These symptoms are definitely worrying, but as you can probably appreciate, there are quite a number of possible causes for these symptoms in your girl. The first thing to try and differentiate is whether your girl is coughing up the clear liquid, or vomiting it up. If it is coughing then we need to consider anything from lung or heart worm, to a primary cardiovascular issue (such as heart disease due to a valve problem), to an infectious issue like canine infectious cough to name a few potential causes. If this was vomiting on the other hand, then we need to consider a potential toxicity or poisoning, intestinal worms, an acute gastroenteritis, or even an internal organ issue.
You will definitely need to continue to keep a close eye on your girl, and you may need to move your appointment forward to tomorrow morning, rather than waiting until Thursday to follow up with your vet. For now, continue to encourage her to drink and hopefully she is drinking well and able to keep it down. If not - you may need to consider making up a fresh chicken broth for her. If you are pretty sure she vomited up the clear liquid rather than coughed it up, then you could try her with a little Pepcid. The typical dose for this type of situation is 0.25mg per pound of body weight up to twice daily. You can read more about the use of Pepcid in dogs online here: http://www.petplace.com/article/drug-library/library/over-the-counter/famotidine-pepcid
For the rest of the night, please keep an eye on her mucus membranes, capillary refill time and respiratory rate as follows (do be careful that your girl doesn't try to bite you):
Mucus membranes - flip her lip and look at the color of her gums. They should maintain a nice salmon pink color. Get her to the emergency Vet if they appear white or very pale pink, or if they are a dark deep red color.
Capillary Refill time - this measures blood perfusion and test this by putting your thumb on her gum to apply pressure. After you release your thumb you will see the gum blanch. Capillary refill time is the amount of time it takes (in seconds) for the gum to return to a healthy pink color from the blanched white color. If 2 seconds or less don't worry - if it is taking significantly more time, again - off to the emergency Vet.
Respiratory Rate - if she seems to be panting or breathing rapidly throughout the night, this is a sign of shock and or pain and a signal for a trip to the emergency Vet.
Best of luck with your girl, and if she is all fine throughout the night, I would definitely encourage you to follow up with your regular vet first thing tomorrow, rather than waiting until Thursday. I hope all of the above makes sense? If you have more questions or if I can help in any other way, please do not hesitate to ask! If you would like to accept my answer, please press RATE OUR CONVERSATION (I am not compensated in any other way). Bonuses are always welcome. Thanks! I hope to work with you again soon!
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