eMedicine Specialties > Emergency Medicine > Endocrine & Metabolic

Hypothyroidism and Myxedema Coma: Follow-up

Author: Erik D Schraga, MD, Consulting Staff, Department of Emergency Medicine, Mills-Peninsula Emergency Medical Associates; Consulting Staff, Permanente Medical Group, Kaiser Permanente, Santa Clara Medical Center
Contributor Information and Disclosures

Updated: Dec 10, 2009

Follow-up

Further Inpatient Care

  • Admit patients with myxedema coma to ICU.
  • Provide supportive ventilatory and hemodynamic management.
  • Treat precipitating events (eg, infection).
  • Continue rewarming as required.
  • Confirm diagnosis with laboratory testing.
  • Continue thyroid hormone replacement, and convert to oral therapy when tolerated.
  • Clinical improvement should be apparent within 24-36 hours of initiating thyroid hormone replacement.

Complications

  • Treatment-induced congestive heart failure in patients with coronary artery disease
  • Myxedema coma
  • Increased susceptibility to infection
  • Megacolon
  • Organic psychosis with paranoia
  • Adrenal crisis with vigorous treatment of hypothyroidism
  • Hypersensitivity to opiates
  • Pericardial effusion and cardiac tamponade4

Prognosis

  • The prognosis of hypothyroidism is good with early treatment. However, once the disease has progressed to myxedema coma, the mortality rate may exceed 20% in the treated population.
  • Relapses occur if treatment is discontinued.

Patient Education

  • Importance of medication compliance
  • Need for lifelong treatment
  • Watch for signs of infection
  • Watch for signs of thyrotoxicity
  • For excellent patient education resources, visit eMedicine's Endocrine System Center. Also, see eMedicine's patient education articles Thyroid Problems and Myxedema Coma.

Miscellaneous

Medicolegal Pitfalls

  • Failure to consider the diagnosis in the setting of altered mental status
    • Myxedema coma is rare and associated with significant signs and symptoms that may overshadow the underlying diagnosis.
    • Always consider myxedema coma in patients with altered mental status and in those who have been on thyroid medication or had thyroid surgery.
  • Hypothyroid patients, especially those with myxedema coma, often are hypothermic. A normal or elevated temperature can reflect underlying infection.
  • Failure to further evaluate and treat additional etiologies of altered mental status

Special Concerns

  • Patients with hyperammonemia and altered level of consciousness may easily be misdiagnosed as having hepatic encephalopathy. Both may have a similar presentation of obtundation/coma, ascites, liver malfunction, and anemia.5
 
Acknowledgments

The authors and editors of eMedicine gratefully acknowledge the contributions of previous author, Craig A Manifold, DO, to the development and writing of this article.



More on Hypothyroidism and Myxedema Coma

Overview: Hypothyroidism and Myxedema Coma
Differential Diagnoses & Workup: Hypothyroidism and Myxedema Coma
Treatment & Medication: Hypothyroidism and Myxedema Coma
Follow-up: Hypothyroidism and Myxedema Coma
Multimedia: Hypothyroidism and Myxedema Coma
References
Further Reading
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References

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  2. [Best Evidence] Teng W, Shan Z, Teng X, Guan H, et. al. Effect of iodine intake on thyroid diseases in China. N Eng J Med. Jun 2006;354(26):2783-2793. [Medline].

  3. Lee CH, Wira CR. Severe angioedema in myxedema coma: a difficult airway in a rare endocrine emergency. Am J Emerg Med. Oct 2009;27(8):1021.e1-2. [Medline].

  4. Sanda S, Newfield RS. A child with pericardial effusion and cardiac tamponade due to previously unrecognized hypothyroidism. J Natl Med Assoc. Dec 2007;99(12):1411-3. [Medline].

  5. Ragland G. Hypothyroidism and myxedema coma. In: Tintinalli JE, Krome RL, et al, eds. Emergency Medicine: A Comprehensive Study Guide. 4th ed. New York, NY: McGraw-Hill; 1996:964-67.

  6. Flynn RW, MacDonald TM, Morris AD. The thyroid epidemiology, audit, and research study: thyroid dysfunction in the general population. J Clin Endocrinol Metab. Aug 2004;89(8):3879-84. [Medline].

  7. Franklyn JA. The management of hyperthyroidism. N Engl J Med. Jun 16 1994;330(24):1731-8. [Medline].

  8. Hehrmann R. [Coma in myxedema--a rare complication of hypothyroidism. Possible iatrogenic factors should be taken into account]. Fortschr Med. Dec 10 1996;114(34):474-8. [Medline].

  9. Kinuya S, Michigishi T, Tonami N, et al. Reversible cerebral hypoperfusion observed with Tc-99m HMPAO SPECT in reversible dementia caused by hypothyroidism. Clin Nucl Med. Sep 1999;24(9):666-8. [Medline].

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  16. Vanderpump MP, Tunbridge WM, French JM, et al. The incidence of thyroid disorders in the community: a twenty-year follow-up of the Whickham Survey. Clin Endocrinol (Oxf). Jul 1995;43(1):55-68. [Medline].

  17. Wang C, Crapo LM. The epidemiology of thyroid disease and implications for screening. Endocrinol Metab Clin North Amer. 1997;26(1):189-218. [Medline].

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  20. Yamamoto T, Fukuyama J, Fujiyoshi A. Factors associated with mortality of myxedema coma: report of eight cases and literature survey. Thyroid. Dec 1999;9(12):1167-74. [Medline].

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Further Reading

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Keywords

hypothyroidism, myxedema coma, Hashimoto thyroiditis, Riedel struma, idiopathic hypothyroidism, cretinism, endemic goiter, primary hypothyroidism, secondary hypothyroidism, control hypothyroidism, goitrous hypothyroidism, treatment, diagnosis, symptoms

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Contributor Information and Disclosures

Author

Erik D Schraga, MD, Consulting Staff, Department of Emergency Medicine, Mills-Peninsula Emergency Medical Associates; Consulting Staff, Permanente Medical Group, Kaiser Permanente, Santa Clara Medical Center
Disclosure: Nothing to disclose.

Medical Editor

Jerome FX Naradzay, MD, FACEP, Medical Director, Consulting Staff, Department of Emergency Medicine, Maria Parham Hospital; Medical Examiner, Vance County, North Carolina
Jerome FX Naradzay, MD, FACEP is a member of the following medical societies: American Academy of Emergency Medicine, American College of Emergency Physicians, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: eMedicine Salary Employment

Managing Editor

Howard A Bessen, MD, Professor of Medicine, Department of Emergency Medicine, UCLA School of Medicine; Program Director, Harbor-UCLA Medical Center
Howard A Bessen, MD is a member of the following medical societies: American College of Emergency Physicians
Disclosure: Nothing to disclose.

CME Editor

John D Halamka, MD, MS, Associate Professor of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center; Chief Information Officer, CareGroup Healthcare System and Harvard Medical School; Attending Physician, Division of Emergency Medicine, Beth Israel Deaconess Medical Center
John D Halamka, MD, MS is a member of the following medical societies: American College of Emergency Physicians, American Medical Informatics Association, Phi Beta Kappa, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Chief Editor

Rick Kulkarni, MD, Assistant Professor of Surgery, Section of Emergency Medicine, Yale-New Haven Hospital
Rick Kulkarni, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Emergency Medicine, American College of Emergency Physicians, American Medical Association, American Medical Informatics Association, Phi Beta Kappa, and Society for Academic Emergency Medicine
Disclosure: WebMD Salary Employment

 
 
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