An arithmetic progression has a first term of 160 and a common difference of -8. What is the general term and the 8th term?

The sequence of systolic BP readings is $160, 152, 148, 136, 128 \text{ mmHg}$.
Let's find the differences between consecutive terms:
$152 - 160 = -8$
$148 - 152 = -4$
$136 - 148 = -12$
$128 - 136 = -8$
The differences are not constant, so the sequence as written is not a standard arithmetic progression. However, given the context of arithmetic progressions, it is highly probable that there is a typo in the sequence. The common difference appears to be $-8 \text{ mmHg}$ for most terms. We will assume the sequence is an arithmetic progression with a common difference of $-8 \text{ mmHg}$, meaning the third term 148 would ideally be 144 to fit this pattern.

Based on our assumption, the first term is $a_1 = 160 \text{ mmHg}$.
The common difference is $d = -8 \text{ mmHg}$.

The formula for the $n$-th term of an arithmetic progression is $a_n = a_1 + (n-1)d$.
Substitute $a_1 = 160$ and $d = -8$:

The general term is $\boxed{a_n = (168 - 8n) \text{ mmHg}}$.

The question asks for the BP after 8 hours, which corresponds to the 8th term ($n=8$) in the sequence.
Substitute $n=8$ into the general term formula:

The predicted BP after 8 hours is $\boxed{104 \text{ mmHg}}$.