Let
$K$ be a knot in
${{S}^{3}}$ . This paper is devoted to Dehn surgeries which create 3-manifolds containing a closed non-orientable surface
$\hat{S}$ . We look at the slope
$p/q$ of the surgery, the Euler characteristic
$\mathcal{X}(\hat{S})$ of the surface and the intersection number
$s$ between
$\hat{S}$ and the core of the Dehn surgery. We prove that if
$\mathcal{X}(\hat{S})\,\ge \,15\,-3q$ , then
$s\,=\,1$ . Furthermore, if
$s\,=\,1$ then
$q\,\le \,4\,-\,3\,\mathcal{X}(\hat{S})$ or
$K$ is cabled and
$q\,\le \,8\,-5\mathcal{X}(\hat{S})$ . As consequence, if
$K$ is hyperbolic and
$\mathcal{X}(\hat{S})\,=\,-1$ , then
$q\,\le \,7$ .