Ketoacidosis

From Dog

Diabetic ketoacidosis (DKA) is a serious medical complication of canine diabetes mellitus characterized by hyperglycemia, metabolic acidosis (venous pH < 7.35)[1] and ketosis (BOHB concentration >2.0 mmol/L)[2].

Diabetic ketoacidosis is a serious consequence of diabetes, sometimes exacerbated by use of oral biguanide agents such as metformin.

Ketoacidosis is a consequence of diabetes mellitus and commonly triggered by a precipitating event such as a urinary tract infection, pancreatitis, pyelonephritis, cholangiohepatitis, irritable bowel disease, prostatitis, pyometra, upper respiratory tract infection or pneumonia[3].

DKA is the culmination of diabetes mellitus where excessive amounts of ketones (acetoacetic acid, β-hydroxybutyrate and acetone) form in the liver resulting in metabolic acidosis (due to lactic acid formation), severe dehydration, shock and often, death. Diuresis as a result of diabetes also causes loss of sodium and potassium through the kidneys, exacerbating hypovolaemia and dehydration. Stress hormones such as cortisol and epinephrine exacerbate the hyperglycaemia, resulting in a vicious cycle. Eventually, hyperviscosity, thromboembolism and severe metabolic acidosis cause renal failure and death.

Therapy includes:

  • correcting dehydration by administration of IV fluids, (such as 0.45% NaCl + 2.5% dextrose, or lactated Ringer’s solution). Any commercially available isotonic crystalloid solution may be used. The use of 0.9% saline has been advocated because of its relatively high sodium concentration, however its administration may be contraindicated in hyperosmolar diabetics in whom serum sodium concentrations initially is high. LRS, which contains lactate and acetate that is converted to bicarbonate in the blood, assists in alkalinising the blood and thus correcting acidosis associated with DKA.
  • reducing hyperglycemia and ketosis by administration of crystalline zinc (regular) insulin
  • maintaining serum electrolyte levels, especially potassium, through supplemental administration of appropriate electrolyte solutions
  • identifying and treating underlying and complicating diseases, such as acute pancreatitis or infections.

References

  1. O'Neill S et al (2012) Evaluation of cytokines and hormones in dogs before and after treatment of diabetic ketoacidosis and in uncomplicated diabetes mellitus. Vet Immunol Immunopathol 148(3-4):276-283
  2. Sears KW et al (2012) Use of lispro insulin for treatment of diabetic ketoacidosis in dogs. J Vet Emerg Crit Care (San Antonio) 22(2):211-218
  3. Greco, DS (2009) Complicated diabetes mellitus. In Bonagura, JD & Twedt, DC (Eds): Kirk's current veterinary therapy XIV. Saunders Elsevier, St Louis. pp:214