By Thomas E. Serena, MD, FACS
Conceived in the operating theater and born in the home, surgical site infections (SSIs) reach maturity in the outpatient wound clinic. The woundologist, whether surgically trained or not, must understand the prevention and treatment of SSIs and wound dehiscence. For the past two years I have had the honor of giving the SSI lecture for the WoundSource Practice Accelerator™. This year listeners had more questions than I could answer on the call or address individually. I decided to dedicate this blog to the most frequently asked questions from the October presentation.
Frequently Asked Questions on Surgical Site Infections
Question: What is the best post-operative dressing?
Answer: Based on the available literature, there is no best dressing. Comparative effectiveness trials do not exist. However, the characteristics of an ideal post-operative dressing include the following: permeability to allow for gas exchange; impermeability to microorganisms, thus preventing exogenous sources of contamination; antimicrobials to prevent bacterial growth within the dressing; and the ability to provide an insulating effect to maintain a temperature of approximately 37° Celsius to promote a moist healing environment. It is definitely not gauze.
Antibiotic Stewardship in Surgical Site Infections and Wounds
Question: In wound clinics, culture swabs are often done as soon as a patient enters for a quick evaluation of bacterial burden. Biopsies take time to receive results and are uncomfortable for patients. Do you recommend biopsies be performed on everyone, or should we continue with cultures for basic evaluation?
Answer: Abandon the routine use of swabs! Swab cultures do not accurately measure the bacterial load in the wound bed and lead to the indiscriminate use of antiseptics and antibiotics. In the SerenaGroup® antibiotic stewardship program, swabs have been eliminated unless there is frank purulence. If there is a concern over the bacterial burden in the ulcer bed, fluorescence imaging will detect moderate to heavy bacterial burden. If infection is suspected, tissue can be sent for a quantitative biopsy or a swab for polymerase chain reaction testing. Finally, I do not recommend the routine use of swabs or biopsies simply to gauge bacterial burden.
Question: There are papers that discuss biofilm within surgical wounds and bacterial adherence to foreign bodies such as staples and sutures leading to biofilm within four to six hours. What are your thoughts on this, and does biofilm formation factor into your management techniques?
Answer: You are correct. Biofilms form rapidly on foreign bodies in infected wounds. For this reason, the surgeon or wound clinician must remove any foreign material. Over the years I have extracted hundreds of sutures from non-healing wounds, after which the wounds healed rapidly.
Question: I have seen a lot of abdominal incisions with staples open to air. What do you think of this practice?
Answer: The general rule is to cover the incision for at least the first 48 hours. It can then be left open to the air. If there is no drainage, the dressing can be removed. The dressing is left on for a longer period of time in wounds that have heavy exudate and in certain locations such as the groin. The use of incisional negative pressure is another option for groin incisions, abdominal procedures in obese patients, and hip fracture repair.
Question: What is your take on soaking foams with antimicrobial fluid as an active bacteriostatic dressing?
Answer: I have heard of this practice; however, there is no evidence for it. In our clinics we strive to follow evidence-based guidelines. I cannot recommend "foam-soaking" until there is a clinical trial demonstrating a benefit.
Question: I work in a CVTS post-operative clinic. You mentioned the use of silver dressings immediately post-operatively, but as most surgical wounds are noted in the clinic setting, how does one determine the best wound care dressings for wound dehiscence? Is there a guide online for this information?
Answer: True! Most wounds following an SSI occur at home and are seen in the surgeon’s office or wound clinic. The Association for Advanced Wound Care (AAWC) has developed guidelines for the treatment of surgical wounds available to members on the AAWC website; however, the treatment follows the same principles applied to most wounds seen in the wound clinic. If you would like to learn more about basic wound care, I am happy to suggest a wound care conference that will meet your needs. WoundSource is holding a virtual conference if you are unable to attend an in-person meeting. Please feel free to send me an email at firstname.lastname@example.org.
Question: What about the use of advanced wound care dressings post-surgically for high-risk patients?
Answer: Please see my answer above on what I see as the ideal post-operative dressing. However, it must be noted that the major published reviews and guidelines do not recommend advanced wound care dressings for the prevention of SSIs. The following is a direct quote from the recent published World Health Organization (WHO) SSI prevention guidelines, "The panel suggests not using any type of advanced dressing over a standard dressing on primarily closed surgical wounds for the purpose of preventing SSI." I believe we need more research on post-operative dressings.
Question: There is a great deal of information on the Web about hypochlorous acid and its role in wound care. Can you comment on this solution?
Answer: Hypochlorous acid is a non-toxic antiseptic frequently used to cleanse wounds. Several of the SerenaGroup® centers use it routinely; however, more research on the in vivo antimicrobial effect is needed. In addition, none of the antiseptics have demonstrated improvements in wound healing with routine use.
Question: How do we raise more awareness with our clinical "woundologists" to start thinking about bacteria and how important they are in wound care?
Answer: There is no doubt that a moderate to heavy bacterial load in an acute or chronic wound impedes healing. Reduction in bacterial burden is a basic pillar of every wound algorithm. The answer is education. In 2019, the AAWC held two conferences dedicated solely to the problem of bacteria in wounds. These conferences were a huge success. We need more conferences that examine the latest evidence. Join us at Wound Week, April 16-19, 2020 in Milwaukee for an in-depth look at biofilms and bacteria in wounds. Contact me for additional conferences that will take more than a cursory look at this problem (email@example.com).
I want to thank everyone for their questions. Unfortunately, I could not answer them all.
About The Author
Dr. Thomas E. Serena is the Founder and Medical Director of The SerenaGroup®, a family of wound, hyperbaric and research companies. Dr. Serena has been the lead or Principal investigator in over 100 clinical trials, including gene therapy, antimicrobial dressings, growth factors, topical and parenteral antibiotics and CTP therapy. He has more than 200 published papers and has authored several medical textbooks and numerous book chapters. He has given over 1000 invited lectures throughout the world. He has been a member of the Board of Directors of the Wound Healing Society and served two terms on the board of the Association for the Advancement of Wound Care (AAWC) and is now the President.
The views and opinions expressed in this blog are solely those of the author, and do not represent the views of WoundSource, Kestrel Health Information, Inc., its affiliates, or subsidiary companies.