How can wound infection be prevented?

We’ve just discussed how to diagnose a wound infection, and we mentioned about wound swabbing. I’d just like to take a few minutes now to explore wound swabbing in a little more detail, mainly because we find a lot of practitioners or patients will say, I need my wound swabbing to see which antibiotics I need. It isn’t always necessary to take a wound swab, as we discussed earlier.

Lipsky et al has actually said that there’s generally no need to culture a clinically uninfected wound, as they don’t require antimicrobial therapy, and this may sound common sense, but still, there seems to be some sort of ritualistic practice in some areas where people say, I need to take a wound swab every time I take the wound dressing down just to check there’s no infection there. This isn’t required. Only clinically infected wounds should be cultured and preferably by obtaining tissue by curettage or biopsy, but we know not everybody is trained to be able to do this, but that does provide a more sensitive and specific result than swabbing.

So if you have to swab, only swab if the wound is clinically infected. You need to know which antibiotics will help to manage that wound infection. A wound swab should not be undertaken every time a wound dressing is taken down and the wound itself is assessed. So prior to wound swabbing, all wounds should be cleansed and debrided prior to taking the wound swab. Often, staff think they need to take the wound swab from the area that has the most exudate and looks the dirtiest, but no. You need to take the wound swab from the cleanest area. So please clean the wounds as your normal protocols prior to taking that wound swab.

You can collect a specimen for culture before starting antibiotic therapy, and if there’s any signs of systemic inflammatory response syndrome, blood culture should also be ordered, as well as taking that wound swab. And if you do suspect it’s osteomyelitis, so particularly important in orthopaedic patients, then you may need to get a bone culture. So this will have to be ordered. When taking a wound swab, please remember, it doesn’t confirm or deny infection. The purpose of taking the wound swab is to reveal the type or the number of bacteria on the wound surface and to ensure the correct antibiotic-sensitivity testing is undertaken and then correct and appropriate antibiotic therapy commenced.

And remember, results should be reviewed in context of the clinical symptoms, never in isolation. And what we mean by this is, is the patient pyrexial? Do they feel unwell? Is there excess exudate coming from the wound? Or similarly, does the patient say, yes, I may have a highly exuding wound, but I generally feel well.

You may have been in different clinical areas and been shown different techniques when taking a wound swab. However, the most effective technique is the Levine technique and not the Z-swab technique. People may not be aware what the Levine technique is, but we’re now going to look at it in a little bit more detail.

So for the Levine technique, you should cleanse and debride the wound prior to undertaking wound swab, and remember to get permission from the patient before taking that wound swab, explain to them why you’re taking it, what the purpose is, and roughly how long it’ll be before the results come back so they don’t panic about what’s happening. Cleanse the wound using warm, normal saline, and debride any non-viable tissue and then cleanse the wound again. Moisten the culture tip with sterile saline, especially if the wound is then quite dry, and obtain a specimen from the cleanest area. If possible, do not obtain it from anywhere where there is sloughed or necrotic tissue.

Just inform the patient then of exactly what you’re going to do prior to undertaking the wound swab and explain that it may cause some discomfort. Some patients can be very sensitive, remember, when touching the wound area. Place the swab directly into the wound, press, and rotate. Use the sterile technique and then put it back into the container. What may then sound like common sense is please ensure that the container is labelled correctly, patient’s name, patient’s hospital number, and that the tests required are documented clearly. Also identify where the site of the wound is and when the wound swab was taken and give as much history as possible for the microbiology team to be able to see.

And then apply your dressings as appropriate and send the wound swab off. What’s important as well, we’ve talked about hand hygiene and the essential nature of this and everybody being able to know how to wash their hands correctly. But again, when cleansing the wound, either after taking a wound swab or just normal reassessment of the wound and reapplication of wound dressings, there should always be a risk assessment conducted prior to performing any wound-management procedures, asking the patient how they feel, looking at the environment, ensuring it’s safe, not changing the wound dressing if there’s cleaning going on in the area. Use sterile kit gloves and equipment when touching the wound directly, and obviously ensure your hands are clean.

It may be necessary to use personal protective equipment, such as masks and gowns, but again, look at your local policies and guidance, because they may change slightly between different clinical environments. Ensure that you dispose of sharps in the correct way and in a safe way, and make sure you’ve got a good, clean working area where you can walk around, and there’s no slip or trip hazards and that prior to undertaking the wound dressing change, make sure the patient is comfortable, they’ve had any analgesia prior to undertaking this procedure, and that they’re happy giving your permission for you to undertake this procedure.

And as you can see from this figure, it quite clearly identifies the steps for an aseptic technique, from washing your hands to preparing the equipment to disposing safely of the dressing and any sort of paraphernalia that you may have been using.