DKA

Question 1

definition

Answer 1

state of hyperglycemia (>11 or 14 in severe cases), ketosis with acetone in urine and b-hydroxybutyric acid in serum, and wide anion gap metabolic acidosis (pH <7.3 and bicarb <18 with low pCO2 as compensation)

Question 2

etiology

Answer 2

commonly in type 1 diabetes
1. undiagnosed
2. poor adherence to insulin therapy
3. increase insulin demand in cases of stress (infection, trauma, burns, surgery)

Question 3

pathophysiology

Answer 3

1. osmotic diuresis and hypovolemia
   insulin deficiency -> hyperglycemia -> hyperosmolarity -> osmotic diuresis and loss of electrolytes -> hypovolemia (AKI?)
2. high anion gap metabolic acidosis
   insulin deficiency -> lipolysis -> high free fatty acids converted to ketones (acidic) -> bicarbonate consumption as buffer (alkaline) -> high anion gap met acid with resp compensation
3. intracellular potassium deficit
   insulin deficiency -> hyperosmolality -> K+ shifts to extracellular space -> lack of insulin to promote cellular uptake of K+ -> total body K+ deficit despite NORMAL OR HIGH serum K+ levels

Question 4

clinical features

Answer 4

RAPID onset (<24hrs)
polyuria, polydipsia, recent weight loss
N&V (expel gastric acid to shift acid-base balance of the body)
signs of dehydration
neurological: lethargy, coma

diffuse abdominal pain (ketoacidosis irritates peritoneum)
fruity odor on breath
hyperventilation (kussmaul respirations) to compensate acidic state

Question 5

diagnosis

Answer 5

RBS: more than 11
BMP: bicarbonate <18, high anion gap >10, high BUN and creatinine indicating dehydration

urine dipstick for ketones and glucose, serum for hydroxybutyrate

blood gas analysis for pH <7.3

hyponatremia, hypomagnesemia, potassium normal or high

rule out other causes: acute abdomen, pregnancy test, sepsis CBC, MI do ECG

Question 6

treatment

Answer 6

CONTINUOUS monitoring of electrolytes, glucose, bicarb, pH, etc

1. fluid replacement (MOST IMP)
   with 0.9% NaCl
   1L in first hour then 250-500ml every hr
2. insulin therapy
   0.1 unit/kg/hr
3. potassium therapy
   >5.5 no need
   <5.5 add KCL (4mmol/L KCL to every L of NS)
   if <3 hold insulin until you replace K+
4. if pH <7 add 500 ml NaHCO3

once the patient can eat and drink normally, subcutaneous basal insulin with food is started and overlapped with iv insulin for 30 minutes then weaned off IV

Question 7

when is DKA resolution?

Answer 7

if glucose <11 PLUS 2:
pH > 7.3
anion gap <12
bicarb >15