From the Guidelines
The patient's symptoms of intermittent drowsiness, confusion, and hypothermia (32°C) require immediate attention, and treatment should begin with passive rewarming and protection from further heat loss, as recommended by the 2024 American Heart Association and American Red Cross guidelines for first aid 1. The patient's presentation of intermittent drowsiness, confusion, non-pitting edema, and sparse scalp hair, in combination with a temperature of 32°C, suggests hypothyroidism, likely myxedema, which can lead to hypothermia. Key considerations in management include:
- Moving the patient from the cold environment to a warm one
- Removing saturated clothing and providing dry, warm clothing
- Allowing the patient to passively rewarm with blankets
- Considering active rewarming if resources are available, while following the manufacturer's instructions and monitoring for burns and pressure injury 1
- Providing high-calorie foods or drinks if the patient is alert and can safely consume them 1
- Activating the emergency response system if the patient has a decreased level of responsiveness, such as unresponsiveness, inability to remain awake, or confusion 1 Treatment should also include thyroid hormone replacement therapy, specifically levothyroxine (T4), with an initial dose of 25-50 mcg daily, gradually increasing by 25-50 mcg every 2-4 weeks based on clinical response and thyroid function tests. Hospitalization is necessary for close monitoring, and supportive care should include intravenous fluids for possible hypotension and glucose administration if hypoglycemic. In severe cases with myxedema coma, intravenous levothyroxine (300-500 mcg as loading dose) may be required, sometimes with liothyronine (T3) addition. Underlying precipitating factors should be identified and addressed, and thyroid function should be monitored regularly, initially every 4-6 weeks until stable, then every 6-12 months. Hormone replacement is typically lifelong, with dosage adjustments based on TSH levels, aiming for the lower half of the normal range.
From the Research
Treatment Options for Hypothyroidism
The patient's symptoms, such as intermittent drowsiness, confusion, non-pitting oedema, and sparse hair on the scalp, along with a temperature of 32C, may be indicative of hypothyroidism. Based on the provided studies, the following treatment options are available:
- Levothyroxine replacement therapy, started at 1.5 to 1.8 mcg per kg per day, is the standard treatment for hypothyroidism 2, 3, 4.
- Patients older than 60 years or with known or suspected ischemic heart disease should start at a lower dosage of levothyroxine (12.5 to 50 mcg per day) 2.
- For patients with persistent symptoms after adequate levothyroxine dosing, reassessment for other causes or the need for referral is recommended 2, 5.
- Combination therapy with liothyronine (T3) and levothyroxine (T4) may be considered for patients with confirmed overt hypothyroidism and persistent symptoms who have had adequate treatment with levothyroxine and in whom other comorbidities have been excluded 6, 5, 4.
- The decision to start treatment with liothyronine should be a shared decision between patient and clinician, and individual clinicians should not feel obliged to start liothyronine or to continue liothyronine medication provided by other health care practitioners or accessed without medical advice, if they judge this not to be in the patient's best interest 5.
Special Considerations
- Women with hypothyroidism who become pregnant should increase their weekly dosage by 30% up to nine doses per week (i.e., take one extra dose twice per week), followed by monthly evaluation and management 2.
- Patients with subclinical hypothyroidism do not benefit from treatment unless the thyroid-stimulating hormone level is greater than 10 mIU per L or the thyroid peroxidase antibody is elevated 2, 4.