Anestesia y Disfunción Tiroidea Dr Raúl Fernando Vásquez

Endocrinopatias Endocrinologia Terapia Hormonas = Homeostasis Frecuente Hormonas = Homeostasis Terapia The endocrinology concerns all anesthesiologists for three reasons: I) The anesthesiologist often encounters endocrine problems. The endocrinopathy may be the primary disorder for which surgery is being performed, or it may be a secondary problem in a patient about to have surgery for a nonendocrine reason. 2) Hormones mediate many of the body's homeostatic responses to surgical stress, critical illness, and injury. In so doing, plasma hormone concentrations may be altered, making diagnosis of an endocrine disorder difficult perioperatively. 3) With increased frequency, hormones are being used as therapeutic agents for nonendocrine problems. For example, desmopressin (DDAVP) (a synthetic analog of the neurohypophyseal nonapeptide arginine, vasopressin) is used to treat diabetes insipidus. However, it is being used to reduce blood loss after cardiac surgery, after Harrington rod spinal fusion surgery, and in patients with hemostatic disorders (such as uremia, hemophilia, and von Willenbrand's disease).I -s Other uses of DDAVP include such diverse indications as reduction of spinal headache after lumbar puncture.s This review on perioperative endocrine problems focuses on three specific problems-thyroid disorders, adrenal cortical insufficiency, and pituitary lesions. Clinical implications for the practicing anesthesiologist are emphasized.

Disfunción Tiroidea Afecta principalmente el sistema cardiovascular Puede ser estabilizada en cirugia electiva y de emergencia mejorando resultados Es tarea del anestesiologo educar al cirujano sobre los peligros de no optimizar la funcion tiroidea preoperatoriamente Patients with preoperative endocrinopathies represent a particular challenge not only to anesthesiologists but also to surgeons and perioperative clinicians. Fleisher: Anesthesia and Uncommon Diseases, 5th ed.

Fisiología Activo 0.3% Libre VM 12h Excreción _ Estimulan TRH AMPc HIPOTALAMO HIPOFISIS TIROIDES HIGADO INTESTINO CELULA Activo 0.3% Libre VM 12h Excreción _ Fisiología Estimulan TRH AMPc Teofilina Epinefrina Inhiben Dopamina Somatostatina Estrogenos Glucocorticoides _ O OH I NH2 Thyroxine (T4) 3,5,3’-Triiodothyronine (T3) Pituitary TSH release is initiated from the ventromedian hypothalamus by thyrotropin-releasing hormone (TRH). TRH is carried from the hypothalamus to the anterior pituitary via the hypophyseal portal venous system. Hypothermia in both the rat (22) and in the human infant (23) augments TRH release from the hypothalamus. Hypothermia-induced TRH release, through TRH-mediated increases in T3 and T4 secretion, elevates the basal metabolic rate (BMR) to counter decreases in core body temperature. TSH is the major regulator of thyroid structure and function. A decrease in TSH causes a reduction in synthesis and secretion of T4 and T3, a decrease in follicular cell size, and a decrease in the gland’s vascularity. An increase in TSH yields an increase in hormone production and release and an increase in gland cellularity and vascularity Upon entering the blood, T4 and T3 bind reversibly to three major proteins: thyroxine binding globulin (80% of binding), prealbumin (10%–15%), and albumin (5%–10%). Only the small amount of free fraction of hormone, however, is biologically active. The remainder serves as a metabolically inert reservoir. The elimination half-life (T1/2) of T4 is 7 to 8 days and the T1/2 of T3 is 3 days. Although only 10% of thyroid hormone secretion is T3, T3 is three to four times more active than T4 per unit of weight and may be the only active thyroid hormone in peripheral tissues. The majority of T3 (75%) is derived from monodeiodination of T4 in the periphery. Ninety percent of thyroid hormone bound intracellularly is T3 and 10% is T4 75% a 85% Fleisher: Anesthesia and Uncommon Diseases, 5th ed.

Fisiología Tiroidea Douglas C. Bauer. Pathophysiology of Disease 

Disfunción Tiroidea La Hormona tiroidea estimula todos los procesos metabólicos Sintéticos Catabólicos Síndromes clínicos Hipo metabolismo Híper metabolismo Current Opinion in Anaesthesiology 1997,10:244-247

THYROID HORMONE AND THE CARDIOVASCULAR SYSTEM IRWIN KLEIN , M. D THYROID HORMONE AND THE CARDIOVASCULAR SYSTEM IRWIN KLEIN , M.D., AND KAIEO JAMAA, PH.D Effects of Thyroid Hormone on Cardiovascular Hemodynamics. The diagram shows the way in which triiodothyronine increases cardiac output by affecting tissue oxygen consumption (thermogenesis), vascular resistance, blood volume, cardiac contractility, and heart rate. adapted from Klein and Levey, 6 with the permission of the publisher. It is clear from many invasive and noninvasive measurements in patients with thyroid disease that cardiac functions such as heart rate, cardiac output, and systemic vascular resistance are closely linked to thyroid status In addition to the well-recognized action of thyroid hormone to increase peripheral oxygen consumption and substrate requirements, which causes a secondary increase in cardiac contractility, the hormone also increases cardiac contractility directly. 2-4 Triiodothyronine decreases systemic vascular resistance by dilating the resistance arterioles of the peripheral circulation. 13 The vasodilation is due to a direct effect of triiodothyronine on vascular smooth-muscle cells that promotes relaxation. 14 The clinical correlate of this finding is that a high dose of triiodothyronine decreases systemic vascular resistance and increases cardiac output within hours after coronary-artery bypass grafting. 15 Thyroid hormone increases blood volume. 6 As a result of the decrease in systemic vascular resistance, the effective arterial filling volume falls, causing an increase in renin release and activation of the angiotensin– aldosterone axis. 16 This, in turn, stimulates renal sodium reabsorption, leading to an increase in plasma volume. Thyroid hormone also stimulates erythropoietin secretion. The combined effect of these two actions is an increase in blood volume and preload, which further increases cardiac output N Engl J Med, Vol. 344, No. 7

THYROID HORMONE AND THE CARDIOVASCULAR SYSTEM IRWIN KLEIN , M. D THYROID HORMONE AND THE CARDIOVASCULAR SYSTEM IRWIN KLEIN , M.D., AND KAIEO JAMAA, PH.D *The values for patients with hyperthyroidism and those with hypothyroidism are taken from Klein and Levey, 6 Graettinger et al., 7 Mintz et al., 8 Biondi et al., 9 Wieshammer et al., 10 Forfar et al., 11 Feldman et al., 12 Park et al., 13 Ojamaa et al., 14 and Klemperer et al. 15 Although atrial arrhythmias are common and ventricular ectopy is rare in patients with hyperthyroidism, the opposite is true of hypothyroidism.4,23 Hypothyroidism prolongs the cardiac action potential and the QT interval.31 This, in turn, predisposes the patient to ventricular irritability and, in rare cases, acquired torsade de pointes.52 Hypothyroidism may result in accelerated atherosclerosis and coronary artery disease, presumably because of the associated hypercholesterolemia and hypertension N Engl J Med, Vol. 344, No. 7

THYROID HORMONE AND THE CARDIOVASCULAR SYSTEM IRWIN KLEIN , M. D THYROID HORMONE AND THE CARDIOVASCULAR SYSTEM IRWIN KLEIN , M.D., AND KAIEO JAMAA, PH.D Sites of Action of Triiodothyronine on Cardiac Myocytes. Triiodothyronine enters the cell, possibly by a specific transport mechanism, and binds to nuclear triiodothyronine receptors. The complex then binds to thyroid hormone response elements of the genes for several cell constituents and regulates transcription of these genes, including those for Ca2+ -ATPase and phospholamban in the sarcoplasmic reticulum, myosin, B -adrenergic receptors, adenylyl cyclase, guanine-nucleotide binding proteins, Na+ /Ca 2+ exchanger, Na + /K + –ATPase, and voltage-gated potassium channels. Nonnuclear triiodothyronine actions on ion channels for sodium (Na + ), potassium (K + ), and calcium (Ca 2+ ) ions are indicated at the cell membrane. Dashed arrows indicate pathways with multiple steps, and mRNA denotes messenger RNA. N Engl J Med, Vol. 344, No. 7

Hipotiroidismo Prevalencia 1% > en mujeres Primario 95% T4 libre < 5pmol/L + TSH normal o elevada frecuentemente > 10mU/L > Iatrogenia 40% a 50% Cx o iodo radioactivo : hipotiroidismo en 10 años Tiroiditis de Hashimoto Anesthesiology Clin 27 (2009) 687–703 - ANESTHESIA AND ANALGESIA Vol 61, No 4

Hipotalamo (TRH) Hipofisis (TSH) Tiroidea TBG Sobre conversión TIROIDES HIGADO INTESTINO CELULA Activo Excreción Hipotalamo (TRH) Hipofisis (TSH) Tiroidea TBG Sobre conversión Subconversión Disbacteriosis Disfunción receptor Autoinmune www.themegallery.com

Hipotiroidismo Signos y Síntomas comunes Letargia Fatiga Anorexia Cefalea Disfonia Depresión Intolerancia al frio Edema periferico periorbitario Constipacion The apathy and lethargy that often accompany hypothyroidism often delay its diagnosis, so that the perioperative period may be the first place to spot many such hypothyroid patients Anesthesiology Clin 27 (2009) 687–703

Hipotiroidismo Indice metabolico Sistema CV Sistema respiratorio Otros 55% a 60% normal Sistema CV Bradicardia, ↑RVS hipertension, presion de pulso disminuida, derrame pericardico, cardiopatia dilatada Sistema respiratorio Disminucion del drive hipoxico hipercapnico Otros ↓Volumen plasmatico 10% a 25%, hiponatremia, ↑ agua extracelular total, ↓factor VIII y IX, dislipidemia This is due to a decrease in both the content and activity of mitochondria1 enzymes producing a general slowing of substrate oxidation. The result is a decreased ability to increase core temperature in response to low temperature stress (45), rendering the hypothyroid patient particularly susceptible to intraoperative and postoperative hypothermia It is felt that the interstitial mucopolysaccharide depositions characteristic of myxedema “exert sufficient colloid osmotic pressure to oppose that of plasma protein and so lead to a transfer of saline from plasma to the interstitial fluids . . . This accounts for the peculiar clinical characters of myxedematous swellings and for the low total volume and high protein content of the plasma in this disease” (65). Also, impairment of free water excretion contributes to the hyponatremia because of changes in renal hemodynamics, with decreases in glomerular filtration rates and in creatinine clearance, as well as reductions in tubular transport (66). Inappropriate secretion of vasopressin has also been demonstrated (67). These changes give rise to postoperative fluid and electrolyte imbalances Anesthesiology Clin 27 (2009) 687–703

Por que es Importante? Hipotiroidismo Incidencia de morbilidad peri – operatoria desconocida Hipotension severa Arresto cardiaco post induccion Sensibilidad extrema los narcoticos Inconciencia prolongada Coma hipotiroideo The apathy and lethargy that often accompany hypothyroidism often delay its diagnosis, so that the perioperative period may be the first place to spot many such hypothyroid patients ANESTHESIA AND ANALGESIA Vol 61, No 4

Hipotiroidismo Post induccion anestesia general los niveles de T3 total disminuyen y, continuan bajos por al menos 24 horas Sistema CV Nivel catecolaminas normal Funcion receptor B adreneregico deprimida Predominio efecto alfa Funcion cardiaca deprimida (inotropismo y cronotropismo) con aumento de la RVS Eje RAA excreta sodio hiponatremia y deplecion volumen vascular The pulmonary system is affected as there may be depressed responses to hypercarbia and hypoxemia58 and, in more severe cases, decreased lung diffusion capacity. Anesthesiology Clin 27 (2009) 687–703

Hipotiroideo Quirurgico Bien controlado con tratamiento Vigilar delirio, ileo prolongado, infeccion sin fiebre, coma mixedematoso Preoperatorio Minimizar sedacion Hipotiroideo leve a moderado No existe aumento desproporcionado riesgo Permeabilidad de la VA POP Reposicion LEV incluyendo soluciones glucosadas There is little to do with the first group other than be aware of their thyroid replacement dosing and be hyperacute to signs and symptoms of worsening hypothyroidism postoperatively including delirium, prolonged ileus, infection without fever, and myxedema coma. Anesthesiology Clin 27 (2009) 687–703

Hipotiroideo Quirurgico Hipotiroideo severo Disminucion de status mental, efusion pericardica y falla cardiaca Levotiroxina Intravenosa (200–500mg en 30 minutos) y continuar 50 a 100 mg IV diaria Suele cursar con insuficiencia adrenal Anesthesiology Clin 27 (2009) 687–703

Coma Mixedematoso Raro Usualmente postoperatorio Injuria adicional Infeccion Exposicion al frio Sedantes / analgesicos Mortalidad 80% Normotermia resulta en vasodilatacion lo cual puede causar colapso cardiovascular Although maintenance of normothermia is tempting, the resulting vasodilatation may cause cardiovascular collapse in someone with intravascular volume depletion, cardiac insufficiency, and pericardial effusion/tamponade; normothermia should be performed extremely carefully, if at all Anesthesiology Clin 27 (2009) 687–703

m www.themegallery.com duration of treatment, thyroid function tests, A. Determine the severity of hypothyroidism. Look for signs and symptoms of hypometabolism. Review medications, affects many organ systems. Tongue enlargement, goiter, and other pertinent study results. Hypothyroidism duration of treatment, thyroid function tests, with airway control. Hypoxic ventilatory drive may and laryngeal myxedema (hoarseness) may interfere depression, cardiomegaly, CHF, and pericardial and at risk for cardiac dysfunction, including myocardial be depressed and sleep apnea may occur. Patients are pleural effusions. ECG abnormalities have been and renal function may delay drug elimination. The gastric emptying may be slow. Impaired hepatic reported.2 GI dysfunction (decreased motility) is common; Mild anemia is common and platelet and coagulation renin-angiotensin-aldosterone system is depressed. disease has been reported.2 If the patient has adequately most consistent finding and acquired von Willebrand’s abnormalities are possible; decreased factor VIII is the treated or mild untreated disease, proceed with corticosteroids because of an increased incidence of medications preoperatively. Consider treatment with the planned surgical procedure.3 Administer thyroid stress.1 Choose an anesthetic technique with attention adrenocortical insufficiency and reduced response to Balance the need for thyroid hormone replacement coronary artery disease (CAD) present special problems. to potential complications. Hypothyroid patients with against the risk of ischemia and myocardial until thyroid function is normalized. If coronary B. If the patient has overt disease, postpone elective surgery infarction (MI). replacement might be omitted.2 revascularization is planned, preoperative thyroid 500 μg; T3, 10 to 50 μg) and corticosteroids while administer parenteral T4 or T3 (T4, 100 to C. For emergencies in patients with overt hypothyroidism, taking supportive measures and monitoring the great. The full effect of this treatment is seen in 36 to risk of MI in acutely treated patients with CAD is patient for dysrhythmias and ischemic changes.3 The drugs that depress respiratory function (sedatives, 72 hours. Premedicate patients minimally, if at all; Place an arterial catheter to monitor ABGs, electolytes, failure.2,4 Monitor core temperature, ECG, and BP. opioids, or general anesthetics) can precipitate respiratory and serum glucose. Insert a CVP or pulmonary artery warm fluids and inhaled gases. Hypothyroid patients patients with CAD or CHF. Use a heating blanket and (PA) catheter for major surgical procedures and in to environmental hypothermia. cannot readily increase core temperature in response used sparingly.1 If general anesthesia is necessary, anesthetic doses are minimized and sedatives are D. Regional blocks provide excellent anesthesia if local intubate the trachea (delayed gastric emptying). to hypotension. Thiobarbiturates may have medications.2 Potent inhalational agents contribute Hypothyroid patients are more susceptible to anesthetic and ventilation and avoid hyperventilation antithyroid properties.2 Ensure adequate oxygenation postoperative ventilatory support and ICU care. E. Postoperative ventilatory failure can occur; consider (decreased carbon dioxide production). mortality. It may be precipitated by surgery, infection, Myxedema coma is a rare complication with a high hypoglycemia, hypothermia, hypoventilation, in patients with stupor, seizures, coma, hyponatremia, sedative, drugs, or trauma. Consider this diagnosis with supportive measures used in managing and heart failure. To treat, initiate IV thyroxine therapy overt disease.5 www.themegallery.com

Hipertiroidismo Etiologia multiple Enfermedad de Graves mas comun Auto Ac receptor TSH = ↑ Hormonas Tiroideas Asociado al embarazo 5% 3 a 6 meses post parto. Recurrencia. Tiroiditis Con o sin dolor en el cuello Adenoma tiroideo Coriocarcinoma Adenoma pituitario secretante de TSH Sobredosis L tiroxina Anesthesiology Clin 27 (2009) 687–703

Signos y Síntomas Hipertiroidismo Endocrinol Metab Clin N Am 35 (2006) 663–686

Signos y Síntomas >70 años <50 años Taquicardia Hipertiroidismo >70 años <50 años Taquicardia Intolerancia Calor Hipertiroidismo F. A. ↑Apetito Apatia Sudoracion Perdida Peso Tremor Longnecker, David E. Anesthesiology In the elderly (older than age 70 years), hyperthyroidism may be difficult to recognize because the hyperkinetic picture is often absent. 12 Also in the elderly, apathy, tachycardia, weight loss, anorexia, and atrial fibrillation are more frequent, whereas in patients younger than age 50 years, heat intolerance, increased appetite, sweating, tremor, hyperreflexia, goiter, and polydipsia are more prevalent.13,14 Anorexia Hiperreflexia Polidipsia Longnecker, David E. Anesthesiology

Surgery in the Patient with Endocrine Dysfunction Benjamin A Surgery in the Patient with Endocrine Dysfunction Benjamin A. Kohl, MDa,*, Stanley Schwartz, MDb Cardiovascular effects of thyroid hormone. (Reprinted from Klein I. Thyroid disease and the heart. Circulation 2007;116:1725; with permission.) Anesthesiology Clin 27 (2009) 687–703

Perioperative management of the thyrotoxic patient Roy W Perioperative management of the thyrotoxic patient Roy W. Langley, MDa,b,*, Henry B. Burch, MD Adapted from Burch HB, Wartofsky L. Life-threatening thyrotoxicosis. Thyroid storm. Endocrinol Metab Clin N Am 1993;22:263–77; with permission Endocrinol Metab Clin N Am 32 (2003) 519–534 In supraphysiologic doses, iodine acts to decrease the synthesis of new thyroid hormone (the Wolff–Chaikov effect) and to decrease release of preformed hormone from the thyroid [21]. The Wolff–Chaikov effect can be seen within 24 hours of iodine administration and is maximal at approximately 10 days of treatment

Opciones Terapeuticas Hipertiroidismo Yodo Dosis suprafisiologicas ↓sintesis (efecto Wolff–Chaikov) Inicio 24h. Maximo 10 dias de tratamiento SSKI o Lugol (8 mg yodo por gota) Thionamidas PTU, MMI Bloquea organificacion y acople PTU inhibe ademas conversion periferica T4 a T3 Varias semanas a eutiroideo MMI VM larga, 1 dosis dia, mayor eficacia The amount of iodine needed to decrease thyrotoxicosis in the hyperthyroid patient has been estimated to be as little as 6 mg per day [27]. Preoperative treatment doses generally have been higher than this, such as 1 drop of SSKI 3 times daily, or 3 to 5 drops Lugol’s solution three times daily [25]. Endocrinol Metab Clin N Am 32 (2003) 519–534

Opciones Terapeuticas Hipertiroidismo Beta bloqueadores Debe ser usado en todos los pacientes a menos que se contraindique Propanolol a dosis altas bloquea conversion VM corta, dosis multiples Metabolismo acelerado Efecto rapido metoprolol o esmolol IV Atenolol 50 a mas de 200mg dia Propanolol 40 mg a 320 mg dia The amount of iodine needed to decrease thyrotoxicosis in the hyperthyroid patient has been estimated to be as little as 6 mg per day [27]. Preoperative treatment doses generally have been higher than this, such as 1 drop of SSKI 3 times daily, or 3 to 5 drops Lugol’s solution three times daily [25]. Endocrinol Metab Clin N Am 32 (2003) 519–534

Opciones Terapeuticas Hipertiroidismo Medios de contraste oral Acido Iopanoico Impacta produccion y reduce conversion periferica de T4 a T3 Control rapido Iopadate 3gr reduce 50% en 24h. T4 24% en 72h. The amount of iodine needed to decrease thyrotoxicosis in the hyperthyroid patient has been estimated to be as little as 6 mg per day [27]. Preoperative treatment doses generally have been higher than this, such as 1 drop of SSKI 3 times daily, or 3 to 5 drops Lugol’s solution three times daily [25]. Endocrinol Metab Clin N Am 32 (2003) 519–534

Endocrinol Metab Clin N Am 32 (2003) 519–534

Meta Terapeutica Estado eutiroideo Hipertiroidismo Estado eutiroideo Clinico y bioquimico Es comun que la TSH continue suprimida a pesar de valores normales de T3 y T4 No contraindica cirugia The amount of iodine needed to decrease thyrotoxicosis in the hyperthyroid patient has been estimated to be as little as 6 mg per day [27]. Preoperative treatment doses generally have been higher than this, such as 1 drop of SSKI 3 times daily, or 3 to 5 drops Lugol’s solution three times daily [25]. Endocrinol Metab Clin N Am 32 (2003) 519–534

Manejo Anestesico Premedicacion Evite anticolinergicos Hipertiroidismo Premedicacion Barbiturico, BDZ, narcotico Evite anticolinergicos Monitoria individualizada No hay incrementos significativos en requerimientos anestesicos (MAC) Buena profundidad anestesica Evite drogas que estimulen SNS Ketamina, pancuronio, atropina, efedrina, epinefrina) Tiopental disminuye conversion de T4 a T3 The amount of iodine needed to decrease thyrotoxicosis in the hyperthyroid patient has been estimated to be as little as 6 mg per day [27]. Preoperative treatment doses generally have been higher than this, such as 1 drop of SSKI 3 times daily, or 3 to 5 drops Lugol’s solution three times daily [25]. Endocrinol Metab Clin N Am 32 (2003) 519–534

Manejo Anestesico Tiopental disminuye conversion de T4 a T3 Hipertiroidismo Tiopental disminuye conversion de T4 a T3 Succinil colina y R. no despolarizantes han sido usados sin complicacion Proteccion ocular Puede usarse cualquier Halogenado Oxido nitroso y opioides son seguros Hipotension Fenilefrina. Evitar epi, norepi y dopa o usar dosis bajas The amount of iodine needed to decrease thyrotoxicosis in the hyperthyroid patient has been estimated to be as little as 6 mg per day [27]. Preoperative treatment doses generally have been higher than this, such as 1 drop of SSKI 3 times daily, or 3 to 5 drops Lugol’s solution three times daily [25]. Endocrinol Metab Clin N Am 32 (2003) 519–534

Complicaciones Tormenta tiroidea Intraoperatorio / 48h post cirugia Mortalidad 10% a 75% Asociado a trauma, infeccion, enfermedad medica y, cirugia Sintomas Hiperpirexia ↑41.1 C Taquicardia Delirio Dx clinico tto empirico Other conditions that should be considered in the differential diagnosis include malignant hyperthermia, neuroleptic malignant syndrome, and pheochromocytoma The most common cause in the perioperative period is infection (sepsis). Blood, urine, and sputum cultures should be obtained, however empiric antibiotics are not recommended.52 Finally, for those patients who are volume depleted, particularly if chronic hyperthyroidism exists, volume resuscitation with the addition of dextrose should be administered to replace depleted glycogen stores.53 Anesthesiology Clin 27 (2009) 687–703

Tormenta Tiroidea Elevacion de la temperatura Taquicardia marcada Caracteristicas Clinicas Elevacion de la temperatura Taquicardia marcada Disfuncion cerebral Disfuncion gastrointestinal Four clinical features are required for the diagnosis of thyroid storm:23,24 (a) Temperature elevation with diaphoresis. Temperatures above 106ºF have been reported. (b) A marked tachycardia that is disproportionate to the temperature elevation. This may manifest as sinus tachycardia, atrial fibrillation, or other supraventricular or ventricular tachycardia. (c) Cerebral dysfunction, which may range from agitation, restlessness, and emotional lability to confusion, psychosis, seizures, and coma. (d) Gastrointestinal disturbance ranging from nausea, vomiting, and diarrhea to intestinal obstruction or acute abdomen. The presence of jaundice is a poor prognostic sign.23,24 The precipitating event varies and may include (most commonly) infection; surgery; treatment with radioactive iodine, or the administration of iodinated contrast dyes; cessation of antithyroid medication; amiodarone; exogenous administration of thyroid hormone; diabetic ketoacidosis; hypoglycemia; congestive heart failure; pulmonary embolism, cerebrovascular accident (CVA); bowel infarction; any acute trauma; toxemia of pregnancy, parturition, and the postpartum state; dental extraction; and even vigorous palpation of the thyroid.23,24 Longnecker, David E. Anesthesiology

Thyrotoxicosis and Thyroid Storm Bindu Nayak, MDa, Kenneth Burman, MDa,b,c,* Scoring system: A score of 45 or greater is highly suggestive of thyroid storm; a score of 25–44 is suggestive of impending storm, and a score below 25 is unlikely to represent thyroid storm. Adapted from Burch HB, Wartofsky L. Life-threatening thyrotoxicosis. Thyroid storm. Endocrinol Metab Clin North Am 1993;22(2):263–77. Endocrinol Metab Clin N Am 35 (2006) 663–686 Endocrinol Metab Clin N Am 35 (2006) 663–686

Tormenta Tiroidea Tratamiento Disminuir la produccion y secrecion de hormona tiroidea Bloquear el efecto periferico de la hormona tiroidea Medidas de soporte Determinar la causa The approach to treatment of thyroid storm is 4-fold20,23–25: 1. Decrease production and secretion of thyroid hormone. 2. Block the peripheral effects of thyroid hormones. 3. Maintain supportive care. Aggressive treatment of fever, temperature elevation, acid–base abnormalities, along with respiratory and cardiovascular support. 4. Determine the underlying cause. Longnecker, David E. Anesthesiology

Hipertiroidismo Cirugia electiva diferir si descompensado Controlado tomar medicamento en la mañana Cirugia de urgencia Acceso a drogas que bloqueen los efectos sistemicos Beta bloqueadores Medicamentos antitiroideos Propiltiouracilo Metimazol Yodo b-Blockers not only directly inhibit sympathetic activation but also inhibit the peripheral conversion of T4 to T3 (the most active thyroid hormone). Thionamides, such as propylthiouracil (PTU) and methimazole, are actively transported into the thyroid gland and inhibit further production of hormone. Furthermore, PTU inhibits peripheral conversion of T4 to T3.46 Finally, although necessary for normal thyroid function, inorganic iodide in excess will manifest an antithyroid action known as the Wolff-Chaikoff effect. Anesthesiology Clin 27 (2009) 687–703

Hipertiroidismo Enfermedad de Graves es la forma mas comun Catecolaminas normal Sintomas leves a extremos Tratamiento Iodo radiactivo Drogas antitiroideas Tiroidectomia Terapia medica contraindicada Cancer tiroideo SUSAN H. NOORILY, M.D. Decisión Making in Anesthesiology

SUSAN H. NOORILY, M.D. Decisión Making in Anesthesiology state. Cardiovascular effects include tachycardia, looking for signs and symptoms of a hypermetabolic A. Determine whether hyperthyroidism is controlled by medications, and duration of treatment. Radioablation Review thyroid function tests, other pertinent studies, hypertension, arrhythmia, angina, and heart failure. United States. Thionamides, such as propylthiouracil is the most common therapy for Graves’ disease in the render a patient euthyroid. Iodine is often added to drugs for preoperative preparation but take weeks to (PTU) and methimazole (MMI), are the preferred provide symptomatic relief as well as cardiac protection thionamide treatment. Beta-blockers reduce HR and there is a goiter, review the chest x-ray (CXR) and metabolism and do not prevent thyroid storm.1 If but do not affect thyroxine production or iodine the amount of tracheal compression. If the goiter is other scans to determine the extent of the mass and is abnormal; only emergent procedures preclude B. Avoid elective surgical procedures if thyroid function large, there is a risk of airway obstruction. 1 to 3 months of treatment). Once euthyroid, the waiting for a euthyroid state (which usually requires triiodothyronine (T3); this should not delay surgery. despite normal levels of thyroxine (T4) and thyroid-stimulating hormone (TSH) may remain suppressed administer a combination of beta-blocker, Rapid preparation may be required for emergent procedures: 1 Wait for 2 to 3 hours after giving the thionamide (contains iodine and blocks release of thyroid hormone). corticosteroid, thionamide, iodine, and iopanoic acid patients require special consideration. Patients undergoing before administering iodines. Pregnant thyroid storm.2 may be hyperthyroid and are at risk for developing emergent evacuation of hydatidiform mole is poorly controlled, place an arterial line blockade (watch for thyrotoxic myopathy). If hyperthyroidism C. Monitor ECG, BP, temperature, and neuromuscular cool fluids available. Titrate beta-blocker to an HR PA pressure if indicated. Have a cooling blanket and for BP monitoring and ABG analysis. Monitor CVP or can precipitate congestive heart failure (CHF), bronchospasm, < 90, but be aware that overzealous beta-blockade D. If the patient is euthyroid, choose any appropriate corticosteroids because adrenal reserves may be low. and hypoglycemia in diabetics. Consider of hyperthyroidism (e.g., goiter, heat intolerance, and anesthetic technique with attention to manifestations Graves’ disease can be done under local anesthesia endoscopic orbital decompression for eye disease). In the absence of coagulation abnormalities, (e.g., cervical plexus blocks or field block) has been to allow monitoring of vision.3 Regional anesthesia Experimental evidence indicates that hyperthyroid in certain patients with poor cardiac function.4,5 used successfully for thyroid surgery and may be useful (MAC) is not affected. Increased doses of IV anesthetics extent than normal. Minimum alveolar concentration animals metabolize inhaled anesthetics to a greater anticholinergics, hyperthermia, hypercarbia, and consider deep general anesthesia. Avoid may be required.6 For poorly controlled hyperthyroidism, Complications of thyroid surgery include postoperative drugs that stimulate the sympathetic nervous system. E. Thyroid storm is rare but is a life-threatening occurrence nerve injuries, and hypoparathyroidism.6 hemorrhage with airway compromise, laryngeal avoid a high mortality rate.7 It may be associated with that must be recognized and treated early to occur postoperatively, so consider ICU admission. infection, trauma, or withdrawal from treatment. It may severe intercurrent illness or precipitated by surgery, tachycardia, heart failure, and dehydration. Treat Signs and symptoms include fever, restlessness, agitation, (fluid therapy, cooling blankets, acetaminophen, iodine, corticosteroids, and supportive measures thyroid storm with thionamides; follow with betablockers, hyperthermia (MH) and due to mistaken diagnosis, has causes. Thyroid storm can mimic malignant or sedation), or plasmapheresis.1 Treat underlying precipitating been successfully managed with dantrolene.8 SUSAN H. NOORILY, M.D. Decisión Making in Anesthesiology

Gracias! Por su paciencia Dr Raul Fernando Vasquez