Myxedema Coma

Myxedema coma describes a rare, clinical state in which an individual with long-standing preexisting hypothyroidism presents with life-threatening decompensation. 7 In reality, few patients present comatose with severe myxedema. Affected patients are commonly in the geriatric population. Various etiologies may be a precipitant to this syndrome (I§ble 207-4). The clinical presentation is one of a severe decompensated metabolic state that may include an alteration in mental status, hypothermia, bradycardia, hypoventilation, and even cardiovascular collapse ( Table 20Z-5). These findings are not only secondary to a decline in metabolic function but also due to neurovascular and cardiovascular adaptations. Some of these adaptations are similar to those that occur in euthyroid patients exposed to a cold environment (decline in oxygen consumption and heat generation, and redistribution of blood flow centrally). In addition, there is a change in end-organ responsiveness to catecholamines and a decline in cardiac performance. This is due to an absolute diminution in b-adrenergic receptors (decreased inotrope and chronotrope activity). There is also relatively increased a-adrenergic responsiveness resulting in mild diastolic hypertension. 8 Increased CO2 retention occurs because of decreased respiratory muscle strength and diminished ventilatory drive in response to hypercapnia. There is also decreased free-water clearance resulting in a dilutional hyponatremia, impaired gluconeogenesis, and decreased drug clearance that predisposes patients to drug toxicity from medication. 9

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Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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