DKA Flashcards
DKA definition
n Life threatening complication of uncontrolled
diabetes mellitus
n Sequela of insulin deficiency
Hallmark diagnosis of DKA
- Hyperglycemia
- Glucosuria
- Ketonuria
- +/- Metabolic acidosis
4 conditions ass’d with ketone production:
- Insulin deficiency
- Starvation
- Dehydration
- Diabetogenic Hormone Excess
n Glucagon, Epinephrine, Norepinephrine, Cortisol, Growth Hormone
Diabetic Ketoacidosis - what is it? which ketones are present?
n Cellular starvation in the face of hyperglycemia
n Ketones - alternate energy source
1. Acetone
2. Acetoacetate
3. ß-hydroxybutyrate
what are ketones? what conditions / clinical signs do they contribute to?
Organic acids
n Alternate energy source
> Short term
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Contribute to:
n Acidosis
n Nausea
n Feeling terrible
n Diuresis
n Dehydration
DKA Patients usually fall into what categories?
n Newly diagnosed diabetics
n Known diabetics with an often precipitating underlying cause
DKA Patients can sometimes be known diabetics with an often precipitating underlying cause
- what are precipitating underlying causes for dogs?
n Urinary tract infection
n New endocrinopathy
n Acute pancreatitis
DKA Patients can sometimes be known diabetics with an often precipitating underlying cause
- what are precipitating underlying causes for cats?
n Acute pancreatitis
n Hepatic lipidosis
n Chronic inflammatory disease
n Bacterial or viral infections
n Chronic kidney disease
n Neoplasia
Non-specific changes we may see in a DKA patient on general PE
n Dehydration
n Weakness
n Tachypnea
n Kussmaul breathing
> Slow deep breathing due to severe metabolic acidosis
n Acetone breath
n Abdominal pain
n Hepatomegaly
n Muscle wasting
DKA diagnostics - CBC results for dogs and cats
~ 50% of dogs with DKA have:
n Non regenerative anemia
n Neutrophilia with left shift
n Thrombocytosis
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Cats with DKA have»_space;
n Heinz bodies
n Correlated with plasma β-Hydroxybutyrate
DKA diagnostics - what do we see on biochem?
Typical findings:
- increased glucose (persistent/repeatable)
- decreased tCO2 (reflective of a low bicarbonate)
- increased Urea / creatinine
- increased (mild) ALT, ALP, AST
- increased Amylase & lipase
DKA diagnostics - urinalysis results
Urinalysis or Urine Dip Stick
n Glucosuria
n Ketonuria
n Bacteuria
how can we detect ketonemia / ketonuria? what exactly do they tell us?
n Urine reagent strips n Urine or Serum
n Detect acetoacetic acid & acetone
n Do NOT detect ß-hydroxybutyrate
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Acetoacetic acid can change into acetone or ß-hydroxybutyrate
> ß-hydroxybutyrate can change back to acetoacetic acid
β-hydroxybutyrate βHB normal vs DKA results in cats
n Normal: <0.5 mmol/L
n Ill / Diabetic cats: 0.5-2.0
n Diagnostic for DKA: > 2.55
β-hydroxybutyrate βHB normal vs DKA results in dogs
- Normal: < 0.15 mmol/L
- Diabetic: < 2.8
- DKA: ≥ 3.5
DKA urine culture - when to do it? results?
n Bacterial culture of urine should be performed regardless of sediment
n Urinary tract infection ~ 20% of dogs
> Cause: Diabetic immunosuppression
Most DKA patients show what clinical signs:
n Dehydrated
n Anorexic
n Metabolically deranged
> Electrolyte Disturbances
> Acid Base Disturbances
n Require hospitalization
Emergency Approach to DKA patient - what 5 things do they need, broadly?
- Rehydration
- Initiating Insulin
- Preventing & Correcting Electrolyte Disturbances
- Managing clinical signs
- Identifying & treating precipitating factors
rehydration for DKA patient
- how important? purpose?
n KEY
n Restores circulating blood volume & tissue
perfusion
n Clears ketones
n Corrects electrolyte disturbances
rehydration for DKA patient
- what fluids to use?
- how fast should deficits be corrected?
- what are losses? how do we deal with them?
- how much?
- how do we approach maintenance? when to start?
n Intravenous isotonic crystalloid solution
> Plasmalyte A, Normosol R, Lactated Ringers
> 0.9% NaCl (will exacerbate acidosis)
n Fluid deficits should be corrected within 24 hours
n Ongoing fluid losses can be large
> Frequent reassessment
> Ensure rehydration is moving according to plan
- 2x maintenance IV fluids is rarely enough!
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Maintenance Fluids
n 0.45% NaCl ideal
> Because diabetes mellitus patients have hypotonic water losses
n To start only once patient rehydrated & Na+ is within normal limits
insulin therapy for DKA
- When to initiate?
- purpose?
n Deliver IV fluids for at least 1-2 hrs before initiating insulin
n Insulin:
n Drives glucose into the cells
n Cellular starvation reversed
> Ketone production abolished
> Insulin also promotes ketone metabolism
WANT TO KEEP GIVING INSULIN
GOAL - Timely resolution of ketonemia
insulin therapy for DKA - what are our blood glucose goals for ongoing therapy? how much insulin?
n ONGOING Insulin therapy
n Reduce & maintain blood glucose (BG)
> BG - 5.5 - 14 mmol/L (100 to 250 g/dL)
n Add DEXTROSE (2.5-5%) to the IV fluids to allow continued insulin administration without causing hypoglycemia
n Maximizing insulin administration
which insulin to use for DKA therapy? protocols for admin? duration of action?
SHORT ACTING REGULAR INSULIN
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Regular (Toronto) Insulin
n Most widely used insulin
n Protocols
> IM / SC administration
> Intravenous Sliding Scale Infusion
n Duration of action of regular insulin
> IM 2-4 hours
> SC 4-6 hours
> IV administration - minutes to initiate / terminate effect Short acting
Regular Insulin
Routes of Administration – pros and cons
IM
n Pros: less equipment required
n Cons: repeated IM injections
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SQ
n Pros: less painful then IM
n Cons: repeat injections, potential for delayed uptake
> Not appropriate in dehydrated patient
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IV
n Pros: More precise
n Cons: More technically demanding
> At least 2 IV infusions (patient fluids & insulin infusion)
