Diabetic Ketoacidosis (DKA)
Jaime Moo-Young, MD
Pathogenesis
 Insufficient insulin for a given carbohydrate load decreased cellular metabolism of glucose
 Increased gluconeogenesis, glycogenolysisHyperglycemia
 Increased breakdown of free fatty acids as alternative energy source ketone and ketoacid
accumulation
 Hyperglycemiaserum hyperosmolality osmotic diuresis dehydration and electrolyte
derangements (dehydration is most lethal!)
 Seen almost exclusively in Type I diabetes; rarely in Type II
Definition: Triad of
1. Hyperglycemia (usually between 500 – 800 mg/dL or 27.8-44.4 mmol/L)
2. Anion Gap Metabolic Acidosis (pH usually <7.30)
3. Ketonemia: -hydroxybutyrate, acetoacetate most significant
** Urine ketones do not make the diagnosis, but they can support it**
Triggers (the “I’s”): Don’t forget to ask about these!
 Insulin deficiency: insulin non-compliance, insufficient insulin dosing, new-onset Type I diabetes
 Iatrognic: glucocorticoids, atypical antipsychotics, high-dose thiazide diuretics
 Infection: UTI, pneumonia, TB
 Inflammation: pancreatitis, cholecystitis
 Ischemia/infarction: MI, stroke, gut ischemia
 Intoxication: Alcohol, cocaine, other drugs
Presentation
 Symptoms
o Polyuria, polydipsia, weight loss
o Nausea, vomiting, abdominal pain
o Fatigue, malaise
o Associated trigger sx (fever/chills, chest pain, etc)
 Signs
o Volume depletion:  skin turgor, dry axillae, dry mucus membranes, HR,  BP
o Altered mental status: stupor, coma
o Kussmaul respirations: rapid, shallow breathing = hyperventilation to counteract
metabolic acidosis
o Fruity, acetone odor on breath
Lab workup and findings
 Hyperglycemia: > 250 mg/dL in serum, + glucose on urinalysis
 Acidemia (pH <7.30 on ABG)
 Ketosis: positive -hydroxybutyrate in serum, positive ketones on urinalysis
 Anion gap >12: Anion gap = [Na] – [Cl] – [bicarbonate]
 Hyperosmolality >290 mOsm/L : 2 Na + 2 K + BUN/3 + glucose/18
 Pseudohyponatremia: Measured sodium is low due to osmotic movement of free water into
bloodstream resulting from hyperglycemia. Total body sodium usually is normal.
Corrected Na = measured Na + [2.4 x (serum glucose -100)/100]


Hyper or hypokalemia
o Total body K is low due to increased urinary losses.
o Measured K may appear high due to
 Increased entry out of cells in exchange for H+ ion during acidosis
 Insulin deficiency (insulin normally allows K entry into cells)
o VERY important to replete K as you treat DKA, since insulin administration will cause K
levels to drop as it enters cells.
BUN and creatinine: may be increased secondary to dehydration (prerenal azotemia)

May have elevated WBC and amylase, even if no pancreatitis
Management
1. Assess ABC’s
2. Assess mental status: may need intubation if GCS<8
3. Assess volume status: hang IV fluids immediately
4. Take focused history, with special attention to precipitating factors (infection, MI, etc)
5. Physical exam, with attention to possible precipitant (fever, rales, chest pain, etc)
6. Lab evaluation:
a. Serum glucose: Measure every hour until <250-300
b. Serum electrolytes with calculation of anion gap: Measure on presentation and ideally
every 2-4 hours
c. Urinalysis (check for ketones, glucose)
d. CBC
e. Serum ketones
f. ABG if serum bicarbonate is < 18
g. Additional tests based on suspected precipitant (CXR, cardiac enzymes, LFTs, urine tox
screen, etc)
7. Aggressive Hydration: at least 10-15 mL/kg/hour of NL saline
8. Insulin administration (Regular = formulation of choice):
a. 10 units IV push, followed by 0.1 unit/kg/hour (can calculate this for IV boluses)
b. Continue insulin drip or equivalent until anion gap is <12
c. If glucose <250 and anion gap is still >12, add D5 to IV fluids and continue insulin hourly
until anion gap <12
d. Once anion gap has closed and pt is able to eat, start subcutaneous insulin dose.
 Resume home insulin dose if previously effective
 If new-onset Type I DM, insulin estimate = 0.5 units/kg/day, divided into long-acting
and prandial insulin
**Overlap insulin drip/hourly IV glucose and SQ insulin by 3 hours, or else anion
gap can open up again**
9. Replete electrolytes
a. K+: Add 20-40 mEq per L of IV fluids if serum K <4.5
b. Na: usually will increase to normal as hyperglycemia is corrected
c. Bicarbonate: only give if pH <6.9
d. Phosphate: replete if <1.0
10. Address precipitating factor: treat infection, d/c offending meds, counteract drug ingestion, etc.
Sample DKA Flow Sheet:
Time
Vital signs
Glucose
Anion Gap
K+
IV fluids given
0600
0700
90/60, 125
550
480
18
3.5
2 L NS w/ 40 mEq K
1 L NS w/ 20 mEq K
121/70, 90
Insulin
Given
10 U IV
7 U IV
Pitfalls to Avoid
 Do not stop IV insulin before starting subQ insulin 2-3 hours beforehand; otherwise, anion gap
may open up due to failure of ketone clearance.
 Do not cause cerebral edema by rehydrating too rapidly. Guideline = 10-15 mL/kg/hr, unless pt is
in shock
 Do not lower glucose level too quickly; if drops <200 within 1st 5 hrs of treatment, can cause
rebound ketosis.
 Do not cause hypoglycemia by failing to add dextrose to IV fluids once glucose <250 mg/dL, and
insulin drip is continued because anion gap >12
 Do not mistakenly attribute another cause of anion gap metabolic acidosis to DKA
References:
1. www.uptodate.com
2. www.emedicine.com
3. Sabatine et al. Pocket Medicine, Fourth Edition. Wolters Kluwer, Lippincott Williams & Wilkins, 2010.
4. Longmore et al. Oxford Handbook of Clinical Medicine, Eighth Edition. Oxford University Press, 2010