A dog gasping for air before dying can be an image dog owners may have a hard time getting out of their head, but in most cases, the gasping is not indicative of trouble breathing. As dogs die, a variety of changes take place and these changes involve the way oxygen is managed during those last minutes on earth. Affected dogs may be opening and closing their mouths, there may be seconds or minutes of open-mouth breathing, and the dogs may appear as if gasping for air. Turns out, a dog gasping for air before dying is a natural process and has little to do with a dog struggling to breathe.
Breathing Changes Before a Dog Dies
As a dog approaches death, it's not uncommon to witness changes in the way the dog breathes. Affected dogs may go through cycles of breathing changes, and sometimes during these cycles, the breathing may stop, only to shortly start once again. The breathing that follows this pause is often quite deep and rapid. Then, the breathing gets shallower and shallower until it completely stops.
This type of breathing in human hospice is referred to as Cheyne-Stokes breathing. It's named after Dr. John Cheyne and Dr William Stokes who first described this typical breathing pattern in the 19th century.
On top of these breathing changes, because swallowing becomes more difficult when death approaches, secretions that would otherwise be swallowed or coughed up may pool at the back of the dog's throat. This happens because the salivary glands still work although the digestive system has shut down.
These accumulated fluids may cause air bubbles and guttural noises in people and dogs (often referred to as death rattle), however, they are not as common in dogs as it happens in humans. Positioning the dog with the head to the side on top of some towels may help drain and absorb some excess fluids.
And then, gasping may take place just prior to death whether the death was induced by euthanasia injection or the death occurred naturally. These gasps or episodes of open-mouth breathing may appear to the dog owner as if the dog is struggling to breath and therefore may be perceived as traumatic to witness.
"At the moment of death, there is often spasmodic or gasping breathing. The pupils may dilate and the animal may stretch out or perhaps pass urine. The final dying process lasts usually lasts for about a minute or less."~Dr. Richard Pitcairn
A Case of Agonal Breathing
A dog gasping for air before dying is likely experiencing what is known as "agonal breathing" also sometimes referred to as "autoresuscitation."
Although the gasps may appear as if the dog is breathing or struggling to breathe, just like a fish out of water, what is really happening is that the dog is actually not really breathing. These breaths are not bringing oxygen to the body as normal life-sustaining breathing does. So what's their purpose then?
Agonal breathing is the body's natural attempt to bring oxygen to the organs, and although it's not effective, it's a natural, reflexive and primitive phenomenon developing from the ventilatory center located in the brain stem. It's the result of a sudden spasm of the diaphragm and the muscles in the jaw.
Its primary function is to sort of "jump start" the body. It's basically the brain's last attempt to try to "save" the dog's life although fruitless. What happens is that, once the dog's heart stops pumping, the brain fails to get the vital oxygen it needs. It therefore turns on a reflexive type of breathing which leads to these final gasps. "Our heart, lungs and brain stem are essential to our survival, so the last ditch-effort for survival takes place in the chest and brain," explains Ginger Alvarez in the book "The Hospice Walk."
Gasping is therefore a well-studied physiological event that takes place during death. With the body deprived from oxygen, there is an initial period of arousal with increased depth and rate of breathing, followed then by temporary apnea (temporary cessation of breathing) lasting seconds or minutes and then the gasping stage. The gasps then become gradually weaker and weaker ending in terminal apnea with complete cessation of breathing movements.
Did you know? In human hospice care, agonal breathing may often prompt family members to call nurses and doctors to perform CPR, but hospital staff will discourage this as they know for a fact that doing so would be useless at this point and they suggest the family focusing on holding the dying person's hand while talking to their loved one.
"There are cases where once the euthanasia solution begins relaxing the entire body, the body attempts to continue doing the things it's made to do which are breathe and continue burning energy. This shows up as muscle twitching or movement, gasping and sometimes vocalizing."~Dr. Taylor, veterinarian
Dog Gasping For Air Before Dying
As distressing as witnessing a dog gasping for air before dying may be, the good news is that most agonal breathing takes place once the dog is unconscious. The eyes may be open, there may be a gasping sound and the body may jerk, but the dog is most likely unaware of all of this occurring.
Dogs who are gasping are profoundly affected by oxygen deprivation which renders them unconscious. With the present knowledge about brain function, pain and suffering of nowadays, it is therefore safe to conclude that dogs who are gasping are very probably not in pain nor are suffering.
Why do some dogs develop agonal breathing and others do not? There is no certainty as to why, but there are chances that dogs suffering from some sort of circulatory problem or heart problem (which is very common with very old or very sick animals) may be more predisposed.
Interestingly, gasping is nearly a universal phenomenon that is present at the beginning of life and right at the end of it. At birth, the gasping follows the apnea to allow the lung's first intake of air, while at death, the gasping takes place right before the apnea so to allow the lung's final outtake of air.
" In some individuals a terminal gasp may occur when the animal is unconscious and although this may distress some observers, it is not an expression of pain or discomfort, merely a reflex action."~World Society for the Protection of Animals
- BMC Cardiovasc Disord. 2010; 10: 36. Continued breathing followed by gasping or apnea in a swine model of ventricular fibrillation cardiac arrest Mathias Zuercher et al.
- World Society for the Protection of Animals: Methods for the euthanasia of dogs and cats
- The Hospice Walk: By Ginger Alvarez