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1. WEEK 5:... ak k
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2. Thyroid
o Diagnosis & Evaluation ak ak
What labs are used to diagnose?:-TSH - used primarily for screening and diag- nosing
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hypothyroidandformonitoringreplacementtherapyinhypothyroidpatients
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-T4-Usedtomonitorthyroidhormonereplacementtherapyandtoscreenforthyroid
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dysfunction
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-T3 - Useful in the diagnosis of hyperthyroidism;can also be used to monitor hormone
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replacement therapy
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-TSH low ak
-T4 normal
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-T3 is high = hyperthyroidism
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3. Thyroid
o Diagnosis & Evaluation ak ak
Timeframe for re-check of labs after starting levothyroxine?: Recheck TSH 6-8 k
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weeksafterinitiatingtherapyandafteranydosagechange;CheckTSHatleastonce a year
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after serum TSH is stabilized
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4. Thyroid
o Diagnosis & Evaluation ak ak
Signsandsymptomsofhypothyroidism?:Hypothyroidism:Dependonseverity.
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o Mild:subtle and may go unrecognized k
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o Moderate to severe: ak ak
-Faceispale,puffy,andexpressionless. k
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-Skin cold and dry. ak ak ak
-Hair is brittle and hair loss occurs.
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-Slowed Heart rate. ak ak
-Patientmaycomplainoflethargy,fatigue,and k
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-Temperatureislowered&intoleranttocold. k
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-ThyroidEnlargementmayoccurifreducedlevelsofT3 and T4 k
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Mentation may be impaired. ak ak ak
5. Thyroid
o Diagnosis & Evaluation ak ak
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Signs andsymptomsofhyperthyroidism?:o ElevatedHeartrateandstrong, and
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dysrhythmias and angina may develop
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o TheCNSisstimulated,resultingisnervousness,insomnia,rapidthoughtflow,and rapid
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speech, hyperreflexia, tremors
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o Skeletalmusclesmayweakenandatrophy k
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o Metabolic rate is raised, resulting in health and skin that is warm and moist ak ak ak ak ak ak ak ak ak ak ak ak ak
o Feeling Hot + Heat intolerance ak ak ak ak
o Appetit is increased but fails to match metabolic rate resulting in weight loss
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o All of these signs are referred to as thyrotoxicosis
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o Also usually present with exophthalmos - bulging of the eyes
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6. Thyroid
o Treatment
Treatmentofthyroidstorm?:Characterizedbyprofoundhyperthermia(105de- grees k
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or higher), severe tachycardia, restlessness, agitation, and tremor.
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Unconsciousness, coma, hypotension, and heart failure may ensure. These ak ak ak ak ak ak ak ak
symptoms are produced by excessive levels of thyroid hormone Thyroid crisis
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can be life threatening and requires immediate treatment.
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o High doses of potassium iodide or strong iodine solution are given to suppress
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thyroid hormone release.
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o Methimazole is given to suppress thyroid hormone synthesis ak ak ak ak ak ak ak
o A beta blocker is given to reduce heart rate
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o Additionalmeasuresincludesedation,cooling,andgiving ak ak ak ak ak ak
glucocorticoids and IVF
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7. Thyroid
o Treatment
Resultofnottreatinghypothyroidismduringpregnancy?:Canresultinperma- nent
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neuropsychological deficits in the child - decrease child's IQ
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Theeffectofhypothyroidismislimitedlargelyto the firsttrimester,atime during which the
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fetus is unable to produce thyroid hormone of its own
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Someauthoritiescurrentlyrecommendroutinescreeningforhypothyroidismas soon
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as pregnancy is confirmed
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Womenalreadytakingthyroidhormonereplacementwillneedtoincreasedoseby 50% k
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max between weeks 4-8 of gestation and the levels will level out by week 16
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8. Thyroid
o Treatment
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, NR565FinalStudyGuide k
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Medication to treat symptoms of hyperthyroidism (notice this is treating ak ak ak ak ak ak ak ak ak
symptoms and not the hyperthyroidism itself):Methimazole - first line drug of choice
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(not given to women who are pregnant or breastfeeding)
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o Methimazoleblockssynthesisofthyroid hormone. ak ak ak ak ak
1) Preventstheoxidationofiodine,thereforeinhibitingincorporationofiodineinto ak ak ak ak ak ak ak ak ak ak
tyrosine.
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2) prevents iodinated tyrosine from coupling ak ak ak ak
Propylthiouracil-preferredtreatmentforthyroidstorm
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Beta blockers - help with tachycardia experienced with hyperthyroidism
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9. Thyroid
o Treatment
Drug/Food/Supplement interactions with levothyroxine: Absorption of levothy- k
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roxine is reduced by food - it should be taken on an empty stomach in the morning, at least
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30-60 minutes before breakfast
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Drugsthatreduce absorption include:H2 receptorblockers,PPIs, Carafate,Ques- tran,
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Colestid, Maalox/Mylanta, Tums, iron, Mag salts, Xenical
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Drugs that accelerate levothyroxine: Phenytoin, Carbamazepine, rifampin, Sertra-
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line, and phenobarbital
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Patients taking the following drugs may need to increase their dose of levothyroxine: k
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Warfarin and catecholamines
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Levothyroxinecanalsoincreaserequirementsforinsulinanddigoxin ak ak ak ak ak ak ak ak
10. Diabetes
o Howtoconfirmadiagnosispriortobeginningtreatment:Fastingplasma
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glucose >/= 125mg/dl OR
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Random plasma glucose >/= 200mg/dl ak ak ak ak
plus symptoms of diabetes (polyuria, polydipsia, unexplained weight loss) OR Oral
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glucose tolerance test (OGTT): 2-hour plasma glucose >/= 200mg/dl OR HgbA1C pf
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6.5% or greater - (a test that provides an estimate of glycemic control over the previous
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2-3 months) is now considered a standard test as well
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11. Diabetes
o A1C
Generalgoals:TokeepA1Cbelow7% k
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o <8%islessstringentforthosewithhx.Ofseverehypoglycemia,limitedlife
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expectancy, pr advanced microvascular or macrovascular complications
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12. Diabetes
o A1C
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