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MYXEDEMA COMA
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MYEDEMA COMA
End stage of untreated or insufficiently treated
hypothyroidism
Typical clinical picture: Elderly obese female
Becoming increasingly withdrawn, lethargic, sleepy and
confused
Slips into a coma
History: Previous thyroid surgery
Radioiodine
Default thyroid hormone therapy
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Precipitating Events
Cerebrovascular accidents
Myocardial infarction
Infection UTI
Pneumonia
Gastrointestinal hemorrhage
Acute trauma Administration of sedative, narcotics,
tranquilizers,
potent diuretics
CCF
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Pathogenesis of Myxedema coma
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Symptoms
Cold intolerance, dry skin
Constipation, weight gain, poor appetite
Neurological-weakness, slow speech,disorientation ,apathy,
psychosis
Symptoms progress to lethargy, disorientation,
grandmal seizures, coma
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Physical Findings
Comatose or semi comatose
Dry coarse skin, cold peripheries
Puffy face, hands, feet
Bradycardia
Delayed reflex relaxation time
Hypothermia, hypotension,hypoventillation
Pericardial, pleural effusions, ascites
GI ileus, urinary retention
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Lab Findings
Free T4-low and TSH-high
If TSH-low/N and FT4-low, consider central orpitutary
hypothyroidism.
Blood gases-hypoxemia, hypercapnia, acidosis
Hypoglycemia, hyponatremia
Blood culture, urine culture, CXR
ECG
LFT,RFT Distinguish from euthyroid sick syndrome
Low T3, Normal or low TSH, normal free T4
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Management of Myxedema coma
ICU admission is required for
ventilatory support, continuousclose monitoring of pulmonary
and
cardiac status
IV medications
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General & supportive
1. ABC
2. IV access-large bore 18 guage
3. Fluid replacement
isotonic crystalloid solutions like NS/RL
Avoid hypotonic solutions
Avoid vasopressors-risk of dysrythmia
4. Treatment of hypothermia-corrected once T4is administered
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Treatment of hypoglycemia -50% Dextrose
initially. Then 5%Dextrose infusion in NS/RL
Glucocorticoids-Hydrocortisone Na
phosphate/succinate 100mg every 8hrs for
48hrs.Then taper over 1 week
Treat the precipitating cause
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Specific Therapy
Parenteral thyroxine
Loading dose of 200500 g T4, IVover 1 hr
Then 50-100 g daily until oral intake
is tolerated
Controversy exists as to whether to give T3,
in addition to T4
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Treatment
Hypothyroidism
Hypocortisolemia
Hypoventillation
Hypothermia
Hyponatremia
Hypotension
Hypoglycemia
IV 200-500 g loading doseT4.Then 50-100 g
IV hydrocortisone 100mg8hrly
Intubation, mechanicalventilation
Blankets, no active methods
Cautious fluid replacement
Volume expansion-crystalloids
Dextrose
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Prognosis
When recognized & treated early, mortality is
15-20%, and is mostly due to underlying and
precipitating diseases.
If not recognized early, mortality is 60-70%,
especially in elderly.
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Thank you
