Thank you for your question regarding your 3 year old lab girl who has been pacing and unable to sleep tonight. As you can probably appreciate, there are quite a number of possible causes for her symptoms including anything from early gastroenteritis, to a toxicity (hopefully there isn't anything she could have gotten in to today?), to even an internal organ or endocrine problem (although less likely given her age). While a urethral obstruction is possible (secondary to bladder stones and crystals for example), this is extremely uncommon in female dogs given their wide and short urethra compared to male dogs. As such, I do think a urethral obstruction is unlikely, and typically you would see your girl straining to urinate, rather than not attempting anything at all. Whatever the case here, if your girl's symptoms don't settle in the next hour or two, you are best to play it safe and get her seen by your local ER vet tonight.
Over the next few hours, please keep an eye on her mucus membranes, capillary refill time and respiratory rate tonight 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.
If your girl does start straining to urinate, or if any of the above parameters aren't right, then you really are best to get your girl seen tonight if you can. If all is well overnight, but she still hasn't urinated by the morning, you are best to follow up with your local vet to investigate further here. 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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