Hyperglycaemia

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Hyperglycaemia
Diabetes Outreach
(August 2011)
Hyperglycaemia
Learning objectives
> Can state what hyperglycaemia is
> Is aware of the short term and long term
complications associated with hyperglycaemia
> Can state what causes hyperglycaemia
> Is aware of the management and prevention
of diabetic ketoacidosis (DKA) and
hyperglycaemic hyperosmolar state (HHS).
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What is hyperglycaemia?
> defined as a fasting BGL ≥7mmol/L and post
prandial ≥11.1mmol/L
> symptoms usually occur when BGL >15mmol/L
> if not treated hyperglycaemia can lead to
> diabetic ketoacidosis (type 1)
> hyperglycaemic hyperosmolar state (type 2).
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Primary causes of hyperglycaemia
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insufficient insulin or omission
insufficient OHAs or omission
infection and illness
surgery
excessive carbohydrate intake
stress
rebound hyperglycaemia
other medications eg steroids.
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Hyperglycaemic hyperosmolar
state (HHS)
> significant mortality (15%)
> occurs most frequently in elderly people with
type 2
> life threatening with severe hyperglycaemia
leading to severe dehydration.
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What happens in HHS
can be gradual
Very high BGL
(body tries to get rid of the glucose via the kidneys - polyuria
polydipsia)
Electrolyte imbalance and dehydration
(every time the body gets rid of excess glucose it sucks out
more fluid and this disrupts electrolytes like potassium in the
body)
Impaired conscious state
(The body is unable to replace all the fluids lost
and the person is now in danger of severe dehydration)
Coma and possible DEATH
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Signs of HHS
Fluid movement from the cell and dehydration
lead to:
> decreased skin elasticity
> low blood pressure
> fever
> drowsiness
> confusion
> convulsion and coma.
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Management of HHS
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hospitalisation
rehydration (because of dehydration)
insulin therapy (because of high BGL)
monitor glucose and electrolyte balance
continue observation of vital signs
identify precipitating factors.
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Prevention of HHS
What can health professionals do to prevent
HHS?
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Diabetic ketoacidosis (DKA)
> Results from an absence of insulin (type 1
diabetes only).
> Low levels of insulin means that glucose
cannot nourish cells.
> Tissues become starved for glucose.
> To prevent cell death from starvation the body
breaks down fat and muscle for energy,
resulting in a bi-product called ketones.
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What happens in DKA?
Insulin deficiency
↓ glucose
lipolysis
ketogenesis
glycogenolysis
gluconeogenesis
hyperglycaemia
ketosis
acidosis
uptake into
tissue
osmotic diuresis
vomiting
severe dehydration
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Causes and contributing factors
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illness or infection
inadequate insulin dose
first presentation of type 1 diabetes
myocardial infarction, CVA
trauma, surgery.
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Clinical features of DKA
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signs of hyperglycaemia
dehydration
ketonuria
electrolyte imbalance
hyperventilation (Kussmaul’s)
ketotic breath
gastro intestinal (nausea, vomiting,
abdominal pain)
> disturbed conscious state and shock.
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DKA treatment
Goals:
> to correct fluid and electrolyte imbalance
> to correct metabolic acidosis
> provide insulin to correct acidosis and lower
blood glucose
> identify precipitating factors to prevent
recurrence.
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DKA Treatment
Assessment and history:
> laboratory analysis
> electrolyte and osmolality
> (K+ and Na NCO3)
> arterial blood gas (metabolic acidosis)
> state of dehydration
> cause of ketoacidosis.
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DKA treatment
Management:
> start insulin infusion at 5-8 units per hour via an infusion
pump
> replace fluids with normal saline (eg give 2000ml over 2
hrs)
> start potassium replacement from 3rd litre of NS
> once BSL ≤ 12mmol/L switch fluid replacement to 4%
DextroseN/5saline or 5% Dextrose
> do not stop potassium replacement unless hyperkalemic
> treat underlying precipitant- infection/ MI
> consider DVT prophylaxis
> once acidosis is corrected and oral intake in place start
basal bolus insulin regimen
> allow infusion to overlap with long acting insulin for a
couple of hours.
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Prevention
> patient and family education
> appropriate sick day management
> ketone testing in type 1 diabetes, during
illness or when BGL is 15mmol/L
> staff education with regard to diagnosis and
treatment
> consideration of psychological aspects.
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Sick day action plans
> All people (regardless of diabetes type)
should have a sick day action plan.
> A sick day action plan describes
> when to follow sick day guidelines
> how to self manage sick days
> when to seek help.
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Summary
Hyperglycaemia needs to be managed in a
timely and proactive way.
All people with diabetes should receive
education about hyperglycaemia and be
stepped through a sick day action plan.
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References
> Diabetes Outreach (2009) Diabetes Manual,
Section 11: Unstable diabetes
> Kitabachi, A. E., G. E. Umpierrez, et al.
(2001). "Management of hyperglycemic crisis
in patients with diabetes." Diabetes Care
24(1): 131-153.
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