Episode #122 Hyperinflation System Use and Best Anesthetic Practice During Endoscopy Procedures

Hello and welcome back to the Anesthesia Patient Safety Podcast.  My name is Alli Bechtel, and I am your host. The October 2022 APSF Newsletter is here. There are so many great articles that we will be covering right here on the podcast. I hope that you are as excited as we are!!

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

We are diving into the October 2022 APSF Newsletter today and we are getting started with a Rapid Response to Questions from our Readers section. This section represents an important way to work towards keeping patients safe during anesthesia care since it allows quick communication of crucial technology-related safety concerns submitted by our readers with follow-up and response from manufacturers and industry representatives. We use a lot of technology when providing anesthesia care. If you have a technology-related safety concern, consider submitting it to the APSF Newsletter. I will include a link to the Guide for Authors, the word count is less than 1000 words with no more than 15 references. The deadline is November 10^th for the February Newsletter, so what are you waiting for?!

Our featured article today is “Transportation of Pediatric Patients With Hyperinflation System” by James Xie and colleagues. To follow along with us, head over to APSF.org. Click on the Newsletter heading, first one down is the Current Issue. Then, scroll down until you get to the Rapid Response Section and our featured article. I will include a link in the show notes as well.

The authors write, Dear Rapid Response so, here we go. One of the highest risk activities during anesthesia care is patient transport. Up to 5% of pediatric anesthesia adverse events occur during patient transport especially respiratory and airway complications. Transport equipment can help to keep patients safe during transport. Human factor engineering is so important for designing medical devices that are used by anesthesia professionals during transport by taking into consideration the capabilities and limitations of the healthcare professionals using the equipment and designing equipment that is safe, reliable, and efficient in various situations. The authors use a human factors perspective to discuss the design of a pressure valve on the SunMed Ventlab HS4000 Series Hyperinflations System. Take a look at Figure 1 and Figure 2 in the article. Figure 1 provides several views of the Hyperinflation system. If you look closely at the Adjustable Pressure Valve, you can see that the clockwise arrow is labeled “Open.” There are two concerns here. The white text on the white plastic is hard to read and usually clockwise rotation leads to closure of a valve. The authors started using this product instead of the Jackson-Rees transport circuits as a result of a supply shortage at their institution.

Let’s look a little closer at the SunMed Ventlab Hyperinflation System. This includes a color-coded pressure manometer and an adjustable pressure valve that is a “stay-put dial” that can be used to set a static pressure, but remember the valve must be turned clockwise to open the valve and counter-clockwise to increase the pressure. This design is opposite of many other hyperinflation systems. Have you heard the phrase, “righty-tight, lefty loosey? This is easy to remember for turning right or clockwise to tighten the valve and increase pressure and left or counterclockwise to loosen the valve. But that will not work with this device. Another consideration with this device is the white plastic dial that includes a white label indicating the direction of the turn to open the valve. For anesthesia professionals who were used to the other device, the changes on this device and the unclear labeling were confusing especially during patient transport. This is a big threat to patient safety if positive pressure ventilation is needed. Once the design differences were discovered, education was provided to the department to ensure safe use of the newer hyperinflation system.

The authors continue the article with additional information about the pressure dial on the hyperinflation system and the adjustable pressure-limiting valve on the anesthesia machine. Have you used the adjustable pressure-limiting valve on an anesthesia machine today? Did you know that the International Organization for Standardization has standards that apply to the design of all APL valves on anesthesia machines? Let’s look at regulatory standard ISO 80601-2-13:2011 which states that exhaust valves, including APL valves,  should have their pressure adjusted such that clockwise rotation closes the valve thus increasing circuit pressure and counter-clockwise rotation opens the valve leading to decreased pressure in the circuit. Thus, the regulatory standard applies to the “righty-tighty, left-loosey” principle. The APL valve is one of the most commonly used devices while providing anesthesia care, so anesthesia professionals are used to turning a valve right to increase the pressure in order to provide positive pressure ventilation. This is an important patient safety consideration especially since supply shortages are ongoing and we need to be prepared for devices substitutions going forward. One way to make sure that substituted devices are used correctly and safely is for supply chain managers and clinicians to work together to address design differences and to provide education about the differences and patient safety implications. At the authors’ institution, the SunMed Ventlab Hyperinflation system contained a dial design that was opposite of the standard Mapleson circuits that the anesthesia professionals were used to using. Thus, education about this design difference is imperative to ensure correct use which may include appropriate in-service education before anesthesia professionals must use the unfamiliar substituted device during patient care.

Thank you so much to Xie and colleagues for submitting this rapid response article. I will give you a moment to freshen up your cup of coffee before we hear the response from SunMed.

We are back already because remember, it is a rapid response. Gary Banks and Jessica Hoke provide the response from SunMed about their VenlabHS4000 series hyperinflation system with integrated manometer and pop-off. This device is one of the most widely used hyperinflation systems in the market. Do you use this at your institution?

SunMed acknowledges that education is the first step before healthcare professionals use a new-to-them product in order to learn about the device and highlight any different features keeping in mind that different performance features may not mean counterintuitive. SunMed provides the following education materials including: comprehensive instructions for use, training and education, and in-service support across our breadth of products. I will include the links to the education materials in the show notes as well which is a great resource to check out before using this device for patient care.

The education reviews using and interpreting the pressure relief valve. Keep in mind that this valve does not contain an adjustable pressure-limiting valve and is not designed to function in the same way. The Ventlab hyperinflation system contains a pressure relief valve that rotates forward to close the valve and restrict flow, thus increasing the pressure and rotates backwards to open the valve, thus decreasing the pressure. This lab was developed by a clinician taking into consideration human factors and ease of use since the valve can be adjusted with one hand by the thumb during use while being able to continuously monitor the pressure on the integrated manometer while also monitoring the patient. There is also a visual aid on the valve which can help to identify the position of the valve since full red means the valve is completely closed and no red means that the valve is completely open. This indicator window can be reviewed before using the hyperinflation system as well as during use.

Check out figure 1 in the response which shows the Ventlab hyperinflation system device with the pressure relief valve and what it looks like when the valve is closed and open. Thank you to SunMed for reviewing the use and design features of this device and responding to the authors. There is a call to action for the importance of proper education before a new device is introduced into clinical practice and this is especially important in the face of supply shortages and device substitutions on short notice.

Let’s turn the page on the October 2022 APSF Newsletter and discuss another article. Our next featured article is “Evolving Standards for Anesthesia During Advanced GI Endoscopic Procedures” by Richard Prielipp and Stuart Amateau. This article is a reprint from Anesthesia and Analgesia June 2022 with permission from the International Anesthesia Research Society. This is an important article since endoscopic procedures are common in the United States with over 11 million colonoscopies, 6 million upper gastrointestinal endoscopic procedures, 180,000 upper endoscopic ultrasound examinations, and about 500,000 ERCP procedures each year. Anesthesia care may be required for certain procedures and for patients with multiple medical comorbidities, advanced frailty, and decreased physiologic reserves. When was the last time that you provided anesthesia care for an endoscopy procedure and what is your choice for the “best anesthetic” for these procedures? The authors report that variability in anesthetic care for these procedures may be due to lack of validated outcome data and an undefined standard of care combined with patient comorbidities, inconsistent practioner skills, changing procedural needs, inconsistent resources, and inconsistent facilities for these procedures. It is vital that anesthesia professionals working in this space understand the unique challenges and requirements of the GI proceduralist in order to provide safe and efficient anesthesia care. So, what are the models for sedation and anesthesia care? There is moderate sedation that is endoscopist-directed sedation which was the standard in the 1990s. Over the past 20 years, there has been a shift to increased use of anesthesia professional led care for sedation or general anesthesia. The benefits of deep sedation provided by an anesthesia professional includes maintaining patient safety, decreased failed interventions, improved patient satisfaction, and improved recovery from sedation. For long and complex procedures, general anesthesia may be required to secure the airway and provide a stable, motionless field.

For most endoscopic procedures, the options for anesthesia care range from minimal or no sedation for simple procedures in motivated patients to deep sedation with general anesthesia reserved for select patients and procedures. Here are some considerations when deciding between deep sedation or determining if a patient requires general anesthesia:

Early pre-procedure communication between the endoscopist and the anesthesia professional.

Patient positioning during the procedure since prone position or lateral position promotes flow of any gastric contents out of the mouth rather than into the trachea in a supine patient.

Patients at risk of aspiration or loss of airway during the procedure under deep sedation may require either general anesthesia or less sedation.

Keep in mind that general anesthesia involves greater expense, time, resources, hemodynamic changes, and oral or dental trauma.

Now, that we have made it to the end of the article have we settled on the best anesthetic for upper GI endoscopy and ERCP procedures? What do you do in your practice? We can really see some pros and cons to each technique. Hmmm…. looks like we will need to review the article, “Pro-Con Debate: Monitored Anesthesia Care Versus General Endotracheal Anesthesia for Endoscopic Retrograde Cholangiopancreatography” by Luke Janik and colleagues from the October 2022 APSF Newsletter. Don’t worry, we will cover it on a future show, right here on this podcast, so stay tuned. This discussion is so important for keep patients safe and optimizing anesthesia care during endoscopy procedures.

That’s all the time we have for today. 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.

The October 2022 APSF Newsletter is finally here! We are so excited to feature many of these great articles on our upcoming shows. So, mark your calendars. In the meantime, you can head over to APSF.org and click on the Newsletter heading. First one down is the current issue. Go ahead and check it out!!

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

© 2022, The Anesthesia Patient Safety Foundation