Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes...
-
Upload
andrew-hutchinson -
Category
Documents
-
view
214 -
download
0
Transcript of Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes...
![Page 1: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/1.jpg)
Event Communications
Overview of Concepts
![Page 2: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/2.jpg)
Event communications – infusion pumps
• Distinguishes non-alarm events – operational milestones and key parameter changes
• Vs. Alarms – “intended to engage immediate response from the clinician”. These are handled by ACM Profile.
![Page 3: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/3.jpg)
Event communications – infusion pumps
• Document gives detailed use cases and message examples
• Proposes new PCD event message, PCD-10
• To enable receiving systems such as CDSS and clinical workflow applications to more easily separate event information from the overall data stream.
![Page 4: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/4.jpg)
Event communications – infusion pumps
• Challenge – pumps usually not “aware” of how they are being used clinically
• Numerous distinct use cases and variations
![Page 5: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/5.jpg)
OBX-13 User defined access checks
• Definition: This field permits the producer to record results-dependent codes for classifying the observation at the receiving system.
• Ex. Filtering out microbial sensitivities so that ordinary users don’t see results with exotic expensive antibiotics.
• Data type ST string, not repeatable
![Page 6: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/6.jpg)
OBX-13 User defined access checks
• That is, this is somewhat of a grungy wastebasket category.
• That said, where HL7 V2 gives you a hook, however grungy, we tend to need to use it… Ex. Our “enriched” set of OBX-8 Abnormal flags
![Page 7: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/7.jpg)
Generalizing to events in the non-pump world
• The pump discussion gives patterns for much of the non-pump world
• But let us now do some free association about what other things events may be as well
• This will ideally be a Group rumination, not a presentation. I’ll make at least some assertions you ought to disagree with and want to discuss (not everything I’ll assert I agree with myself…)
![Page 8: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/8.jpg)
Unifying principle 1• Let’s not alienate event communication from
observation reporting: it is observation reporting, though of a particular kind
• That applies to alarms as well: they are another particular kind of observation reporting
• If we keep the communication unified, it simplifies comprehension, and perhaps implementation as well
![Page 9: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/9.jpg)
Another unification• Another kind of observation reporting we
already have treated to some degree is aperiodic or episodic observation reporting
• Periodic observation reports are triggered on the clock tick – aperiodics, like events, are triggered by something else
![Page 10: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/10.jpg)
Aperiodics triggered on “something else”
For example:
• pushing the start button on a cuff pressure
• completion of a one-shot thermodilution cardiac output estimation procedure
• beat-to-beat or breath-to-breath measurements
• …
![Page 11: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/11.jpg)
Q. What is different about events vs. other observation
reports?
Possible partial answer: it’s in the (multifarious) ways we process them:
• Time-critical response often (not always) involved
• They are a different kind of algorithm input in being discrete, and tightly time-located
![Page 12: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/12.jpg)
Event processing generalities and abstractions
• Event operational definitions –
• Event Processing Technical Society – event: anything that happens, or is contemplated to happen
• Event object an object that represents, encodes, or records an event, generally for the purpose of computer processing
![Page 13: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/13.jpg)
Events can be raw or processed
• Raw event – records a real-world event
• Derived event – “event generated as a result of applying a method or process to one or more other events” (EPTS)
• Complex event – “abstraction of other events, called its members
![Page 14: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/14.jpg)
Composite event
• “derived complex event that is created by combining events using a specific set of event constructors such as conjunction, disjunction, and sequence” (e.g. HR < threshold and SpO2 < threshold)
![Page 15: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/15.jpg)
Event patterns
• E.g. descending or ascending pattern of values, specific sequences of events
• Often used to determine when to apply a business rule
![Page 16: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/16.jpg)
Window
• Bounded portion of an event stream
![Page 17: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/17.jpg)
Instantaneous event
• Operational definition: “An event whose duration is less than the granularity of any clock that is applied in the system” (EPTS)
• Some events are a priori instantaneous – from their logical definition they plain don’t have a duration (e.g. threshold crossing)
![Page 18: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/18.jpg)
Events have attributes
• Timestamps, often more than one, measured against more than one clock (more later)
• Event source
• Event type
• Location (if significant)
• Associated data (e.g. may link to a measurement vector in a pump scenario)
![Page 19: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/19.jpg)
Event types
• Change of state, physiological or technical
• Threshold crossing (as in a measurement crossing an alarm limit)
![Page 20: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/20.jpg)
Event objects propagate in networks
• Event producer
• Event consumer
• Event pathway
• Collection of event pathways can constitute a complex network, with complex additional processing at nodes – e.g. in clinical decision support systems
![Page 21: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/21.jpg)
Clock (EPTS)
• A process that creates an ordered ascending sequence of type Time with a uniform interval between them. Each value is produced at a tick (or clock tick).
• There may be many clocks in a system. This leads to a large class of challenges in clock error propagation and clock error mitigation (cf. NTP algorithms)
![Page 22: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/22.jpg)
Clock granularity
• The length of the interval between clock ticks is termed “granularity” by the EPTS.
• In our world of periodic sampling, we might think of it as a sampling interval (or reciprocal sampling frequency).
![Page 23: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/23.jpg)
Latency
• Very generally, a time delay
• Many kinds, depending on context
• An important one for us is latency as time delay between an event’s actual occurrence and its (first) detection in the system
![Page 24: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/24.jpg)
Jitter
• Also many kinds depending on context
• Ex. Variable deviation between intended time and actual time of measurement, as in clock tick jitter
• Typical measures statistical, e.g. median absolute deviation or root mean square deviation (a/k/a standard deviation))
![Page 25: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/25.jpg)
Jitter, contd.
• Often the absolute latency is less of a concern if it is consistent (lacks substantial jitter)
![Page 26: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/26.jpg)
HL7 an event-driven communications specification
• “The Standard is written from the assumption that an event in the real world of healthcare creates the need for data to flow among systems. The real-world event is called the trigger event.” (HL7 Ch 2)
![Page 27: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/27.jpg)
HL7 an event-driven communications specification 2
• “For example, the trigger event a patient is admitted may cause the need for data about that patient to be sent to a number of other systems.” (HL7 Ch. 2)
• (event producer to multiple event consumers)
![Page 28: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/28.jpg)
HL7 an event-driven communications specification 3
• “The trigger event, an observation (e.g., a CBC result) for a patient is available, may cause the need for that observation to be sent to a number of other systems.” (HL7 Ch. 2)
• (i.e. event producer to multiple event consumers)
![Page 29: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/29.jpg)
HL7 an event-driven communications specification 4
• “When the transfer of information is initiated by the application system that deals with the triggering event, the transaction is termed an unsolicited update” (HL7 Ch. 2)
![Page 30: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/30.jpg)
UML Timing diagrams sd UMLTiming Diagrams
Tim
eL
ine
1
inactiv e
> threshold
activ e
< threshold & !latched
inactiv e
Tim
eL
ine
2
operational
initializing
idleState lifeline
value lifeline
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95100
Tim
eL
ine
1
inactiv e
> threshold
activ e
< threshold & !latched
inactiv e
Tim
eL
ine
2
operational
initializing
idleState lifeline
value lifeline
![Page 31: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/31.jpg)
ACM alarm (event) attributes sometimes relevant
• Not always
![Page 32: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/32.jpg)
ACM alarm (event) identity - relevant
class Alarm Content
Ev entCodeIEEE
notesCode from MDC Nomenclature Event partition. Usually requires alarm source (a metric or a device) to disambiguate. Least significant bit indicates whether source is metric or device.
«enumeration»Ev entSourceIEEE
notesCode from MDC Nomenclature SCADA partition indicating for a limit alarm what parameter is out of l imits, or for a technical alarm, a code from the object partition indicating the source of the technical alarm
Alarm identity
![Page 33: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/33.jpg)
Alarm State class Alarm Content
«enumeration»AlarmState
inactive active latched
notesSent as OBX-5 Observation Value of a child OBX segment of the alarm bundle
«enumeration»AlarmInactiv ationStateIEEE
enabled audio-paused audio-off alarm-paused alarm-off
notesPertains to a set of device alarms - individual, group, system
Sent as OBX-5 Observation Value of a child OBX segment of the alarm bundle
Alarm state
«enumeration»Ev entCurrentPhase
tpoint start continue end update escalate de-escalate reset
notesSent as OBX-5 Observation Value of a child OBX segment of the alarm bundle
![Page 34: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/34.jpg)
ACM Alarm Limits
class Alarm Content
NumericAlarmRange
- low-limit: float- high-limit: float
![Page 35: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/35.jpg)
Latching sd Latching
Tim
eL
ine
1
inactiv e
> threshold
activ e
< threshold & !latched
inactiv e
Tim
eL
ine
3
inactiv e
> threshold
activ e
latch released
inactiv e
If value goes back below threshold here on a latched alarm, the alarm stays active until the latch is released (by operator pressing "silence") -- you don't want to miss an important, but short duration, alarm
if alarm is not latched, it goes inactive as soon as the value goes back below threshold
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95100
Tim
eL
ine
1
inactiv e
> threshold
activ e
< threshold & !latched
inactiv e
Tim
eL
ine
3
inactiv e
> threshold
activ e
latch released
inactiv e
If value goes back below threshold here on a latched alarm, the alarm stays active until the latch is released (by operator pressing "silence") -- you don't want to miss an important, but short duration, alarm
if alarm is not latched, it goes inactive as soon as the value goes back below threshold
![Page 36: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/36.jpg)
ACM Alarm priority encodings
class Alarm Content
«enumeration»AlarmType
phys tech
notesDerived from nature of EventSourceIEEE, which is represented in low-order bit of EventCodeIEEE
Maps to following OBX-8 Abnormal flags values:
SP - Alarm source physiological ST - Alarm source technical
«enumeration»AlarmPriorityIEC
no-alarm LOW_PRIORITY MEDIUM_PRIORITY HIGH_PRIORITY
notesMaps to following OBX-8 Abnormal Flags:
Priorityno-alert - PNLow - PLMedium - PMHigh - PH
AlarmPriorityIEEE
«enum»+ no-alarm = 0+ low-pri-t-al = 1+ med-pri-t-al = 2+ hi-pri-t-al = 4+ low-pri-p-al = 256+ med-pri-p-al = 512+ hi-pri-p-al = 1024
notesMaps to AlarmPriorityCen and AlarmTypeCen
![Page 37: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/37.jpg)
HL7 V2 Representation issues class HL7Representation
ChildOBXContent
- sub-id: Sub-ID- observationIdentifier: int- observationValue: int
notesTypical pattern:OBX-3 contains code identifying the individual attributeOBX-5 contains value
OBRContent
notesAll attributes of a particular alarm instance are constrained to be "belong to" an OBR, so as to bind together all the aspects of the alam
Sub-ID
- mds: int- vmd: int- chan: int- parametric-instance: int- child-instance: ChildOBXAttributeIdentifier
notesDistinguishes:
-specific source within MDC containment tree-specific attribute of the alarm - attribute identified by child-instance
AlarmHL7Representation
- obr- obx
MetricSpecificOBXSegment
notesOBX-3 Observation Identifier contains MDC nomenclature identifier for out-of-l imit metric
OBX-5 Observation Value contains current (out-of-l imit)numeric value
OBX-7 Reference Range contains alarm limits set on the device
OBX-8 Abnormal Flags contains severity and whether alarm source physiological or technical
OBX-14 Date/Time of observation
«enumeration»ChildOBXAttributeIdentifier
EventSourceIEEE AlarmPhase AlarmPriorityIEC AlarmState AlarmTypeIEC
notesFixed values for attributes:
Dev iceSpecificOBXSegment
notesOBX-3 Observation Identifier contains MDC nomenclature object identifier for technical alarmsource
Ev entMainOBXSegment
notesOBX-3 Observation Identifier
OBX-5 Observation Value contains current (out-of-l imit)numeric value
OBX-14 Date/Time of observation (start)
AlarmAttributeCarrierOBXSegment
notesCarries a general attribute of the alarm, distinguised by ChildOBXAttributeIdentifier part of sub-ID
![Page 38: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/38.jpg)
What else do we want to be able to communicate about
events?• They can be created by non-device
information systems – this is an important function of clinical decision support systems
![Page 39: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/39.jpg)
What else do we want to be able to communicate about
events?
• They need to be composable – a raw event may need to convey supporting data, a derived alarm may need to carry the events it is built on, and their supporting data…
![Page 40: Event Communications Overview of Concepts. Event communications – infusion pumps Distinguishes non-alarm events – operational milestones and key parameter.](https://reader035.fdocuments.in/reader035/viewer/2022062618/551491ea550346d36e8b5298/html5/thumbnails/40.jpg)
• ???
• Your turn…
What else do we want to be able to communicate about
events?