Diabetic ketoacidosis (DKA)

 

D          (dextrose) Hyperglycemia            (glu>250) - lytes

K          Ketonemia                                 u/a

A          metabolic acidosis                      abg

electrolyte depletion

 

CAUSES

Insulin dependent diabetes mellitus (20-30% in newly diagnosed diabetics)

Infarction (myocardial) 5-7%

Infection (30-40%) usually respiratory or urinary

Idiopathic (20-30%)

Medication non-compliance

CVA

Trauma

Surgery

Emotional stress

 

LABORATORY

LYTES   Blood sugar elevated (usually 250-800 mg/dL [13.88-44.4 mmol/L] range)

Increased ANION GAP Na-(Cl+HCO3)>14 : Serum ketosis

Hyponatremia

Increased BUN

HCO3 < 15 (< 15 mmol/L)

Decreased calculated total body K+

U/A       Urine ketosis

Glycosuria

WBC / Bacteria - infection

ABG      Metabolic acidosis

Hyperamylasemia

Hypertriglyceridemia

Hypercholesterolemia

Increased serum osmolality

LFTs     eval abd pain

 

Disorders that may alter lab results:

With concomitant lactic acidosis, acetoacetate production may be inhibited in presence of high levels of beta hydroxybutyrate. The nitroprusside reaction, which measures only acetoacetate, may not be strongly positive.

A very low serum sodium (< 110 mmol/L) suggests an artifact due to severe hypertriglyceridemia

Severe acidosis gives artificially high K+ level

Markedly increased serum ketones may cross react and cause a falsely high serum creatinine

CBC - leukocytosis

 

SPECIAL TESTS

ECG (especially if MI suspected). May also assist in evaluation of K+ status. Usually shows sinus tachycardia.

Urine and blood cultures

 

IMAGING

Chest x-ray to rule out pulmonary infection

Blood Cx – r/o infection

Urine Cx – infection

Abd x-ray – evaluate abdominal pain


TREATMENT

Type I Diabetics

admit : ICU

IVF - isotonic 0.9 NaCl

            1-2 L bolus

            then 500mL /hr until glu<250

            then D5NS

            SE cerebral edema, ARDS

Insulin IV

            Regulin 0.1U/kg loading dose

            If glu does not fall 10% in 1hr repeat loading dose, again if needed, then double dose

            0.1U/kg/hr IV continuous

            until

                        glu normal

                        ketones gone

            drop glu too fast :

                        then cerebral edema

            continuous to avoid ketogenesis

K+

            start once urine output started

            check for hyperkalemia

                        EKG

                        S K+ : do not give if K>5.5

            10meq/hr, if K<4.0=20/hr

NaHCO3

            if pH <7.0 only

Monitor q4h

            ABG - pH

            glu

            Ketones

            lytes - anion gap

Dialysis

            hyperkalemia

           

Once all under control start NPH (18-24h half life SQ) while under regulin (4h)

Gradually wean to sliding scale

 

 

APPROPIATE HEALTH CARE

Inpatient intensive care. This is a life threatening emergency.

Goals are to increase rate of glucose utilization by insulin-dependent tissues, to reverse ketonemia and acidosis, and to correct the depletion of water and electrolytes.

GENERAL MEASURES

IV Fluids adults: 1000 mL over first hour, then 500 mL/hr (approximately 7 mL/kg/hr) x 4 hrs or until dehydration improves, then 250 mL/hour (3.5 mL/kg/hr). Switch to D5 in 1/2 NS when serum glucose < 300 mg/dL (16.65 mmol/l). Expect to give 4-8 L/ first 24 hrs. (Some do not recommend initial IV bolus).

Pediatric maintenance requirements: 100 mL/kg for first 10 kg, 50 mL/kg for second 10 kg and 20 mL/kg thereafter. Fluid deficit: (Multiply patient's body weight by percentage dehydration). Replace maintenance and deficit evenly over 48 hours.

 

ACTIVITY Bedrest

DIET Nothing by mouth initially. Advance to pre-ketotic diet when nausea and vomiting are controlled.

 

PATIENT EDUCATION

For prevention, careful control of blood glucose (usually HgbA1c 7%)

Monitor glucose carefully during periods of stress, infection, trauma etc.


MEDICATIONS

DRUG(S) OF CHOICE

Insulin - initiate infusion at 0.1U/kg/hr

Potassium phosphate orPotassium chloride

Sodium bicarbonate, rarely

 

Contraindications:

No demonstrable clinical benefit from bicarbonate with a pH > 7.0.

Hold K+ if > 5.5 (> 5.5 mmol/L)

 

Precautions:

Double insulin if no response in serum glucose over first 2 hours

Must continue insulin until serum bicarbonate and anion gap normalize

Add dextrose to IV fluid when blood sugar< 300 mg/dL (16.65 mmol/L)

If using bicarbonate, add 50 mg NaHCO3 to 1L 1/2 NS and give over 2 hours

Delay K+ administration in patients with inadequate urine output or evidence of diabetic nephropathy

If blood sugar does not fall by approximately 75 mg % q2h, increase insulin rate

Taper IV insulin and start NPH/Reg insulin after acidosis clears and patient is eating

Significant possible interactions: For each 0.1 unit of pH, serum K+ will change by approximately 0.6 mEq (0.6 mmol/L) K in the opposite direction


FOLLOWUP

PATIENT MONITORING

Monitor mental status, vital signs, urine output q 30-60 minutes until improved, then q2-4 h x 24 hrs

Blood sugar q 1 hr until < 300 mg/dL (16.65 mmol/L), then q2-6h

Potassium, bicarbonate, sodium, anion gap; q 2 hrs

Phosphate, calcium, magnesium; q4-6h

 

PREVENTION/AVOIDANCE

Monitor glucose closely during stressful situations

Careful insulin control

 

EXPECTED COURSE/PROGNOSIS

DKA accounts for 14% of all hospital admissions for diabetes and for 16% of all diabetic related fatalities

Overall mortality of 5-15%

In children < 10 years old, DKA causes 70% diabetes related fatalities

 

Complications

            lactic acidosis

            cerebral edema

            arterial thrombosis