The Main Types of Bloodstream Infections

We’re going to talk a little bit for the next few minutes about blood stream infections, BSI, blood stream infections. And blood stream infections over the last few decades have actually been on the rise, with more than 350,000 reported over a year’s time, and blood stream infections are defined as pathogens in the blood found in patients that have been in the hospital for more than 48 hours. So, they’ve been in the hospital for more than 48 hours, there’s pathogens found in their blood, and more than 350,000 of these cases of blood stream infections are found per year, and it is on the rise, has been over the last several decades. Now, when we think about blood stream infections there are two types to be kept in mind when they are discovered in the blood of the patient.

First is primary infection. This basically is an infection in the blood that has been introduced there through an intravascular device. So it may be related then to the IV or something that is intravascular and has been contaminated and therefor introduced the pathogen to the blood directly. This is primary infection.
The second type of blood stream infections is a secondary infection, meaning that there is infection elsewhere in the body – urinary infection or wound infection that is then spread systemically and ends up in the blood. And it needs to be determined which it is, if it’s a direct infection, primary infection, introduced from outside through an intravascular device, or perhaps it’s a secondary infection that’s been spread systemically because of infection in another part of the body, and that clearly needs to be determined first.

When you’re diagnosing a blood stream infection, the following four things need to be kept in mind:

1) First, skin preparation. It’s extremely important that there must be adequate measures taken to prevent contamination of the sample. So when you’re taking the blood sample, please prepare the skin properly ahead of time to avoid contaminating the sample and therefore skewing your results or perhaps getting a false positive. So to get a proper diagnosis, remember proper skin preparation.

2) Two, blood volume is the second thing you need to think of here. Make sure you have a sufficient quantity to test and find the pathogens there. You need to ideally keep it between 10 and 20 ml in order to detect low concentrations of organisms.

3) Three, you need to think about timing. As soon as there are symptoms of a blood stream infection, you need to immediately get the sample in order to test it so that you can begin treating and dealing with it right away. So timing is critical. As soon as symptoms appear, you need to act as soon as possible.

4) And then finally, venipuncture. You need to draw your sample not from the intravascular catheter that’s already present which may actually, because of a primary infection, be the very cause of the blood stream infection, but you need to go peripherally to obtain your sample.

So, in getting a proper diagnosis, prepare the skin, have the proper volume of blood to test, make sure you act right away, get the timing right, and then when you do draw with the venipuncture, make sure you get it peripherally and not from an intravascular catheter, which once again may be the cause of the blood stream infection.

Keeping these things in mind will be important for you to not only properly understand blood stream infections but to diagnose them properly.