calc_fetal_phys: Calculate maternal-fetal physiological parameters

In httk: High-Throughput Toxicokinetics

Calculate maternal-fetal physiological parameters

Description

This function uses the equations from Kapraun (2019) to calculate chemical- independent physiological paramreters as a function of gestational age in weeks.

Usage

calc_fetal_phys(week = 12, ...)

Arguments

week	Gestational week
...	Additional arguments to parameterize_fetal_pbtk

Details

BW = pre_pregnant_BW + BW_cubic_theta1 * tw + BW_cubic_theta2 * tw^2 + BW_cubic_theta3 * tw^3

Wadipose = Wadipose_linear_theta0 + Wadipose_linear_theta1 * tw ;

Wfkidney = 0.001 * Wfkidney_gompertz_theta0 * exp ( Wfkidney_gompertz_theta1 / Wfkidney_gompertz_theta2 * ( 1 - exp ( - Wfkidney_gompertz_theta2 * tw ) ) ) ;

Wfthyroid = 0.001 * Wfthyroid_gompertz_theta0 * exp ( Wfthyroid_gompertz_theta1 / Wfthyroid_gompertz_theta2 * ( 1 - exp ( - Wfthyroid_gompertz_theta2 * tw ) ) ) ;

Wfliver = 0.001 * Wfliver_gompertz_theta0 * exp ( Wfliver_gompertz_theta1 / Wfliver_gompertz_theta2 * ( 1 - exp ( - Wfliver_gompertz_theta2 * tw ) ) ) ;

Wfbrain = 0.001 * Wfbrain_gompertz_theta0 * exp ( Wfbrain_gompertz_theta1 / Wfbrain_gompertz_theta2 * ( 1 - exp ( - Wfbrain_gompertz_theta2 * tw ) ) ) ;

Wfgut = 0.001 * Wfgut_gompertz_theta0 * exp ( Wfgut_gompertz_theta1 / Wfgut_gompertz_theta2 * ( 1 - exp ( - Wfgut_gompertz_theta2 * tw ) ) ) ;

Wflung = 0.001 * Wflung_gompertz_theta0 * exp ( Wflung_gompertz_theta1 / Wflung_gompertz_theta2 * ( 1 - exp ( - Wflung_gompertz_theta2 * tw ) ) ) ;

hematocrit = ( hematocrit_quadratic_theta0 + hematocrit_quadratic_theta1 * tw + hematocrit_quadratic_theta2 * pow ( tw , 2 ) ) / 100 ;

Rblood2plasma = 1 - hematocrit + hematocrit * Krbc2pu * Fraction_unbound_plasma ;

fhematocrit = ( fhematocrit_cubic_theta1 * tw + fhematocrit_cubic_theta2 * pow ( tw , 2 ) + fhematocrit_cubic_theta3 * pow ( tw , 3 ) ) / 100 ;

Rfblood2plasma = 1 - fhematocrit + fhematocrit * Kfrbc2pu * Fraction_unbound_plasma_fetus ;

fBW = 0.001 * fBW_gompertz_theta0 * exp ( fBW_gompertz_theta1 / fBW_gompertz_theta2 * ( 1 - exp ( - fBW_gompertz_theta2 * tw ) ) ) ;

Vplacenta = 0.001 * ( Vplacenta_cubic_theta1 * tw + Vplacenta_cubic_theta2 * pow ( tw , 2 ) + Vplacenta_cubic_theta3 * pow ( tw , 3 ) ) ;

Vamnf = 0.001 * Vamnf_logistic_theta0 / ( 1 + exp ( - Vamnf_logistic_theta1 * ( tw - Vamnf_logistic_theta2 ) ) ) ;

Vplasma = Vplasma_mod_logistic_theta0 / ( 1 + exp ( - Vplasma_mod_logistic_theta1 * ( tw - Vplasma_mod_logistic_theta2 ) ) ) + Vplasma_mod_logistic_theta3 ;

Vrbcs = hematocrit / ( 1 - hematocrit ) * Vplasma ;

Vven = venous_blood_fraction * ( Vrbcs + Vplasma ) ;

Vart = arterial_blood_fraction * ( Vrbcs + Vplasma ) ;

Vadipose = 1 / adipose_density * Wadipose ;

Vffmx = 1 / ffmx_density * ( BW - Wadipose - ( fBW + placenta_density * Vplacenta + amnf_density * Vamnf ) ) ;

Vallx = Vart + Vven + Vthyroid + Vkidney + Vgut + Vliver + Vlung ;

Vrest = Vffmx - Vallx ;

Vfart = 0.001 * arterial_blood_fraction * fblood_weight_ratio * fBW ;

Vfven = 0.001 * venous_blood_fraction * fblood_weight_ratio * fBW ;

Vfkidney = 1 / kidney_density * Wfkidney ;

Vfthyroid = 1 / thyroid_density * Wfthyroid ;

Vfliver = 1 / liver_density * Wfliver ;

Vfbrain = 1 / brain_density * Wfbrain ;

Vfgut = 1 / gut_density * Wfgut ;

Vflung = 1 / lung_density * Wflung ;

Vfrest = fBW - ( Vfart + Vfven + Vfbrain + Vfkidney + Vfthyroid + Vfliver + Vfgut + Vflung ) ;

Qcardiac = 24 * ( Qcardiac_cubic_theta0 + Qcardiac_cubic_theta1 * tw + Qcardiac_cubic_theta2 * pow ( tw , 2 ) + Qcardiac_cubic_theta3 * pow ( tw , 3 ) ) ;

Qgut = 0.01 * ( Qgut_percent_initial + ( Qgut_percent_terminal - Qgut_percent_initial ) / term * tw ) * Qcardiac ;

Qkidney = 24 * ( Qkidney_cubic_theta0 + Qkidney_cubic_theta1 * tw + Qkidney_cubic_theta2 * pow ( tw , 2 ) + Qkidney_cubic_theta3 * pow ( tw , 3 ) ) ;

Qliver = 0.01 * ( Qliver_percent_initial + ( Qliver_percent_terminal - Qliver_percent_initial ) / term * tw ) * Qcardiac ;

Qthyroid = 0.01 * ( Qthyroid_percent_initial + ( Qthyroid_percent_terminal - Qthyroid_percent_terminal ) / term * tw ) * Qcardiac ;

Qplacenta = 24 * Qplacenta_linear_theta1 * 1000 * Vplacenta ;

Qadipose = 0.01 * ( Qadipose_percent_initial + ( Qadipose_percent_terminal - Qadipose_percent_initial ) / term * tw ) * Qcardiac ;

Qrest = Qcardiac - ( Qgut + Qkidney + Qliver + Qthyroid + Qplacenta + Qadipose ) ;

Qgfr = 60 * 24 * 0.001 * ( Qgfr_quadratic_theta0 + Qgfr_quadratic_theta1 * tw + Qgfr_quadratic_theta2 * pow ( tw , 2 ) ) ;

Qfrvtl = 60 * 24 * 0.001 * Qfrvtl_logistic_theta0 / ( 1 + exp ( - Qfrvtl_logistic_theta1 * ( tw - Qfrvtl_logistic_theta2 ) ) ) ;

Qflvtl = 60 * 24 * 0.001 * Qflvtl_logistic_theta0 / ( 1 + exp ( - Qflvtl_logistic_theta1 * ( tw - Qflvtl_logistic_theta2 ) ) ) ;

Qfda = 60 * 24 * 0.001 * Qfda_logistic_theta0 / ( 1 + exp ( - Qfda_logistic_theta1 * ( tw - Qfda_logistic_theta2 ) ) ) ;

Qfartb = Qflvtl + Qfda ;

Qfcardiac = Qfartb ;

Qflung = Qfrvtl - Qfda ;

Qfplacenta = 60 * 24 * 0.001 * Qfplacenta_logistic_theta0 / ( 1 + exp ( - Qfplacenta_logistic_theta1 * ( tw - Qfplacenta_logistic_theta2 ) ) ) ;

Qfdv = 60 * 24 * 0.001 * Qfdv_gompertz_theta0 * exp ( Qfdv_gompertz_theta1 / Qfdv_gompertz_theta2 * ( 1 - exp ( - Qfdv_gompertz_theta2 * tw ) ) ) ;

Qfgut = Qfgut_percent / Qfnonplacental_percent * ( 1 - Qfplacenta / Qfartb ) * Qfartb ;

Qfkidney = Qfkidney_percent / Qfnonplacental_percent * ( 1 - Qfplacenta / Qfartb ) * Qfartb ;

Qfbrain = Qfbrain_percent / Qfnonplacental_percent * ( 1 - Qfplacenta / Qfartb ) * Qfartb ;

Qfliver = Qfliver_percent / ( 100 - ( Qbrain_percent + Qkidney_percent + Qgut_percent ) ) * ( 1 - ( Qfbrain_percent + Qfkidney_percent + Qfgut_percent ) / Qfnonplacental_percent ) * ( 1 - Qfplacenta / Qfartb ) * Qfartb ;

Qfthyroid = Qfthyroid_percent / ( 100 - ( Qbrain_percent + Qkidney_percent + Qgut_percent ) ) * ( 1 - ( Qfbrain_percent + Qfkidney_percent + Qfgut_percent ) / Qfnonplacental_percent ) * ( 1 - Qfplacenta / Qfartb ) * Qfartb ;

Qfrest = Qfcardiac - ( Qfplacenta + Qfgut + Qfliver + Qfthyroid + Qfkidney + Qfbrain ) ;

Qfbypass = Qfcardiac - Qflung ;

Value

list containing:

BW	Maternal body weight, kg
Wadipose	Maternal adipose fraction of total weight
Wfkidney	Fetal kidney fraction of total weight
Wfthyroid	Fetal thyroid fraction of total weight
Wfliver	Fetal liver fraction of total weight
Wfbrain	Fetal brain fraction of total weight
Wfgut	Fetal gut fraction of total weight
Wflung	Fetal lung fraction of total weight
hematocrit	Maternal hematocrit fraction of blood
Rblood2plasma	Maternal Rblood2plasma
fhematocrit	Fetal hematocrit fraction of blood
Rfblood2plasma	Fetal Rfblood2plasma
fBW	Fetal body weight, kg
Vplacenta	Volume of Vplacenta, L
Vamnf	Volume of amniotic fluid, L
Vplasma	Maternal volume of plasma, L
Vrbcs	Maternal volume of red blood cells, L
Vven	Maternal volume of venous blood, L
Vart	Maternal volume of arterial blood, L
Vadipose	Maternal volume of adipose, L
Vffmx	Fetal volume ofVffmx, L
Vallx	Vallx, L
Vrest	Maternal volume of rest of body, L
Vfart	Fetal volume of arterial blood, L
Vfven	Fetal volume of venous blood, L
Vfkidney	Fetal volume of kidney, L
Vfthyroid	Fetal volume of thyroid, L
Vfliver	Fetal volume of liver, L
Vfbrain	Fetal volume of brain, L
Vfgut	Fetal volume of gut, L
Vflung	Fetal volume of lung, L
Vfrest	Fetal volume of rest of body, L
Qcardiac	Maternal cardiac output blood flow, L/day
Qgut	Maternal blood flow to gut, L/day
Qkidney	Maternal blood flow to kidney, L/day
Qliver	Maternal blood flow to liver, L/day
Qthyroid	Maternal blood flow to thyroid, L/day
Qplacenta	Maternal blood flow to placenta, L/day
Qadipose	Maternal blood flow to adipose, L/day
Qrest	Maternal blood flow to rest, L/day
Qgfr	Maternal glomerular filtration rate in kidney, L/day
Qfrvtl	Fetal blood flow to right ventricle, L/day
Qflvtl	Fetal blood flow to left ventircle, L/day
Qfda	Fetal blood flow to Qfda, L/day
Qfartb	Fetal blood flow to Qfartb, L/day
Qfcardiac	Fetal cardiac output blood flow, L/day
Qflung	Fetal blood flow to lung, L/day
Qfplacenta	Fetal blood flow to placenta, L/day
Qfdv	Fetal blood flow to Qfdv, L/day
Qfgut	Fetal blood flow to gut, L/day
Qfkidney	Fetal blood flow to kidney, L/day
Qfbrain	Fetal blood flow to brain, L/day
Qfliver	Fetal blood flow to liver, L/day
Qfthyroid	Fetal blood flow to thyroid, L/day
Qfrest	Fetal blood flow to rest, L/day
Qfbypass	Fetal blood flow to Qfbypass, L/day

Author(s)

John Wambaugh

References

Kapraun, Dustin F., et al. "Empirical models for anatomical and physiological changes in a human mother and fetus during pregnancy and gestation." PloS one 14.5 (2019): e0215906.

httk documentation built on March 7, 2023, 7:26 p.m.