Progress on Guideline Expression Language

ASTM: Hypokalemia and Digoxin MLM

Sample Virtual EMR

/* read the potassium that evoked the MLM */ potassium := read last {potassium level}; /* get the last active digoxin or digitoxin order */ digoxin_order := read last {digoxin order}; /* read the potassium that evoked the MLM */ List all_potassium := select obs from Observation as obs where obs.service_cd.equals(new Concept(“MTH”, “C ”)) sort descending obs.critical_time.high; /* get the last active digoxin or digitoxin order */ List digoxin_orders := select meds from SubstanceAdministration as meds where meds.service_cd.equals(new Concept(“MTH”, “C ”)) and meds.isActive()==true; PhysicalQuantity hypokalemia_threshold := new PhysicalQuantity(3.3, “mEq/l”); Gello Arden Syntax OO Query

/* exit if the potassium value is invalid */ if potassium is not number then conclude false; endif; /* exit if there is no hypokalemia */ if potassium >= 3.3 then conclude false; endif; /* exit if indication of digoxin use cannot be found */ if (digoxin_order is null) then conclude false; endif; /* send an alert */ conclude true; PhysicalQuantity potassium := all_potassium.first_element().value(); /* alert if patient has hypokalemia and is on digoxin */ if (potassium.lt(hypokalemia_threshold) and not digoxin_orders.is_empty()) then conclude true; // send alert endif; conclude false; // do not send alert Gello Arden Syntax OO Expression

Discussion Based on OQL and TSQL Portable mapping to EMR Eliminates curly braces Query and expression writing can be simplified using editing GUIs templates and object navigators

Next steps Encode multiple MLMs to validate approach Refine language as needed Coordinate with virtual EMR project Help determine functions and attributes for vEMR objects Feedback from DSTC Authoring tools incorporating graphical programming aids