Dear Group,
I am probably revisiting this issue.
I am working on a study where the blood samples are collected at steady-state.
Subjects are samples for pre-dose blood sample and 4-6 samples after clinic
observed doses (typical way). The prior-dose to the clinic visit was not
recorded. I would like to use the A_0 option to estimate the initial central
compartment amount as a parameter along with BSV. I set SS=2 at the dosing
event so that the compartment amounts not to be reset to zero but that the
compartment amounts are to be set to the sum of the steady-state amounts
resulting from the given dose plus whatever those amounts would have been at
the event time were the steady-state dose not given. Can somebody explain how
NONMEM actually calculates the A_0 of a compartment when SS=2 or SS=3 given and
also comment on the information does that parameter give more than the trough
concentration measured at the clinical visit?
Regards,
Ayyappa
COMPARTMENT INITIALIZATION: A_0
I cannot understand or answer most of your questions.
The Exogenous supplementation example uses SS with modeled rate to model
an unknown dosing history prior to the observation period (i.e.,
prior to time zero). All compartments receive the appropriate amount
from the SS dose, not just the central compartment. A_0 is not used.
Quoted reply history
On Tue, Mar 27, 2012, at 03:43 PM, Ayyappa Chaturvedula wrote:
Dear Group,
I am probably revisiting this issue.
I am working on a study where the blood samples are collected at steady-
state. Subjects are samples for pre-dose blood sample and 4-6 samples
after clinic observed doses (typical way). The prior-dose to the clinic
visit was not recorded. I would like to use the A_0 option to estimate
the initial central compartment amount as a parameter along with BSV. I
set SS=2 at the dosing event so that the compartment amounts not to be
reset to zero but that the compartment amounts are to be set to the sum
of the steady-state amounts resulting from the given dose plus
whatever those amounts would have been at the event time were the
steady-
state dose not given. Can somebody explain how NONMEM actually
calculates the A_0 of a compartment when SS=2 or SS=3 given and also
comment on the information does that parameter give more than the trough
concentration measured at the clinical visit?
Regards,
Ayyappa
--
Alison Boeckmann
[email protected]
Alison,
Thank you for the response, it is helpful.
Regards,Ayyappa Chaturvedula
Quoted reply history
On Mar 29, 2012, at 1:59 PM, "Alison Boeckmann" <[email protected]
> wrote:
> I cannot understand or answer most of your questions.
>
> The Exogenous supplementation example uses SS with modeled rate to
> model
> an unknown dosing history prior to the observation period (i.e.,
> prior to time zero). All compartments receive the appropriate amount
> from the SS dose, not just the central compartment. A_0 is not used.
>
> On Tue, Mar 27, 2012, at 03:43 PM, Ayyappa Chaturvedula wrote:
>
> Dear Group,
>
>
> I am probably revisiting this issue.
>
>
> I am working on a study where the blood samples are collected at
> steady-
> state. Subjects are samples for pre-dose blood sample and 4-6 samples
> after clinic observed doses (typical way). The prior-dose to the
> clinic
> visit was not recorded. I would like to use the A_0 option to
> estimate
> the initial central compartment amount as a parameter along with
> BSV. I
> set SS=2 at the dosing event so that the compartment amounts not to
> be
> reset to zero but that the compartment amounts are to be set to the
> sum
> of the steady-state amounts resulting from the given dose plus
> whatever those amounts would have been at the event time were the
> steady-
> state dose not given. Can somebody explain how NONMEM actually
> calculates the A_0 of a compartment when SS=2 or SS=3 given and also
> comment on the information does that parameter give more than the
> trough
> concentration measured at the clinical visit?
>
>
>
> Regards,
>
> Ayyappa
> --
> Alison Boeckmann
> [email protected]
>