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A cannula is a small plastic tube that is placed into your vein. It is used to give medicine intravenously (into your bloodstream). Going home with a cannula in place avoids the need to use a needle to insert a new cannula each time intravenous medication is needed. This reduces the risk of damaging the veins and infection. Receiving your intravenous medication in an outpatient clinic means that you will not need to stay in hospital if you are otherwise well enough to be discharged.

How should I look after my cannula?

The cannula is secured with adhesive tapes and covered with a see through dressing. This keeps it in place and allows the site to be easily seen. Minimise the risk of infection by avoiding touching the cannula or dressing. If you need to touch the cannula always clean your hands before and after touching your cannula. Make sure the cannula site stays clean and dry.

When washing you may find it useful to cover the cannula with a plastic bag in order to keep the dressing dry. Alternatively you can purchase a waterproof sleeve – details of such products are noted on the back page of this leaflet. It is unlikely that the cannula will become infected. However if you notice any redness or pain/pus or fluid around the cannula site please contact the clinic during office hours. If you have a high temperature (above 37.5) a shivery episode or flu like symptoms, attend your nearest Emergency Department.

What should I do if the cannula is accidentally dislodged?

Do not attempt to reinsert the cannula. If the cannula has not completely fallen out, carefully remove the dressing and gently pull the cannula out, cover the opening where the cannula was with gauze or clean tissue. It is normal for the site to bleed a small amount. Apply firm pressure for at least three minutes; keep applying pressure until the bleeding has stopped.

Once the bleeding has stopped, apply a small waterproof plaster to the site. You should then contact the Hospital for Tropical Diseases Clinical Nurse Specialist. You can dispose of the cannula with your normal household waste. If the bleeding does not stop after 15 minutes of applying firm pressure to the bleeding point, attend your nearest Emergency Department.

When will the cannula be removed?

It is safe to leave a cannula in place for as long as it is working well. There should also be no reports of pain or signs of infection. The duration that the cannula is left in place will be dependent on the treatment that you are having. If you have any concerns about your cannula, please contact the Hospital for Tropical Diseases on the numbers provided.

Further information

Have you travelled to a tropical country in the last 6-12 months and are you acutely unwell? You can be seen in our emergency walk-in clinic Monday to Friday 9am-4pm.

Our travel medicine service offers specialist travel advice including for individuals with complex health conditions. We offer this on a privately and via NHS referral basis.

Please contact: or 020 3447 7999 for more information about our services.