13 yr old Jack Russell Terrier very sick!! Please help!!!

A month ago, my 13 year old Jack Russell Terrier suddenly got very sick (she has NEVER been sick before, has always been energetic and active until this episode).  She started vomiting bile violently and having diarrhea (no blood).  I took her to the emergency, she was given shots to stop the vomiting and diarrhea.  She seemed to get better after a few days.  However, since then she has become very lethargic, has lost a lot of weight, has no energy, sleeps all day, loses her balance, vomits once or twice every few days (seems to get better then vomits again but no diarrhea).  I have taken her back to the vet, they did a blood test, and confirmed she has an infection of some sort (white blood cell count is higher, we don't know what's infected).  Her liver and kidney blood indicators are OK.  The vet has put her on antibiotics to fight the infection, and also special food and meds to calm her stomach.  However, the worst part is that she has started collapsing/fainting every time she gets startled and attempts to run/bark!  It has happened 3 times in the last week now, a raccoon startled her on her walk, she ran/barked and then collapsed, stopped breathing and came back to after a few seconds.  She does have a heart murmur and I am afraid is getting heart failure now (note she is not coughing).  The vet would like us to bring her in for x-rays first to determine if her heart is enlarged but we'd need to leave her at the vet's office for a whole day.  She is extremely afraid of the vet as it is and freaks out even when healthy, and we've never left her alone at the vet.  I am afraid leaving her might cause a heart attack and kill her as she's very weak!  Is there anyway to diagnose for heart conditions without an x-ray???  Should they be putting her on heart meds regardless of the x-ray???  PLEASE HELP!!!

[Jaybay]

Your vet is right and your dog needs to have the x-rays done.  Some dogs need to be sedated for x-rays anyway, so ask if it's safe to have your dog mildly sedated while she's there.  You'd be surprised how quickly the anxiety passes when owners leave the office.  Our dogs pick up on our anxiety and because they don't understand why we're anxious, they believe there really is something to be scared of.  The best thing you can do for her is to stay very calm when you drop her off.  Just act like it's completely normal for her to have a day away from home.  You can fall apart after you leave.  :-)