Setings from godknight 420 e

Hello :

Can someone explain the menu seetings from GoodKnigh 420 e...

Thanks a Lot

Luis,

Luis,

I am not sure we understand what you want explained.

Is it how to access the clinical menu ?

Is it you want us to explain particular menu entries ? (if so, which ones)

Cheers

DSM

exp :

Max comand for apnea ....

Luis,

"Max pressure command for apnea" (in the advanced settings of the PB 420E) should not be changed except for very unusual cases. You should leave the "Max pressure command for apnea" on the factory setting of 10. Don't change that setting.

That setting is a safety cap to prevent the 420E from using more and more and more pressure if the apnea is actually a "central" apnea instead of an obstructive apnea.

Here are some rather technical discussions about that setting by a very knowledgable poster nicknamed -SWS.

Excerpt from one of -SWS's posts on page two of this clickable link to a previous topic:

Jan 11, 2005 subject: Bman: Spirit Overnight Indices


"The 420e has three notable adjustable parameters the other models do not: 1) IFL1 (flow limitation runs), 2) IFL2 (individual flow limitations that are concomitant with hypopneas), and 3) command-on-apnea. Those first two are optional triggers that jointly yield four unique combinations of treatment. That last one is a pressure response "safety cap" toward the avoidance of central apneas. Contrary to popular myth, command-on-apnea is the 420e's primary means of avoiding central apneas. With a sensitivity rating of 62%, CA detection via measuring cardiac oscillations is but an augmentary method. With the command-on-apnea setting at its default of 10 cm, most patients will not pressure-induce "runaway" centrals. However, cardiac oscillation detection will catch 62% of any and all central apneas that happen to sneak under that 10 cm safety cap."

Farther down in that same thread, -SWS explains more about the "Max pressure command for apnea" trigger:

"That third adjustable parameter is really best thought of as an AutoPAP pressure-response "safety limit" or "safety cap" to help in the avoidance of pressure induced central apneas (which can easily escalate in some patients, manifesting in a condition referred to as "runaway" central apneas). This "command on apnea" setting is defaulted at 10 cm on the 420e. That 10 cm default limt has very sound statistical basis across the apneic patient population with respect to air pressures at which central apneas are known to manifest in significant numbers. There are only two scenarios that I can think of in which a therapist would need to adjust this "command on apnea" parameter: 1) significant occurences of pressure-induced central apneas at or below 10 cm (in which case the patient might ultimately require a BiLevel machine specifically designed to "treat" central apneas), or 2) a patient requiring more than 10 cm pressure to reactively (not proactively) clear his/her obstructive apneas and that patient shows absolutely no signs of inducing "runaway centrals" at those higher "apnea responsive" pressures."

In a later post, -SWS corrected his statement of the PB's specificity/sensitivity percentages regarding central apneas:

Jan 08, 2005 subject: 420e Specification Correction

"In a past post I erroneously said that the 420e's central apnea specificity was on the order of eighty-some percent. I just now reviewed the 420e central apnea specs and here they are:

420e Central Apnea Specificity=100%
420e Central Apnea Sensitivity= 62%"

As I understand it...

The 62% Sensitivity means some central apneas will not be identified and will slip by unmarked.
The 100% Specificity means any time the PB 420E auto DOES mark an event as a "Ca" it is for sure a Central Apnea.

Ca = Apnea with cardiac oscillations, meaning the machine can discern a heartbeat. If the machine can sense a heartbeat during an apnea, that means the throat is open. Open throat with stopped breathing = central apnea.

RG (and SWS), thank you for the excerpts and the additional explanation. I was also a bit puzzled by this setting and wondered why it wasn't equal to the maximum pressure setting.