Editing Diabetic ketoacidosis

== '''Pathophysiology''' ==

* Caused by a relative lack of insulin; leading to high levels of glucagon, cortisol, and adrenaline; that stimulates lipolysis; leading to increased circulating free fatty acids, which are directed to the ketogenesis pathway in the liver
* Can occur in T2DM when patients are relatively insulin-deficient and there is intercurrent illness and dehydration which stimulates counter-regulatory hormone secretion (especially glucagon)
* Correction of hypovolaemia will often improve acidosis and hyperglycaemia, along with insulin infusion
* Abdominal pain is present in 46% of patients with DKA, but uncommon in HHS. It can be caused by ileus, gastroparesis and electrolyte abnormalities. Seek alternative aetiologies such as pancreatitis if pain persists after correction of DKA.

== '''Triggers''' ==

* Non-compliance
* Infection
* Trauma
* Pregnancy
* Infarction
* Cocaine

== '''Presentation''' ==

* Nausea/vomiting, thirst, dyspnoea
* Tachycardia, dehydration/hypotension, tachypnoea, abdominal tenderness, lethargy/obtundation/cerebral oedema/coma

== '''Diagnosis''' ==

* Triad of hyperglycaemia, ketonaemia, and high anion gap metabolic acidosis (usually the major finding)
* Euglycaemic DKA can occur in starvation, pregnancy, pre-treatment with insulin, or SGLT-2 inhibitors

{| class="wikitable"
| 
|'''DKA'''
|
|
|'''HHS'''
|-
|
|'''Mild'''
|'''Moderate'''
|'''Severe'''
|
|-
|'''Plasma glucose (mmol/L)'''
|>13.9
|>13.9
|>13.9
|>33.3
|-
|'''Arterial pH'''
|7.25 to 7.30
|7.00 to 7.24
|<7.00
|>7.30
|-
|'''Serum bicarbonate (mEq/L)'''
|15 to 18
|10 to <15
|<10
|>18
|-
|'''Urine ketones'''¶
|Positive
|Positive
|Positive
|Small
|-
|'''Serum ketones – Nitroprusside reaction'''
|Positive
|Positive
|Positive
|≤ Small
|-
|'''Serum ketones – Enzymatic assay of beta hydroxybutyrate (normal range <0.6 mmol/L)'''Δ
|3 to 4 mmol/L
|4 to 8 mmol/L
|>8 mmol/L
|<0.6 mmol/L
|-
|'''Effective serum osmolality (mOsm/kg)'''◊
|Variable
|Variable
|Variable
|>320
|-
|'''Anion gap'''§
|>10
|>12
|>12
|Variable
|-
|'''Alteration in sensoria or mental obtundation'''
|Alert
|Alert/drowsy
|Stupor/coma
|Stupor/coma
|}

== '''Differential diagnosis''' ==

* Alcoholic ketoacidosis: ketoacidosis without hyperglycaemia in a patient with chronic alcoholism is virtually diagnostic of AKA
* Fasting ketoacidosis: ketones usually only mildly elevated, with serum bicarb usually >17
* Other causes of anion-gap acidosis
* '''Euglycaemic DKA secondary to SGLT-2 inhibitors'''
** See separate topic under 'peri-op diabetes'

== '''Management''' ==

=== '''Resuscitate''' ===

** 2-3L of 0.9% N/S over 1-3 hours, then run at 250ml/hr
** Change to 5% dextrose at 150-250ml/hr when BSL < 13.9
** K+ > 3.3
** Review triggers, identify cause

=== '''Insulin infusion''' ===

** Bolus of 0.1 U/kg IV short-acting insulin given immediately
** 0.1 U/kg/hr by continuous infusion (once potassium ok)
** Increase 2-3x if no response by 4 hours
** Measure BSL hourly
** VBG q4h, especially for K+
** Cease when the patient is stable, BSL 8.3-11.1, and acidosis is resolved
** Give long-acting insulin as soon as the patient is eating, then remove the insulin infusion 2-4 hours later


[[Category:Endocrinology]]