Learn about Electrolytes in Veterinary Care

Citrate Toxicity Calculator for Dogs

Those of you who have ever participated in canine blood donation might have encountered a situation when the blood flow through a sampling line has significantly slowed down or even completely stopped, and despite your best efforts, you had to abort the mission. As a result, the blood bag may end up being half full and contain only 200-250 ml of blood. Since the majority of commercially available donor bags contain 63-70 ml of citrate-based anticoagulant, they are designed to be filled up with 400-450 ml of donor blood to maintain a 1:7 – 1:9 citrate-to-blood ratio. If not, the citrate-to-blood ratio goes up, which creates a risk for citrate toxicity during a blood transfusion. In this situation, a clinician or technician may elect to waste this blood product and send this donor home since collecting another full bag of blood will not be safe for the donor animal. On the other hand, there is an extreme shortage of blood products in veterinary medicine, and, if possible, any waste should be avoided. In this blog post, I will give you a tool that may help you decide on whether a blood product with a high citrate-to-blood ratio should be discarded or safely given to a prospective recipient.

Approach to Hypernatremia in Dogs and Cats

Hypernatremia is defined as a serum sodium level above the reference range. It is a relatively infrequently encountered electrolyte disturbance in dogs and cats. In one retrospective study (Ueda et al. 2015), 5.7% dogs and 8.0% cats were diagnosed with hypernatremia. It was associated with increased case fatality rates in this population of patients. Understanding hypernatremia requires a comprehension of body fluid compartments, as well as concepts of the preservation of normal body water balance. The animal body maintains a normal osmolality between 280 and 310 mOsm/kg via Arginine Vasopressin (AVP), thirst, and the renal response to AVP; dysfunction of all three of these factors can cause hypernatremia (Mushin et al. 2016). In this post, I present a step-by-step approach to the hypernatremia in canine and feline patients. Further reading is recommended to deepen understanding of the physiology and pathophysiology of sodium and water balance.

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Approach to Hypokalemia: Diagnosis and Treatment

All causes of hypokalemia can be divided into 3 big groups:

Decreased intake (unlikely to be a sole cause)
Intracellular shift
External loss (GI or renal)

A step-by-step approach to diagnosis of hypokalemia

Step 1: Review current medication history. Drugs that can promote hypokalemia (via intracellular shifting or increased losses/decreased intake):

K-deficient fluids
loop/thiazide diuretics
insulin, dextrose
albuterol, terbutaline and other beta agonists
catecholamines

Approach to Hyperkalemia: Diagnosis and Treatment

This blog post commences a series of articles on diagnostic and therapeutic approaches to potassium and sodium derangements. This is meant to be a quick reference/guideline for emergency veterinarians, students and technicians. All readers are welcome to leave feedback and comments below.

Wide complex tachycardia – More complex than first thought?

A 7 year-old male neutered domestic shorthaired 5 kg cat is currently hospitalized for management of an aortic thromboembolism. The cat was diagnosed with hypertrophic cardiomyopathy, left sided congestive heart failure and aortic thromboembolism causing complete lack of motor function in the pelvic limbs. It is being managed with oxygen therapy provided by commercial oxygen kennel, 2 μg/kg/hr fentanyl infusion, furosemide 2 mg/kg q12 hours and 18.75 mg clopidogrel. The cat is being monitored with regular respiratory rate checks and continuous electrocardiogram (ECG). The cat began to show some improvement in pelvic limb motor function. However, 48 hours post initiation of therapy there was a dramatic change in the ECG (Figure 1).