Excess Alkali in the Blood in Dogs

Imbalance in the acid-base level in the blood is a serious condition. The normal blood PH for dogs and other small animals is just above 7. Individual levels may vary somewhat, but a PH that is too high indicates that alkali or base compounds in the blood are out of balance. This is called metabolic alkalosis; it is the reverse of metabolic acidosis, in which the blood becomes too acidic. Acidosis is more common, but alkalosis can also be a problem. The most common cause of alkalosis is excessive vomiting of gastrointestinal enzymes which leads to below normal levels of hydrochloric acid. Dehydration often occurs in combination or as a result of alkalosis. The vomiting can be the result of a number of underlying causes including infection, obstruction of the upper gastrointestinal tract, and poisoning. Overuse of certain drugs can also result in excess alkali. The underlying condition that is causing the problem will need to be treated to rectify the imbalance.

Excessive alkali in the blood in dogs leads to a higher than normal PH level on a blood test. Veterinarians define this as metabolic alkalosis. In dogs, it is usually the result of excessive vomiting, but occasionally there may be other more complex reasons.

Symptoms can vary depending on the cause of excess alkalosis. The most common associated conditions are vomiting and dehydration. As the imbalance increases however, symptoms may be directly connected to the excess alkali. Take your dog to see a veterinarian if you notice any of the following signs:

• Vomiting
• Dehydration
• Headache
• Lethargy
• Weakness
• Tremors
• Seizures
• Arrhythmia

Types 

There are several different types of alkalosis.

• Hypochloremic metabolic alkalosis – the most common type, occurs through loss of hydrochloric acid
• Metabolic alkalosis from increased bicarbonate (HCO3-) – this is rare and often occurs as the unintended result of another medical treatment
• Respiratory alkalosis – also known as hyperventilation, this is the reverse of respiratory acidosis in which too much carbon dioxide builds up in the blood. It can be a compensation for metabolic acidosis (such as heavy panting which occurs with shock)

These are some of the most common issues associated with metabolic alkalosis:

• Sustained vomiting
• Excessive use of diuretics or corticosteroids
• Medical treatment of acidosis (adding bicarbonate)
• Cushing’s disease
• Kidney failure
• Dehydration
• Poisoning
• Foreign body obstructing the upper gastrointestinal tract
• Tumor

Continual vomiting is the most obvious and straight-forward cause of excess alkali, so it is the most commonly associated symptom. A blood test can usually confirm the diagnosis.  In more complex cases, the veterinarian will likely analyze blood gas levels and measure the anion gap also. The body compensates as much as possible to stabilize acid and base levels, so a complete chemical analysis may be necessary to trace the root of the problem.

The veterinarian will want to know your dog’s complete medical history. Since alkali can often be the result of over-medication, any past or current prescriptions will be relevant. A detailed description of your dog’s symptoms is also helpful, including signs of chest pain or difficulties swallowing. Depending on the cause, X-rays or further testing may be necessary.

Many conditions of excessive alkali can be reversed with a saline solution administered through an IV. This will reduce dehydration and bring blood levels back to a normal. Hypokalemia (potassium deficiency) is often present with alkalosis, so this will be treated at the same time. Most types of alkalosis related to excessive vomiting respond to this type of treatment.

When the immediate symptoms are reduced, the veterinarian will treat the underlying cause. This could involve surgery if the vomiting is due to a foreign body, tumor or other blockage. The risk involved with the surgery will depend on the problem, but there will need to be follow-up appointments with this treatment, as well as a two to three week recovery period. 

Infections that cause excessive vomiting many need to be treated with an antibiotic or other medication.

More complex sources of metabolic alkalosis are less likely to respond to simple re-hydration. Kidney failure may indicate the need for dialysis. Cushing’s disease that is causing alkalosis will also require medical treatment.

Treatment could involve changing or reducing your dog’s other medications. Overuse of diuretics or corticosteroids is another cause of metabolic alkalosis.

The most straightforward cases of excess alkali are treatable and your dog will make a full recovery. More complex issues could require long term management including medication or dialysis appointments. The balance between acid and base elements in the blood is delicate and complex. There could be an easily treatable reason for your dog’s condition, or it could be the result of a complex reaction to another problem. It will depend on your dog’s specific symptoms and the diagnosis of a veterinarian.