# I have some errors in executing the following code, can anyone help me please?

2 views (last 30 days)
ammar toma on 10 May 2023
Moved: Torsten on 10 May 2023
% Define PK model parameters
infusion_rate = 200; % ug/kg/min
CL1 = 0.066; % L/min
CL2 = 0.6; % L/min
CL3 = 0.35; % L/min
V1 = 3; % L
V2 = 20; % L
V3 = 60; % L
% Define PD model parameters
ke0 = 0.19; % 1/min
ke1 = 0.07; % 1/min
ke2 = 0.04; % 1/min
EC50 = 2.2; % ug/mL
% Define time span and initial drug concentrations
tspan = [0 30]; % minutes
Cp0 = [0 0 0]; % ug/mL
Ce0 = 0; % ug/mL
% Define PK-PD model as an anonymous function
propofol_model = @(t, y) [ (infusion_rate - CL1 * y(1) - CL2 *(y(1) - y(2))/V1 - CL3*(y(1) - y(3))/V1)/V1; ...
(CL2*(y(1) - y(2))/V2); ...
(CL3*(y(1) - y(3))/V3)]; % PK model
pd_model = @(t, y) [ -ke0 * y(1) + ke1 * y(4); ... % Effect site 1
-ke1 * y(2) + ke2 * y(5); ... % Effect site 2
-ke2*y(3); ... % Effect site 3
(y(1) + y(2) + y(3))/EC50 - y(7)]; % PD model
% Solve the ODEs using ode45 solver
options = odeset('RelTol',1e-6,'AbsTol',1e-6); % Set solver options
[t, y] = ode45(@(t, y) [propofol_model(t, y(1:3)); pd_model(t, y)], tspan, [Cp0 Ce0], options);
% Plot PK and PD results
figure;
subplot(2,1,1);
plot(t, y(:,1), 'r', t, y(:,2), 'g', t, y(:,3), 'b');
xlabel('Time (min)');
ylabel('Drug concentration (ug/mL)');
legend('Central compartment', 'Peripheral compartment 1', 'Peripheral compartment 2');
title('Propofol PK Model');
subplot(2,1,2);
plot(t, y(:,7));
xlabel('Time (min)');
ylabel('Effect site concentration (ug/mL)');
title('Propofol PD Model');

Alan Stevens on 10 May 2023
You have no initial guesses for y(5) and y(7). And what about y(6)?

Torsten on 10 May 2023
Moved: Torsten on 10 May 2023
The vector of initial values
[Cp0 Ce0]
must have 7 elements, not 4.

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