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Mapping Mechanical Ventilation Parameters


(Gigi Lipori) #1

I wanted to see if anyone might be able to advise on mapping of the clinical parameters below related to vents and anesthesia machines. I took a stab at some of them, but I’m not sure if they’re great matches. Additionally, I didn’t know how to go about the time parameters. I truly appreciate any thoughts, Gigi

Terms are below, and excel worksheet is attached.

ETCO2
ETCO2 - Oral/Nasal
PEEP
PIP
RESP DEVICE
RESP RATE
RESP RATE - Adult Mech
RESP RATE - Adult Spont
RESP RATE - Peds Mech
RESP RATE - Peds Spont
TIDAL VOLUME
TIDAL VOLUME EXHALED
VENT MODE - Adult
VENT MODE - Peds
VENT START TIME - Adult
VENT START TIME - Peds
VENT STOP TIME - Adult
VENT STOP TIME - Peds

vent terms.xls (27 KB)


(Vlad Korsik) #2

hello. here some insights from me

Why do not simply use Procedure occurrence table and populate procedure_concept_id with 4164571 45851008 Positive end expiratory pressure ventilation therapy, initiation and management instead of using Measurement table? The table maybe used to put extra parameters of PEEP, is it your use case?

As for me, it is better to evaluate source and find linked values, directly describes the Device applied in the clinical settings. After that - map these source_values to the Procedure domain.

The issue with time aspects is a tricky one(someone experienced may disagree probably )
If you need to preserve Start and End times of any event, here is my solution (NB for 6th CDM version)
a) To define start time use the procedure_datetime in Procedure occurrence table with for e.g. 4145647 266700009 Assisted breathing Procedure Standard Valid Procedure SNOMED
b) Store the end time in Value_as_datetime in Observation table and populate the observation_concept_id with 40482217 442137000 Completion time of procedure Observable Entity Standard Valid Observation SNOMED and use the field
observation_event_id
and obs_event_field_concept_id to modify the procedure, the first one will contain the exact id in the Procedure occurrence table to be detalized by the observation, the 2nd field specifies the exact filed in the Procedure table to be modified.
I will call for experienced guys to resolve the problem @Alexdavv @Dymshyts @zhuk @Polina_Talapova
, please give your thoughts plus corrections .


(Oleg Zhuk) #3

Hi, Gigi,
your mapping for ETCO2; ETCO2 - Oral/Nasal; PIP; RESP RATE; RESP RATE - Adult Mech; RESP RATE - Adult Spont; RESP RATE - Peds Mech; RESP RATE - Peds Spont is totally fine

For PEEP I would rather use 3022875 Positive end expiratory pressure setting Ventilator.
For TIDAL VOLUME I would rather use 21490854 Tidal volume Ventilator --on ventilator
For TIDAL VOLUME EXHALED I would rather go with 21490752 Tidal volume expired Respiratory system airway or something like that

Reasons to change mapping
  • From a clinical perspective, there are different ‘PEEPs’: one is intrinsic or auto-PEEP ( 3035822 Intrinsic PEEP Respiratory system), one is extrinsic PEEP or external PEEP, applied by ventilator ( 42528515 Extrinsic PEEP Respiratory system) And the third type is total PEEP, which is calculated by some ventilators with help of measured autoPEEP and external PEEP. However, you can’t always differentiate between all those types and mostly all you have is just a ventilator parameter - which, I suggest, would be 3022875.

  • Tidal volume is constant only in few modes of ventilation. Even during ventilation in these modes, measured TV can differ from set one. In most clinical situations this parameter is changing dynamically. In some cases desired tidal volume are not achieved with high inspiratory pressures and the ventilator delivers less volume. I am not familiar with your data (which mode of ventilation is used, are we talking about measured or set values, etc) that’s why I would rather change the mapping to a less granular concept

  • Your option for tidal volume exhaled is an alarm limit - real volume can be more, can be less, or can be equal to the alarm limit. TIDAL VOLUME EXHALED suggests that it is a real data, not an alarm limit

RESP DEVICE - what do you mean?

Ventilation duration problem: It’s been a while :slight_smile:
We always struggle to store a duration of something, but there are options: one was described by @Vlad_Korsik, another one (and even two) can be found here


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