Episode #8 Introducing Rapid Response to Questions from our Readers

Hello and welcome back to the Anesthesia Patient Safety Podcast.  My name is Alli Bechtel and I am your host. Thank you for joining me for another show.

Today, we’re going to explore another area of the APSF website. If you haven’t found the section called “Rapid Response to questions from readers,” I’m going to give you a moment to grab a cup of coffee and head over there as we continue our journey towards improved patient safety.  You can find this section from the top menu of the APSF homepage, under Newsletter and click on the third one down.  You can also check out the links that I included in the show notes.

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

This important patient safety resource, Rapid Response to questions from readers, was originally called Dears SIRS and SIRS stands for Safety Information Response System.  This is a regular column in our newsletter and has a home on our website as well.  The purpose of this resource is to enable relatively quick communication of technology-related safety concerns from anesthesia professionals using the technology for patient care with input and responses from manufacturers and industry representatives.  The goal is to unite clinicians and industry representatives to talk about safety challenges and to bring about changes when needed to improve patient safety.

Okay, now we are going to look at a Rapid Response that appeared in our June 2019 Newsletter and was submitted by Sheron McLean, a clinical assistant professor in the Department of Anesthesiology at Michigan Medicine in Ann Arbor, Michigan.  I will include the link in the show notes and you can find it from the Rapid Response to questions from our readers section on the APSF webpage and scrolling down on page 2.

I am going to read the letter first.  McLean writes,  “Dear Rapid Response, The ASA standards for basic anesthetic monitoring require that all patients receiving an anesthetic have arterial blood pressure monitored, at a minimum frequency of once every five minutes, except under extenuating circumstances.¹ Monitoring gaps may occur for various reasons including patient positioning or pausing the automatic cycle for placement of an arterial line. When this occurs, the anesthesia professional sometimes fails to re-engage the monitor to return to periodic measurements, which can lead to extended monitoring gaps. In addition to this human issue, there is a system issue. The design features of some patient monitors, including the General Electric (GE) CARESCAPE B-850, which we use in many of our operating rooms at Michigan Medicine, will display the last measured blood pressure without providing an audible or visual alert if this measurement is not current. This may lead to a false impression that blood pressure is being measured, when in fact the blood pressure displayed is an older measurement. This is in contrast to a detached ECG cable or temperature cable that results in audible alarms. Additionally, a poorly attached cuff or faulty cuff may continue to cycle in an attempt to attain a blood pressure reading without an alert. This can lead to monitoring gaps and potentially compromise patient safety. At Michigan Medicine, we have a system that is designed to integrate with patient monitoring devices and provide alerts for actual and potential issues. This system will alert a provider to a monitoring gap; however, the application needs to be open and running in the operating room and will provide a single beep to alert the anesthesia professional at the six-minute mark if a blood pressure reading is not obtained. It seems as though there should be a simple software solution to this monitoring issue on the GE models that would provide for an alert when a new blood pressure reading is not obtained shortly after five minutes. While this will certainly not eliminate the problem of monitoring gaps, it may help to better identify an issue that can easily be remedied.”

Now, have you ever experienced a non-invasive monitoring gap while providing anesthesia patient care? McLean asks a great question.  Let’s talk about the reply from Cory Stahl, the global marketing manager for GE Healthcare’s patient monitoring business. Stahl points out that this is a challenge for obtaining the non-invasive blood pressure measurement and the appropriate display of the blood pressure on the monitor in the OR. GE has a history of designing patient monitors with support from the most up-to-date industry standards for delivering patient care as well as patient and clinician feedback on the user interface and reliability of the monitor.  McLean specifically writes about the Carescape B850 Monitor that is designed to be used in multiple care areas and for a variety of cases, thus this monitor was designed to be flexible with different options to configure the monitor depending on the patient, the patient care area, and the case. Looking at just the non-invasive blood pressure display option reveals some of this flexibility since it can be configured for specific patients. Stahl provides the example of a patients in the neonatal intensive care unit who may require less frequent blood pressure measurements and for these patients, the monitor can be set to display the last blood pressure measurement for up to 4 hours with a greyed-out display after the first 60 minutes. For patients in the operating room who need more frequent blood pressure measurements, the monitor can be set to automatically cycle every 5 minutes and the last measured blood pressure will no longer be seen on the display after 5 minutes.  Check out the APSF website for pictures of what these examples look like on the Carescape B850 monitor.  Stahl also provides information about configuring the monitor for automatic blood pressure cycling at minute intervals of 1, 2, 2.5, 3, 4, 5, 10, 15, 20, and 30 minutes as well as hour intervals of 1, 2, or 4 hours.  You will need to set the cycle time a well as turn on the automatic cycling function by selecting the “start cycling” option. Another feature of this monitor is that you can change the monitor defaults under the Care Unit Settings and the parameters section by selecting the non-invasive blood pressure display timeout duration. If you select the duration of 5 minutes, the last BP measurement will be removed from the display and replaced with dashed lines 5 minutes after the last measured blood pressure is obtained. The other options are for longer display timeout including 30 minutes until greyed-out numbers with 1 hour total display time for the last measurement or 60 minutes until greyed-out numbers with 4 hours total display time for the last measurement as in the example of the patient in the neonatal ICU that I already talked about.

There is another feature of the monitor to help clinicians see when the last blood pressure measurement was performed.  This is the Non-Invasive blood pressure cycle time display that can be configured for numerical display under monitor set-up in the care unit settings and parameters.  This function displays the specific time of the last blood pressure measurement in the parameter window on the bottom right. You will be able to see the timestamp for manual and automatic BP measurements. When you are using the non-invasive BP auto cycle function, you will also be able to see a countdown until the next scheduled BP measurement.

Let’s take a closer look at the non-invasive BP parameter window on the monitor. This is probably something that you have spent quite a bit of time looking while providing safe anesthesia patient care. When the monitor starts trying to take a BP measurement, you will see the cuff pressure on the right side of the parameter window as a visual indicator of the blood pressure measurement attempt.  After the cuff pressures read 0 on the display and the systolic and diastolic values are not visualized, this means that the BP was not able to be obtained successfully. The NIBP Auto Mode will automatically cycle again to try to take another BP measurement at the next set measurement interval. If the measurement is unable to be obtained at the next set measurement time, then the automatic mode will be deactivated and the display will show dashed lines instead of numbers. If there is a technical reason for the failed measurement, the monitor will display an error message, such as loose cuff, as well as an audible alarm to help troubleshoot the non-invasive BP monitoring. In addition, you may want to take a look at the Carescape monitor’s operator’s manual or contact GE Healthcare for additional information on the available setting configurations for blood pressure measurements.

Thank you, McLean and Stahl, for getting the conversation started on this important topic.  Let’s keep it going by taking a look at the editorial commentary by Jeffrey Feldman, the chair of the APSF committee on technology about the challenges of designing monitoring displays and alerts.  I will link to the article in the show notes and I hope that you will click over to our June 2019 Newsletter as well by going to the top menu of the APSF homepage, under Newsletter, fourth one down is the Newsletter archives, and then scroll down until you get to 2019 and click on “June 2019.” You will find the article on the left after scrolling down, under the Rapid Response heading.

This is such an important topic since the ASA Standards for Basic Anesthetic Monitoring states that “every patient receiving anesthesia shall have arterial blood pressure and heart rate determined and evaluated at least every 5 minutes” with an asterisk that offers the option to change this interval at the discretion of the anesthesia professional with appropriate documentation of this change in the anesthesia record. Our monitors have options for automatic cycling at set intervals depending on the patient and the case, but at times this automatic cycle may be stopped due to positioning or arterial line placement or may fail to capture a new blood pressure measurement. This is quite the engineering challenge to design a monitor given the variety of conditions during patient care. There are some great configuration options from GE to help address these issues in their monitor.

Let’s look at some of the challenge that Feldman addresses.  First, how long to display the blood pressure measurement.  The clinician may not see the BP measurement immediately so it will need to remain on the display for a certain length of time and this brings up some questions.  Should the measurement be removed after the set auto cycle interval? How long should the monitor display a single manual measurement? How long is the blood pressure measurement useful for revealing information about the patient’s physiology? It is important the clinicians pay attention to audible alerts or changes in the display so that they can rapidly recognize blood pressure monitoring gaps of greater than 5 minutes. This is definitely not a rare event when we are concentrating on patient care and then look up and see that more than 5 minutes has passed since the last blood pressure measurement.

The next challenge that Feldman points out is the optimal alert for a blood pressure monitoring gap.  It may not be as simple as an audible alert every time the non-invasive BP fails to take a measurement since some of these alarms will become additional nuisance alarms during intentional cuff disconnects due to patient and cuff positionings.  Additional questions about this alert include what is the optimal alert? Is this the time for a gentle audible alert or a loud alert? What is the optimal monitor display to make sure that the clinician recognizes the lapse? What information should be displayed to help the clinician solve the problem of the failed BP measurement? The reason this is a challenge is because there is a potential to increase the rate of nuisance alarms in the OR and add to alarm fatigue without actually solving the problem of BP monitoring gaps.

One solution to these challenges was described by McLean in the original letter and included an independent system that interfaces with the clinical application and the monitoring standard to then alert the clinician user when there is a monitoring lapse.  This option may be a complex solution and depends on the patient monitors, but with the electronic medical records used in the clinical environment today, this is definitely a consideration and similar alerts have been implemented for bedside monitoring.  Even with this kind of alert, what is the best way to alert the clinician? Visual only? Visual and audible? How big should the notice be? Can it temporarily hide the patient record? How loud should the audible alert be? This solution does not provide a coordinated effort between the patient monitor and the electronic medical record.

Is there another option? Julian Goldman and colleagues describe another option in the Medical Device “Plug-and-Play” Interoperability Program that includes an Integrated Clinical Environment where devices are able to communicate with one another. This is such a cool idea.  Just imagine…you start your anesthesia record and then all the medical devices connected to the patient are aware of the context of care. In the integrated clinical environment, engineers can coordinate the functions of medical devices with appropriate alerts depending on the standards and care protocols with the benefit of decreased false alarms.  This integrated environment would free the anesthesia provider to provide safer care without needing to manage and understand multiple devices and display options from different manufacturers. Accurate and timely blood pressure measurements are necessary for safe anesthesia care and we have come a long way from manual BP measurements. The automatic devices are definitely an upgrade and with these monitors, we are able to obtain more frequent blood pressure measurement. Many of the monitors we have today allow us to closely monitor patients and provide safe care. Going forward, we can work towards improved patient safety with patient and clinician centered monitoring designs.

Thank you so much for joining us today for our discussion on monitoring gaps as we continue our journey towards improved patient safety. If you have any questions or comments from today’s show, please email us at [email protected].

Visit APSF.org for detailed information and check out the show notes for links to all the topics we discussed today.

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

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