So your dog just underwent surgery and everything seems to have went well, but now your dog is shivering and he feels cold, so next thing you know, you are on the Internet googling "help, my dog feels cold after surgery!" Of course, you are concerned, as all sorts of complications come to your mind, and you don't know what to do. Is your dog at risk for freezing to death? Is he in pain? Is he bleeding internally?
Fact is, most likely you have rarely seen your dog shivering in your whole life and watching him/her shivering after being spayed or being neutered, or any other procedure your dog endured, can make you worry. Actually, a dog shivering after surgery is quite common and an insight into what may be happening can help ease your mind, but before reading, grab a warm blanket or two for your dog to warm-up and don't hesitant to call your vet if something appears to be downright wrong!
A Matter of Slow Metabolism
When your dog is spayed or neutered, or undergoes any procedure that requires an anesthetic drug, he will be prone to some level of problem with his termoregulation system (the system that helps regulate your dog's temperature.)
During surgery and the administration of anesthetic drugs, dogs will undergo several procedures that potentially cause a lowered body temperature.
For instance, when intubated, the dog will breath in cold, dry air directly into the lungs, then some body parts are likely wet with surgical scrub solutions, body cavities may be open and the tables are cold, explains Christopher G. Byers, a board-certified veterinarian specializing in internal medicine.
Anesthetic drugs also tend to decrease the dog's metabolic rate by 15 to 40 percent. With a lower metabolic rate, the dog's hypothalamus (the dog's internal thermostat) is not able to work as efficiently as it should and this impacts the dog's body ability to generate heat. Basically, what happens is that the trigger to generate heat happens only until low temperatures are reached, further explains Dr. Byers.
"When you anesthetize a patient, one of the functions it loses is its ability to affect thermoregulatory control... They are also less metabolically active, so the body is burning less energy during anesthesia and that will decrease the amount of heat that is produced.”~Kelson Danielson, veterinary surgeon.
Veterinarians Take Precautions
Veterinarians are well aware of the problems associated with the onset of hypothermia (lowered body temperatures) while the dog is on the surgical table. For this reason, they are highly equipped to minimize the chances for hypothermia complications to set in.
Hypothermia while the dog is under anesthesia can cause lowered blood pressure, arrhythmia, lowered breathing rate, coagulation deficiencies and longer recovery times causing the affected dog to have a hard time metabolizing the anesthetics or waking up properly.
To prevent this from happening, veterinarians have special monitors hooked up to the dog to ensure that the dog's temperature and blood pressure stay at ideal levels. Veterinary staff are specially trained to monitor the dog's heart rate and rhythm, blood pressure, body temperature, oxygen levels and carbon dioxide output and promptly take action if there are any abnormalities.
At Tufts University, veterinarians blow warm air over their four-legged patients and use special blankets that recirculate warm water. The IV drip is used to keep dogs hydrated and thus, counteracting the decreased perfusion of blood, while the catheter comes handy to administer drugs quickly should the need arise. Minimizing the duration of the procedure as feasible can also help lower the chances for hypothermia to set in.
After surgery, dogs are still monitored before being sent home. Dogs have towels, blankets, or warming devices underneath them when they're in the recovery room and their body temperature is monitored every 15 minutes. Sometimes hot water bottles wrapped in blankets are placed for small patients.
Did you know? Young puppies have a harder time regulating their body temperature and therefore can get very chilled when they undergo anesthesia. A small puppy can be warmed up with a hair dryer set on low, blown over the hair while being extra careful moving it all the time, until the pup's temperature returns to normal, suggests veterinarian Dr. Gabby.
The Effect of Pain
A dog may therefore be shaking after surgery because he is cold, especially if he was discharged (sent home) shortly after; however, at times shaking, especially along with panting, could also be a sign of pain.
The onset of pain typically appears once the anesthetic starts wearing off. Many dogs are sent home with pain medications and they should be given as directed. Dogs often receive pain meds during surgery, so if the directions clearly say to give pain meds the day after surgery, avoid giving them earlier so to avoid dangerous overdosing Consult with your vet though if your dog seems in pain and you are unsure when you should give them.
And of course, if your dog seems in pain after surgery and you weren't sent home with pain meds, avoid giving any over-the-counter pain relievers which can be toxic and interact with any medications your dog was given.
"The side effects from anesthesia can certainly be lethargy and the dog could very well be painful. The shaking can just be the anesthesia and induction medications wearing off. Many dogs feel somewhat disorientated after surgery and if your dog was done fairly late in the day, the medications may not have completely worn off."~Dr. Scarlett
Did you know? When a dog undergoes a dental cleaning or extraction, the spraying of cold water into the mouth for an extended period of time may greatly reduce a dog's body temperature. The heat loss my be further exacerbated in older dogs because they tend to often lack muscle mass and fat, explains Jennifer Keef, a veterinary technician working in veterinary emergency and critical care. Not to mention the fact that dental procedures are often long, typically ranging from 45 minutes to 2 hours.
My Dogs Has Cold Paws After Surgery
Along with shaking, some dogs may have cold paws or cold ears after surgery. Not coincidentally, these are the areas that are more prone to getting frost bite, in a non-surgical scenario. The dog's paws are cold because dogs tend to lose heat through their foot pads, explains veterinarian Dr. John.
Generally, though if the dog is able to walk around without problems, it shouldn't be much of a concern, and on top of that, walking around can be helpful as helps in increasing perfusion.
With more blood flowing around, there are chances the dog's temperature may go up as well. However, again, should the dog have problems walking, he should be immediately seen, warns Dr. John.
A Thorough Check Up
A dog shaking after surgery is not unusual, but if you are concerned, it's a good idea to check your dog's vitals.
First, you can check how well your dog's perfusion is. Lift your dog's lips and check your dog's gums. They should be moist and of a nice bubble gum pink color, a sign that they are nicely vascularized, courtesy of oxygen-rich blood. If the gums are white or pale, the dog should be seen immediately as this can be a sign of internal bleeding.
Perfusion can also be checked by assessing your dog's capillary refill time. Gently press your finger on your dog's gum until it blanches, turning white. Then, release your finger, The gum should ideally return to a healthy pink in 1.5 seconds, but as long as it doesn't take no more than 2 seconds, it should still be fine, remarks veterinarian Ron Hines.
You may also want to take your dog's rectal temperature using a digital thermometer (the type that beeps). Normally, dogs have a temperature anywhere between 101 to 102.5 degrees Fahrenheit. If it seems low, like less than 100 degrees, call your veterinarian and report your reading along with a description of your dog's physical state. Call your vet also if the temperature is high (like 103 or over), in this case, your dog may be shivering due to a fever!
Help Your Dog Warm Up
If your dog is just shivering due to cold, and he doesn't have any rapid panting, increased respiratory rate, trouble breathing, pale gums, low or high temperatures, or other worrisome symptoms, you can try to help your dog feel better at home, but it's never a bad idea to give your vet's office a quick call just to make sure the shivering is nothing to worry about.
At home, you can try to cover your dog with some blankets and then record the rectal temperature after a while and see if it has gone up. While using a heat pad may be tempting, consider that there are reports of dogs getting burned this way. When a dog is drowsy after surgery, he may not move away if it gets too hot as he normally would or he might not perceive the heat too well, which makes the use a heat pad particularly risky.
Did you know? According to a study conducted by the Universidad CEU Cardenal Herrera and published in Veterinary Record , over 80 percent of dogs develop hypothermia after surgery with anesthetic!
How Long Will it Last?
According to research conducted by Daniel I. Sessler and published in the Journal of American Anesthesiologists, a return to normal temperature is expected when the concentration of anesthetic in the brain lowers enough to restore normal thermoregulatory defenses.
It may take anywhere between 2 to 5 hours to return to normal functioning; however, any residual anesthesia and opiods prescribed to control post-surgery pain, may cause delays. The age of the patient may also play a role. So play it safe and consult with your vet if you dog keeps trembling after surgery and his temperature doesn't give any signs of rising back to normal.
- Sessler DI. Perioperative heat balance. Anesthesiology 2000;92:578-596 Haskins S. Perioperative monitoring. In: Paddleford R, ed. Manual of small animal anesthesia. 2nd ed. Philadelphia, Pa: WB Saunders Co, 1999;123-146. Journal of the British Veterinary Association Retrospective study of the prevalence of postanaesthetic hypothermia in dogs J. I. Redondo, DVM et al,DVM260, Cold critters: Understanding hypothermia DVM360: Cold critters: Assessing, preventing, and treating hypothermia Tufts University: Pets and Anesthesia Veterinary Practice News: Correct Body Temp During Surgery Speeds Recovery