Transcript Pituitary Tumour - The Thomas Addison Unit

DIABETIC EMERGENCIES
Dr A Panahloo
www.sghms.ac.uk / addison
1. Diabetic Ketoacidosis
2. Hyper-osmolar non-ketotic
coma (HONK)
3. Hypoglycaemia
Diabetic Ketoacidosis (DKA)
Definition:
‘Severe uncontrolled diabetes requiring
emergency treatment with insulin and IV
fluids, and with a blood ketone body
(acetoacetate and 3-hydroxybutyrate)
concentration >5mmol/l’
Diabetic Ketoacidosis (DKA)
Biochemical features:
• Hyperketonaemia
• Metabolic acidosis
• Hyperglycaemia
Incidence and mortality
• Annual incidence 1-5 episodes per 100
Type-1 diabetic patient
• Peak in adolescence
• Twice as common in females
• Average mortality 5-10%
• Mortality rises with age, 50% > 80 years
Precipitating Factors
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Infection (30%)
New cases of type-1 diabetes (10%)
Insulin error (patient or doctor) (13%)
Myocardial infarction (1%)
Unknown cause (40%)
Miscellaneous (6%)
Differential Diagnosis
Causes of anion-gap acidosis:
• Ketoacidosis
• Type-1 diabetes
• Alcoholic abuse
• Starvation (acidosis is mild)
• Lactic acidosis
• Chronic renal failure
• Drug toxicity
• Methanol (metabolized to formic acid)
• Ethylene glycol (metabolized to oxalic acid)
• Salicylate poisoning
Clinical features-symptoms:
– Polyuria and polydipsia
– Weight loss and malaise
– Weakness
– Anorexia
– Blurred vision
– Nausea and vomiting
– Abdominal pain, especially in children
– Breathless (acidotic respiration)
– Confusion and drowsiness
– Coma (10% of cases)
Clinical signs:
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Dry mouth
Facial flush
Ketotic breath
Postural hypotension
Tachycardia
Kussmaul breathing (deep rapid resps.)
Depression of consciousness
Coma
Fluid and Electrolyte Depletion:
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Sodium
Chloride
Potassium
Calcium
Phosphate
Magnesium
500 mmol
350 mmol
300-1000 mmol
50-100 mmol
50-100 mmol
25-50 mmol
Management
• Rapid confirmation of diagnosis:
– BM,smell ketones,urine ketostix
• Blood:
– Glucose, U+E,FBC,gases, blood cultures
• Look for precipitating cause eg infection
• Asses severity of dehydration
• If comatosed nurse in coma position,
naso-gastric tube and urinary catheter
Other Investigations:
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Ketone bodies
ECG
Chest X-ray
Urine and sputum for culture
Management
• Fluid replacement
• Insulin
• Correction of electrolyte imbalance
Fluids
• Deficit my be 5-10 litres
• If systolic BP < 100mmhg or shocked
– colloid or 500 mls N/saline over 15 min
– then 1000 mls N/saline over 1 hour (no K+)
• If not shocked
– 1000 mls N/saline over 1 hour
Fluids
• Continue N/saline +K according to need
• Asses BP, CVP and urine output
• Repeat Glucose, U+E, blood gases
4 hourly
• Convert to 5% dextrose infusion when
BG < 15 mmol
Insulin
• Soluble insulin via a pump
• No indication for bolus dose or s/c or IM
injections
• No indication for sliding scale
• Aim to reduce glucose by 3 mmol/h
• When glucose <15 mmol use dextrose
• Continue insulin and dextrose until
acidosis clears
Potassium
• Total deficit may be very high
• K is intracellular, insulin and rising pH
cause entry of K in cells
• Serum levels may be high, low or
normal and do nor reflect total body
status
• Main danger hypokalaemia
• Replace 20-40 mmol K per litre of fluid
Bicarbonate
• Controversial
• Contraindicated unless severe acidosis
+ cardio-respiratory collapse imminent
• Shifts K+ into cells
• Worsens hypokalaemia
• CO enters brain reduces CSF pH
• Cerebral oedema results
• adverse O2 tissue delivery
Complications
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Cerebral oedema
Arterial and venous thrombosis
Secondary infection in urine, chest
Adult respiratory distress syndrome
Thrombophlebitis
Rhabdomyolysis
Prevention
• Sick day rules:
– Never stop insulin and check for ketones
– Measure BMs 4 times a day
– If BM < 11 mmol continue normal insulin
– If BM 11-17 mmol add extra 4 u with meals
– If BM > 17 mmol add extra 6 u with meals
Drink milk, fruit juice, 5 pints sugar free
fluid /day
– If nausea and vomiting and BM >17 call Dr.
Hyperosmolar non-ketotic coma
(HONK)
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Non-ketotic hyperglycaemia
Relative insulin deficiency
BG much higher than DKA (>50 mmol)
Develops slowly over weeks
Severe dehydration
Impaired Consciousness
High serum Na >150 mmol/l
HONK- Diagnosis
• Raised plasma glucose (50- 100 mmol)
• Increased plasma osmolality (> 340
mosm/l, measured in lab or calculated:
• P.osmolality (mosmol/l) =
2 x [plasma Na+ + plasma K+] + plasma
[glucose] + plasma [urea]
• No ketosis and no acidosis
HONK- incidence and mortality
• Accounts for 10-30% of hyperglycaemic
emergencies
• Mortality 30% due to associated
conditions and complications
• Most patients age >50 years
• Higher incidence in Afro-Caribbean
patients
• 50% undiagnosed diabetes
HONK- Clinical features
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Develops over several weeks
Polyuria, polydipsia
Gradual clouding of consciousness
Severe dehydration
Hypotension
Reversible neurological signs
Comatosed
Comparison DKA:HONK
DKA
HONK
AGE
CAUSE
YOUNG TYPE-1
INSULIN DEFFICIENCY
Na
GLUCOSE
BICARBONATE
KETONES
MORTALITY
COURSE
NORMAL / LOW
< 40 mmol
< 14 mmol/l
POSITIVE
5-10%
TYPE-1
OLDER TYPE-2
DIURETICS
STEROIDS
50% UNKNOWN DM
HIGH
> 40 mmol
NORMAL
NEGATIVE
30-50 %
OFTEN DIET ALONE
Fluids in HONK
• Initial fluid, electrolyte and insulin
therapy is similar to DKA
• If Na >150 mmol/l half normal saline
• Patients more sensitive to insulin
• Start insulin infusion at slower rate
eg 3 units / hour
• Fewer K+ problems
• Anticoagulation
Hypoglycaemia
• Common side-effect of treatment with
insulin or sulphonylureas
• Does not occur with Metformin or diet
alone
• Each year 25-30% of all insulin treated
patients have one or more episodes of
severe hypoglycaemia
Hypoglycaemia
• Predisposing factors
– Inadequate food intake
– Excess dosage, error by patient or Dr
– Exercise
– Weight loss
– Alcohol
– Adrenocortical, thyroid or pituitary failure
– Renal failure
Hypoglycaemia
• Asymptomatic (biochemical), awake or
asleep
• Mild symptomatic- patient able to treat
themselves
• Severe symptomatic- help needed to
treat hypoglycaemic attack
• Coma
Hypoglycaemia- hierarchy of events
Blood glucose:
• 4.6 mmol
• 3.8 mmol
• 3.0 mmol
• < 2.8 mmol
Inhibition of insulin
secretion
Release of glucagon and
adrenaline
Hypoglycaemic
symptoms
Cognitive function
progressively impaired
Hypoglycaemia - symptoms
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Autonomic
– Sympathetic or parasympathetic
– eg sweating, palpitations, tremor or hunger
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Neuroglycopenic
– eg confusion, clumsiness, behavioural
changes, temper tantrums in children
Hypoglycaemia - symptoms
• Acute
– Lassitude
– light headed
– tremor
– restless
– cold sweat (diversion of blood from skin
and kidneys to brain, liver and muscle)
Hypoglycaemia - symptoms
• Sub-acute
– Slow movement and thoughts
– Immobility
– Slow speech
– Detachment
– Automatism and amnesia
– Confusion
– Drowsy
– Manic
Hypoglycaemia - symptoms
• Chronic
– Rare
– Obsessional control of diabetes
– Symptoms absent
– Personality disorder
– Apparent dementia
Hypoglycaemia - treatment
• Mild
• Treat immediately with oral glucose (15-20g)
• If patient unable to swallow
• IV 50% dextrose 30-50 mls)
• IM glucagon (1mg)
• Patients should recover immediately
• Failure to recover may be due to
cerebral oedema, postictal state or
other causes of coma
Hypoglycaemia - treatment
• Hypoglycaemia induced by
sulphonylureas may be very prolonged
• May need IV glucose for hours or even
days