It's completely incorrect by any medical terms. He uses straight sewing needles instead of the curved◊ needles◊ used in real medicine. The worst part, though, is that he holds them in his mouth. That might be appropriate for a seamstress, but suture needles should always be sterile. The whole point of closing a wound with sutures is to stop bleeding and to stave off infection! And that, my friends, just bugs me.
To be fair, it's not like Zombie can get sick.
In addition, Hanna's not really that competent. I could easily see him holding hypodermics of infected blood in his mouth (by the plunger, not even he would be stupid enough to hold them by the needle), needles that he's using to sew a Not Using the Zed Word's arm back on are nothing. The straight needles could be explained by reason of the guy whose medkit it is is 1) used to having to treat paranormals, and 2) "is a hack with head trauma" (though I doubt the head trauma is really relevant at the moment).
I agree with the above there. Hanna's no doctor, what would he know?
Why would having to treat the paranormal mean that he wouldn't have proper medical needles?
The incorrect sutures are nothing compared to the other issue - that sewing the skin together does nothing to repair the bone.
ohno, we don't want the zombie to get sick. He might... oh wait. He's dead and a zombie, he's already dead and sick. So... who cares about proper medical procedures? If it bothers you, just pretend it's magical needle and thread.
Also, he probably learned any "medical procedures" from watching Worth, who is not exactly a shining Doctor. I can see Worth using a curved needle (Which by the way, Seamstresses use too) but definitely not considering whats sterile and what's not. In the page where Worth drops the organ, he gets mad, but promptly just picks it back up. It can probably be assumed that he still plans on using said organ on a client. So Hanna is not a doctor himself and the only example he has of one is not very good.
I'd be more concerned about Hanna getting sick, if he's putting the same needles that have been used to stitch up dead flesh in his mouth. Even if Zombie doesn't seem to be rotting much.
He's a zombie, what does it matter?. End of story.
If vampires need to be invited into a human's home, then how did Adelaide get into Conrad's apartment?
Could be a factor, but more than likely she was just more familiar with the loopholes one can use in such situations. Conrad is new to this deal. He doesn't carry around 'welcome' mat all time to place in front of doors, or sweet excuses for a brief invite.
To this, she probably could have somehow snuck he way in from Conrad opening a window when she was on the window (almost like letting her come in, even if not realising it) or you could say the loophole that its an apartment, and since Conrad rents and doesn't own the home, she has free reign.
If his apartment complex is a government owned housing project, it could be considered a public building.
Or she could simply be a more powerful vampire and can get around this.