Mandel – Fentanyl Shafer 1990

MATLAB Code

Implements the propofol model of Shafer et al.[1] with ke0 from Scott & Stanski.[2]

Contributed by Jeff E Mandel

function sys = fentanyl
% fentanyl model based on parameters from 
% Shafer, S. L., et al. "Pharmacokinetics of fentanyl administered by 
% computer-controlled infusion pump." Anesthesiology 73.6 (1990): 1091.
% Accuracy for patients outside the range 40-90 kg is unknown.
%
% ke0 from
% Scott, JAMES C., and D. R. Stanski. "Decreased fentanyl and alfentanil 
% dose requirements with age. A simultaneous pharmacokinetic and 
% pharmacodynamic evaluation." Journal of Pharmacology and Experimental 
% Therapeutics 240.1 (1987): 159-166.


    volume = ;        %Liters
    clearance = ;     %Liters/min
    n = length(clearance);
    ke0 = 0.147;
    EFFECT_VOL_FACTOR=10000; % ratio of central compartment vol to effect
    k1 = [clearance./volume(1) ke0/EFFECT_VOL_FACTOR];
    k2 = [clearance(2:n)./volume(2:n) ke0];
    A = [-sum(k1) k2;transpose(k1(2:n+1))-diag(k2)];
    B = [1;zeros(n,1)];                   % Direct addition of drug into the central compartment
    C = [zeros(1,n) EFFECT_VOL_FACTOR/volume(1)];     % Observation of the effect site compartment concentration.
    C = C./1000; % All compartment volumes are in L, convert to ml
    D=0;

    sys=c2d(ss(A,B,C,D), 1/60,'zoh');
end