A saline flush is the method of clearing intravenous lines (IVs), central lines or

arterial An artery () is a blood vessel in humans and most other animals that takes oxygenated blood away from the heart in the systemic circulation to one or more parts of the body. Exceptions that carry deoxygenated blood are the pulmonary arteries in ...

lines of any

medicine Medicine is the science and Praxis (process), practice of caring for patients, managing the Medical diagnosis, diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, ...

or other perishable liquids to keep the lines (tubes) and entry area clean and sterile. Typically in flushing an intravenous

cannula A cannula (; Latin meaning 'little reed'; : cannulae or cannulas) is a tube that can be inserted into the body, often for the delivery or removal of fluid or for the gathering of samples. In simple terms, a cannula can surround the inner or out ...

, a 5 - 10ml syringe of saline is emptied into the medication port of the cannula's connecting hub after insertion of the cannula. A 10ml syringe needs to be used to ensure correct pressure, whether you are giving 5ml or 10ml. Blood left in the cannula or hub can lead to clots forming and blocking the cannula. Flushing is required before a drip is connected to ensure that the IV is still patent. Flushing is also used after medications are delivered by the medication port to ensure all the drug is delivered fully. If multiple medications are given through the same line, flushing can be used in between drugs to ensure that the medicines won't react. This is especially important if complex regimes of intravenous medication is used such as in

chemotherapy Chemotherapy (often abbreviated chemo, sometimes CTX and CTx) is the type of cancer treatment that uses one or more anti-cancer drugs (list of chemotherapeutic agents, chemotherapeutic agents or alkylating agents) in a standard chemotherapy re ...

. Flushing with saline should be painless if the cannula is in its proper place, although if the saline is not warmed there may be a cold sensation running up the vein. A painful flush may indicate tissuing or

phlebitis Phlebitis (or venitis) is inflammation of a vein, usually in the legs. It most commonly occurs in superficial veins. Phlebitis often occurs in conjunction with thrombosis (clotting inside blood vessels) and is then called thrombophlebitis or ...

and is an indication that the cannula should be relocated. Solutions other than normal saline may be used.

Heparin Heparin, also known as unfractionated heparin (UFH), is a medication and naturally occurring glycosaminoglycan. Heparin is a blood anticoagulant that increases the activity of antithrombin. It is used in the treatment of myocardial infarction, ...

ised saline may be used in flushing arterial lines, to prevent clotting and blockage of the line. When syringes are used to perform a saline flush, it is important that the syringe not be reused for multiple patients, even though direct contact with the patient does not normally occur. In angiography, a saline flush is used to improve the dispersion of contrast media before imaging, This can prevent streak artefact due to concentrated bands of contrast media in the superior vena cava and brachiocephalic vein. Flushing can also increase hydration within contrast media, thus reducing the risk of contrast induced nephro toxicity.

References

Intravenous fluids Enteral feeding {{Treatment-stub