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Premium member Presentation Transcript LONG CASE PRESENTATIONTHYROID SWELLING : LONG CASE PRESENTATIONTHYROID SWELLING DR.ANIRBAN CHATTOPADHYAY PGT ANESTHESIOLOGY IPGMER (A)PARTICULARS OF THE PATIENT: : (A)PARTICULARS OF THE PATIENT: 1.Name – Purnima Mondal 2.Age- 36years. 3.Sex-Female. 4.Religion-Hindu. 5.Social status-Poor. 6.Occupation-Housewife. 7.Residence-Vill:Pukurkona,P.O:Mithipur,Dist:Murshidabad. (B)CHIEF COMPLAINTS: : (B)CHIEF COMPLAINTS: 1. Swelling in front of neck for last 12 years. 2. Swelling gradually increasing in size for last 18 months. (C)HISTORY OF PRESENT ILLNESS: : (C)HISTORY OF PRESENT ILLNESS: The patient was apparently normal 12yrs back. Then she gradually developed a swelling in the neck. Initially the swelling was small, then it gradually increased in size for last 18 months or so. The swelling was painless. HISTORY OF PRESENT ILLNESS….contd. : HISTORY OF PRESENT ILLNESS….contd. No history of discharge from the swelling, difficulty in swallowing and respiration, hoarseness of voice. No history of loss of appetite, weight loss, weight gain, loose motions, constipation, loss of hair, excessive sweating, palpitation, heat intolerance, irritability, disturbed sleep, tremor in hands,weakness(generalised),double vision, breathlessness on exertion, chest pain, unconciousness and dry skin. No history of hypertension, diabetes mellitus,asthma. (D)HISTORY OF PAST ILLNESS: : (D)HISTORY OF PAST ILLNESS: No significant history. (E) FAMILY HISTIORY: : (E) FAMILY HISTIORY: No history of similar illness in any of the family members. (F)PERSONAL HISTORY: : (F)PERSONAL HISTORY: No history of addiction, allergy to any food or medicines. She is non-vegetarian. Menstrual history –NAD. Bowel and bladder habit –normal. Current medication – tab carbimazole 5 mg thrice daily plus tab propanolol 40 mg qds. PHYSICAL EXAMINATION : PHYSICAL EXAMINATION GENERAL SURVEY Pt. is alert, conscious and co-operative. Build- average, State of nutrition- poor, Decubitus- of choice, Facies- normal, Pallor- mild, Icterus- absent, Cyanosis- absent, Clubbing- absent. GENERAL SURVEY….contd. : GENERAL SURVEY….contd. Pulse- rate-80/min, rhythm-regular, volume-normal, all peripheral pulses are palpable, condition of arterial wall-normal. no radio radial or radio femoral delay Blood pressure-130/86 mm of Hg. GENERAL SURVEY….contd. : GENERAL SURVEY….contd. Respiration- rate-14/min, type-abdominothoracic. Temp-normal, Oedema-absent, Skin-normal. LOCAL EXAMINATION OF THYROID GLAND : LOCAL EXAMINATION OF THYROID GLAND INSPECTION: 1.Situation-swelling on left side of neck which is extending to right side. 2.Shape-ovoid. 3.Size-12cmΧ12cm. 4.Surface-smooth. 5.Edge-defined. 6.Number-one. INSPECTION….contd. : INSPECTION….contd. 7.Pulsation-absent. 8.Movement with deglutition-present. 9.Movement with protrusion of tongue- absent. 10.Skin over the swelling-no oedema, inflammation and discharge. 11.Pembertons sign- negative. PALPATION: : PALPATION: 1.Temperature-not raised, 2.Tenderness-non tender. 3.Size-12cmΧ9cm. 4.Shape-ovoid. 5.Extent- Horizontally-4 cm on the right and 8 cm on the left from midline. Vertically-from the junction of the floor of the mouth and neck to the sternal notch. PALPATION….contd. : PALPATION….contd. 6.Surface-smooth. 7.Edge-defined. 8.Consistency-firm and uniform. 9.Fluctuation-absent. 10.Translucency-not translucent. 11.Reducibility-not reducible. 12.Compressibility-not compressible. PALPATION….contd. : PALPATION….contd. 13.Non pulsatile / no thrill. 14.Fixity to overlying skin-not fixed. 15.Fixity to underlying structures-fixed. 16.Cervical lymph nodes- not palpable. 17. It is possible to get below the swelling. PERCUSSION: : PERCUSSION: Over manubrium sternii- no retrosternal mass. AUSCULTATION: : AUSCULTATION: No bruit. GENERAL EXAMINATION : GENERAL EXAMINATION EYE SIGNS: 1.Lid retraction-absent. 2.Exophthalmos- a)VonGraefe’s sign-absent. b)Joffroy’s sign-absent. c)Stellwag’s sign-absent. d)Moebius sign-absent. e)Dalrympte’s sign-absent. EXAMINATION OF CARDIOVASCULAR SYSTEM: : EXAMINATION OF CARDIOVASCULAR SYSTEM: S1,S2 –audible. No adventitious sounds. No thrill. EXAMINATION OF RESPIRATORY SYSTEM: : EXAMINATION OF RESPIRATORY SYSTEM: Bilateral vesicular breath sound. No adventitious sound. EXAMINATION OF GASTROINTESTINAL SYSTEM: : EXAMINATION OF GASTROINTESTINAL SYSTEM: Abdomen -soft, not distended. -umbilicus central in position. -no palpable lump, organomegaly. -fluid shift-absent. -peristaltic sound-present. EXAMINATION OF NERVOUS SYSTEM: : EXAMINATION OF NERVOUS SYSTEM: No tremor, muscle wasting. Power + Tone upper limb-right-normal. -left-normal. lower limb-right-normal. -left-normal. Deep tendon reflexes-normal. Examination of cranial nerves-normal. AIRWAY EXAMINATION: : AIRWAY EXAMINATION: Mouth opening-3 fingers. No loose tooth/artificial denture. Mallampati- grade II. Thyromental distance-6 fingers. Neck movement-within normal limits. ASA GRADING: : ASA GRADING: ASA GRADE I INVESTIGATIONS : INVESTIGATIONS 1.COMPLETE HAEMOGRAM- Hb-12gm/dl, TLC-9100/cmm, DLC-N60L29MO1E10B00 ESR-24mm/1st hr. 2.BT-1min30secs,CT-3min30secs. 3.Blood group-O+ve. INVESTIGATIONS….contd. : INVESTIGATIONS….contd. 5.Blood sugar-Fasting-89mg/dl. -Post prandial-111mg/dl. 6.Serum urea-16mg/dl. creatinine-0.6mg/dl. INVESTIGATIONS….contd. : INVESTIGATIONS….contd. 7.On 01/05/06 -T3-6.51ng/ml, -T4-24.86mcg/ml, -TSH-0.005mcIU/ml. On 15/09/2008- T3-3.12ng/ml, -T4-13.7mcg/ml, -TSH-0.05mcIU/ml. INVESTIGATIONS….contd. : INVESTIGATIONS….contd. On 13/08/2009-T3-2.60ng/ml, -T4-9.96mcg/ml, -TSH-2.6mcIU/ml. [Normal values in adult- -T3-0.846to2.020ng/ml, -T4-5.130to 14.060mcg/ml, -TSH-0.270to4.200mcIU/ml.] INVESTIGATIONS….contd. : INVESTIGATIONS….contd. 8.Chest X-ray-PA view-normal. 9.Electrocardiogram-normal. 10.USGRight lobe-43Χ16Χ14mm, a focal area of calcification is seen. Left lobe-64Χ51Χ76mm, large nodule with small internal cystic component. 11.FNAC-Thyroid-colloid goitre. 12.CT Scan-Huge solid to cystic swelling on left side of neck extending to the right side. PROVISIONAL DIAGNOSIS: : PROVISIONAL DIAGNOSIS: Thyroid swelling with laboratory evidence of hyperthyroidism without any suggestive clinical features of thyrotoxicosis, controlled at present with medical therapy. Thyroid Gland Considerationsin Anesthesia : Thyroid Gland Considerationsin Anesthesia Cardiovascular manifestations Heat regulation Metabolism Oxygen consumption Thyroid Gland Considerationsin Anesthesia : Thyroid Gland Considerationsin Anesthesia Thyroid hormones directly affect tissue responses to sympathetic stimuli Beta-adrenergic by thyroid hormone Alpha-adrenergic by thyroid hormone HyperthyroidismCauses : HyperthyroidismCauses Graves Disease-most common toxic multinodular goiter TSH hormone secreting pituitary tumors functioning thyroid adenomas overdose of thyroid replacement medication Graves disease : Graves disease Occurs more in female Age 20-40 yrs Autoimmune Classic triad – hyperthyroidism exophthalmos dermopathy : Eye sign in Graves disease Von graffes - upper eye lid lags behid the eye ball when the pt is asked to look downwards Joffroys - no wrinkling of the forehead when asked to look upward Stellwags - infrequent blinking, staring look Mobieus - lack of convergence of eye ball Dalrymple -visibility of upper sclera when pt look forward NOSPECS classification of eye signs N – No sign, no symptoms O – Only sign, no symptoms S - Soft tissue involvement P - Proptosis E – Extraocular involvment C - cornel involvement S - Sight loss : Signs and Symptoms of Thyrotoxicosis (Descending Order of Frequency) SYMPTOMS Hyperactivity, irritability, dysphoria Heat intolerance and sweating Palpitations Fatigue and weakness Weight loss with increased appetite Diarrhea Polyuria Oligomenorrhea, loss of libido SIGNS Tachycardia; atrial fibrillation in the elderly Tremor Goiter Warm, moist skin Muscle weakness, proximal myopathy Lid retraction or lag Gynecomastia : Anesthetic consideration Hypermetabolism of peripheral tissues Increased cardiac work Tachycardia Arrhythmia(commonly atrial),complete heart block Cardiomegaly Thyrotoxic cardiomyopathy High out put cardiac failure Hypercarbia and increased oxygen consumption Decreased vital capacity Increased sympathetic nervous system response Hyperthyroidism : Hyperthyroidism Diagnosis: made by abnormal TFT’s, elevated total and free T4, T3 low TSH, elevated free thyroxine index Medical Treatment consists of drugs that inhibit hormone synthesis (PTU-propylthiouracil, MMI-methimazole), inhibit hormone release (potassium, or sodium iodide) or mask the signs of adrenergic activity (Beta-blocker) While Beta blockade does not affect thyroid gland function, it does decrease the peripheral conversion of T4 to T3. Radioactive iodine and subtotal thyroidectomy are other alternatives to medical therapy Tests of Thyroid Gland FunctionLaboratory Determinations : Tests of Thyroid Gland FunctionLaboratory Determinations Total plasma thyroxine (T4) = Detects > 90% of hyperthyroid patients Resin triiodothyronine uptake (RT3U) Clarifies if T4 changes are due to thyroid dysfunction or alterations in T4 - binding globulin Laboratory Diagnosis: Hyperthyroidism : Laboratory Diagnosis: Hyperthyroidism TSH T4 Free T4 T3 Primary: Subclinical Hyperthyroidism N N N Hyperthyroidism T3 thyrotoxicosis N N Secondary Hyperthyroidism (TSH Secreting Adenoma-Rare!) Pre anesthetic checkup : Pre anesthetic checkup Proper history and clinical features Triad of thyrotoxicosis –hyperactivity, wt loss, tremor AF/CCF/IHD Look for – respiratory difficulty, positional dysponea, dysphagia, SVC syndrome, retrosternal goiter Proper airway assessment Look for other endocrine or autoimmune diseases Associated thrombocytopenia All routine investigations Indirect laryngoscopy CT / MRI as appropriate Pulmonary function test – flow volume loops Informed written consent Subtotal Thyroidectomy Preoperative Measures : Subtotal Thyroidectomy Preoperative Measures For elective sx pt should be made euthyroid by A course of antithyroid drug (PTU or methimazole) 6-8 weeks preoperatively. A low TSH value is not a contraindication for sx as TSH value remain suppressed from prolonged hyperthyroidism in pt who have normal T3/T4. Potassium iodide(SSKI) should be given 7 to 14 days before to reduce size and vascularity and decrease hormonal release. Beta blocker given control heart rate, tremor, anxiety. Avoid anticholinergic drugs Evaluate upper airway (computed tomography) When a patient is ready for elective surgery : When a patient is ready for elective surgery Sleeping pulse rate <90/min Decreased pulse pressure Sinus rhythm, resolution of murmur No tremor/anxiety/palpitation/dysponea/heat intolerance : PREOPERATIVE PREPERATION FOR EMERGENCY SX Antithyroid drug given by NG tube (no iv prep.) even though limited effect if taken for less than 2 weeks. The antithyroid drug should precede iodide by 2-3 hrs. Intravenous beta blocker preferably propanolol (decrease peripheral conversion of T4 toT3) Glucocorticoid (dexamethasone 2mg iv 6 hourly) By these treatment euthyroidism achieved by 5 to 7 days. HyperthyroidismAnesthetic considerations-Preoperative : HyperthyroidismAnesthetic considerations-Preoperative Antithyroid medications and beta-blockers should be continued through the morning of surgery. Avoid anticholinergic medication Benzodiazepines are good choice for pre-operative sedation Careful evaluation of patients airway. In case of large goiter where airway obstruction or difficult intubation is anticipated awake intubation with an armoured tube using fiberoptic bronchoscopy is the safest method. HyperthyroidismAnesthetic considerations-Intraoperative : HyperthyroidismAnesthetic considerations-Intraoperative No controlled study suggest advantages of particular anesthetic drug or technique for hyperthyroid patients, however: Drugs that stimulate sympathetic nervous system should be avoided because of the possibility of large increases in blood pressure and heart rate. Ex. Ketamine. Pancuronium, atropine, ephedrine Thiopental may be induction agent of choice as it possess antithyroid activity at high doses (decreases peripheral conversion of T4 toT3) HyperthyroidismAnesthetic considerations-Intraoperative : HyperthyroidismAnesthetic considerations-Intraoperative Close monitoring of cardiac function and body temperature is required. Need for invasive monitoring depend on sx and pt. Adequate anesthetic depth should be obtained prior to laryngoscopy or surgical stimulation to avoid tachycardia, hypertension, ventricular dysrhythmias Eye protection HyperthyroidismAnesthetic considerations-Intraoperative : HyperthyroidismAnesthetic considerations-Intraoperative Anticipate exaggerated hypotensive response during induction as patient may be hypovolemic Muscle relaxants can be given safely. Patients with autoimmune thyrotoxicosis are associated with an increase risk of myopathies and myasthenia gravis. Reversal with glycopyrrolate instead of atropine Hyperthyroidism does NOT increase MAC requirements, volatile agents can be used safely Intra op hypotension treated by direct acting vasopressure – phenylephrine. Post operative : Post operative Adequate analgesia. Beta blocker and anti thyroid drugs to continue upto 7th day post operatively. HyperthyroidismAnesthetic considerations-Postoperative : HyperthyroidismAnesthetic considerations-Postoperative Thyroid storm is most serious post-op problem Life threatening exacerbation of hyperthyroidism Acute ,rapid increase of thyroid hormone level Characterized by: hyperpyrexia, tachycardia, altered consciousness, extreme anxiety Precipitating factors: infection, trauma, surgery Incidence is 10% in patients hospitalized for thyrotoxicosis Onset is usually 6-24 hours after surgery, but can happen intraoperatively mimicking malignant hyperthermia Unlike MH, not associated with muscle rigidity, elevated CPK, or marked degree or lactic or respiratory acidosis HyperthyroidismAnesthetic considerations-Thyroid Storm : HyperthyroidismAnesthetic considerations-Thyroid Storm Treatment: ABC’s IV Hydration, cool patient IV propanolol (.5mg increments)/esmolol to control heart rate until less than 100. Propylthiouracil 600 mg loading dose followed by 200-300 mg Q6 hours orally or by NG tube Sodium Iodide 1 gram over 12 hours Correction of any precipitating events (infection) Dexamethasone 2 mg every 6 hrs Mortality rate is approximately 20% Anesthetic ConsiderationsSubtotal Thyroidectomy : Anesthetic ConsiderationsSubtotal Thyroidectomy Associated with several complications: Recurrent laryngeal nerve palsy may cause hoarseness if unilateral, or stridor if bilateral Vocal cord function may be evaluated by DL after deep extubation if there is concern Hematoma formation may cause airway compromise. May require immediate opening of neck wound Hypoparathyroidism may result from unintentional removal of parathyroid glands. Hypocalcemia will result within 24-72 hours Pneumothorax Hypothyroidism causes : Hypothyroidism causes Primary Autoimmune hypothyroidism: Hashimoto's thyroiditis, atrophic thyroiditis Iatrogenic: 131I treatment, subtotal or total thyroidectomy, external irradiation of neck for lymphoma or cancer Drugs: iodine excess (including iodine-containing contrast media and amiodarone), lithium, antithyroid drugs, p-aminosalicyclic acid, interferon- and other cytokines, aminoglutethimide Congenital hypothyroidism: absent or ectopic thyroid gland, dyshormonogenesis, TSH-R mutation Iodine deficiency Infiltrative disorders: amyloidosis, sarcoidosis, hemochromatosis, scleroderma, cystinosis, Riedel's thyroiditis Overexpression of type 3 deoiodinase in infantile hemangioma : Transient Silent thyroiditis, including postpartum thyroiditis Subacute thyroiditis Withdrawal of thyroxine treatment in individuals with an intact thyroid After 131I treatment or subtotal thyroidectomy for Graves' disease Secondary Hypopituitarism: tumors, pituitary surgery or irradiation, infiltrative disorders, Sheehan's syndrome, trauma, genetic forms of combined pituitary hormone deficiencies Isolated TSH deficiency or inactivity Bexarotene treatment Hypothalamic disease: tumors, trauma, infiltrative disorders, idiopathic : Symptoms Tiredness, weakness Dry skin Feeling cold Hair loss Difficulty concentrating and poor memory Constipation Weight gain with poor appetite Dyspnea Hoarse voice Menorrhagia (later oligomenorrhea or amenorrhea) Paresthesia Impaired hearing Signs Dry coarse skin; cool peripheral extremities Puffy face, hands, and feet (myxedema) Diffuse alopecia Bradycardia Peripheral edema Delayed tendon reflex relaxation Carpal tunnel syndrome Serous cavity effusions : Anesthetics importance Decreased SV,HR and CO. Increased PVR – diastolic hypertension. Decreased myocardial contractility, enlarged dilated heart. Ventricular dysrhythmia. Pericardial effusion. Depressed baroreceptor function. Decreased maximum breathing capacity and diffusion capacity,weak respiratory muscles. Depressed ventilatory response to hypoxia and hypercarbia. Pleural effusion. Delayed gastric emptying and adynamic ileus. Exaggerated response to NMB. Hypothermia – difficult to treat. : Hematological – anemia, platelet dysfunction, factor VII deficiency. Electrolyte imbalance – hyponatremia. Hypoglycemia. Airway compromise secondary to swollen oral cavity,edematous vocal cords,goiterous enlargement of the gland. Thyroid function test in hypothyroidism : Thyroid function test in hypothyroidism T4 T3 TSH Hypothyroidism (s) Normal Normal Incr.(5-10mU/L) Hypothyroidism (mild) Decr. Decr. Incr.(10-18mU/L) Hypothyroidism(overt) Decr. Decr. Incr.(mean TSH 90mU/L) Hypothyroidism : Hypothyroidism Incidence: 1% of adult population, ten times more prevalent in women Diagnosis: can be confirmed by low free thyroxine levels and elevated TSH (if primary) Medical Treatment: consist of oral replacement HypothyroidismAnesthetic considerations-Preoperative : HypothyroidismAnesthetic considerations-Preoperative Patients with uncorrected severe hypothyroidism (T4<1 ug/dL) or myxedema coma should not undergo elective surgery. Potential for severe cardiovascular instability intraoperatively and myxedema coma. If emergency surgery is necessary, in patients with overt disease or myxedema coma, IV thyroxine and steroid coverage. Euthyroid state is ideal, however, subclinical cases of hypothyroidism has not been shown to significantly increase risk of surgery Continue thyroid replacement mediciness on morning of surgery HypothyroidismAnesthetic considerations-Preoperative : HypothyroidismAnesthetic considerations-Preoperative Airway eval: patients tend to be obese, large tongue, short neck, goiter, swelling of upper airway Pre-op sedation should be administered cautiously if at all, as patients are more prone to drug included respiratory depression from sedatives and narcotics Consider aspiration prophylaxis as many hypothyroid patients have delayed gastric emptying times HypothyroidismAnesthetic considerations-Intraoperative : HypothyroidismAnesthetic considerations-Intraoperative Patients are more sensitive to anesthetic agents because decreased cardiac output, blunted baroreceptor reflexes, and decreased intravascular volume. Invasive monitoring on a per patient basis Ketamine or Etomidate may be induction agents of choice Succinylcholine and non-depolarizing muscle relaxants are generally safe for use. Monitor with peripheral nerve stim. Controlled ventilation is recommended as patients tend to hypoventilate Dextrose in normal saline is recommended to prevent hypoglycemia and hyponatremia. HypothyroidismAnesthetic considerations-Intraoperative : HypothyroidismAnesthetic considerations-Intraoperative Hypothermia occurs quickly and difficult to prevent and treat MAC is essentially unchanged Hematological (anemia, platelet, coag dysfx), electrolyte imbalances, and hypoglycemia is common and require close monitoring intraoperatively Consider co-existed adrenal insufficiency in causes of refractory hypotension Phosphodiesterase inhibitor(milrinone) is effective for treatment of reduced myocardial contractility. HypothyroidismAnesthetic considerations-Intraoperative : HypothyroidismAnesthetic considerations-Intraoperative Hypothermia occurs quickly and difficult to prevent and treat MAC is essentially unchanged Hematological (anemia, platelet, coag dysfx), electrolyte imbalances, and hypoglycemia is common and require close monitoring intraoperatively Intra operative hypotension best treated by ephedrine,epinephrine or dopamine. Consider co-existed adrenal insufficiency in causes of refractory hypotension Myxedema coma : Myxedema coma S/S : Delirium or unconciousness,hypothermia,bradycardia,hypotension,hypoventilation, dilutional hyponatremia. Medical emergency with mortality rate >50%. Triggering events- Infection Cold Trauma CNS depressants HypothyroidismAnesthetic considerations-Myxedema Coma : HypothyroidismAnesthetic considerations-Myxedema Coma Treatment IV thyroxine is indicated (L-thyroxine loading dose 300-500ug, followed by 50ug/day for 24-48hrs) or L-triodothyronine 25-50 ug followed by maintaince. IV hydration with dextrose containing crystalloid, correction of electrolyte abnormalities IV hydrocortisone to supress possible adrenal insuffiency. Support cardiovascular and pulmonary systems as necessary HypothyroidismAnesthetic considerations-Postoperative : HypothyroidismAnesthetic considerations-Postoperative Extubation/Emergence may be delayed secondary to hypothermia, respiratory depression, or slowed drug metabolism Awake extubation, try to maintain normothermia Cautiously administer opioids post-op, consider regional techniques or Ketorolac for post-op pain control Sick euthyroid syndrome : Sick euthyroid syndrome Occurs in critically ill pt with significant nonthyroid illness who demonestrated abnormal TFT. Low level of T3 and T4 and a normal TSH. It may be a physiologic response to stress and can be induced by surgery. No treatment for thyroid. Serum TSH is used to differentiate hypothyroidism from sick euthyroid syndrome. Goiter : Goiter A goiter results from compensatory hypertrophy and hyperplasia of follicular epithelium of thyroid gland. Etiology – deficient intake of iodine ,dietary or pharmacological goitrogen, a defect in hormonal biosynthetic pathway. Goiter pt. is usually euthyroid but hypo or hyper thyroid state may occur. Types – diffuse nontoxic (simple) goiter nontoxic multinodular goiter toxic multinodular goiter hyperfunctioning solitary nodule : Inflammatory swelling – tubercular Hasimoto Dequervains Riedels thyroiditis WHO classification of goiter – Grade 0 - No goiter II - Palpable goiter III - Visible in closed observation IV - Visible from distance Retrosternal goiter : Retrosternal goiter Arises from lower pole of thyroid gland Usually symptomless Diagnosed by CXR S/S – dysponea,dysphagia , cough, engorged neck veins, stridor, recurrent laryngeal nerve palsy CXR – Soft tissue shadow in the superior medistinum Deviation and compression of trachea. Flow volume loops – extrathorasic obstruction : In most cases of simple nontoxic goiter are of unknown etiology and are treated by L-thyroxine 100 ug/day, increasing to 150-200 ug/day with disappearance of goiter by 3-6 months. Sx indicated when medical treatment ineffective, goiter is compromising airway or is cosmetically unacceptable. For anesthesiologists securing airway is of utmost importance. In case of anticipated difficult intubation awake intubation by fibre optic bronchoscope is the safest method. Slide 74: THANK U Thank you You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
anesthetic management in thyroid disorder dranirban Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: Embed: Flash iPad Dynamic Copy Does not support media & animations Automatically changes to Flash or non-Flash embed WordPress Embed Customize Embed URL: Copy Thumbnail: Copy The presentation is successfully added In Your Favorites. Views: 2185 Category: Education License: All Rights Reserved Like it (0) Dislike it (0) Added: January 23, 2011 This Presentation is Public Favorites: 0 Presentation Description this presentation is about the anesthetic management in thyroid disorder specially hypo and hyper thyroid Comments Posting comment... Premium member Presentation Transcript LONG CASE PRESENTATIONTHYROID SWELLING : LONG CASE PRESENTATIONTHYROID SWELLING DR.ANIRBAN CHATTOPADHYAY PGT ANESTHESIOLOGY IPGMER (A)PARTICULARS OF THE PATIENT: : (A)PARTICULARS OF THE PATIENT: 1.Name – Purnima Mondal 2.Age- 36years. 3.Sex-Female. 4.Religion-Hindu. 5.Social status-Poor. 6.Occupation-Housewife. 7.Residence-Vill:Pukurkona,P.O:Mithipur,Dist:Murshidabad. (B)CHIEF COMPLAINTS: : (B)CHIEF COMPLAINTS: 1. Swelling in front of neck for last 12 years. 2. Swelling gradually increasing in size for last 18 months. (C)HISTORY OF PRESENT ILLNESS: : (C)HISTORY OF PRESENT ILLNESS: The patient was apparently normal 12yrs back. Then she gradually developed a swelling in the neck. Initially the swelling was small, then it gradually increased in size for last 18 months or so. The swelling was painless. HISTORY OF PRESENT ILLNESS….contd. : HISTORY OF PRESENT ILLNESS….contd. No history of discharge from the swelling, difficulty in swallowing and respiration, hoarseness of voice. No history of loss of appetite, weight loss, weight gain, loose motions, constipation, loss of hair, excessive sweating, palpitation, heat intolerance, irritability, disturbed sleep, tremor in hands,weakness(generalised),double vision, breathlessness on exertion, chest pain, unconciousness and dry skin. No history of hypertension, diabetes mellitus,asthma. (D)HISTORY OF PAST ILLNESS: : (D)HISTORY OF PAST ILLNESS: No significant history. (E) FAMILY HISTIORY: : (E) FAMILY HISTIORY: No history of similar illness in any of the family members. (F)PERSONAL HISTORY: : (F)PERSONAL HISTORY: No history of addiction, allergy to any food or medicines. She is non-vegetarian. Menstrual history –NAD. Bowel and bladder habit –normal. Current medication – tab carbimazole 5 mg thrice daily plus tab propanolol 40 mg qds. PHYSICAL EXAMINATION : PHYSICAL EXAMINATION GENERAL SURVEY Pt. is alert, conscious and co-operative. Build- average, State of nutrition- poor, Decubitus- of choice, Facies- normal, Pallor- mild, Icterus- absent, Cyanosis- absent, Clubbing- absent. GENERAL SURVEY….contd. : GENERAL SURVEY….contd. Pulse- rate-80/min, rhythm-regular, volume-normal, all peripheral pulses are palpable, condition of arterial wall-normal. no radio radial or radio femoral delay Blood pressure-130/86 mm of Hg. GENERAL SURVEY….contd. : GENERAL SURVEY….contd. Respiration- rate-14/min, type-abdominothoracic. Temp-normal, Oedema-absent, Skin-normal. LOCAL EXAMINATION OF THYROID GLAND : LOCAL EXAMINATION OF THYROID GLAND INSPECTION: 1.Situation-swelling on left side of neck which is extending to right side. 2.Shape-ovoid. 3.Size-12cmΧ12cm. 4.Surface-smooth. 5.Edge-defined. 6.Number-one. INSPECTION….contd. : INSPECTION….contd. 7.Pulsation-absent. 8.Movement with deglutition-present. 9.Movement with protrusion of tongue- absent. 10.Skin over the swelling-no oedema, inflammation and discharge. 11.Pembertons sign- negative. PALPATION: : PALPATION: 1.Temperature-not raised, 2.Tenderness-non tender. 3.Size-12cmΧ9cm. 4.Shape-ovoid. 5.Extent- Horizontally-4 cm on the right and 8 cm on the left from midline. Vertically-from the junction of the floor of the mouth and neck to the sternal notch. PALPATION….contd. : PALPATION….contd. 6.Surface-smooth. 7.Edge-defined. 8.Consistency-firm and uniform. 9.Fluctuation-absent. 10.Translucency-not translucent. 11.Reducibility-not reducible. 12.Compressibility-not compressible. PALPATION….contd. : PALPATION….contd. 13.Non pulsatile / no thrill. 14.Fixity to overlying skin-not fixed. 15.Fixity to underlying structures-fixed. 16.Cervical lymph nodes- not palpable. 17. It is possible to get below the swelling. PERCUSSION: : PERCUSSION: Over manubrium sternii- no retrosternal mass. AUSCULTATION: : AUSCULTATION: No bruit. GENERAL EXAMINATION : GENERAL EXAMINATION EYE SIGNS: 1.Lid retraction-absent. 2.Exophthalmos- a)VonGraefe’s sign-absent. b)Joffroy’s sign-absent. c)Stellwag’s sign-absent. d)Moebius sign-absent. e)Dalrympte’s sign-absent. EXAMINATION OF CARDIOVASCULAR SYSTEM: : EXAMINATION OF CARDIOVASCULAR SYSTEM: S1,S2 –audible. No adventitious sounds. No thrill. EXAMINATION OF RESPIRATORY SYSTEM: : EXAMINATION OF RESPIRATORY SYSTEM: Bilateral vesicular breath sound. No adventitious sound. EXAMINATION OF GASTROINTESTINAL SYSTEM: : EXAMINATION OF GASTROINTESTINAL SYSTEM: Abdomen -soft, not distended. -umbilicus central in position. -no palpable lump, organomegaly. -fluid shift-absent. -peristaltic sound-present. EXAMINATION OF NERVOUS SYSTEM: : EXAMINATION OF NERVOUS SYSTEM: No tremor, muscle wasting. Power + Tone upper limb-right-normal. -left-normal. lower limb-right-normal. -left-normal. Deep tendon reflexes-normal. Examination of cranial nerves-normal. AIRWAY EXAMINATION: : AIRWAY EXAMINATION: Mouth opening-3 fingers. No loose tooth/artificial denture. Mallampati- grade II. Thyromental distance-6 fingers. Neck movement-within normal limits. ASA GRADING: : ASA GRADING: ASA GRADE I INVESTIGATIONS : INVESTIGATIONS 1.COMPLETE HAEMOGRAM- Hb-12gm/dl, TLC-9100/cmm, DLC-N60L29MO1E10B00 ESR-24mm/1st hr. 2.BT-1min30secs,CT-3min30secs. 3.Blood group-O+ve. INVESTIGATIONS….contd. : INVESTIGATIONS….contd. 5.Blood sugar-Fasting-89mg/dl. -Post prandial-111mg/dl. 6.Serum urea-16mg/dl. creatinine-0.6mg/dl. INVESTIGATIONS….contd. : INVESTIGATIONS….contd. 7.On 01/05/06 -T3-6.51ng/ml, -T4-24.86mcg/ml, -TSH-0.005mcIU/ml. On 15/09/2008- T3-3.12ng/ml, -T4-13.7mcg/ml, -TSH-0.05mcIU/ml. INVESTIGATIONS….contd. : INVESTIGATIONS….contd. On 13/08/2009-T3-2.60ng/ml, -T4-9.96mcg/ml, -TSH-2.6mcIU/ml. [Normal values in adult- -T3-0.846to2.020ng/ml, -T4-5.130to 14.060mcg/ml, -TSH-0.270to4.200mcIU/ml.] INVESTIGATIONS….contd. : INVESTIGATIONS….contd. 8.Chest X-ray-PA view-normal. 9.Electrocardiogram-normal. 10.USGRight lobe-43Χ16Χ14mm, a focal area of calcification is seen. Left lobe-64Χ51Χ76mm, large nodule with small internal cystic component. 11.FNAC-Thyroid-colloid goitre. 12.CT Scan-Huge solid to cystic swelling on left side of neck extending to the right side. PROVISIONAL DIAGNOSIS: : PROVISIONAL DIAGNOSIS: Thyroid swelling with laboratory evidence of hyperthyroidism without any suggestive clinical features of thyrotoxicosis, controlled at present with medical therapy. Thyroid Gland Considerationsin Anesthesia : Thyroid Gland Considerationsin Anesthesia Cardiovascular manifestations Heat regulation Metabolism Oxygen consumption Thyroid Gland Considerationsin Anesthesia : Thyroid Gland Considerationsin Anesthesia Thyroid hormones directly affect tissue responses to sympathetic stimuli Beta-adrenergic by thyroid hormone Alpha-adrenergic by thyroid hormone HyperthyroidismCauses : HyperthyroidismCauses Graves Disease-most common toxic multinodular goiter TSH hormone secreting pituitary tumors functioning thyroid adenomas overdose of thyroid replacement medication Graves disease : Graves disease Occurs more in female Age 20-40 yrs Autoimmune Classic triad – hyperthyroidism exophthalmos dermopathy : Eye sign in Graves disease Von graffes - upper eye lid lags behid the eye ball when the pt is asked to look downwards Joffroys - no wrinkling of the forehead when asked to look upward Stellwags - infrequent blinking, staring look Mobieus - lack of convergence of eye ball Dalrymple -visibility of upper sclera when pt look forward NOSPECS classification of eye signs N – No sign, no symptoms O – Only sign, no symptoms S - Soft tissue involvement P - Proptosis E – Extraocular involvment C - cornel involvement S - Sight loss : Signs and Symptoms of Thyrotoxicosis (Descending Order of Frequency) SYMPTOMS Hyperactivity, irritability, dysphoria Heat intolerance and sweating Palpitations Fatigue and weakness Weight loss with increased appetite Diarrhea Polyuria Oligomenorrhea, loss of libido SIGNS Tachycardia; atrial fibrillation in the elderly Tremor Goiter Warm, moist skin Muscle weakness, proximal myopathy Lid retraction or lag Gynecomastia : Anesthetic consideration Hypermetabolism of peripheral tissues Increased cardiac work Tachycardia Arrhythmia(commonly atrial),complete heart block Cardiomegaly Thyrotoxic cardiomyopathy High out put cardiac failure Hypercarbia and increased oxygen consumption Decreased vital capacity Increased sympathetic nervous system response Hyperthyroidism : Hyperthyroidism Diagnosis: made by abnormal TFT’s, elevated total and free T4, T3 low TSH, elevated free thyroxine index Medical Treatment consists of drugs that inhibit hormone synthesis (PTU-propylthiouracil, MMI-methimazole), inhibit hormone release (potassium, or sodium iodide) or mask the signs of adrenergic activity (Beta-blocker) While Beta blockade does not affect thyroid gland function, it does decrease the peripheral conversion of T4 to T3. Radioactive iodine and subtotal thyroidectomy are other alternatives to medical therapy Tests of Thyroid Gland FunctionLaboratory Determinations : Tests of Thyroid Gland FunctionLaboratory Determinations Total plasma thyroxine (T4) = Detects > 90% of hyperthyroid patients Resin triiodothyronine uptake (RT3U) Clarifies if T4 changes are due to thyroid dysfunction or alterations in T4 - binding globulin Laboratory Diagnosis: Hyperthyroidism : Laboratory Diagnosis: Hyperthyroidism TSH T4 Free T4 T3 Primary: Subclinical Hyperthyroidism N N N Hyperthyroidism T3 thyrotoxicosis N N Secondary Hyperthyroidism (TSH Secreting Adenoma-Rare!) Pre anesthetic checkup : Pre anesthetic checkup Proper history and clinical features Triad of thyrotoxicosis –hyperactivity, wt loss, tremor AF/CCF/IHD Look for – respiratory difficulty, positional dysponea, dysphagia, SVC syndrome, retrosternal goiter Proper airway assessment Look for other endocrine or autoimmune diseases Associated thrombocytopenia All routine investigations Indirect laryngoscopy CT / MRI as appropriate Pulmonary function test – flow volume loops Informed written consent Subtotal Thyroidectomy Preoperative Measures : Subtotal Thyroidectomy Preoperative Measures For elective sx pt should be made euthyroid by A course of antithyroid drug (PTU or methimazole) 6-8 weeks preoperatively. A low TSH value is not a contraindication for sx as TSH value remain suppressed from prolonged hyperthyroidism in pt who have normal T3/T4. Potassium iodide(SSKI) should be given 7 to 14 days before to reduce size and vascularity and decrease hormonal release. Beta blocker given control heart rate, tremor, anxiety. Avoid anticholinergic drugs Evaluate upper airway (computed tomography) When a patient is ready for elective surgery : When a patient is ready for elective surgery Sleeping pulse rate <90/min Decreased pulse pressure Sinus rhythm, resolution of murmur No tremor/anxiety/palpitation/dysponea/heat intolerance : PREOPERATIVE PREPERATION FOR EMERGENCY SX Antithyroid drug given by NG tube (no iv prep.) even though limited effect if taken for less than 2 weeks. The antithyroid drug should precede iodide by 2-3 hrs. Intravenous beta blocker preferably propanolol (decrease peripheral conversion of T4 toT3) Glucocorticoid (dexamethasone 2mg iv 6 hourly) By these treatment euthyroidism achieved by 5 to 7 days. HyperthyroidismAnesthetic considerations-Preoperative : HyperthyroidismAnesthetic considerations-Preoperative Antithyroid medications and beta-blockers should be continued through the morning of surgery. Avoid anticholinergic medication Benzodiazepines are good choice for pre-operative sedation Careful evaluation of patients airway. In case of large goiter where airway obstruction or difficult intubation is anticipated awake intubation with an armoured tube using fiberoptic bronchoscopy is the safest method. HyperthyroidismAnesthetic considerations-Intraoperative : HyperthyroidismAnesthetic considerations-Intraoperative No controlled study suggest advantages of particular anesthetic drug or technique for hyperthyroid patients, however: Drugs that stimulate sympathetic nervous system should be avoided because of the possibility of large increases in blood pressure and heart rate. Ex. Ketamine. Pancuronium, atropine, ephedrine Thiopental may be induction agent of choice as it possess antithyroid activity at high doses (decreases peripheral conversion of T4 toT3) HyperthyroidismAnesthetic considerations-Intraoperative : HyperthyroidismAnesthetic considerations-Intraoperative Close monitoring of cardiac function and body temperature is required. Need for invasive monitoring depend on sx and pt. Adequate anesthetic depth should be obtained prior to laryngoscopy or surgical stimulation to avoid tachycardia, hypertension, ventricular dysrhythmias Eye protection HyperthyroidismAnesthetic considerations-Intraoperative : HyperthyroidismAnesthetic considerations-Intraoperative Anticipate exaggerated hypotensive response during induction as patient may be hypovolemic Muscle relaxants can be given safely. Patients with autoimmune thyrotoxicosis are associated with an increase risk of myopathies and myasthenia gravis. Reversal with glycopyrrolate instead of atropine Hyperthyroidism does NOT increase MAC requirements, volatile agents can be used safely Intra op hypotension treated by direct acting vasopressure – phenylephrine. Post operative : Post operative Adequate analgesia. Beta blocker and anti thyroid drugs to continue upto 7th day post operatively. HyperthyroidismAnesthetic considerations-Postoperative : HyperthyroidismAnesthetic considerations-Postoperative Thyroid storm is most serious post-op problem Life threatening exacerbation of hyperthyroidism Acute ,rapid increase of thyroid hormone level Characterized by: hyperpyrexia, tachycardia, altered consciousness, extreme anxiety Precipitating factors: infection, trauma, surgery Incidence is 10% in patients hospitalized for thyrotoxicosis Onset is usually 6-24 hours after surgery, but can happen intraoperatively mimicking malignant hyperthermia Unlike MH, not associated with muscle rigidity, elevated CPK, or marked degree or lactic or respiratory acidosis HyperthyroidismAnesthetic considerations-Thyroid Storm : HyperthyroidismAnesthetic considerations-Thyroid Storm Treatment: ABC’s IV Hydration, cool patient IV propanolol (.5mg increments)/esmolol to control heart rate until less than 100. Propylthiouracil 600 mg loading dose followed by 200-300 mg Q6 hours orally or by NG tube Sodium Iodide 1 gram over 12 hours Correction of any precipitating events (infection) Dexamethasone 2 mg every 6 hrs Mortality rate is approximately 20% Anesthetic ConsiderationsSubtotal Thyroidectomy : Anesthetic ConsiderationsSubtotal Thyroidectomy Associated with several complications: Recurrent laryngeal nerve palsy may cause hoarseness if unilateral, or stridor if bilateral Vocal cord function may be evaluated by DL after deep extubation if there is concern Hematoma formation may cause airway compromise. May require immediate opening of neck wound Hypoparathyroidism may result from unintentional removal of parathyroid glands. Hypocalcemia will result within 24-72 hours Pneumothorax Hypothyroidism causes : Hypothyroidism causes Primary Autoimmune hypothyroidism: Hashimoto's thyroiditis, atrophic thyroiditis Iatrogenic: 131I treatment, subtotal or total thyroidectomy, external irradiation of neck for lymphoma or cancer Drugs: iodine excess (including iodine-containing contrast media and amiodarone), lithium, antithyroid drugs, p-aminosalicyclic acid, interferon- and other cytokines, aminoglutethimide Congenital hypothyroidism: absent or ectopic thyroid gland, dyshormonogenesis, TSH-R mutation Iodine deficiency Infiltrative disorders: amyloidosis, sarcoidosis, hemochromatosis, scleroderma, cystinosis, Riedel's thyroiditis Overexpression of type 3 deoiodinase in infantile hemangioma : Transient Silent thyroiditis, including postpartum thyroiditis Subacute thyroiditis Withdrawal of thyroxine treatment in individuals with an intact thyroid After 131I treatment or subtotal thyroidectomy for Graves' disease Secondary Hypopituitarism: tumors, pituitary surgery or irradiation, infiltrative disorders, Sheehan's syndrome, trauma, genetic forms of combined pituitary hormone deficiencies Isolated TSH deficiency or inactivity Bexarotene treatment Hypothalamic disease: tumors, trauma, infiltrative disorders, idiopathic : Symptoms Tiredness, weakness Dry skin Feeling cold Hair loss Difficulty concentrating and poor memory Constipation Weight gain with poor appetite Dyspnea Hoarse voice Menorrhagia (later oligomenorrhea or amenorrhea) Paresthesia Impaired hearing Signs Dry coarse skin; cool peripheral extremities Puffy face, hands, and feet (myxedema) Diffuse alopecia Bradycardia Peripheral edema Delayed tendon reflex relaxation Carpal tunnel syndrome Serous cavity effusions : Anesthetics importance Decreased SV,HR and CO. Increased PVR – diastolic hypertension. Decreased myocardial contractility, enlarged dilated heart. Ventricular dysrhythmia. Pericardial effusion. Depressed baroreceptor function. Decreased maximum breathing capacity and diffusion capacity,weak respiratory muscles. Depressed ventilatory response to hypoxia and hypercarbia. Pleural effusion. Delayed gastric emptying and adynamic ileus. Exaggerated response to NMB. Hypothermia – difficult to treat. : Hematological – anemia, platelet dysfunction, factor VII deficiency. Electrolyte imbalance – hyponatremia. Hypoglycemia. Airway compromise secondary to swollen oral cavity,edematous vocal cords,goiterous enlargement of the gland. Thyroid function test in hypothyroidism : Thyroid function test in hypothyroidism T4 T3 TSH Hypothyroidism (s) Normal Normal Incr.(5-10mU/L) Hypothyroidism (mild) Decr. Decr. Incr.(10-18mU/L) Hypothyroidism(overt) Decr. Decr. Incr.(mean TSH 90mU/L) Hypothyroidism : Hypothyroidism Incidence: 1% of adult population, ten times more prevalent in women Diagnosis: can be confirmed by low free thyroxine levels and elevated TSH (if primary) Medical Treatment: consist of oral replacement HypothyroidismAnesthetic considerations-Preoperative : HypothyroidismAnesthetic considerations-Preoperative Patients with uncorrected severe hypothyroidism (T4<1 ug/dL) or myxedema coma should not undergo elective surgery. Potential for severe cardiovascular instability intraoperatively and myxedema coma. If emergency surgery is necessary, in patients with overt disease or myxedema coma, IV thyroxine and steroid coverage. Euthyroid state is ideal, however, subclinical cases of hypothyroidism has not been shown to significantly increase risk of surgery Continue thyroid replacement mediciness on morning of surgery HypothyroidismAnesthetic considerations-Preoperative : HypothyroidismAnesthetic considerations-Preoperative Airway eval: patients tend to be obese, large tongue, short neck, goiter, swelling of upper airway Pre-op sedation should be administered cautiously if at all, as patients are more prone to drug included respiratory depression from sedatives and narcotics Consider aspiration prophylaxis as many hypothyroid patients have delayed gastric emptying times HypothyroidismAnesthetic considerations-Intraoperative : HypothyroidismAnesthetic considerations-Intraoperative Patients are more sensitive to anesthetic agents because decreased cardiac output, blunted baroreceptor reflexes, and decreased intravascular volume. Invasive monitoring on a per patient basis Ketamine or Etomidate may be induction agents of choice Succinylcholine and non-depolarizing muscle relaxants are generally safe for use. Monitor with peripheral nerve stim. Controlled ventilation is recommended as patients tend to hypoventilate Dextrose in normal saline is recommended to prevent hypoglycemia and hyponatremia. HypothyroidismAnesthetic considerations-Intraoperative : HypothyroidismAnesthetic considerations-Intraoperative Hypothermia occurs quickly and difficult to prevent and treat MAC is essentially unchanged Hematological (anemia, platelet, coag dysfx), electrolyte imbalances, and hypoglycemia is common and require close monitoring intraoperatively Consider co-existed adrenal insufficiency in causes of refractory hypotension Phosphodiesterase inhibitor(milrinone) is effective for treatment of reduced myocardial contractility. HypothyroidismAnesthetic considerations-Intraoperative : HypothyroidismAnesthetic considerations-Intraoperative Hypothermia occurs quickly and difficult to prevent and treat MAC is essentially unchanged Hematological (anemia, platelet, coag dysfx), electrolyte imbalances, and hypoglycemia is common and require close monitoring intraoperatively Intra operative hypotension best treated by ephedrine,epinephrine or dopamine. Consider co-existed adrenal insufficiency in causes of refractory hypotension Myxedema coma : Myxedema coma S/S : Delirium or unconciousness,hypothermia,bradycardia,hypotension,hypoventilation, dilutional hyponatremia. Medical emergency with mortality rate >50%. Triggering events- Infection Cold Trauma CNS depressants HypothyroidismAnesthetic considerations-Myxedema Coma : HypothyroidismAnesthetic considerations-Myxedema Coma Treatment IV thyroxine is indicated (L-thyroxine loading dose 300-500ug, followed by 50ug/day for 24-48hrs) or L-triodothyronine 25-50 ug followed by maintaince. IV hydration with dextrose containing crystalloid, correction of electrolyte abnormalities IV hydrocortisone to supress possible adrenal insuffiency. Support cardiovascular and pulmonary systems as necessary HypothyroidismAnesthetic considerations-Postoperative : HypothyroidismAnesthetic considerations-Postoperative Extubation/Emergence may be delayed secondary to hypothermia, respiratory depression, or slowed drug metabolism Awake extubation, try to maintain normothermia Cautiously administer opioids post-op, consider regional techniques or Ketorolac for post-op pain control Sick euthyroid syndrome : Sick euthyroid syndrome Occurs in critically ill pt with significant nonthyroid illness who demonestrated abnormal TFT. Low level of T3 and T4 and a normal TSH. It may be a physiologic response to stress and can be induced by surgery. No treatment for thyroid. Serum TSH is used to differentiate hypothyroidism from sick euthyroid syndrome. Goiter : Goiter A goiter results from compensatory hypertrophy and hyperplasia of follicular epithelium of thyroid gland. Etiology – deficient intake of iodine ,dietary or pharmacological goitrogen, a defect in hormonal biosynthetic pathway. Goiter pt. is usually euthyroid but hypo or hyper thyroid state may occur. Types – diffuse nontoxic (simple) goiter nontoxic multinodular goiter toxic multinodular goiter hyperfunctioning solitary nodule : Inflammatory swelling – tubercular Hasimoto Dequervains Riedels thyroiditis WHO classification of goiter – Grade 0 - No goiter II - Palpable goiter III - Visible in closed observation IV - Visible from distance Retrosternal goiter : Retrosternal goiter Arises from lower pole of thyroid gland Usually symptomless Diagnosed by CXR S/S – dysponea,dysphagia , cough, engorged neck veins, stridor, recurrent laryngeal nerve palsy CXR – Soft tissue shadow in the superior medistinum Deviation and compression of trachea. Flow volume loops – extrathorasic obstruction : In most cases of simple nontoxic goiter are of unknown etiology and are treated by L-thyroxine 100 ug/day, increasing to 150-200 ug/day with disappearance of goiter by 3-6 months. Sx indicated when medical treatment ineffective, goiter is compromising airway or is cosmetically unacceptable. For anesthesiologists securing airway is of utmost importance. In case of anticipated difficult intubation awake intubation by fibre optic bronchoscope is the safest method. Slide 74: THANK U Thank you