Cat woes...all over again

Athena is recovering well from her kidney infection, though we had one grim evening when I tried to force down the pill I had discovered that I thought she had swallowed that morning. Lots of foaming at the mouth, scratching, and later, puking, ensued.But the timing is pretty bad, because before she got sick, she was scheduled for a teeth cleaning to see if a sore mouth was possibly the source of her not eating very well. Her teeth are pretty grungy, but there's no obvious abcess. She's been eating poorly for a while, which we thought at first was just pickiness. But now she seems very eager to eat when we put something in her bowl, and eats hungrily for about a bite, then goes and drinks lots of water. She's probably eating only a fourth to a third of what she needs to maintain her body weight, which is already a little on the slim side (and this from a cat who's been chunky for most of her adult life).Stephan and I leave for Hawaii a week from today, which is a trip that ironically, we made the airline reservations for the day that Varda, our other cat, died. We'd been planning the trip and knew using frequent flyer miles, we would have to plan ahead. That afternoon, I decided that we should go ahead and book the flight because we needed something to look forward to. I'm worried about leaving her for 10 days with her eating so little. Stephan's daughter, E., is a Vet Tech and will be looking in on her and giving her food and antibiotics twice a day. Thank goodness for that.But I think I'm going to take her in to the Vet's office again tomorrow and see how much she weighs, and if there is anything else we could try to get her to eat. We've talked about putting her on an appetite stimulant. I'd like to get to the root cause. If it's not her teeth, perhaps her stomach is giving her trouble. Her blood work always checks out great, no sign of kidney failure or anything else. Other than the poor eating, she's her usual teddy bear self who sleeps curled up around my head and likes to go out on her leash and harness in the yard when the weather is nice. She usually eats some grass when she goes out, which I know can be a sign that her stomach is upset.Tonight, Stephan cooked a chicken breast just for her, and I chopped it up very fine. This is Athena's favorite thing ever. She hungrily ate about a fork full before she went to drink some more water and then back upstairs to bed.Athena is 17 and I know that anything could happen at any time. But she's in such good health otherwise, I'd hate for something to happen that we could prevent or a problem go untreated that if treated, could give her another couple of happy years of cat retirement.I'm really not feeling so happy about going to Hawaii, though I've been planning and looking forward to this for months. I don't think we'll cancel the trip, but I feel a sense of urgency to try to get something about Athena's eating resolved before we go, so as not to return to an emaciated, malnourished, or very ill cat.