pinched catheter. If it is a chest placed system, the catheter may be kinked or 'pinch- off' syndrome may be occurring. Sign of this - unable to flush or aspirate fluid when the patient is sitting, but aspirates and flushes easily when lying down.
Needle may not be inserted completely or may be too short to pass through the septum to the bottom of the port. Insert the needle steadily through the septum or re-access the of the port chamber. port with a longer needle. Insert the needle completely through the portal septum at a 90 angle to the port.
Catheter may be occluded because of drug precipitate, fibrin deposition at the catheter tip or an intraluminal clot. Using a 10ml syringe, flush with 0.9% saline alternating between irrigation and aspiration. If resistance is still felt and thrombosis is suspected consider Urokinase. See Urokinase in drug database.
Difficulty aspirating blood: as above
Pain
Portal pocket or catheter insertion site. Check for drainage. Discharge at the insertion site. Port may be infected. Assess the patient for other signs or symptoms of infection.
Vein may be irritated because of implantation technique, infusion of acidic or alkaline solutions, or infected vein related to contaminated catheters.
Needle may have been accidentally pulled. Re-evaluate the site. Fluid may be infusing into the tissue.
Catheter may have ruptured. Diagnosed by contrast fluid into the tissues. Undertake a pasportagram.
Moisture at or around the insertion site
Dressing may have been exposed to water or excessive perspiration. Inquire about recent activity which may explain dampness of the dressing.
Connection between the needle extensions and tighten connectors. Extension set may be loose.
Needle may be displaced. Check position of the needle ensure correct needle length. Check that dressing adequate to secure the needle.
Needle may have been accidentally inserted into the surrounding tissue.
Septum integrity may have been compromised. Notify physician of leaking from the port. May need contrast study to confirm this.
In the Leeds Unit, all patients who undergo a course of home intravenous antibiotic therapy are given written and verbal information on the nature and signs of anaphylaxis and what course of action to take in the event of them suffering an anaphylactic reaction. They are discharged with an anaphylactic kit. This comprises of
One epipen®, auto injector 0.3mg (Adrenaline BP 1 in 1000); delivering one single dose (0.3mls) of 0.3mg of adrenaline. (Manufactured by Meridan Medical Tech. Inc.; St. Louis. USA.
6 tablets - chlorpheniramine - 1 to be taken.
12 tablets - prednisolone - 12 to be taken.
Patients are advised to use the kit in the case of anaphylaxis, to phone for an ambulance stating that they are experiencing an anaphylactic reaction.
Burdon J, Conway SP, Murchon P, Lansdown M, Kester RC. 5 years experience of the PAS Port intravenous access system in an adult unit for cystic fibrosis. Eur Resp J 1998; 12: 212-216
Horn CK, Conway SP. Candidaemia: risk factors in patients with cystic fibrosis who have totally implantable venous access systems. J Infect 1993; 26: 127-132
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