Step 1: Simplify the integrand.
We have
\[
\frac{x^8+4}{x^4-2x^2+2}.
\]
By polynomial division,
\[
x^8+4=(x^4-2x^2+2)(x^4+2x^2+2).
\]
Therefore,
\[
\frac{x^8+4}{x^4-2x^2+2}=x^4+2x^2+2.
\]
Step 2: Integrate the simplified expression.
Now,
\[
\int \frac{x^8+4}{x^4-2x^2+2}\,dx
=
\int (x^4+2x^2+2)\,dx.
\]
So,
\[
\int (x^4+2x^2+2)\,dx
=
\frac{x^5}{5}+\frac{2x^3}{3}+2x+K.
\]
Step 3: Compare with the given expression.
Given,
\[
\int \frac{x^8+4}{x^4-2x^2+2}\,dx=Ax^5+Bx^3+Cx+K.
\]
Comparing,
\[
A=\frac{1}{5},\quad B=\frac{2}{3},\quad C=2.
\]
Step 4: Find \(5A+3B+C\).
Now,
\[
5A+3B+C
=
5\left(\frac{1}{5}\right)+3\left(\frac{2}{3}\right)+2.
\]
\[
=1+2+2.
\]
\[
=5.
\]
Step 5: Final conclusion.
Therefore,
\[
\boxed{5}
\]