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Diabetic ketoacidosis
Dr. Salam Fareed
INTRODUCTION
Diabetic ketoacidosis (DKA) is an acute, major, life-threatening complication of diabetes that
mainly occurs in patients with type 1 diabetes, but it is not uncommon in some patients with
type 2 diabetes.
This condition is a complex disordered metabolic
state characterized by:
➢ hyperglycemia: blood glucose level > 200 mg/ dl
➢ Ketoacidosis: ketonuria > ++ on standard urine sample.
➢ Metabolic acidosis: PH < 7.3, s. bicarbonate < 15
Pathophysiology
DKA typically occurs in the setting of hyperglycemia with relative or absolute insulin
deficiency and an increase in counterregulatory hormones.
Sufficient amounts of insulin are not present to suppress lipolysis and oxidation of free
fatty acids, which results in ketone body production and subsequent metabolic acidosis.
DKA occurs more frequently with type 1 diabetes, although 10% to 30% of cases occur in
patients with type 2 diabetes.
Predisposing Factors
Several risk factors can precipitate the development of extreme hyperglycemia:
1. infection.
2. intentional or inadvertent insulin therapy.
3. myocardial infarction.
4. Stress.
5. trauma.
6. confounding medications, such as glucocorticoids or atypical antipsychotic agents.
Clinical Presentation
The most common early symptoms of DKA are the insidious increase in polydipsia and
polyuria. The following are other signs and symptoms of DKA:
1. Malaise, generalized weakness, and fatigability
2. Nausea and vomiting; may be associated with diffuse abdominal pain, decreased
appetite, and anorexia
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3. Rapid weight loss in patients newly diagnosed with type 1 diabetes
4. History of failure to comply with insulin therapy or missed insulin injections due to
vomiting or psychological reasons or history of mechanical failure of insulin infusion
pump
5. Decreased perspiration
6. Altered consciousness (eg, mild disorientation, confusion)
Signs and symptoms of DKA associated with possible intercurrent infection are as follows:
1. Fever
2. Coughing
3. Chills
4. Chest pain
5. Dyspnea
6. Arthralgia
7. Urinary symptoms
On examination
1. Ill appearance
2. Dry skin
3. Labored respiration
4. Dry mucous membranes
5. Decreased skin turgor
6. Decreased reflexes
7. Characteristic acetone (ketotic) breath odor
8. Tachycardia
9. Hypotension
10. Tachypnea
Investigations:
1. Serum glucose levels
2. Serum electrolyte levels
3. Amylase and lipase levels
4. Urine dipstick
5. Ketone levels
6. ABG measurements
7. CBC count
8. BUN and creatinine levels
9. C-RP
10. Urine and blood cultures if intercurrent infection is suspected
11. ECG
12. Chest radiography: to rule out pulmonary infection
13. Head CT scanning: to detect early cerebral edema.
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Management:
Managing diabetic ketoacidosis (DKA) in an intensive care unit during the first 24-48 hours
always is advisable.
Plan for therapy:
When treating patients with DKA, the following points must be considered and closely
monitored:
1. Correction of fluid loss with intravenous fluids
2. Correction of hyperglycemia with insulin
3. Correction of electrolyte disturbances, particularly potassium loss
4. Correction of acid-base balance
5. Treatment of concurrent infection, if present
Laboratory studies for diabetic ketoacidosis (DKA) should be scheduled as follows:
1. Blood tests for glucose every 1-2 h until patient is stable, then every 4-6 h
2. Serum electrolyte determinations every 1-2 h until patient is stable, then every 4-6 h
3. Initial blood urea
4. Initial arterial blood gas (ABG) measurements, followed with bicarbonate as necessary
Example how to arrange a chart to follow a DKA patient
Insulin Therapy:
Using soluble (Short acting) insulin administered either:
➢ I.V infusion(prefered method):
o Bolus: 0.1 unit/ kg. I.V direct
o then maintain contiueous iv infusion of 0.1 unit/ kg./ hr. using syringe pump.
➢ I.M:
o Bolus: 10-20 units
o Followed by 5 units hourly.
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Target blood sugar:
Falling 55-110 mg/ dl per hr.
(3-6 mmol/l)
• Rapid decline → cerebral edema
• Failure to reach the target → require reassessment of insulin therapy.
Shift to subcutaneous insulin regimen when the patient vomiting stopped and become
biochemically stable.
Fluid Replacement:
Average of 6 litres fluid deficit exist
➢ 3 L are extracellular replaced by 0.9% isotonic saline.
➢ 3 L are intracellular replaced by dextrose
Set 2 wide bore IV line initially
Timing and amount as following:
1
st
hr: using normal (isotonic) saline
✓ systolic BP > 90 mmHg → 1 L
✓ systolic BP < 90 mmHg → 2 L
Then as :
✓ 1 L OVER 2 hrs
✓ 1 L OVER 2 hrs
✓ 1 L EVERY 6 hrs
Shift to 10% dextrose fluid whenever blood sugar level become < 250 mg/dl (14mmol/l).
Note: be cautious with elderly, pregnant, those with heart or renal failure.
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Potassium Replacememt
According to serum potassium level as:
✓ > 5.5 mmol/l → non to be given
✓ 3.5 – 5.5 (mmol/l) → 40 meq/l
be cautious in replacing K usually hyperkalemia occurs initially due to prerenal failure
secondary to dehydration for that reason K is not recommended to be given in the first hour
of therapy.
Other
✓ Acidosis: is usually corrected with the time by adequate fluid and insulin
replacement. Bicarbonate therapy is not recommended as it can induce cerebral
edema
✓ Infection: should be treated by antibiotcs accordingly
✓ Brain edema: is the leading cause of death in DKA, it can exist in spite of metabolic
stablisation. It should be treated by mannitol solution 20% (7 ml/ kg.)
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Case Scenario
A 20-year-old woman is evaluated in the emergency department for polyuria, polydipsia,
polyphagia, and an unintentional 5.4-kg (11.9-lb) weight loss over the past month. She has
had increasing lethargy over the last 24 hours. Her medical history and family history are
unremarkable. She takes no medications.
On physical examination,
temperature is 37.5 °C , blood pressure is 98/52 mm Hg, pulse rate is 120/min, and
respiration rate is 30/min. BMI is 17.
She is lethargic with dry mucous membranes, tachypnea, and tachycardia. Chest
auscultation is clear. Abdominal examination shows diffuse mild tenderness and normal
bowel sounds. There is no rebound tenderness or guarding with palpation.
Laboratory studies:
1. Hemoglobin= 17 g/dL (170 g/L)
2. Leukocyte count= 14,200/µL (14.2 × 10
9
/L)
3. Blood gases, arterial::
• pH= 7.25
• PCO
2
= 21 mm Hg
4. Creatinine= 1.3 mg/dL
5. Electrolytes
• Sodium= 130 mEq/L
• Potassium= 3.0 mEq/L
• Chloride= 99 mEq/L
• Bicarbonate= 9 mEq/L
6. Glucose= 620 mg/dL (34.4 mmol/L)
7. An electrocardiogram shows sinus tachycardia 120/min.
8. Chest radiograph is normal.
What is the most appropriate management?