When you are going to calculate drip rates, first you will need to know how to calculate flow rates. When nurses are required to use gravity tubing to run an IV, they are basically infusing an IV fluid without an electronic pump that controls the rate at which the fluid is infused. The benefits of doing it this way include the fact that you don’t need a pump, faster to set up, and it takes up less space. The down side of gravity transfusions is that they are less precise than using pumps, more dangerous and harder for beginners to master.
Over 95% of floors use purely electronic IV pumps purely because of their safety. Some units still use gravity infusions for basic, “safe” medications. Hospitals often have policies that forbid medications such as Potassium from being infused through gravity infusions because of their high risk of harm if given at the wrong rate.
An electronic IV pump will tell you exactly how fast it is infusing. If gravity infusions only consist of a bag, a line and an access port to the patient, how do you know how fast the fluid is infusing? That is why we calculate drip rates. Drip rates are how many drips of fluid you see falling through a chamber in one minute. Based on this number, we can see how fast it is actually infusing. Don’t be confused, here is how you do it.
3 Steps to calculate IV Drip Rates
The formula for how to calculate drip rates using this easy method is as follows:
The Flow Rate is simply how many millilitres per hour is the fluid supposed to me infusing. It is unique to every question. In order to calculate this, divide the volume to be infused in millilitres by the time in hours.
Step 2: The Drop Factor
What is a drop factor? A drop factor, also known as a drip factor, is a measurement used to determine how many drips of fluid are needed for the particular tubing being used to add up to 1ml. This is also unique to every question because different size tubing results in a different number of drops being required to add up to 1 ml. Thicker tubing requires less drips because the drops are bigger. Thinner tubing requires more drips to add up to 1ml because the drops are smaller. In each drip rate question, the “Drop Factor” of the tubing must be given to you in order to be able to calculate the question. The unit for drop factors is gtt/minute (gtt = drop).
Step 3: The Time Conversion:
The time conversion is unique to this method of calculating drip rates. It is basically a way of cancelling units out in order to get the correct result. The time conversion will always be 1 hour/60 minutes for every question you do.
The answer is obviously the desired drip rate. The desired drip rate describes how man drips per minute you are going to count falling through the drip chamber in order to have the correct speed of infusion.