SIS Podcast 11.2024

Hello, Behind the Knife listeners. I'm Nicole Petka, a general surgery resident at Emory University and one of the Behind the Knife Surgical Education Fellows. I'm here with Patrick Georgoff, trauma surgeon at Duke University. To start off, I want to set the scene for today's episode. Imagine you're coming in for morning rounds and you hear that one of your patients who's post op day five had a fever overnight.

The night team obtained CT imaging, which showed an intra abdominal abscess. You know that you need to start antibiotics, but what antibiotics do you choose? Do you find yourself always picking the same ones? What's the evidence behind your favorite antibiotic combination? We are going to cover all of this and more today as we go over the Surgical Infection Society guidelines on the management of intraabdominal infections.

2024 update. We have two special guests with us here today. First is Dr. Heather Evans. Dr. Evans is chief of surgery at the Ralph H. Johnson VA Medical Center. and a professor of surgery at the Medical University of South Carolina in Charleston. Dr. Evans attended her first SIS meeting in 2001 when she was a second year general surgery resident at the University of Virginia and just beginning her clinical research career in

surgical infections with Dr.

Robert Sawyer. Little did she know at the time, but she would go on to attend and present at every annual meeting of the SIS. Missing only one in 23 years and become the society's 44th president this year. Dr. Evans is a national leader in infection control research with a clinical expertise in surgical infections and a research specialization in the application of digital health solutions by leveraging multidisciplinary teams to improve post operative, post discharge care experience.

For over two decades, she has explored the application of technology, telemedicine and patient centered care to the diagnosis and treatment of surgical infections. Our second guest is Dr. Joe Forrester. Dr. Forrester is an assistant professor of surgery at Stanford University, the trauma medical director at Stanford HealthCare, and the medical director of Stanford's Chest Wall Injury Center.

He is also the associate chair of clinical affairs, where he helps oversee all of the department's quality improvement projects. Dr. Forrester received his medical education at the University of Virginia, received a master's of science from the London School of Hygiene and Tropical Medicine,

and completed his surgery residency and surgical critical care fellowship at Stanford.

Thank you for your time. Additionally, Dr. Forster was the first surgical resident accepted into the CDC's Epidemic Intelligence Service and served two years investigating outbreaks, including the Ebola outbreak in Liberia in 2014. Dr. Forster has been an SIS member since he was a medical student under the mentorship of Dr.

Rob Sawyer. He has stayed a member of SIS for the last 15 years because of high level science and camaraderie in the organization. He is the current SIS Therapeutics and Guidelines Committee Chair. Dr. Evans, Dr. Forster, welcome to Behind the Knife. Thank you so much. It's a great privilege to be here.

Thank you for the opportunity. All right, can you guys tell us a little bit about what the Surgical Infection Society is? It's funny listening to those introductions that we intersect in a couple of places. Both Dr. Forrester and I have a connection at the University of Virginia and Robert Sawyer has been a huge part of my career and a mentor for a long time.

I would say that For me, the SIS is really the embodiment of that mentorship connection that really has propelled a lot of people's careers. And if you look at how we're all related at one point, when I was working, I think I was the strategic planning chair at the time. I created a document that was actually a network diagram of where everybody's mentors and mentors.

mentees were in the United States. It was really fun to see how those connections had been made at this hub, the Surgical Infection Society. And so I would just say for young listeners that are in training right now, this is a wonderful organization where you can really have a connection with people that have a lot of enthusiasm for mentorship.

and also a lot of expertise in some really important things that all of our surgical patients face. Even those that don't get infection, we think about it all the time. We're always thinking about how we can prevent infection as well as how we can best treat

them. So I think for me, it's been just one of the greatest places in my career to, to make that network, to build those skills and, and to.

Become, you know, one of those people that is flying the flag of you know, limiting antibiotic duration and doing appropriate source control for patients. It's great to hear how the society has impacted both of your careers. I understand that the Surgical Infection Society also publishes updated guidelines for managing surgical infections.

Could you share with our listeners a little bit about the most recent publication? Yeah, the Surgical Infection Society Therapeutics and Guidelines Committee is at the forefront of driving best practice within the surgical infections and really the surgical community, really focusing on how we use antibiotics effectively to reduce morbidity and mortality for our patients.

This systematic review that we're going to be talking about today essentially covers the duration of time from the last guideline update, which was in 2016

to 2024. This guideline is essentially looking at the antimicrobial agents that we use for surgical infections, timing of those agents, routes of administration, and opportunities for de escalation.

We cover specific pathogens. treatment of specific intra abdominal disease processes and implementation of hospital based antimicrobial stewardship programs. Each recommendation that we publish comes with a strength rating of one, which is strong, or two, which is weak, and a grade for the quality of the evidence.

The grades are A for high, B for moderate, and C for weak. And the guideline document really highlights one of the essential services that SIS provides for the SIS members as well as the surgical community at large, which is to educate healthcare providers and the public about infections in surgical patients.

Yeah. Well, kudos to all of you and everyone who worked on the guidelines. They really are practical. They're useful. I really enjoy a lot reading it and learned quite a bit. And so to go through these guidelines, let's do some cases today. So we'll start off

with an easy one. Let's say you are the resident who is on consult services.

You mosey on down to the ed to see a patient. They have an intra abdominal abscess. You're getting them admitted. They've already been started on cefepime and flagyl and the ed team asks you if you want to add vancomycin. Heather, do you, what do you, what do you tell them? Well, I think one of the big questions that I have in my mind is like, what, what is the antibiogram of my hospital?

And am I worried about that? But if it's someone that's coming in from the outside, and this is a community acquired infection, that probably isn't quite as relevant. And so I'm not sure that Bancomycin really is something that would be important here for this patient's care. There certainly are some circumstances that if they came in from another health care facility, or they had been recently hospitalized, or if they were a long term antibiotic user, might think about that differently.

But I think someone that comes in from the community and has an intra abdominal

abscess that's just sort of spontaneous, usually these are like diverticulitis or even appendicitis is the most common intra abdominal abscesses that we're going to see. I think there's a very reasonable regimen without vancomycin.

Alright, your next consult's coming in. It's a 29 year old female. She has a history of HIV and she's not on antiretroviral therapy. She comes in with an intra abdominal abscess. She's septic and started on broad spectrum antibiotics. The unit pharmacist calls and recommends adding an antifungal agent.

When should an antifungal agent be used and what agent should you select? I'm happy to take this 1. You know, 1st, I think, but start by thanking our emergency department for this interesting consult and then moving on from there. You know, I think Dr Evans hit the nail on the head. I think when you're thinking about your patients, any patient with an infection, you're trying to.

As soon as we hear the call, we're trying to understand whether this is a high risk or a low risk patient. And, you know, in this patient with HIV who's septic, I'm starting to think this is a, you know, a potentially higher

risk patient. And in the guidelines, we lay out and differentiate the difference between a high risk and a low risk patient.

So when we're thinking about a high risk patient who's coming in with sepsis or in septic shock, we're starting to be a little bit more concerned about a broader range of pathogens. And you know, based on the most recent data that we reviewed for the guideline, for patients with high risk features, we would recommend using anigilofungin for empiric therapy.

Again, you know, that can be tailored down once the pathogen and the source is identified, but in the most recent guidelines with a grade of 1B, we'd recommend using anigilofungin. This is a new drug, for me at least, and can you expand a little bit on this medication? Yeah, so, anidulofungin essentially works on a different pathway than the azole medications, and so, was found to be more, or as efficacious as the azoles, and have easier dosing for these higher risk patients.

And are there any specific side effects that we need to be aware of? I would say that the most common side effects from

Anigula fungi are rash or hives or things like that, but they're typically fairly self limited and compared to other drugs like Amphotericin that has a lot of renal toxicity it's very well tolerated.

All right, and typically we think about fungal coverage when we think about upper GI type issues, especially a perforated peptic ulcer disease. Do the guidelines go into any details about separating upper GI versus lower GI sources? This most recent guideline document doesn't differentiate between the two.

Yeah, I think that the evidence of use of antifungals empirically in upper GI perforation is very mixed. A lot of the data has been extrapolated from other studies that are associated with candidiasis or, you know, DNA. systemic fungal infections. And so it's a little bit hard to tell exactly where we should be going with this data.

And nobody's ever going to do a prospective

randomized controlled trial of perforation with antifungals or no, I don't think. think. So I think that we're going to be stuck making these choices in the operating room. And I, I actually brought this up at our meeting this past year, because there was a presentation about this very topic.

There's some interest in this in our society, and there's a multicenter study looking at this. And I think one of the questions is, what do you do when you have someone that has like, tube feed peritonitis, right? Where this is just rife for developing a candidal infection intra abdominally. And we just don't really have an answer right now.

That's right. Yeah. We just went down the rabbit hole with this and it's not very satisfying. So we appreciate the SIS looking into this for us. And I want to point out that the guidelines also suggest against empiric antifungal therapy in lower risk patients. And so again, this, this question stem was a HIV positive patients, not on treatment.

And so there are specific high risk categories that are spelled out within the guidelines.

And so if you have any questions, encourage you to take a look at that. And then of course we're going to connect the guidelines into the show notes. All right, so let's talk about a very common issue appendicitis.

We have a 31 year old female presents with one day of right lower quadrant pain. She has a CT proven. Acute appendicitis. It is uncomplicated, meaning it's not perforated. And there's no fecal ith. So important kind of descriptors of dependecitis she's otherwise healthy. And she has a detailed discussion with the treatment team about different treatment options, including a laparoscopic appendectomy versus antibiotics alone.

She's very interested in avoiding surgery. The question then is how do we treat this patient? There's a lot of different trials that have shown that this is a viable treatment. You know, there is a failure rate approaching, you know, 30, perhaps 40 percent in some patients over multiple years when kind of taking all these trials and putting them together.

But when it comes to that patient who, you is well informed and makes that decision. How do we go about treating them? What antibiotics do we choose? What duration, oral IV, et cetera.

Well, first of all, I would say that I'm grateful that I had the opportunity to participate in the CODA trial when I was at the university of Washington.

I felt like I had equipoise going into that trial. And the question that I really wanted answered was if I am in the Himalayas and I have no access to a surgeon, is it okay for me to take antibiotics and treat my own appendicitis? I mean, I think that there are some circumstances out there where you'll be in a real life situation and you want to know the answer to this.

I think that when you when you think about treating with antibiotics. It's important to know that in the CODA trial in particular, they didn't say you should use this antibiotic regimen. They actually wanted to make it a pragmatic trial. And so as long as you were following the SIS slash IDSA intraabdominal infection guidelines, you were doing the right thing in terms of giving antibiotics.

So I think, you know, giving an oral

combination, anything within those low risk category for intraabdominal infection is completely reasonable. The nice thing about using moxifloxacin is it's a one agent. it's pretty well tolerated. It is effective and it's not dosed as frequently as some other antibiotics.

So I think it's a really good single agent drug for the problem. There is a randomized controlled trial that demonstrated that oral moxifloxacin was not inferior to giving IV ertapenem, which is another nice option. So you can give, erdapenem, which is a daily dose. And I think there have been some studies that have shown that you can actually give it as an outpatient for the treatment duration.

I think that would be a bit inconvenient for patients and the alternative of having an oral agent to complete your treatment. When you start with an IV dose of ertapenem seems like probably the best option because you know you're going to get 100 percent bioavailability or at least the best bioavailability possible with an IV

formulation right away at the initial time when you're making the diagnosis.

And then you can send the patient home on oral antibiotics. That was acceptable in the CODA trial. And there is some data that demonstrated that those patients that were sent home on oral antibiotics from the emergency department. Didn't have an increased risk of return to the hospital or treatment failure than patients that were admitted and cared for with IV antibiotics.

That's, that's huge to know, because that's kind of the sticking point, right? Do we have to admit this patient start IV antibiotics? Do we need to keep them for a day, two days? And then how long is the course thereafter? So knowing that a seven day course of oral moxifloxacin was not inferior to IV ertapenem, which we all kind of think of as that big gun antibiotic is, is fantastic to know.

To follow up on that then, Heather, do you give a dose of IV antibiotics to get things started and then write that script for moxifloxacin to go home? Yeah, maybe it sets my mind at ease more than it does the patient, but I think that's what I would want if I was the patient, just thinking that, you know, at least you're getting your

treatment started right away.

And then any other options besides moxifloxacin, which would be good for an oral course? I mean, I, I think Augmentin could be used in some cases, like it just depends on sort of what the community antibiogram is and your comfort level. You may have some treatment failures. I think, you know, Ciproflagyl is Also possible, but not very well tolerated.

If you've ever taken Flagyl orally, it's terrible. Not really my first choice. I really do like moxifloxacin, but there's some regions of the country where there's such high rates of resistance that that might not be acceptable or might not even be available in your formulary. All right, fantastic. Let's move on to something I was dealing with last night.

So we have this 31 year old female. She has appendicitis, decides to go for a lap api, and intraoperatively there's perforation. It's focally contained. You clean that area out, you do an uncomplicated

appendectomy, and then afterwards you're wondering how much antibiotics do I need to treat with? Do I need to give any at all?

What are the recommendations for post api treatment for perforated contained appendicitis? The recommendation for postoperative antibiotics agents for patients with adequate source control after complicated appendicitis, in this case, the patient that has a perforation, would be 24 to 48 hours, and a patient who has uncomplicated appendicitis, there's no need to treat for any duration afterwards.

But for this patient with a perforation, we're looking at 24 to 48, and this is based on several RCTs in addition to some of the subgroup analysis that was done from Stopit. Joe, I have a question for you. Would you ever, if, okay, let's say you had a perforated appendicitis like in this situation and you feel like you had adequate source control, would you send the patient home from the hospital?

Absolutely. Yeah. I think that's going to be the wave of the future. I think now that we see that it's safe and equally

efficacious to treat with shorter duration of antibiotics. And specifically as we see that oral antibiotics are equivalent to IV antibiotics. I think the pressure that we receive from hospital administration with respect to hospital capacity is going to force us in that direction.

And honestly, it's probably better for the patients to get them out of the hospital and in a healing environment faster. Yeah. And I like to say, like, if someone's going to develop a postoperative abscess, it's not like that antibiotic that you're giving a couple of days from now is going to prevent that.

And, you know, you need to take care of the patient that you have in front of you. If they develop an abscess, then you're going to treat that. You can't prevent it from happening, most likely. Right. So the data on this is a little bit mixed, right? We think that oral is fine. You don't need to keep them held hostage in the hospital giving IV.

And like you said, if they're going to develop that abscess, they will develop it. So how many days then if you're saying, well, I would like to give some antibiotics, I'm going to stick with oral. I'm going to discharge them from PACU or shortly thereafter. If you're going to write for oral, do you do a day?

Do you do two? Do you do three?

Based on the guidelines, I do no more than 48 hours. So, I mean, it's a grade 2B recommendation. So, you know, the data isn't as robust as a grade 1A or 1B recommendation, but it's pretty strong. Based on our review of the literature, we feel that 48 hours is, is more than adequate and safe and well tolerated.

Well, good. That's what we did last night based on that. We're very good at that. Well done. SIS for the win. You can follow that patient clinically. I do not think that there's any benefit in re scanning that patient empirically. Patient comes back and they have a fever, patient comes back and they have increasing abdominal pain, or they have redness at the site of their port incisions.

Anything like that, I would certainly rescan them, but I don't think that, that we should be empirically studying people just, you know, because we're worried about them. We should follow their clinical course. All right, moving on to our next case, we have a trauma activation. So this is for a 42 year old male.

He presents to the trauma bay after a gunshot wound to the abdomen, and he's taken emergently

to the operating room. When you arrive into the OR, your anesthesia team asks you your favorite question. What antibiotic would you like for prophylaxis? I would just say Anciflagil. That's my go to in this situation because Ancif is a really good drug for gram positive and gram negatives, but it doesn't have any anaerobic coverage.

And I know my anesthesia team has those drugs in the operating room. It's pretty easy to get that going. I think there are many other combinations or even single agents that you could use. You could use Erdapenem. If you had it, yeah, I think it's an interesting question because this is, I think there are two of the guidelines that came out that are going to be a little bit more controversial when it comes to implementing in practice.

This being 1 of them, I actually tried to roll this by our infection prevention committee and I got the, I got shot down 1st time around. So, so we'll see. It's a, it's an ongoing opportunity for

discussion. This is, you know, this is a new guideline that came out in 2016 based on 1 systematic review.

showing that erdapenem is efficacious. It's also nice because it's a single dose, but I think this one will be one that has the potential to change over time as people study it. That's the beautiful thing about guidelines is it, you know, it's a snapshot in time, but it's a snapshot that can change as the science changes.

Yeah, I think there's a couple considerations there that Heather you mentioned what's available, right? Especially if this is a an emergent case Antifragile are typically in the carts in most rooms. And so that's a probably the most important consideration but I do like to feel fancy sometimes if there is ertapenem is becoming more frequently available because it's linked into so many ERAS protocols and so if I do my elective case.

I got my bowel prep patient. I'm giving them erdapenem and there's no way they're going to get a postoperative infection. Well, why can't my, my GSW have that too? But I do look forward to more information in the following guidelines and with these trials coming our way. I just want to point out that I started using erdapenem because of the trial that Kamal

Atani was involved in and led many, many years ago now.

And he is the chief of surgery at the VA in Boston. and also past president of the Surgical Infection Society. So this club of SIS members is out there looking out for innovation and best practice for you. So a follow up question for our trauma patient. You were able to complete the case. You were able to close the abdomen.

How long would you continue antibiotics after a traumatic intra abdominal injury? This is a great question, and I think it's one where there's, it's really a data free zone at this point. I think that there is a lot of institutional practice, not a lot published on it, and not a lot of data. So this is really a call to action for the young listeners out there.

If you're looking for a research project, here's your opportunity. We don't really know what the infectious risk is with an open abdomen, with packs in the abdomen. Some people prescribe antibiotics, some people don't. It's a big opportunity for the intrepid young surgical trainee who wants to make their mark.

Now, Nicole, I think you said

this patient would be closed though. So let's say we have some small bowel injury, colon injury, you clean it up, put the patient together and close them. Joe, what would you call it? 24 hours, 24 hours, 24 hours. Max 24 hours. If I closed them at the time of the initial trauma operation, I would stop antibiotics at the time of the trauma operation.

Great. And that's a good segue to the next case because the next case is all about the stop at trial, right? So most residents now the stop a stop a stop at four days Everyone's got that on their minds and and quite frequently in a trauma patient like this one We just talked about who's closed right whose treatment is complete and source control is obtained.

They're not no up there or no panicking I still hear four days a lot, right? We're gonna continue for four days because they were contaminated. But how about we do this case and we can use this case to talk about the stop at trial and the more generalized idea of a infection that's been brewing in someone's belly for some time.

So 64 year old woman, type two diabetes, obese with perforated diverticulitis, a four centimeter abscess status post IR drain placement doing well. But the question is how long do you treat

this individual who's still in the hospital with. Antibiotics. Yeah. So I'll take this one and I'll just say that my, my gut is if you feel that you have source control, start counting four days from there.

That is really the magic number. Now, if you get the four days. and the patient looks terrible and they have not gotten better. You really need to reassess whether or not you actually have source control. I think that is the most important part of, of Stop It is that you may have treatment failure, but it's most often not an antibiotic treatment failure, it's going to be your source control failure.

And that's why we have to re image patients. We have to be vigilant. We don't send these patients home from the hospital immediately. We need to watch them, particularly if they're complicated. With a history of type two diabetes. Maybe you can add something else in there that would make you more worried about the patient.

But I think you know where it's

incumbent on us to monitor these patients and to see where their clinical course goes. You look for failure for their white count to resolve. You look for evidence of other evidence of systemic infection, even localized infection. If their drain stops working or if they end up having induration around the drain, all these things are questions and signs that potentially this could be getting worse and not resolving.

So you're watching the patient and you said, you know, for sure, four days starts ticking down once you think you have source control. And if everything goes well, you have source control. You do your four days and boom, the zosyn turns off on such and such date each, you know, each day you present it ticks down one day.

Great. But if that patient is not doing well. Then, that doesn't apply, right? And so, watching the patient is still, and always has been the most important thing. And this four days is not a you know, we don't follow that blindly. It really depends on how that patient's doing. Moving on to our next case.

This is a 63 year old gentleman and And he's undergoing a Whipple

procedure for a pancreatic head cancer. He had a preoperative biliary stent placed. And at that time they did cultures of his bile, which grew enterococcus. So knowing this information, how do you select an antibiotic for perioperative coverage and how long do you need to continue the antibiotic?

Yeah. Great question. And this is actually one of the recommendations where we think we have some of the highest level evidence when you have a preoperative culture that's positive, you have the ability to target your antibiotic therapy, which is important based on the data that we reviewed for this updated guideline, we would recommend continuing antibiotic therapy.

therapy for at least 24 hours from the index operation. And really, the goal is to prevent an organ space surgical site infection, which is where the data would suggest there's the most bang for the buck for that extended antibiotic therapy. But again, that's dependent upon there being preoperative cultures that are obtained so that you can target your antibiotic therapy accordingly.

Fantastic. All right, let's wrap it up

some quick hits. Let's start by talking about the initiation of antibiotics. of antibiotics and what our goal is in terms of timing. So certainly we want to do it as soon as possible, right? And we want to obtain source control more importantly, as soon as possible as well.

But there is some data that gives us some specific timeframes that correlate with worsening outcomes. What are those? There's a systematic review and meta analysis that demonstrates that if you delay antimicrobial therapy for more than six hours, it significantly increased mortality. And I think that study is actually pretty old now.

I would be really interested in seeing that repeated, but we've swung the pendulum away from running people over and tripping over them to get antibiotics into somebody within about five minutes of arriving in the emergency department, which was part of the surviving sepsis guidelines for a little while.

And I don't think that we're quite as dramatic about getting antibiotics started quite as fast, but within an hour is the recommendation in high risk patients with

sepsis. But I think that we, we've come back from the edge a little bit. I think that the, the emergency department was really getting to the point where they were delivering antibiotics so readily and so fast that we had to ask ourselves, are we really doing the right thing for patients?

Because some of those patients actually didn't have infection. They were just being treated because of their SERS response. So I think there is some balance there, but for somebody who's high risk at delivering antibiotics within an hour really is the goal. Fantastic. And then also in terms of source control, I think there are some recommendations that we have worked to obtain source control within 12 hours and low risk patients within six hours and high risk patients.

Joe, you want to share some take home points to kind of wrap this up for us? Yeah, definitely. You know, I think first, one of the things that we see on the guidelines committee is that antibiotics and antibiotic resistance really are constantly being developed and pathogens are evolving, so it's absolutely essential to review up to date guidelines, understand your local antibiotic gram,

be familiar with it, leverage your available antibiotics, and then come up with an informed plan for therapy.

It will be customized for every patient at every institution, but there's some best practices you can use. That's a generally shorter course. Antibiotics are for intraabdominal infections are well tolerated, but again, patient selection is important and understanding whether your patient is high risk or low risk in general.

Antibiotics can be stopped after 24 to 48 hours for complicated appendicitis after you have source control and then underscoring all of this is that we have this concept that time is life and that early appropriate antibiotic administration and early definitive source control. really are the two ingredients that are absolutely essential to securing a good outcome for your patient.

I just want to make sure all the listeners know that they're invited to the annual meeting of the Surgical Infection Society. This year it will be in Philadelphia, Pennsylvania at the Lowe's and it will be on May 13th and 14th. And we really hope that particularly residents who are interested

in surgical infections will submit an abstract and come to our meeting.

We're really looking forward to seeing you there. We cover a lot of great information today. I want to give a huge thank you to Dr. Forster and Dr. Evans for showing us how to apply these guidelines to clinical practice. To our listeners, thank you for tuning in and until next time, dominate the day.