Preventing Surgical-Site Infections; Drugs Go Head to Head for Ischemic Stroke

TTHealthWatch is a weekly podcast from Texas Tech. In it, Elizabeth Tracey, director of electronic media for Johns Hopkins Medicine in Baltimore, and Rick Lange, MD, president of the Texas Tech University Health Sciences Center in El Paso, look at the top medical stories of the week.

This week’s topics include expanding the window for treating ischemic stroke, new agents for treating ischemic stroke, managing obesity in children and adolescents, and preventing surgical site infections.

Program notes:

0:36 Expanding the window for treating ischemic stroke

1:33 Complete recovery 10% more

2:33 Routine CT scanning

2:44 Comparing two agents to treat ischemic stroke

3:44 More in the reteplase group had hemorrhage

4:45 Dosing based on heart attack experience

5:24 Preventing surgical site infections

6:24 Up to a year after cardiac surgery

7:24 May look for staph

7:44 Interventions for high BMI in children and adolescents

8:46 Give a B recommendation to behavioral interventions

9:45 Don’t address bariatric surgery

10:45 Policy changes needed

11:45 Increased risk of early death

12:12 End

Transcript:

Elizabeth: Better agents for treating acute ischemic stroke.

Rick: Expanding the time to treat stroke.

Elizabeth: Treating childhood and adolescent obesity.

Rick: And preventing surgical-site infections.

Elizabeth: That’s what we’re talking about this week on TTHealthWatch, your weekly look at the medical headlines from Texas Tech University Health Sciences Center in El Paso. I’m Elizabeth Tracey, a Baltimore-based medical journalist.

Rick: I’m Rick Lange, president of Texas Tech University Health Sciences Center in El Paso where I’m also Dean of the Paul L. Foster School of Medicine.

Elizabeth: Rick, I’m going to turn it to you. Which of these would you like to start with?

Rick: Well, Elizabeth, there were two studies that had to do with stroke, so let me cover the first one. This is an article in the New England Journal of Medicine, a study that was done with the thought of can we increase the time to treat strokes. This study took place in China and they ask a simple question. We know if we treat strokes with tenecteplase, one of these agents that dissolves clots, in the first 4.5 hours you get a good result. We know that if you give a thrombectomy — and that’s done in other countries — you get a good result. But what about individuals that you do an imaging study and it looks like there is still brain that’s viable, but it’s been more than 4.5 hours outside the typical window? If you give tenecteplase, do you receive a good outcome?

Five-hundred and sixteen patients, the stroke that occurred more than 4.5 hours after the symptoms presented up to as long as 24 hours. But with a scan, it looked like there was still some part of the brain that was viable. What they discovered was that there was a higher percentage of individuals that had complete recovery with treatment with this agent than in those that didn’t receive it. In fact, it was about a 10% absolute difference, more individuals that had complete recovery.

Is there an increased risk of bleeding? There was a slight increased risk of what’s called symptomatic intracranial hemorrhage within 36 hours. It was about 3% for those that received the agent versus 0.8% for those that did not. This is important, Elizabeth, because about two-thirds of the patients that present following stroke present after that 4.5-hour window.

Elizabeth: Clearly relying on imaging in order to assess the viability of the brain tissue that’s impacted by the stroke. In the absence of the ability to do that kind of imaging, I’m wondering what’s the utility of this agent.

Rick: This study certainly doesn’t address that. Many of these studies in China were done in hospitals that were relatively rural and almost every hospital has a CT scanner. They showed it didn’t need any special equipment, just routine CT scanning. Now, again, these are hospitals that didn’t have access to thrombectomy and in that setting extending the time window further out isn’t really beneficial.

Elizabeth: Let’s turn then to the other article that’s in NEJM also looking at the management of stroke, acute ischemic stroke, which is of course what we’re talking about, the most common type. This is comparing an agent called reteplase versus alteplase [Activase], which is an agent we’ve had a lot of familiarity with in their efficacy and in these outcomes.

They had a total of 707 who were assigned to receive reteplase and 705 received alteplase. There is a difference in the administration. The reteplase is intravenous, a bolus of 18 mg followed 30 minutes later by a second bolus of 18 mg, and the alteplase is a single dose. They were looking at their efficacy outcome, excellent functional outcome, which is a score of 0 or 1 on the Modified Rankin Scale, and they also looked at symptomatic intracranial hemorrhage within 36 hours after symptom onset.

They did see the intracranial hemorrhage within 36 hours in 2.4% of the reteplase group and 2.0% in the alteplase. At 90 days, it was higher in the reteplase group, that’s 7.7%, versus almost 5% in the alteplase group. However, with regard to this functional outcome, an excellent functional outcome was achieved in almost 80% of the patients in the reteplase group and in just about 70% of those in the alteplase group. Their conclusion is that this agent is well worth trying.

Rick: This is nice for people who treat strokes. If you just give a single agent, it dissolves the clot, but a clot can reform and there may be some benefit towards giving an agent twice. There was an increased risk of intracranial hemorrhage, but it wasn’t symptomatic. That is they could see it on a scan, but it didn’t seem to worsen symptoms. That’s why the overall outcome was better with the double-dosing agent than the single-dosing agent.

Elizabeth: Right. One question I had about this, of course, is what would have happened if we had dosed alteplase in the same method as the reteplase was dosed?

Rick: The dosing is based upon what we use for treating heart attacks, and so the benefit of the alteplase supposedly is you just give one single dose. You don’t have to worry about a double dose. We don’t have any experience with double-dosing alteplase at this particular time, not with heart attacks or with strokes.

Elizabeth: I just wonder. The authors assert that we have a need for more of these agents and I’m just wondering, really, is that true or can we just use the ones that we have, but just use them differently?

Rick: I think you’re right. What we’re doing is we’re refining this. Trying to improve the efficacy without increasing the bleeding risk is where the sweet spot lies.

Elizabeth: Okay. Let’s turn to JAMA.

Rick: Preventing surgical-site infections. It’s actually one of the most common healthcare-related infections. It’s estimated that in the U.S., 3% of individuals who have surgery will have an infection at this site. By the way, nearly a quarter of patients in low- and middle-income countries will develop an infection at the surgical site.

Now, we know that we can prevent that by cleansing that area before we have surgery. The effectiveness of these preoperative skin antiseptics for preventing surgical site effects is well established. There is ongoing debate about what the best agent is. The two most commonly used are povidone-iodine, kind of this orange-brown solution, or chlorhexidine. This study attempted to address that in individuals who were undergoing either some type of abdominal surgery or cardiac surgery. Half the individuals are going to get the povidone-iodine. The other half are going to get the chlorhexidine.

How many people develop a surgical-site infection within 30 days after abdominal surgery or up to a year after cardiac surgery? They waited for a year because, remember, in cardiac surgery you oftentimes have sternal wires underneath the skin. The infection rate with either of these agents was about the same. It was between 5% and 6%, and there was no benefit of chlorhexidine over iodine. There were smaller studies and meta-analyses that suggest that chlorhexidine could be better, but it’s more costly. Oftentimes, it’s not available in low- and middle-income countries. Knowing that iodine works just as well, this will be a game changer.

Elizabeth: Too bad the iodine stains everything and is really so unsightly. You see it later and people still haven’t gotten rid of it.

Rick: Well, one of the advantages of the iodine over chlorhexidine is it’s kind of a slow release.

Elizabeth: It’s a little disconcerting to me that we still have a 5% to 6% rate of infection on surgical sites. What are your thoughts about that? Is there something else that might be beneficial or should we assess somebody’s flora before they undergo surgery?

Rick: That’s a great question. There are many sites that look, for example, meth-resistant staph and treat that with nasal applications. I wish I had an answer. You’re right, 5% is one out of 20 patients getting a skin infection. But overall, in terms of sepsis or deep infections, these are typically topical skin infections and not deep infections or sepsis. If there is a way to drive that even lower, that would be better.

Elizabeth: Remaining in JAMA then, let’s turn to the USPSTF’s [U.S. Preventive Services Task Force] recommendations relative to interventions for high BMI [body mass index] in children and adolescents.

This is clearly a public health issue. We have been identifying these increasing rates of obesity among children and adolescents in the U.S. for a while. In this analysis, the USPSTF say that about one in 5 children and adolescents between the ages of 2 and 19 years in the United States have a BMI that’s at or above the 95th percentile for their age and sex. It’s worse even than that among Hispanics and Latinos, Native Americans and Alaskan Natives, and non-Hispanic Black children and adolescents, and clearly something that sorts with lower income.

What the USPSTF does, of course, is take a look at all of the data that’s out there. What they conclude in looking at interventions, including behavioral counseling and pharmacotherapy, for weight loss and weight management in children is they can give a B recommendation to the notion that clinicians provide or refer children and adolescents 6 years of age or older with a high BMI to comprehensive intensive behavioral interventions. I really want to underscore this. These are ones that actually require greater than or equal to 26 contact hours. That is a lot of time in order to have this moderate impact or provide this moderate benefit.

They step away from the use of pharmacotherapy because they say that there is inadequate evidence. This in spite of the fact that we have reported on the use of these agents in children and adolescents and how that number is increasing in the United States. They do note that when pharmacotherapy is used that the recidivism is very high. Finally, the other place that they don’t address in here is bariatric surgery. To me, it’s sounding like they are requiring intervention that’s pretty labor-intensive and that takes a long time that still has a modest impact on weight for these kids, and they are stepping away from two other interventions that may be more helpful.

Rick: They did the original report back from 2017, so this is an update.

You mentioned that 26 hours of behavioral therapy — over the course of a year, by the way — that involved intensive training. It could be individual; it could be with a family. It almost always involved educating the parents by the way. They didn’t recommend pharmacotherapy.

There are currently four medications for 12 years and older who are obese, but none of these studies looked at long-term outcomes. You’re talking about putting kids on medications for years and we don’t know the long-term benefits of those. As you mentioned, when the medication stopped, the weight came back. This is more than just intervention at the family level. This is going to take changes at the local, state, and federal level, providing resources, policies, taxing food that doesn’t have much nutritional value, changing how we transport people, media, healthcare systems — this is going to have to be comprehensive.

Elizabeth: I would also note that the editorialist says major barriers to the implementation of this grade B recommendation include a profound lack of reimbursement and an absence of administrative clinical care and billing infrastructure to support startups, training, and implementing and sustaining this intensive, longitudinal, multi-component intervention. I mean, Rick, I just have to say I’m a little pessimistic about our ability societally to gear up to provide for this.

Rick: If we don’t, we’re going to increase the risk, when they reach adults, of continued obesity, diabetes, heart disease, stroke, cancer, and early deaths.

Elizabeth: My favorite thing here that the editorialist suggests is taxing obesogenic products, which I love. If we start doing that, maybe people will voluntarily turn away from a lot of those things.

Rick: It’s not just a single approach. It will be a societal effort to address this.

Elizabeth: On that note then, that’s a look at this week’s medical headlines from Texas Tech. I’m Elizabeth Tracey.

Rick: I’m Rick Lange. Y’all listen up and make healthy choices.