System description
AWAC is comprised of a census view and a patient view with decision support alerts which are designed based on hospital protocols and current literature.
Data acquisition
Data are acquired from multiple sources in the EMR: laboratory, nursing flow sheet, physiologic network for live monitored data, device data (ventilator, mechanical circulatory support, ECMO & LVAD), patient demographics, patient diagnosis and co-morbidities by the International Classification of Disease 10th edition (ICD 10) codes, medications and patients care team contact information. The nursing flow sheet contains management data, some of which are displayed and also used in the calculations. For example, urine output is displayed, graphed and used in calculation of a rate in ml/kg/hr.
Similarly, documented chest tube output is displayed and also used for an alert when the rate exceeds a designated amount, eg greater than 300 ml in one hr. Finally, medication administration data can be used in alerting. When insulin is administrated a time is set for one hr to check for a glucose measurement. If not seen in the lab extract, an alert is sent to consider rechecking glucose. A complete list of alerts and limits are presented in Tables 1 (presented at the end of the paper) and 2 below.
Table 1 Icon definitions and the alerts associated with many of the icons Table 2 Color Codes for Alert Limits Alerts and icons
AWAC has a series of alerts and icons. The alerts range from simple high/low thresholds to more complex alerts involving calculations and several types of data extracted from the EMR. The alerts are also presented in a severity hierarchy following the International Organization for Standardization (ISO) recommendations for Health Informatics, Table 1 [11]. AWAC also has a series of icons representing important aspects of the patients care to enable easy identification on the Census View, described below. Examples icons are; a lung for mechanical ventilation, a pump for mechanical circulatory support (ECMO), a brain for ICP monitoring and so on. Icons are color coded based of severity. These alerts and icons are described in detail, Table 1.
Alerts
Certain alerts, typically called smart or intelligent alerts, have additional logic to help improve their relevancy and accuracy and to reduce alarm fatigue. If the field is empty, the alert activates with a simple threshold or limit. If the alert has additional parameters that influence when it activates, these will be described using the letters below:
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P = Alert is either disabled or different for pediatric patients. This does not include alerts that use weight, BMI, or height to scale for each patient.
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T = Alert uses trending, multiple values, medians, or averaging of values over time.
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F = Alert uses a formula or logic to calculate clinical parameters.
Priority
Based on ISO’s definition of the potential result of failure to respond, and the onset of harm, AlertWatch has defined the priority of the alerts. In particular, they have different Priority levels that distinguish the urgency of the alert, along with characteristics that that they recommend to ensure the user of the medical device correctly interprets and responds to the most urgent situations. There are, in order of lowest to highest priority:
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I = Information Signals
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L = Low Priority
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M = Medium Priority
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H = High Priority
Onset of harm
This ISO classification for onset of harm includes the following parameters. AlertWatch has added a None categorization for alerts that do not fall within the three ISO categories.
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I = Immediate. Having the potential for the event to develop within a period of time not usually sufficient for manual corrective action.
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P = Prompt. Having the potential for the event to develop within a period of time usually sufficient for manual corrective action.
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D – Delayed. Having the potential for the event to develop within an unspecified time greater than that given under “prompt”.
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N = None
Census view
Figure 1a is a census view of an ICU. Each rectangle represents a patient and has the bed number, the length of stay, the patient name, their age and the icons representing alerts and other important statuses of the patient, e.g. on a ventilator or dialysis; as described above, Table 1.
If the user is on the care team of any patients, the census can be limited to those patients with the My Patients filter. At the top of the census view there is a drop-down list which allows selection of different units within the hospital: ICUs, step-down units or floor beds, Fig. 1b. After a provider logs in for the first time and selects a unit, all subsequent log-ins by that provider will default to the units they last selected.
To the right of the unit selection is a set of drop-down Status Filters that defaults to My Patients as just noted. These are the patients in which the user is on the patients care team in the EHR. This drop-down can also select patients by different therapies e.g. receiving mechanical ventilation, on extracorporeal membrane oxygenation (ECMO), treated with nitric oxide, etc. Additionally, a variety of other patient censuses may be selected; Alert Level, Acuity Level, sequential organ failure assessment (SOFA) Score etc. [12]. Finally, to the right of that drop-down, there is an option to the View; Grid, List or Multi Patient view. This allows for different presentations or other ordering of the patients by activity of alerts, by the attending providing care or by the acuity of the patient, Fig. 1c. To the right of the grid is an alarm silence selection and a “?” which links to INSTRUCTIONS for use, standard COLOR LIMITS, ALERTS & ICONS definitions, PAGING and STANDARD and EMERGENCY references, Fig. 1c and Table 2.
At the far right are three dots “…” which allows switching to different AlertWatch applications, AWOR (operating room), AWOB (obstetrics), or AWPACU (Post Anesthesia Care Unit).
Each rectangle represents a patient as described in the legend above, Fig. 1. At the bottom of the census there is a brief description of each of the icons by name and a description of the color coding for different levels of care of the patient in the unit, Fig. 1a and 1c. These colors indicate, a newly admitted patient, ICU status patient, a moderate care or floor status. Each of the icons are listed in Table 1 and will be described in more detail below. Each one has color coding, which designates the acuity of each of these icons, see Table 1. Table 1 also provides a list of all the alerts. In general, green is normal range, yellow is slightly abnormal, and red is abnormal, Table 2. The alerts come in three levels; a black alert is information of interest and is represented by a black circle, a more concerning alert will be in red, the most concerning alert will be flashing red and can be associated with a text notification to a care provider via a mobile device, Table 1.
Patient view
Clicking upon a patient descriptor in the Census View opens a separate patient view in the same screen, Fig. 2a. The patient view has three panels. On the left is patient demographics and information, the middle section provides an icon view of the patient’s major organ systems with a beating heart and ventilating lungs. To the right is the Active Alerts Panel, which will list text descriptions of the active alerts for this patient. Alerts are color coded to prioritize severity: informational alerts are black text and represented by a black circle icon, for more important alerts the text is red (red alert icon), and the highest level of severity alerts are represented by a flashing circle icon and a scrolling red text alert and may be configured to activate a page to the appropriate care provider, as noted above. At the top left of the patient view there is a phone icon which provides contact information either by phone number or paging/text numbers for all the individuals on the patient’s care team, Fig. 2b. To the right of the phone icon is an envelope icon which allows users to directly contact the AlertWatch support team.
As noted in Fig. 2a, to the left-side of the Patient View screen shows the patients name, registration number, room location, age/gender, weight/BMI, Ideal Weight, and length of stay. The mid-portion shows the admitting diagnosis, below that ventilator days, urinary catheter days, central-line days, and acuity level; if an acuity level has been set by the care team. Below that are the sequential organ failure assessment (SOFA) and systemic inflammatory response syndrome (SIRS) scores, which are automatically calculated [12]. If these squares are tapped the window will provide the components of the scores and trends. For example, the SOFA table and trend plot is shown in Fig. 2c. Below the SIRS box is fluids inputs and outputs (I/O) balance. Hitting the I/O box will give a trend of the patient’s weight and the trend of I/O balance, Fig. 2d. The I/O balance is determined every hour and the cumulative plus or minus will be showed in the trend box. These data are extracted from the nursing flowsheet.
Below the I/O box is a display element containing isolation status. This signifies the level (if any) of isolation precautions required for this patient. If it is green there are none, if yellow there are standard isolation precautions, e.g. MRSA or C-difficile. If it is red, it signifies special precautions i.e. COVID-19. Selecting the isolation status icon it shows the specific infectious precaution. At the bottom, current infusion medications and allergies, Fig. 2e. As with all other icons and boxes when tapped, a pop-up window provides the specifics, e.g. allergies and infusion medications and doses of those medications.
The icon at the lower left provides a link to the live waveforms the patient’s physiologic monitors, if they are on the hospital network, Fig. 3. At the very bottom of the patient view is the color coding for the icon-based system. Gray meaning no data are available for that aspect of patient, green is normal range, yellow is marginal and, red signifies abnormal values, Table 2. An orange outline signifies a co-morbidity associated with that organ system or lab, “At Risk.” For example, if the patient has diabetes there will be an orange outline surrounding the glucose lab measurement, Fig. 2a. Clicking on a graphic with an orange outline will give more information on the specific co-morbidity.
The center section of the patient view provides an anatomically organized icon-based view of the patient’s major organ systems, below this are the current labs. If there are special monitors or devices those icons will be present, automatically added. For example, an intracranial pressure (ICP) column/monitor will appear to the left of the head icon if present, Fig. 4a. The brain color is gray if there are no information regarding level of consciousness, green if the level of consciousness is normal and yellow if there is an abnormal confusion assessment method (CAM) or Richmond agitation-sedation scale (RAS) score [13, 14]. In all cases when the icon or lab is tapped a pop-up window will open giving the trend values of that parameter. For example, Fig. 4b shows the trends of ICP and cerebral perfusion pressure (CPP) in this patient with an intracranial pressure monitor. Below the brain is an icon of the endotracheal tube (ETT). If the ETT is gray there are no data regarding risk factors or history for intubation. If the ETT is orange it notes there are risk factors for intubation from the most recent airway exam, green if there is a history of easy masking and intubation and red if there is a history of difficult intubation, e.g. requiring fiber optic or video laryngoscope, Figs. 2a, 5a and b. If there is an icon of a tube below the jaw coming out of the neck it means the patient has a tracheostomy or a stoma, (Fig. 7a discussed later). Below the neck is the trachea and main-stem bronchi and lungs. If there are co-morbidities with the lungs, such as asthma, there will be an orange outline of the trach and main-stem bronchi, Fig. 4a. Each lung has data regarding oxygenation, SpO2 and ventilation, end expired carbon dioxide (ETCO2). If the patient is being mechanically ventilated, a ventilator box will be to the right of the ETT, noting the mode of mechanical ventilation: respiratory rate (RR), peek inspiratory pressure (PIP), positive end expiratory pressure (PEEP), Driving Pressure (PIP-PEEP), tidal volume, Dynamic Compliance, FiO2, rapid shallow breathing index (RSBI) and arterial oxygen partial pressure to inspired fraction of oxygen ratio (P/F ratio), Fig. 2a [15,16,17]. If this ventilator box is tapped there are trends of these parameters. If the lungs are tapped a window will show trending of SpO2 and ETCO2 as well as recent blood gas measurements, Fig. 5c.
If the patient has a chest tube that icon will be in the lung on the left and the color of the chest tube will change as the chest tube output increases, Fig. 6a. When the chest tube is selected, the amount drained is shown as both increments and an hourly rate over time. If output exceeds more than 200 ml in one hour or 300 ml in 3 h, an alert is activated, Fig. 6b (these are configurable to site or patient specific needs).
Below the lung icon is the heart with aortic arch and inferior vena cava (IVC). The “fluid” level of the heart will be in the middle green, high yellow, high red or low yellow, low red depending on measurements of central venous pressure (CVP) or pulmonary artery diastolic pressure (PAD), if available and prioritized in a hierarchical manner. The green, yellow and red ranges of all values are in Table 2. If the heart has an orange outline it means their comorbidities, which can be determined by selecting the heart, will be presented along with blood pressure and CVP or PAP trends, Fig. 6c. If the patient has an implantable cardiac defibrillator (ICD) or a pacer these icons will attached to the Heart, Fig. 6a.
To the left of the heart is the liver, which will be green if liver function tests are normal and yellow if they are abnormal. As with all organ icons, if there is a disease such as cirrhosis of the liver, the organ will be outlined in orange. To the right of the heart is the current blood pressure and heart rate and if that box is tapped the trend of those values will be provided, Fig. 6c. The aortic arch will change colors from green to yellow to red depending on the blood pressure alert limits set by the system. On either side below the heart are the right and left kidneys. The kidney on the left-side provides an alert for chronic renal function as determined by the most recent creatinine value. If it is green the creatinine is normal, yellow if it is marginally high and red if the creatinine value is high, Table 2. Selecting the left kidney will provide trends of the creatinine as well as trends of blood urea nitrogen. The right kidney color designates the current values for urine output. Again, their range is a green, yellow and red depending on the limits set, Table 2. The urine output trend is provided by tapping that kidney, Fig. 6d. A curved arrow icon around a graphic representing the kidney represents a patient receiving continuous renal replacement therapy, Fig. 7a. A line through the kidney indicates a patient requiring hemodialysis, see icons and definitions, Table 1.
Below the icon to the human body are laboratory values for international normalized ratio (INR), lactate, platelets, hematocrit, hemoglobin, white blood count, potassium and glucose. As with all other values, tapping each column will provide a trend of those values and the colors of the column will depend on whether they are in normal, marginal or abnormal ranges.
On the right side of the patient view is the alert section where current active alerts will be presented either in black text, red text or scrolling red text depending on the urgency and importance of the alert. To the right of the alert section is a wrench icon which allows patient specific alerts to be configured.
Icons
A series of icons which are presented on the Census View and the Patient View that signify important aspects of patient status. These icons are defined at the bottom of the census view and in the online user guide and in Table 1. They are present on each patient square in the census view for the patients to which they apply.
Alerts icon
As stated above, the alerts icon are circles with a “!” in the middle. The alerts are either black, red or flashing red noting the degree of importance for that alert, Table 1. These alerts are configurable at the institutional installation. Some icons which are present on the census view are also presented in the upper left of the patient view because they do not relate to a specific organ; COVID-19 status (see below) and Patient Refuses Blood Products, Table 1.
Airway status
Again as noted above, the ETT icon can be presented in various colors; gray if there is no information, orange if there are risk factors for difficult intubation, green if there is a history of an easy masking and intubation and red if there is a history of a difficult intubation, Fig. 5a [18, 19].
COVID-19 icon
This icon presents in five levels/colors; gray represents no data available (as it does for all aspects of AW), yellow means the test is pending, red is COVID-19 positive, green is COVID-19 negative or Antibody positive and orange if the COVID negative test result is greater than 4 days old, indicating potential need for re-testing (this time window is configurable based on site policies/procedures), Tables 1, 2 and Figs. 5a, 6a.
Pump icon to signify mechanical circulatory support
The mechanical circulatory support (MCS) icon looks like a pump below the heart which can either be green for a left ventricular assist device (LVAD), orange for an intra-aortic balloon pump (IABP), and red for extracorporeal membrane oxygenator (ECMO), Fig. 7a. When these icons are tapped a window opens which provides specific data regarding that device. For example, Fig. 7b presents a patient with an LVAD device and the window presents flow, power, and RPM data as well as trends for that information. If the patient is on an ECMO device, the trend data will provide information regarding the flow, pressures, saturation, RPM and the sweeps speed. Trends are also provided for ECMO flow and resistance, as well as, venous and arterial oxygen saturation and oxygenator pressures, Fig. 7c.
Dialysis
The kidney dialysis icon is orange with a slash through it if the patient is in complete renal failure and on hemodialysis. If it is an orange kidney with an arrow the patient is on temporary support with continuous renal replacement therapy (CRRT) as described above, Fig. 7a.
Ventilator
The ventilator icon (lungs) is displayed on the census view when the patient is on a ventilator. The icon can be green, yellow or red depending on whether the ventilator pressures are in the normal, marginal or very abnormal range, e.g. high PIP or PEEP pressures as noted above, Figs. 2a, 7a. These alert color change limits are configurable. There is also a Ventilator Associated Event (VAE) alert, which will be discussed below in the Ventilator Management Tracking section. The VAE box is yellow if the FiO2 or PEEP have been increased to meet the criteria of a VAE; if these changes continue past midnight and red when midnight is passed [20, 21].
Nitric oxide
If the patient is receiving therapy with nitric oxide (NO) an icon is shown in the upper right and the nitric oxide dose in parts per million is presented in the ventilator box. There is also a red alert for nitric oxide, which provides the duration and dose in the Alert section.
SOFA
The SOFA score is in the left panel of the patient information button and also a red arrow icon. When the SOFA square is touched a box opens which provides the values which determine the SOFA score and also a trend, Fig. 2c. SIRS scores and trends are also displayed [12].
ICP monitor
The brain icon is presented when the patient has an inter-cerebral monitoring catheter. This can either be intracerebral or a lumbar catheter used in vascular procedures. If the icon is green it means the ICP is in the normal range, if it is red it is an abnormal range. When there is a catheter measuring cerebral fluid pressure a bar column is displayed to the left of the brain with the current ICP pressure. Tapping the icon provides trends of ICP and the cerebral perfusion pressure (CPP) data, Fig. 4a.
Other icons
There are other miscellaneous icons. There is an icon if the patient refuses blood products. If individual alert limits want to be changed for an individual patient, there is a wrench icon. If the wrench is purple it means a specific alert limit has been changed for this patient.
Ventilator management tracking; TV and VAE
The Center for Disease Control requires measurement of Ventilator Associated Events (VAEs) in patients receiving mechanical ventilation [21]. Occurrence of a VAE represents a deleterious change in oxygenation: either by FiO2 increased by 10% or greater or an increase in PEEP by 3 cm H2O or greater over a previously determined 48-h baseline value. These events are said to have occurred if these changes continued past midnight [21]. Given their role in quality measurement and assessment of health system practice, it is important that providers reassess the patient’s status to determine if these increases in ventilator support were truly required to maintain adequate oxygenation. For this reason, the VAE alert in AWAC is presented in two stages. When the triggered values are exceeded a yellow VAE alert is presented until midnight when the VAE now meets criteria for occurrence.
Sepsis alerts: the role of complex multiparameter decision support
Timely sepsis diagnosis and management is critical to the care of patients in the acute care setting. Early diagnosis and prompt initiation of antibiotics are proven to improve patient outcomes [22]. In 2018, the Surviving Sepsis Guidelines were updated to include a revised 1 h bundle of care which included measuring a lactate and re-measuring if initial was > 2 mmol/L, obtaining blood cultures prior to antibiotics, prompt administer broad spectrum antibiotics, and infusion of 30 ml/kg crystalloid for hypotension or lactate ≥ 4 mmol/L or initiation of vasopressors if hypotensive during or after fluid resuscitation [23]. Use of protocols to assist in early identification and treatment of sepsis have been shown to improve outcomes when utilized in the care of septic patients [24]. Decision support tools may have a role in identification and prompt management to improve patient care.
AWAC is designed to help providers both assess patients and provide alerts to remind them of various actions critical to the management of these patients and implement bundle-based recommendations. To facilitate adherence to the sepsis protocol, AWAC can alert/page the specific providers responsible for the various tasks: MDs for orders, RNs for blood draws and antibiotic administration and pharmacy for antibiotic preparation. If sepsis has been documented in the EHR, a black alert will appear or a red alert if septic shock is documented. Alerts for possible sepsis are based on the Third International Consensus Definitions for Sepsis and Septic Shock [25] and will appear if this diagnosis is present in the EHR or if the patient is ≥ 18 years old, qSOFA ≥ 2, SOFA score ≥ 2, and lactate is ≥ 2 mmol/L. If sepsis or septic shock is documented in the EHR, a window will be prompted with various actions that need to be performed within a given time window, Table 3.
Table 3 Organ Specific Sepsis Alerting This alert text will include everything that is due and when. If a test is completed beyond the end of the window, that segment of the alert will be removed. The logic behind the alerts is consistent with known sepsis diagnosis and treatment guidelines [24, 25]. For lactate, AWAC will use the last lactate value measured within 6 h prior to documented sepsis or the first measured in the hours following a sepsis diagnosis. If the lactate is < 2 mmol/L or there is none, then no alert for a second lactate is generated; however, if one is present and is ≥ 2 mmol/L, AWAC will search for a lactate value within 6 h of that value and if not present, alert that one needs to be evaluated.
Management of continuously monitored data: BP, SpO2, HR and RR
Patients in ICUs and step-down units are usually continuously monitored with networked physiologic monitors. Because of the need to address acute changes in these vital signs, alert limits are set to alarm when limits are breached. Unfortunately, artifacts occur, often due to motion, and resulting alarm frequency is so high alarm fatigue results [1,2,3]. To try to minimize the problem, AWAC employs scrolling median values to trigger alerts. The median values of each variable is determined over a 5-min period which is updated every one minute. The scrolling median time period is configurable. This method will remove short term “outlier/artifact” values reducing these measurements producing an alarm, but will delay the alert by a few minutes depending on the scrolling period selected.
Mobile use
AWAC has been configured and tested for use with mobile devices; tablets and smart phones. An application is available in the Apple App store by searching “Alertwatch Inc.” VPN access is required for out of hospital use. It opens to the census view and when a patient is selected, it is designed to swipe to view all the sections: patient view, patient information and alerts, provider contact and waveforms. The provider can be called directly if their phone numbers are in the EHR.