Lessons learned from a lifetime with Electronic Medical Records

Transcription

1 Lessons learned from a lifetime with Electronic Medical Records Sao Paulo, Brazil Clement J. McDonald MD 1

2 Disclaimer These remarks are based on my opinion and experience and do not necessarily represent an official opinion or position of the National Library of Medicine or NIH 2

3 Topics for today Some background EMRs: Regenstrief medical record system (RMRS0 Decisions support: Reminders from the RMRS pre-order entry Physician Order entry: Regenstrief Gopher system 3

4 Topics more Standards today HL7 LOINC The Indianapolis Network for Patient Care (INPC) 4

5 Some Background 5

6 The early dreams of many/most medical Informatician Wanted to automate the proud core of medicine Diagnosis Patient Management Discovery 6

7 Example-1 Homer Warner (the first) Wanted to the computer to diagnose Used Bayes Theorem- to convert information about the prevalence of symptoms by disease into the probability of the disease given a set of symptoms Warner HR, et al.. A mathematical approach to medical diagnosis. Application to congenital heart disease. JAMA Jul 22;177:

8 Examples-2 In the early 70 s Howard Bleich wanted to apply expert advice to the management of acid base therapy. Bleich HL: The computer as a consultant. NEJM 1971; 284:

9 Me too I was a freshman in Medical School when Homer Warner s paper came out and it caught my imagination In as a senior med student- I tried to replicate his approach on the acute abdomen. (Plop) In I tried some more and made it my master s thesis ( double Plop) 9

10 More Pauker SG, Gorry GA, Kassirer JP, Schwartz WB. Toward the simulation of clinical cognition: Taking a present illness by computer. Am J Med 1976; 60:

11 Lessons learned 11

12 The Curse of high dimensions Became obvious early in the life of computer diagnosis 1 Can t get enough cases to populate the cells of a the conditional probability Analogous problem (Sample size) in statistics 1. Warner 1963 JAMA 12

13 The question of Diagnosis may also be mis-stated The goal is to decide what to do next- not (Necessarily) pick a Diagnosis treat empirically, test some more, Wait 13

14 Some neat papers with insight Pauker SG, Kassirer JP. The threshold approach to clinical decision making. New Engl J Med 1980; 302: Blois MS: Clinical judgement and computers. N Engl J Med 1980; 303:

15 Research is the process of going up alleys to see if they are blind Marston Bates 15

16 Now what Let s collect the data needed to feed decision support and other purposes Needed data about the patient wihtin the computer to trigger a response to abnormal patient states. 16

17 Me too I did the same at Regenstrief starting in

18 Build an EMR to get the needed data Homer Warner was very explicit about this- Can t get the data needed to produce the statistics needed for Bayes theorem- so lets collect it with an EMR The HELP system at LDS and now Intermountain Health care Howard Bleich and Warner Slack did the same at Beth Israel Hospital Ed Hammond and Bill Stead ditto at Duke - The Medical Record (TMR) 18

19 My hopes for (Electronic Medical Record systems Goals 1972) 1. Solve the Logistic problems of paper records Always available, well organized and legible 2. Relieve MDs of clinical book keeping work decision support 3. Unlock the research potential of the medical record room 19

20 Equipment back then PDP 11/44 computer 32K of core memory 10 Million bytes of disc 4 computer lines About $140K per 73 budget ( $1 M in today's dollars) It was heaven No keypunch cards No 2 hour waits to find one typo In 1972 DEC BASIC was far ahead of MS BASIC in the 80 s 20

21 1975 PDP West OPD 21

22 1975 printer 10 Characters Per Second 22

23 Encounter form for Op Scan 17 23

24 Collected data by off line entry and Op Scan 17 optical form reading Required use of pencil or black ink Users had to write on the window sash lines Got 95% accuracy Form had to be printed in special OCR invisible ink 24

25 Close up Op Scan 17 digit entry 25

26 Decision Support Simple rules about preventive care and needed treatments 26

27 Time line 1974 operational rule-based reminder system st randomized trial showing benefit of computer reminders. (New Eng J Med 1976) 27

28 Regenstrief Informatics History st clinical exchange standard (ASTM handout) st (only) Randomized trial of CPOE - Tierney JAMA st beginning city-based network 1995 LOINC a code system for clinical variables. The first clinical code system standard to be adopted by the government. 28

29 1976: Computer reminders presented as printed reports at visit MD Response with Reminders 51%, 327 events Response without Reminders 22%, 385 events P<0001 Computer reminders & Non-perfectibility of man. NEJM 1976;295:

30 1984: biggest reminder study ever Similar approach much larger scope Applied 1400 rules to 50,000 visits Similar sized effect as

31 : Effect of reminders by suggested action Occult Blood Cervical Pap Hematocrit Chest Xray Pneumovax TB Skin Test Serum K Mammography Flu Shot Diet Reticulocytes FE/TIBC Digitalis Liver Enzymes Antacids McDonald, et al. Reminders to Physicians from an Introspective Computer Medical Record. 31 Annals of Internal Medicine, 1984;100: Control Study [RG] Percent Response

32 Physician Order Entry Medical Gopher at Regenstrief 32

33 1984 Gopher order entry system Could not reach any human at Digital research or Microsoft Used Revelation Pick operating system on a PC String oriented and integrated database like MUMPS Only language vendor with anyone home 33

34 Early gopher installed in clinic 34

35 Early gopher mono screen 35

36 Notice Small screen- not many more pixels than Today's PDA Monochrome Some struggle getting started It worked 36

37 Lessons learned Speed is requirement not an option Less than 0.1 second field to field response time Very tailored order patterns- with good defaults Gradual installation so time for us to learn and improve --- started with test ordering only in one clinic Having a dedicated computer (client) per user provide huge speed improvement over central computer. 37

38 Many kinds of information can influence ordering Did a number of controlled trials Display of costs: chi-ching Computer generated likelihood that test would be positive Tierney & McDonald et al JAMA 1988 Randomized trial comparing POE to paper order entry- saved 13% on costs Tierney and McDonald JAMA 1993 Even default menus influence ordering 38

39 Effect of default to Q day frequency for Ceftriaxone Orders Changing default dosing frequency for ceftriaxone Orders/week BID QD Week 39

40 Live Reminders to physicians while they write orders Many studies Most showed important effects Advantages of active reminders during ordering process Best way to stop an order Context can be very clear when provider identifying problems Can, in principle ask for clarifying info 40

41 Preventive POE inpatient POE reminders % 50% 51% 40% 30% 20% 36% 32% 19% 36% 27% reminders control 10% 0% 0.80% 1% pnevx flu shot SQ Hep ASA Dexter PR, et al. A Computerized Reminder System to Increase the Use of Preventive Care for Hospitalized Patients. N Engl J Med 2001;345:

42 Nursing standing orders for preventive care Hospital committed to rule for standing orders Computer reminds nurse as part of discharge procedure when patient needs flue shot or pneumonia vaccine Nurse verifies with patient that They have not had No allergies They accept Then dispense Even larger effect than MD reminders (not 100%) Dexter JAMA

43 Gopher POE as of million orders- in one hospital Lots of publications Lots of users 43

44 Gopher physician Users 44

45 Today Gopher Physician Users 45

46 What have we proven with reminders Men more frequently require to be reminded than informed. Samuel Johnson,

47 What we learned Difficult to develop rules you can follow AND you can trust Too many weasel words in guidelines Rules not always based on any evidence Airport experts Difficult to construct and implement rules for even modestly complicated realities 47

48 What we have learned Some easy to implement rules Immunizations Start cholesterol lowering drugs Heart failure meds (ACE inhibitors, Beta Blockers) Some anticoagulation situations Lots of administrative issues. 48

49 What we have learned 2 Getting extra questions answered is difficult User may not know Always in a hurry Have to be very careful with the specificity of rules Rules work best when process in place to collect (and verify) triggering information- to assure High specificity Able Kho JAMIA (rules about isolatoin) 49

50 Guidelines are often useless as rule Decidability Correctness sources Guidelines you can follow and can trust: an ideal and an Example JAMA 1994:271:

51 Two kinds of problems The rules are wrong (looking back) Avoid Nitroglycerin during Acute MI Experts don t always know what is true Rules are not matched to complexity of work flows The rule described too vaguely for computer use When patient taking diuretic- Measure Serum Potassium at suitable intervals. Use broad spectrum antibiotics when patient is critically ill 51

52 Work flow issues Write order for medicine that is dosed by body surface area. Needs height and weight ( ideally) Provider writes order- Computer asks for patient height Provider does not know by heart all patient s height Many patients have not had height recorded in chart Should have been collected ahead of time But that has same problems 52

53 Representing rules Decisions tables, pseudo code, very clear and decisive prose are good Flowcharts are bad 53

54 Flowchart-Lousy way to represent anything 54

55 Pseudo-code Heparin is started and adjusted according to the patient's weight and the last APTT IF starting heparin drip THEN Give kg based bolus. Adjust the dose by protocol IF APTT < 35 THEN Give 80/kg bolus and increase drip by 4 units/kg.h... Repeat APTT in 6 hours 55

56 Prose statement (Ottawa ankle rules) An ankle radiographic series is only required if : there is any pain in malleolar zone and any of these findings: 1. bone tenderness at A 2. bone tenderness at B 3. inability to bear weight both immediately and in ED 56

57 Great Source chest The journal, Chest Has every 3 year recommendations on anticoagulation recommendations Can be translated directly into Decision logic Written as decidable prose 57

58 CARE IF TODAY IS NOT AFTER 10/1 & BEFORE 12/31 OR "FLU SHOT LAST" IS AFTER 8/1 OR LAST "REFUSED FLU INJ" WAS = 1 & SINCE 1 YEAR AGO OR "DRUG ALLERGIES" WAS = "SERUM ALRGY" THEN EXIT IF "AGE" IS GT 65 THEN Consider use of "flu shot AB" if no egg allergy because age places patient in high risk category AND EXIT IF "X LAST" WAS = ASTHMA" V "COPD" OR "CHEST X-RAY LAST" WAS = "COPD" THEN Consider giving "flu shot AB" if no egg allergy because patient's lung disease places him in high risk category. R:2124 AND EXIT 58

59 Need for standards 1983 Getting the data in to our EMR took most of the work For some systems it was really tough Needed standard export messages Was clear only crazy people or medical Informatician would build EMRs 59

60 1984 standards proposal from SCAMC paper Looks a lot like today s HL7 Patient 1 (general information about patient) Battery 1 (information about battery1 request) Result 1 (information about the first result of battery 1) Result 2 (information about the second result of battery 1) i Result n (information about the last result of battery 1) Battery 2 (information about battery 2) Result 1 (information about the first result of battery 2) Result 2 (information about the second result of battery 2) i Result n (information about the last result of battery 2) i Battery n (information about the last battery for the first patient) Result 1 (information about the first result of the last battery) Patient 2 (all of the structure repeats) i 60

61 Standards ASTM/HL SCAMC proposed standards 1988 ASTM first published consensus message standard HL7 and ASTM versions merged McDonald CJ. Standards for the transmission of diagnostic results from laboratory computers to office practice computers -- an initiative. Proc Annu Symp Comput Appl Med Care 1983; McDonald CJ, Wiederhold G, Simborg DW. A discussion of the draft proposal for data exchange standards for clinical laboratory results. Proc Annu Symp Comput Appl Med Care 1984; McDonald CJ, Blevins L, Tierney WM, Martin DK. The Regenstrief Medical Records. MD Comput Sep-Oct; 5(5):

62 Vocabulary standards Had to have a standard code to identify the observation from outside of the organization LOINC to the rescue We talked about it yesterday Type in LOINC on Google to get to the web side and down load what every you want. 62

63 LOINC what is it Data base of clinical observations (questions) with answers (Some) And.. Other attributes Question dissected into parts Parts tied to synonyms, short names and definitions and references and source (Some) Questions aggregated into data collection forms 63

64 LOINC what s in it 50,000 observations and forms Language translations ReLMA program for mapping to, and browsing, LOINC content Program for generating local data base of terms from HL7 message stream 64

65 Example of LOINC form 65

66 LOINC Chinese of Users guide Translation 观 测 指 标 标 识 符 逻 辑 命 名 与 编 码 系 统 (LOINC ) Logical Observation Identifier Names and Codes (LOINC ) 用 户 指 南 Users' Guide LOINC 版 权 声 明 与 许 可 协 议 (LOINC Copyright Notice and License) LOINC 代 码 LOINC 用 户 指 南 及 LOINC 数 据 库 版 权 所 有 Regenstrief Institute, Inc.(Regenstrief 研 究 院 股 份 有 限 公 司 ) 及 Logical Observation Identifiers Names and Codes (LOINC) Committee( 观 测 指 标 标 识 符 逻 辑 命 名 与 编 码 系 统 委 员 会,LOINC 委 员 会 ) 保 留 所 有 权 利 LOINC 属 于 Regenstrief Institute, Inc. 的 注 册 商 标 在 符 合 下 列 条 款 的 情 况 下, 特 此 永 久 准 许 出 于 任 何 商 业 性 或 非 商 业 性 目 的 而 使 用 拷 贝 或 分 发 LOINC 代 码 LOINC 用 户 指 南 及 LOINC 数 据 库 者, 无 须 支 付 许 可 费 用 或 版 费 : 66