Intravenous Therapy (IV Therapy)

- Nurses place a small, thin plastic tube called a catheter directly into your vein. In order to place the catheter, we use a numbing spray to help minimize any discomfort

- Once our nurse accesses your vein, we remove the needle.

- The catheter remains inside you deliver your IV infusion.

- The catheter is attached to a bag, which contains your selected drip!

What’s in an IV Formula?

IV Fluids

There are a wide range of prepared sterile fluids which can be given via drip, and there are medical indications for choosing which one is best on an individual basis. The most common simple rehydration fluid is ‘normal saline’, a 0.9% solution of sodium chloride (salt) which is isotonic, meaning that it should allow the body to maintain a normal balance between the fluids within the cells and tissues.

When someone in the hospital requires IV fluids, they should get regular blood tests to monitor their kidney function and make sure the fine balance of electrolytes – the essential salts and minerals in the blood – stays within a healthy range. Different formulations of IV fluids can be chosen to maintain this balance – ‘Ringer’s’ or ‘Hartmann’s’ solution is a sterile liquid which contains small amounts of sodium, potassium, and calcium salts and is commonly given for fluid and electrolyte replacement.

Medications

Some medications come in a sterile injectable form either as a liquid or a powder that needs to be dissolved in a sterile liquid. Some can then be given neat (undiluted) or need to be diluted into a bag of fluid and given as a drip.

Blood Products

Blood transfusions are given via an IV line and may take the form of red cells, plasma, platelets, albumin or other components of blood.

Total Parenteral Nutrition

Some people require nutritional input which totally bypasses the digestive system. This can be for a variety of reasons and may be either short- or long-term. Sterile liquid ‘feed’ is available, known as total parenteral nutrition, or TPN. This contains a mixture of essential vitamins, minerals, proteins carbohydrates and fats.

Types of IV Therapy

IV treatments can be given as a drip, continuous infusion or a bolus (‘push’), depending on the type of treatment. Lots of different medications can be given intravenously.

IV Push

Some medications can be given as a ‘push’ or bolus. If they’re given through an existing IV cannula, it should be cleaned with antiseptic wipes designed specifically for that purpose, and flushed, usually with normal saline, before and after administration. This ensures that the line is clean and patent, so that the medication is able to go all the way through the tube and into the vein.

IV Drip

An IV drip traditionally refers to a fluid infusion of a set amount and duration. We call it a drip because there is a chamber at the top of the line where fluid drips through, and we can measure the drip rate to monitor the speed of administration. IV infusions which require a specific set rate more commonly go through an IV administration pump, which can be programmed to deliver a certain amount over a set period of time.

Both fluids and medications can be delivered by drip, and some medications need to be diluted in specific sterile fluids before they can be given.

Continuous Infusion

Some medications need to be continuously infused at a certain rate without a set endpoint. These should go through an infusion pump or a programmable syringe driver for accurate administration. Some continuous infusions can have a short gap while fresh medications are set up. Other medications need to be continuously infused without any break, and medical staff may need to ensure you have multiple points of IV access; this is to allow for a rapid changeover, and in case one IV cannula fails.

Types of IV Access

The locations and types of access points vary depending on the type of medication needed, the expected duration of treatment, and the individual. Some people have more difficult-to-access veins than others. Sometimes, ultrasound scans are used to help find a suitable vein. Occasionally, IV access may need to be gained in an operating theatre setting.

Peripheral Venous Cannula

An intravenous cannula is most commonly located in a vein in the hand or forearm, or occasionally the foot. This is known as a peripheral venous cannula, as it is in a peripheral vein; smaller and further from the heart. These types of cannulae are usually only kept in for up to around three days, and so other options may be considered for people who require longer-term IV therapy.

A longer-term option for intravenous treatment is a midline – these can stay in much longer than standard peripheral IV lines.

Central Venous Catheter

A central venous catheter (CVC), also known as a ‘central line’ is an IV line inserted into a much bigger central blood vessel. These can stay in longer than standard peripheral lines and therefore are often used when people need to have repeated IV therapy over a longer period of time, such as in some chemotherapy treatments, or in certain conditions where long-term IV antibiotic therapies are expected.

Central lines can also be used when access to peripheral veins is impossible. They can have multiple access lines within a single device so different medications can be administered simultaneously.

Central lines are also often used for administering medications that are likely to cause damage to smaller veins – the greater lumen and amount of blood pumping through big blood vessels means that there is a much lower concentration of the medication within a single vessel and reduces the risk of irritation and leakage.

Another type of central line is called a peripherally-inserted central catheter (PICC) line – this is a long line so the port is usually situated on the upper arm, but the medications administered still go into the large central vein.

Central lines can be used to take blood samples as well as deliver treatment.

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