Applying HL7 in the Acute Hospital setting

1. Applying HL7 in the Acute Hospital setting Philip Firth IM&T Strategy Implementation ManagerWrightington, Wigan & Leigh NHS Trust Philip.Firth@wwl.nhs.uk

2. Introduction • Look at some of the integration issues that Acute Hospital NHS Trusts typically need to address • Look at an example project with complex interface needs – accident & emergency • Look at requirements for linking Acute Hospital NHS Trust systems to LSP solutions and the Spine

3. Acute Systems IntegrationTypical Issues

4. Issues … • Standards - what standards??? • Implementation issues – PAS, Pathology • Data quality • Stylesheet issues • TIME

5. Standards - what standards??? • Interface standards/output formats in Wigan • HL7 v2 (various implementations of) • EDIFACT • ASTM • System specific output – eg. Torex PAS openlink • Acute Trusts need to learn to work with what’s available !!!

6. Implementation issues - PAS • PAS ‘real-time’ interface • No guarantee that messages would be delivered in the right order • Could get an Admission message prior to a Patient Registration • Had to introduce a 15 minute time delay • Result: bed-status in EPR system slightly out of sink

7. Implementation issues - Pathology • Handling previous results – append or overwrite? • Microbiology – overwrite • Haematology, Chemistry – currently append • Collection date and time not always supplied • Reference ranges can change • Implication for graphing • Sensitive tests • What is the best way to deal with HIV, GUM, pregnancy tests etc?

8. Implementation issues - Pathology • Multiple patient IDs (NHS number, Hospital number) • Multiple casenote numbers (Trust mergers) • Need to establish systems for cross referencing patient IDs • Missing patient ID • Pathology system sending internal patient ID • Missing key patient data – DOB, Gender • Unable to guarantee a match – need to Dump message

9. Data Quality • Biggest issue by far is unique person referencing • Major education / change mgmt task to • Get patient administration staff to register patient details accurately and avoid duplicates • Get clinicians to use the Hospital / NHS Number • Problem especially big in emergency care • Issue has a huge knock on effect for the remainder of each episode care

10. Data Quality Example:A consultant asked me to investigate why a particular chemistry result did not appear in the patient’s EPR recordIn this instance the patient ID recorded in the Hospital Number field turned out to be the patient’s telephone number MSH|^~\&|MLAB||||20040519113446||ORU^R01|X99156|P|2.3 PID|1||217779^^^^PAS~773702^^^^DEP||SURNAME^FORENAME^^^||19371113|M|||999ACACIAAVENUE^ORRELL^WIGAN^^WN99XX||||| ZMP|G3417810^^NAT^SS^^L|^^L ZPV|AE|CAS^^^MLAB&RAEI&L^^W|&AP^PINTO^A.^^^Mr.|CAS^^^MLAB&RAEI&L^^W|&AP^PINTO^A.^^^Mr.|ACC|CC|CH|20177803|20040519|200405191026||FITS.|U||P OBR|1||20177803^CCMLAB|CC_RUEGK^Urea, Elects. Gluc (urgent)^L^^^L|||20040519||||||FITS.|200405191026||&AP^PINTO^A.^^^Mr.||||||||CH|F||^^^20040519^S| OBX|1|ST|CC_TONA^Sodium^L^44I5.^^RC||140|mmol/L|135-145|N|||F Lesson: CANNOTuse patient ID as the sole identifier – also need to cross reference with patient’s DOB, Gender, Surname …

11. Addressing data quality issues in Casualty • Solution Integrated emergency floor system • New emergency floor system is integrated with PAS to enable staff to retrieve up-to-date patient demograhics, including NHS Number • New emergency floor Pathology / X-ray requests automatically include patient ID - improvement departmental system data quality • New emergency floor system will be able to automatically register new patients on PAS - improvement 24 hour bed status

12. Integrated emergency system live Addressing data quality issues in Casualty

13. Issues that are not so easy to address … Addressing data quality issues in Casualty • Real-time data capture • Not easy when an A&E receptionist is face to face with a patient who is either • Confused • Uncooperative • Abusive • Unconscious • Addressing these issues is proving to be a much more challenging task!!!

14. Addressing presentation issues using XSL Stylesheets Rapid application development approach : (1) Present the HL7 results in the EPR test system environment via a stylesheet, and ask the domain experts for comments (2) Amend stylesheet, and repeat (1) until domain experts are happy to sign off stylesheet design (3) Implement stylesheet in live EPR system

15. Microbiology example - Legacy Pathology System view Sensitivities in a fairly non user-friendly cross tabulation format

16. HL7v2 messages A Culture and Sensitivity result is reported using multiple OBX segments. A single organism result comprises an Organism OBX segment with subID N followed by an Organism Growth OBX segment with subID N followed by zero, one or more Organism Sensitivity OBX segments also with a subID value of N.

17. Microbiology The final stylesheet design was deemed an improvement to the legacy system text based screen More user-friendly cross tab for Organism vs Sensitivities

18. Critical issue - TIME • Building interfaces is not a 5 minute job • Tasks TIME • Find funding to initiate project ? (show-stopper?) • Design interface, agree end-to-end requirements 1-3 months ? • Supplier set-up / configure interface 1-3 months ? • NHS Trust set-up / configure interface 1-3 months ? • End-to-end testing 1-3 months ? • On-going Stylesheet development ? • In summary, even a bog-standard unidirectional HL7 interface could take anything from 3 to 15 months, from start to finish

19. Key benefit of basing your integration architecture around XMLEXCHANGE OF BOTH DATA AND PRESENTATION

20. Data and Presentation • Web technology is enabling the Trust to benefit from both Data exchange: development of interfaces which move XML patient data between an EPR (an XML clinical repository) and other departmental systems Presentation: development and sharing of stylesheets which present a common view of departmental system data across multiple applications

21. Data and Presentation ExampleBi-directional transfer of data and presentation between EPR and A&E Discharge Letters, Emergency Care summary EPRElectronic Patient Records Emergency FloorElectronic Patient Records JOIN Shared XML data and stylesheets Pathology results, Patient demographics

22. Haematology result in the EPR system

23. Haematology result in the A&E system

24. Addressing issues andPlanning ahead for HL7 v3 messaging

25. Emergency Floor system design • Change management issues • A&E clinicians had never previously entered clinical data into a computer – all notes were recorded on a paper cascard • Solution had to be QUICK and USER-FRIENDLY !!! • Single screen to record all discharge information • Order comms – all requests for investigations recorded • Treatment given – point and click • Drugs administered – point and click • Diagnosis – point and click • Clinician notes – free text

26. Emergency Floor system design Emergency Care System Simple / Quick point and click data capture

27. Emergency floor system Discharge screen auto generates an XML discharge summary message Stylesheets to produce 2 documents on discharge: (a) Patient letter (b) GP letter

28. Emergency floor discharge summaries • Discharge summaries are currently stored in raw XML and presented on screen using an XSL stylesheet • Diagnosis values are coded ICD10, but can easily be coded in SNOMEDCT as well • Raw XML can be transformed into valid HL7v3 A&E Encounter and Provision of care messages using XSLT prior to routing to the Spine

29. NPfIT Integration Challenges

30. Existing Systems Integration • Replacement of NHS IT systems will not happen overnight in Acute Hospital Trusts • Key department systems may not be replaced before 2010 • Existing systems integration is therefore a key issue for Acute Hospital Trusts

31. WWL / CSC NPfIT integration approach