Surgical site infections are one of the most common reasons for unplanned readmission after surgery. This article will help you successfully implement a plan with your surgical team to prevent the hassle and discomfort of readmission.
The 18th century Scottish poet Robert Burns’ famous quote was about a mouse but it’s pretty applicable to surgery:
The best-laid plans of mice and men often go awry.
Suppose you’re one of the 700,000 Americans each year having your knee replaced. A week goes by and your knee starts getting painful, hot, and swollen. You go to the emergency room, where they take off the dressings and you see your knee looking like this:
Photo credit: Evan Watts, M.D. ( https://www.orthobullets.com/recon/5004/prosthetic-joint-infection)
You kind of recall one of the many things your surgeon previously mentioned: that there’s always a small chance of infection after the operation. An infection after surgery is called a surgical site infection (SSI).
About SSIs and How to Prevent Them
SSIs show up days or weeks after an operation and are one of the most common reasons patients get readmitted to the hospital. Unplanned readmissions are expensive and cause a lot of anxiety, inconvenience, pain, and potential harm. Unplanned readmissions are something every hospital administrator stays up at night worrying about.
Some operations such as a carpal tunnel release of your wrist or cataract surgery carry an extremely low risk of SSI. Other operations, such as the removal of a portion of large intestine for colon cancer or an appendix for appendicitis, carry a much higher risk.
In almost all cases, SSIs are considered potentially preventable and surgeons do everything in their power to keep them at bay. Some of the things your surgeon might do to prevent an SSI are:
Use special sutures that kill bacteria
Give antibiotics for higher risk surgeries before incision is made
Have you shower twice the night before your operation with a chlorhexidine wash
SSIs after placement of a mechanical object (e.g., knee or hip replacement) are notoriously difficult to treat and may require removal of the device. And as it is in every other aspect of care during the perioperative period, it takes a team effort to beat SSIs.
Everyone has to be on board and committed — it’s hardly sufficient for just the surgeon to be your advocate.
How You Can Be an Integral Part of the Team
But what can you personally do? Can you somehow be part of your team? In this case the same theme reappears — namely, the more you know about something, the more helpful you can be. And that’s certainly true for SSIs, which many persons believe are in great part preventable. When a wound is opened for surgery, many things will inevitably cause wound contamination: bacteria from the skin, the ambient air, the surgeon’s gloves, the intravenous lines, etc.
All surgical wounds get contaminated. (Photo by Kristin Brown on Unsplash)
So what happens to cause or prevent an SSI once the bacteria are sitting there in the wound? First of all, the fewer bugs there are, the better. A great big group of bugs is certainly harder to kill than a small gang, which means that every source of contamination should be carefully vetted and marginalized.
In terms of your skin, following exactly the surgeon’s instructions before surgery — especially with respect to showering — is very beneficial. But for the bugs that remain, it’s up to your own body to defend things.
The body’s immune system uses a variety of methods to kill bugs — the most important of which is cell destruction by a white blood cell called a neutrophil. Neutrophils kill by “oxidative killing,” which means they need oxygen to do their job. Generally, the more oxygen available in the tissues for the neutrophils to use, the better. At the same time, cold weakens the effectiveness of the neutrophils. So does stress. And in terms of the bacteria, many of them are killed if there’s an antibiotic lying in wait in the tissues when the wound gets contaminated.
Methods to prevent SSIs fall into three broad classes of methods:
Decreasing bacterial load or number of bugs (in medical terms this is called “decreasing the bacterial inoculum”)
Weakening the bugs
Enhancing the body’s bug-fighting ability (in medical terms, its immune response)
The Multiple Strategies Method
The more interventions or efforts you make to reduce SSIs, the more you will be rewarded. This might be called the “multiple strategies method”— basically throwing everything but the kitchen sink at the problem.
If we look at the three broad classes of methods to reduce SSIs and then how each of these might be implemented, we come up with a helpful little list that will help guide you with various care processes to prevent surgical site infections:
Decrease Bacteria Load
The entire team needs to be obsessive/compulsive about sterile technique.
The patient must take chlorhexidine showers the evening prior to surgery.
The anesthesiologist must use alcohol swabs or disinfectants on each IV port before injecting medicines. Research studies at Dartmouth have shown an alarming number of IV ports where medicines get administered are contaminated.
The anesthesiologist must maintain a clean anesthesia workspace. Again, studies at Dartmouth have shown the anesthesia workplace is often contaminated.
The entire team must minimize Operating Room traffic (the fewer people in and out of the room — especially for hip and knee replacement surgery — the better)
Weaken the Bugs
The anesthesiologist must give a weight-based dose of antibiotic at the proper time so that the amount of antibiotic in the tissues is at its greatest when surgical incision takes place. Also, larger people require larger doses of antibiotics (weight-based dosing). Many large people with BMIs above 40 aren’t getting sufficient levels of antibiotics in their tissues.
Supercharge the Body’s Bug-Fighting Ability
The entire team must keep the patient warm (cold cripples the immune system).
For diabetics, the patient and team must his blood sugar within reasonable limits. Whenever possible, have the patient lower his hemoglobin H1c down to < 7 prior to surgery. Too much sugar weakens the immune system.
Neutrophils (white cells) need oxygen to kill bugs. High levels of oxygen in the tissues are a well accepted method to reduce SSIs in colon surgery (a surgery with a very high risk of SSIs). Although the proof is not as strong for other surgeries, the team’s use of higher levels of oxygen is likely beneficial and there is no risk associated with using more oxygen.
Being a heavy smoker will weaken the neutrophils, so patients must refrain from smoking.
The oxygen in tissues can also be increased when the patient’s carbon dioxide levels are mildly elevated, and this can readily be done by the anesthesiologist. Available experimental and clinical evidence demonstrates this technique improves tissue blood flow and tissue oxygen levels and may decrease SSI risk, but this is unproven. However, there is no risk and certainly numerous potential benefits of using a mildly elevated carbon dioxide level.
The anesthesiologist can decrease the stress response to surgery by using spinal and epidural anesthesia. Studies on knee replacements have shown a large decrease in SSIs using this type of anesthesia.
There are many more care processes for infection prevention, but they all fall into the aforementioned three classes. One of the foremost experts in the prevention of SSIs, Dr. Charles Edmiston, presented a table showing that the greater the number of care processes put into place, the lower the infection risk. This is clearly a team approach and each member of the team has to buy into the mission to reduce SSIs:
It’s also interesting that whether or not a SSI will occur is pretty much determined during what is called “the decisive period” — the interval between surgical incision and surgical completion. Therefore, it’s really important for the entire team to bring their “A-game” to the intra-operative period. In other words, you can’t do much to prevent an SSI once the wound has been closed.
N.O. B.U.G.S.
When I was at the Naval Hospital in San Diego, one way I taught residents to remember some of the ways SSIs may be reduced was through the “NO BUGS” Mnemonic:
Normal temperature (don’t let the patient get cold as this greatly increases infection risk)
Oxygen (higher oxygen levels improve the ability of neutrophils to kill bugs, and this technique is well accepted in colorectal surgery; other surgeries are still controversial)
BMI (body mass index is a measure of how heavy people are, and since antibiotics should be weight-based, the greater the BMI, the greater the amount of antibiotic required; elevated BMIs increase SSI risk)
Underventilation (which is the act of slightly increasing the carbon dioxide in a patient’s blood to release more oxygen to the tissue; there is theoretical and some clinical evidence available that strongly suggest this technique is helpful — it’s definitely not harmful and should be used when possible)
Glucose or blood sugar (diabetics are well known to have a greater risk of infection after surgery and the blood glucose should be kept below 200 to optimize the body’s immune response; more importantly, in terms of sugar control is the hemoglobin H1c — a kind of 2–3 month long record of the body’s sugar level; ideally, to reduce SSI risk, H1c should be below 7)
Shower, skin (anything the patient or team can do to reduce the bugs on the skin before incision is beneficial and the use of a chlorhexidine shower twice the night before surgery has been shown to be advantageous, too)
No one desires an unplanned readmission after surgery, but a successful implementation under a team approach can prevent such a painful inconvenience. The entire surgery team needs to drink the punch — not just the surgeon, which is how it used to be. And you, the patient, are an integral part of the team when it comes to your own operation and fighting the battle against bugs. By properly preparing and working together, you can save yourself from unnecessary pain and suffering!
Additional Reading
Here are some great references if you’d like to learn more:
https://www.dhs.wisconsin.gov/publications/p01715.pdf
https://www.dhs.wisconsin.gov/non-dhs/dph/edmiston-ssi-91515.pdf