Episode #268 Beyond the Vein: The Dangers of Infiltrated Muscle Relaxants

Hello and welcome back to the Anesthesia Patient Safety Podcast. My name is Alli Bechtel, and I am your host. Thank you for joining us for another show. We will be talking about how to keep patients safe following  IV infiltration of neuromuscular blocking agents and we will be hearing from the team responsible for the latest APSF article.

Before we dive further into the episode today, we’d like to recognize Preferred Physicians Medical, a major corporate supporter of APSF. PPM has generously provided unrestricted support to further our vision that “no one shall be harmed by anesthesia care”. Thank you, PPM – we wouldn’t be able to do all that we do without you!”

Our featured article today is “Treatment and Complications of IV Infiltration of Neuromuscular Blocking Agents” Rangrass and colleagues. To follow along with us, head over to APSF.org and click on the Newsletter heading. The first one down is the current newsletter. Then, scroll down until you get to our featured article today. I will include the link in the show notes as well.

There are over 150 million peripheral intravenous catheter insertions placed in the United States every year. How many have you placed today or this week? It is the most common invasive procedure performed in hospitals. There are several important complications of this procedure including nerve injury, vascular injury, and infiltration. IV infiltration is the unintended administration of any medications or fluids into tissues surrounding the catheter. Did you know that infiltration occurs in almost 14% of peripheral IV catheter insertions. This is a big threat to anesthesia patient safety. Risk factors may be related to the equipment and care-related factors. Many IV infiltration events can be managed conservatively, but severe cases can result in severe consequences including tissue injury requiring surgical intervention, specialized wound care, persistent pain, or loss of limb function.

When an IV infiltrates in the operating room, there are additional important complications to consider including intraoperative awareness, failed resuscitation, or compartment syndrome. What about when the IV infiltrates following neuromuscular blocking agent administration? This can have additional consequences. Infiltration of nondepolarizing neuromuscular blocking agents puts patients at risk for subsequent resorption and recurarization leading to muscle weakness, respiratory insufficiency, and postoperative pulmonary complications. Patients with decreased liver and kidney function may be at even higher risk following neuromuscular blocking agent infiltration. For this complication, we don’t have guidelines for the management and it can be difficult figure out how to keep patients safe especially during same day surgery and higher risk patients.

Before we go further into the article, let’s here from one of the authors:

[Andrea Vannucci] “ Hi, my name is Andrea Vannucci and I am a clinical professor of anesthesia and Vice Chair for Quality and Safety at the Carver College of Medicine at the University of Iowa in Iowa City, Iowa.”

[Bechtel] I asked Vannucci what got him interested in this topic? Here is his response.

[Vannucci] “Perioperative intravenous infiltration is a common complication that can pose significant patient safety risks. The severity of these risks depends on several factors, including the physical chemical properties of the infiltrated substance, the time elapsed before recognition and intervention, and the pharmacologic actions of the drug involved.

A particularly concerning scenario involves the extravasation of neuromuscular blocking agents. These agents may be reabsorbed unpredictably, potentially leading to delayed or recurrent neuromuscular blockade. These can impair critical functions such as swallowing and respiratory muscle activity, posing a risk of airway and ventilation compromise after extubation.

Currently, there are no formal guidelines for the management of, uh, neuromuscular blockage agents externalization. In response to this gap, our team sought to develop a clinical approach grounded in general medical principle, and informed by the best available evidence from the anesthesia literature.”

[Bechtel] I also asked Vannucci what’s next for your research and projects? Let’s take a listen now.

[Vannucci] “ I am interested in developing and communicating strategies that can help clinicians and organizations identify and manage high risk situations. My current projects include enhancing event reporting systems, developing EMR, integrated, perioperative end of tools and evaluating video endoscopes to guide device selection for specific clinical scenarios.”

[Bechtel] Those are some very exciting projects and we will have to stay tuned for the results.

Let’s return to the article now. There is a study from 30 years ago that evaluated subcutaneous administration of Succinylcholine and found that patients receiving equal doses of subcutaneous succinylcholine had incomplete maximum depressed twitch height, prolonged onset time for paralysis, and shorter recovery from paralysis time. Looking at inadvertent subcutaneous non-depolarizing neuromuscular blocking agent administration, there can be pronged onset and duration of paralysis with significant variability. This is due to the unpredictable movement of this drug from the subcutaneous tissue to central circulation. There is an increased risk for recurarization after rocuronium administration into subcutaneous tissue following IV administration of reversal agents. This is what the scenario of secondary recurarization looks like: Patients were administered additional intubating doses of rocuronium about 0.6-1.2mg/kg ideal body weight after an initial infiltrated administration combined with suboptimal dosing of reversal agents.  While sugammadex may be used to successfully reverse neuromuscular blockade following infiltrated rocuronium administration, there is a risk for recurarization due to the short half-life of sugammadex, only 2 hours, and the molar 1:1 binding ratio. For patients with mild renal insufficiency the half-life of sugammadex is longer at about 4 hours and up to 19 hours in severe renal failure so this may in theory be a benefit to patients following infiltration of rocuronium as long as the binding capacity is not full.

Before we get to the management of neuromuscular blocking agent infiltration, let’s here from another one of the APSF authors.

[Karolina Brook] “ Hi, my name is Karolina Brook. I am an anesthesiologist and director of Quality and Safety at Boston Medical Center in Boston, Massachusetts. I’m also the ASA Committee for Patient Safety and Education Vice Chair.”

[Bechtel] I asked Brook what got her interested in this topic or area? This is what she had to say.

[Brook]   “In my department, we collect data on what we call unanticipated events. This includes adverse events as well as near misses, but also far more expansive events. And one example of this is actually IV infiltrations. Now, for example, IV infiltrations that result in, say, compartment syndrome, would be a recognized adverse event. However, just a plain IV infiltration that doesn’t necessarily result in negative sequela would not be considered an adverse event. This is the type of unanticipated events that we are capturing. So, we actually started capturing data on IV infiltrations in our department, and in the last year we saw a huge rate of increase in IV infiltrations in a variety of our patients.

And we started looking into those patients to see what was the cause of IV infiltrations. Was it something related to pre-op nursing who. We’re traditionally placing these IVs, were these IVs coming from the floor? And so we did a little bit of analysis to try to reduce the number of IV infiltrations because it obviously results in unpleasant consequences for the patient.

Having to have another IV placed does delays in starting the OR case while the surgeon’s waiting for you to place another iv, potentially having to do an inhalation induction, which you may not have planned on. Et cetera. So we did some interventions, uh, and we actually were able to reduce the number of IV infiltrations.

But all of this got me interested in actually what do we do about the IV infiltrations themselves? Are we supposed to treat them for the majority of them? Do we just leave them alone? Do we compress them? And so this article is really interesting for me because one of the common medications that we do push is rocuronium.

And in large part, most of us were doing absolutely nothing. To manage these in IV filtrations, and so it was really interesting to me when I was doing research for this paper to learn about what is recommended management for these kinds of complications.

[Bechtel] This is a great lead in for when we start to discuss the management options for IV infiltration. I also asked Brook what’s next for her research and projects. Let’s take a listen to what she had to say.

[Brook]  So, I’m really interested in collecting data for me, if you do not know what the problems are, you can’t fix them. And so we are collecting vast amounts of data on unanticipated events, which is a type of, uh, anesthesia event that we have published on previously, and looking into what potential interventions we can do to further improve anesthesia care beyond the typical. Retrospective analysis of adverse events or near misses that we have traditionally been doing, and so my feeling is that this will move the needle on anesthesia care and help us improve patient safety going forward in the future.

[Bechtel] We are really excited to see where this project takes you and the impact on anesthesia patient safety.

We have more to talk about when it comes to IV infiltration of neuromuscular blocking drugs. Plus, we have more exclusive author content, but you will need to tune in next week for the exciting conclusion.

For a quick spoiler, we are going to review Figure 1 in the article which describes the authors’ proposed algorithm to manage this complication.

The first step is identification of paralytic infiltration. Followed by the immediate actions of:

• Attempt medication aspiration
• Place and utilize alternative IV access
• Demarcate infiltration site
• Document type, dose, and time of medication administered.

Next, treat the infiltration injury with considerations for the following:

• Apply nitroglycerin 2% paste
• Inject hyaluronidase through infiltrated IV and/or around the infiltration site
• Apply warm, dry compress and elevate the affected extremity.

Decrease the risk for recurarization with the following steps:

• Avoid or reduce the next dose of non-depolarizing neuromuscular blocking agent or use a depolarizing agent.
• Monitor intraoperative neuromuscular block depth with a quantitative monitor, if available
• The preferred reversal agent for rocuronium or vecuronium in this setting is sugammadex.

Finally, postoperative care involves monitoring extubated patients in the PACU for secondary recurarization for a minimum of 4 hours and serial exams on the infiltrated site.

Don’t worry we will go through the management in more detail next week, so mark your calendars!!

If you have any questions or comments from today’s show, please email us at [email protected]. Please keep in mind that the information in this show is provided for informational purposes only and does not constitute medical or legal advice. We hope that you will visit APSF.org for detailed information and check out the show notes for links to all the topics we discussed today.

Have you checked out the Look Alike Drug Vials Resource recently? This resource includes alerts and photos that show how look-alike drug vials and packaging can contribute to medication errors and impact patient safety. In May, there are examples of carboprost tromethamine injection stored in the spinal Marcaine compartment or ondansetron 4mg in 2ml next to Ephedrine 50mg/ml both with green caps stocked next to each other in the medication drawer, and more. We hope that you will check it out and consider contributing if you see look alike drug vials at your institution. There is more work to be done to keep patients safe from look-alike drug vials and medication errors.

Until next time, stay vigilant so that no one shall be harmed by anesthesia care.

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