Diabetic Ketoacidosis
Definition
DKA is a metabolic disorder caused by an absence or markedly inadequate amount of insulin.
The metabolism of carbohydrates, proteins and fat are deranged
Pathophysiology
↓Insulin - less glucose enter the cells.
Liver increases glucose production - hyperglycemia
Kideneys excrete glucose and electrolytes (sodium and potassium) - Osmotic diuresis - dehydration and marded electrolyte loss
Lipolysis - fat breaks down to free fatty acids; converted into ketone bodies by the liver
Ketone bodies are acids and lead to metabolic acidosis
Main causes : decreased or missed dose of insulin, illness, infection, undiagnosed and untreated diabetes.
Clinical Features
Hyperglycemia
Dehydration and electrolyte loss
Acidosis
Polyuria, polydipsia
blurred vision
weakness
headache
Orthostatic hypotension with a weak, rapid pulse
Anorexia, nausea, vomiting and abdominal pain
Acetone breath ( a fruity odor)
Hyperventilation (Kussmaul's breathing)
Lethargy, coma
Investigations
Blood sugar 300-800 mg/dl
The severity of the DKA is not necessarily related to the blood glucose level
Low serum bicarbonate (0-15 mEq/L) Low pH (6.8 to 7.3)
Low PCO2 level (10-30 mm Hg)
Urine contains ketone bodies
Na K levels may be reduced
Elevated leves of creatinine, blood urea nitrogen (BUN), Hb,hematocrit
Treatment
Correct hyperglycemia
Correct dehydration - NS at a rapid rate 0.5 to 1 L per hour for 2-3 hours - Half NS for Hypertensives, hypernatremics, and those at risk of heart failure. after 3 hours Half NS is the choice and a rate of 200-500 ml per hour. When BS reaches 300 mg/dL D5 used to prevent excessive fall of blood glucose levels
Correct elctrolyte imbalance and acidosis
I/O chart
Lung assessment
Plasma expanders for severe hypotension
Potassium replacement should be started because there will be intracellular shift of potassium during insulin therapy
ECG every 2 to 4 hours
Insulin infused IV about 5 units per hour: hourly blood glucose estimation. This should be through a separate IV line. Insulin drip continued until acidosis is corrected (bicarbonate dropping to 15-18 mEq/L)
Sodium bicarbonate injection avoided
Nursing Management
Monitor fluid and electrolyte status, blood glucose levels
Administer fluids, insulin and other medications
Look for fluid overloading
Urine output is monitored before administering potassium
ECG - look for dysrrhmias, hypokalemia
Watch urine output
Patient Education
Prevention
Should not reduce insulin dose during illnesses rather should have "Sick Day" doses prescribed.
Frequent drinking fluids every hour
Urine ketone bodies assessed every 4 hours
