Page History

Mixed ambiguity with a conjunction:

• Concept
  t 199779004 |Persistent occipitoposterior or occipitoanterior position - delivered (disorder)|

   has 2 possible meanings, neither of which already existed in SNOMED CT at the time of writing, in 2021.
  
  The original meaning of this code dates back to ICD9: it is closely related to D660.3 DEEP TRANSVERSE ARREST AND PERSISTENT OCCIPITOPOSTERIOR POSITION DURING LABOR AND DELIVERY, a subtype of D660 OBSTRUCTED LABOR. This meaning was also originally reflected in SNOMED by its classification (back in 2002) as a subtype of 199746004 Obstructed labor (finding). From this archaeology, it becomes clear the "persistent" adjective in fact relates only to the "occipitoposterior presentation" permutation; the obstructed labour is unstated within the term but was implicit from the original taxonomy in both ICD and later in SNOMED.
  
  This leads to the following two possible meanings:
  
  
  • POSSIBLY_EQUIVALENT_TO xxxxxxxx Obstructed labour despite occipitoanterior presentation and now delivered
  • POSSIBLY_EQUIVALENT_TO yyyyyyyy Obstructed labour due to persistent occipitoposterior presentation and now delivered
• However, both of these are compound clinical statements that should not be added as active concepts but are required in order to satisfy the requirement to ensure clinically safe reporting of historical data.
• In addition, it is necessary to resolve the conjunction that arises from the original concept.

Resolution:

• Create 2 new concepts:

• • Inactivate 

    Concept
    t 199779004 |Persistent occipitoposterior or occipitoanterior position - delivered (disorder)|

    • POSSIBLY_EQUIVALENT_TO xxxxxxxx Obstructed labour despite occipitoanterior presentation and now delivered (disorder)
    • POSSIBLY_EQUIVALENT_TO yyyyyyyy Obstructed labour due to persistent occipitoposterior presentation and now delivered (disorder)

• Now resolve the 2 conjunctions:
  • Inactivate 

    Concept
    t xxxxxxxx | Persistent occipitoposterior presentation and now delivered (disorder)

    as a Classification concept
    • EQUIVALENT_TO 

      Concept
      t 199746004 |Obstructed labour (finding)|

    • EQUIVALENT_TO 

      Concept
      t 37235006 |Occipitoposterior position (finding)|

    • EQUIVALENT_TO 

      Concept
      t 236973005 |Delivery procedure (procedure)|

  • inactivate 

    Concept
    t yyyyyyyy | Obstructed labour due to persistent occipitoposterior presentation and now delivered (disorder)|

     as a Classification concept
    • EQUIVALENT_TO 

      Concept
      t 31041000119106 | Obstructed labour due to deep transverse arrest and persistent occipitoposterior position|

    • EQUIVALENT_TO 

      Concept
      t 236973005 |Delivery procedure (procedure)|