Dear FTP,
Yes. I can see why you think there is something more to the eye in Dietz’s left hand (see below). However, if I recall correctly, Dick Smith said the vomit contraption actually connected behind Dietz’s head. This probably meant the contraption was completely out of sight, perhaps under the pillow which led to the powerful pump necessary. Of this I cannot be certain. I looked this picture over to find this crucial element of which you speak, but I can’t find anything out of place; e.g., intravenous tube strapped to the blue restraint board and the two pieces of medical tape to secure the IV in Regan’s arm should be there. Therefore, I am posting the pic of that particular scene for your perusal (hopefully, you will see something I can’t).
On another note, the very next time in the film that we see Regan’s left hand is when the restraining strap rips apart through “demonic rage” or whatever name you wish to call it. In this shot, notice the difference in the strap’s relationship to the hand and the lack of elements I indicated above. Compare the pictures and you will see that things do are out continuity context.
Click the pictures to enlarge if you wish.
FB

