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SURGICAL SURGICAL CONDITIONSCONDITIONS
THYROIDECTOMYTHYROIDECTOMY
ENDOCRINE DYSFUNCTION - ENDOCRINE DYSFUNCTION - MANAGEMENTMANAGEMENT
THYROIDECTOMYTHYROIDECTOMY
TOTAL THYROIDECTOMY – THYROID REPLACEMENT IS REQUIRED
SUBTOTAL THYROIDECTOMY – USE SERUM THYROID LEVEL AS AN INDICATOR
THYROIDECTOMY - MEDICATIONTHYROIDECTOMY - MEDICATION
THYROXINE REPLACEMENTTHYROXINE REPLACEMENT
HALF LIFE OF THYROXINE IS FEW DAYS, THEREFORE CAN WAIT TILL STARTING RX.
DOSE (L-THYROXINE) : 0.15 – 0.2mg dly
THYROIDECTOMY - MEDICATIONTHYROIDECTOMY - MEDICATION
TSHTSH
USED AS SUPPRESSION FOR…
1)NON-TOXIC GOITER
2)OR IF SUBTOTAL THYROIDECTOMY
3)FOR TOTAL THYROIDECTOMY FOR THYROID CA (SELECTED CASES)
DOSE : 0.2 – 0.4mg dly
THYROIDECTOMY - MEDICATIONTHYROIDECTOMY - MEDICATION
PROPANOLOLPROPANOLOL
IF PT WAS GIVEN PRE-OP PROPANOLOL, ADVISABLE TO CONTINUE 2 -3 DAYS POST OP.
THYROIDECTOMY - MEDICATIONTHYROIDECTOMY - MEDICATION
HYPOPARATHYROIDISMHYPOPARATHYROIDISM
Hypoparathyroidism can occur post surgery.
More likely in extensive dissection for diffuse nature or malignancy (esp. radical neck dissection)
THYROIDECTOMY - MEDICATIONTHYROIDECTOMY - MEDICATION
THYROID STORMTHYROID STORM
Can occur as a complication post surgery.
Manage precipitating factors
Reduce synthesis and release of thryoid hormones.
Reduce peripheral conversion of T4 to T3.
MX OVERVIEWMX OVERVIEW
THYROIDECTOMY – THYROID STORMTHYROIDECTOMY – THYROID STORM
SUPPORTIVE MEASURESSUPPORTIVE MEASURES
These pts are hypermetabolic and need more fluids electrolytes and glucose.
Bring down fever (but don’t use salicylates – they diplace thyroid hormones from their binding prots.)
Plasma exchange as last resort – not proven to work
THYROIDECTOMY – THYROID STORMTHYROIDECTOMY – THYROID STORM
B-ADRENERGIC BLOCKERSB-ADRENERGIC BLOCKERS
Antagonises the effect of thyroid hormones.
Decreases the
hypersensitivity to
cathecholamines.
FUNCTIONSFUNCTIONS
THYROIDECTOMY – THYROID STORMTHYROIDECTOMY – THYROID STORM
B-ADRENERGIC BLOCKERSB-ADRENERGIC BLOCKERS
Drug of choice as it also inhibits peripheral conversion of t4 to t3
It promptly treats the tachycardia, fever, hyperkinesis & tremor
PROPANOLOLPROPANOLOL
IV doses of 0.5mg with cardiac monitoring up to 10mgGive more 4-6 hrly
THYROIDECTOMYTHYROIDECTOMY - THYROID STORM - THYROID STORM
B-ADRENERGIC BLOCKERSB-ADRENERGIC BLOCKERS
B1 selective agents not as good – do not inhibit T4 to T3
Use when Propanolol contra-indicated.
OTHER AGENTSOTHER AGENTS
Esmolol 250-500micg/kg bolus followed by 50-100mcg/kg/min.
(Diltiazam also good in reducing pulse rate.)
THYROIDECTOMY - THYROID STORMTHYROIDECTOMY - THYROID STORM
CORTICOSTEROIDSCORTICOSTEROIDS
Given because of the relative deficiency.
Also used beacue they inhibit periph. conversion T4 to T3.
Hydrocortisone 100mg ivi 6hrly or Dexamethasone 5mg ivi 12 hrly
THYROIDECTOMY - THYROID STORMTHYROIDECTOMY - THYROID STORM
THIONAMIDESTHIONAMIDES
PropylthiouracilNo parental form avail. – and in thyrotox, GI absorp is downRapid onsetFunction – blocks iodination of Tyrosine and inhib of periph. Conversion (T4 – T3)Dose: 100mg loading then 100mg 2 hrlyMethimazoleSlower onset, but longer action.Does not inhibit periph. Conversion (T4-T3)Dose: 100mg bolus then 20mg 8hrly
CarbimazoleIt is metabolised to methimazole
For all…..
Transient leukopaenia (20%). Agranulocytosis is rare
THYROIDECTOMY - THYROID STORMTHYROIDECTOMY - THYROID STORM
IODINEIODINE
In large doses, it inhibits synthesis and release of thyroid hormonesGive 1 hr after thioamidesPreps are Lugol’s iodine(oral), potassium iodide, sodium iodideDose: Sodium iodide 1g ivi 12hrly or equiv oral dosesIodine containing contrast media are very good as they are more potent inhibiters of periph conversion.
THYROIDECTOMY - THYROID STORMTHYROIDECTOMY - THYROID STORM
LITHIUM CARBONATELITHIUM CARBONATE
Used for patients allergic to iodine. Similar action
Dose: 500-1500mg dly.
Drug monitoring of Lithium.
THYROIDECTOMY - THYROID STORMTHYROIDECTOMY - THYROID STORM
DIGOXINDIGOXIN
Use if AF or heart failure present.
Larger than normal doses because of the high BMR
THYROIDECTOMY - THYROID STORMTHYROIDECTOMY - THYROID STORM
AMIODARONEAMIODARONE
Controls Arrythmias
Inhibits peripheral conversion of T4 to T3.
THYROIDECTOMY - THYROID STORMTHYROIDECTOMY - THYROID STORM
THYROIDECTOMY – MORE THYROIDECTOMY – MORE COMPLICATIONSCOMPLICATIONS
MYXOEDEMA COMAMYXOEDEMA COMA
Thyroid hormonesT3 best idea. Dose: 20mcg/d.T4 not good because periph. conversion is decreased.SteroidsGiven because these pts have impaired glucocorticoid response to stress., or co-existant adrenal insuff. (Schmidt’s syndrome)Dose: Hydrocortisone 200-300mg/d
SupportiveThese pts have reduced response to hypoxia and hypercarbia, and decreased GCS, so ventilation often required.Warm to treat hypothermiaRx hyponatraemia, hypoglycaemia
PARATHYROIDECTOPARATHYROIDECTOMYMY
PARATHYROIDECTOMYPARATHYROIDECTOMY
INTROINTRO
Adenoma and hyperplasia. Removal of multiple glands usually with hyperplasia.
Transient hypopara. after gland removal.Suppression of normal glands
If hypocalcaemia occurs within the first 12-18 hrs, then it is likely to be severe.
PARATHYROIDECTOMYPARATHYROIDECTOMY
CALCIUM REPLACEMENTCALCIUM REPLACEMENT
Mild hypocalcaemia – just watch
Mild hypocal with tingling of lips, fingers, toes – oral therapy.
Tetany – IVI Calcium
NB – pts on digitalis are more susceptible to arrthmiasVit D is usually withheld for 4 – 6 weeks, unless it is difficult to maintain the Ca.Parathyroids usually recover within this period.
PARATHYROIDECTOMYPARATHYROIDECTOMY
HYPOCALCAEMIA – GENERAL HYPOCALCAEMIA – GENERAL ASPECTSASPECTS
Generally a problem in 70-90% of ICU patients.
IVI calcium…Two forms. Chloride and gluconate.Diff. btw 2 is the amount of elemental ca avail at equiv volumes
Avoid rapid admin – causes nausea, flushing, headache arrythmias.Dose – 100mg bolus, then 1-2mg/kgIf not coming up with IVI replacement – consider Mg deficiencyCalcitrol is usually used for the more chronic conditions.
ADRENALECTOMADRENALECTOMYY
ADRENALECTOMY ADRENALECTOMY
ADRENALECTOMY – ADRENALECTOMY – INDICS.INDICS.
Bilateral adrenalectomy most often done for disseminated breast CA.Old days, done for HPT. Now medical mx is good enoughHyperplastic states from pituitary tumoursNeoplasms
ADRENALECTOMYADRENALECTOMY
MANAGEMENTMANAGEMENT
Treat complications - bleeding, pneumothorax, esp if 12th rib is resected.
Ileus following retroperitoneal dissection.
Treat Adrenocortical Insufficiency…
ADRENALECTOMYADRENALECTOMY
ADRENOCORTICAL INSUFFICIENCYADRENOCORTICAL INSUFFICIENCY
Be aggressive. Start even before blood levels available.
Anticipate who will need – Adrenalectomy, pt’s who are supressed from steroid therapy, pt’s with adrenal or pituatary disease.
Do not replace as a ‘standard’.
ADRENALECTOMYADRENALECTOMY
ADRENOCORTICAL INSUFFICIENCYADRENOCORTICAL INSUFFICIENCY
Start replacement with induction of anaesthesia.
Start with Dexamthasone 10mg IVI, together with ACTH 0.25 ivi (synacthen)Continue steroid replacement with Hydrocortisone 100mgiv 6-8hrly. Taper. Taper then to oral.
Hydrocortisone has sufficient mineralocrticoid component.
ADRENALECTOMYADRENALECTOMY
GENERAL MEASURESGENERAL MEASURES
Avoid opiates and sedativesCorrect electrolyte and glucoseFluid balanceEcg monitoringTreat shockFluids need to be aggressive initially
PHAEOCHROMOCYPHAEOCHROMOCYTOMATOMA
PHAEOCHROMOCYTOMAPHAEOCHROMOCYTOMA
GENERALGENERAL
Tumour of the Adrenal Medulla
No other surgical problems for consideration in the adrenal medulla
PHAEOCHROMOCYTOMAPHAEOCHROMOCYTOMA
PROCEDURES DURING PROCEDURES DURING SURGERYSURGERYPrep for surgery: alpha-adrenergic blocker
as soon as dx madePhenoxybenzamine 10-100mg b.d. for at least 3 d before Sx.Phentolamine (1-5mg) can be used for immed effect if the BP rises during sx Approp. inotropes and volume expanders to be used if BP drops after removal. Propanolol can be used pre, intra, and post op to prevent and Rx cardiac arrythmias. Oral or IVI (10th the oral dose).
PHAEOCHROMOCYTOMAPHAEOCHROMOCYTOMA
POST SURGERYPOST SURGERY
Few days post Sx: urinary Vanillymandelic Acid and Cathecholamines to verify proper removal of tumour.
If bilateral adrenalectomy was done – consider corticosteroid replacement.
PITUITARYPITUITARYSURGERYSURGERY
PITUATARY SURGERYPITUATARY SURGERY
INTROINTRO
ACTH replacement must be given as described
Remember, with pharmacologic doses of steroids, underlying diabetes may be unmasked, and DKA etc must be managed.
PITUATARY SURGERYPITUATARY SURGERY
ADH DEFICIENCYADH DEFICIENCY
This occurs unless the stalk is left intact, there may be no deficiency.
Triphasic response to sx….1)Immed post sx – polyuria and polydipsia –
4 to 5 days2)Intense anti-diuresis for 6 days3)Permanent poyuria and polydipsia (DI)
Phase one is due to damage to hypothalamus tissue and hormone not released.
Phase 2 is due to degeneration of hormone laden stores. Fluid admin during this phase will not induce the usual diuretic response.
PITUATARY SURGERYPITUATARY SURGERY
ADH DEFICIENCYADH DEFICIENCY
During polyuric phase – watch fluid balance and electrolytes carefully.
DDAVP is treatmentrx of choice.
MANAGEMENTMANAGEMENT
Rx with ADH to decrease urine to normal values, withan increasein specific gravity.
NON-NON-SURGICAL SURGICAL
ISSUESISSUES
NON-SURGICAL ISSUESNON-SURGICAL ISSUES
HYPERGLYCAEMIAHYPERGLYCAEMIA
Hyperglycemia is a common metabolic feature of severe stress and is becoming recognized as a harbinger of the severity and outcome of illness.
The effects of counterregulatory hormones and pro-inflammatory cytokines predominate as a cause
Reversing hyperglycemia and insulin resistance reduces mortality
INTROINTRO
NON-SURGICAL ISSUESNON-SURGICAL ISSUES
HYPERGLYCAEMIAHYPERGLYCAEMIA
Trials have shown that aggressive treatment of hyperglycemia has a positive impact on immune recovery and the recovery from an MI
One study: Mortality was decreased by 34% in a surgical ICU by “clamping” the glucose level between 4.4 and 6.1 mmol/L
Insulin may have anti-inflammatory properties – but achieving normoglycaemia more important than insulin dose.
INTRO - CONTINUEDINTRO - CONTINUED
NON-SURGICAL ISSUESNON-SURGICAL ISSUES
HYPERGLYCAEMIAHYPERGLYCAEMIA
BBA’s relieve Stress Hyperglycaemia, thus implicating cathecholamines to the disorder.
Metformin particularly useful in SH. It has antihyperglycemic effects via suppression of glucose production of the liver as well as having antioxidant properties – but beware lactic acidosis
INTRO - CONTINUEDINTRO - CONTINUED
GROWTH GROWTH HORMONEHORMONE
NON-SURGICAL ISSUESNON-SURGICAL ISSUES
GROWTH HORMONEGROWTH HORMONE
Despite aggressive nutritional support, critically ill patients remain catabolic with continued nitrogen loss.
GH supplementation has salutary anabolic effects in stressful conditions, but is poven to increase risk of mortality
GH replacement: If GH low, can be replaced with recombinant GH- appears safe
INTROINTRO
NON-SURGICAL ISSUESNON-SURGICAL ISSUES
GROWTH HORMONEGROWTH HORMONEDELITARIOUS EFFECTSDELITARIOUS EFFECTS
Oedema
Insulin resistance
Exacerbated microvascular injury in the face of sepsis
Hyperglycaemia
Induces hepatic enzymes
HPA HPA INSUFFICIENCINSUFFICIENC
YY
HPA INSUFFICIENCYHPA INSUFFICIENCY
INTROINTRO
Adrenal insufficency occurs in 20% of ICU pts
Induced by sepsis, hypovolaemia, stress, drugs
Both high and low cortisol levels assoc. with poor prognosis.
Higher levels assoc. with higher APACHE and SOFA scores = poorer prognosis
HPA INSUFFICIENCYHPA INSUFFICIENCY
EXAMPLESEXAMPLES
Cortisol > 1200 nmol/l in sepsis and resp failure.
Cortisol > 745 nmol/l in ruptured AAA.
A ‘normal’ level for ICU patients cannot be defined.
Use Synacthen and ACTH test.
HPA INSUFFICIENCYHPA INSUFFICIENCY
CORTISOL SUPPLEMENTATIONCORTISOL SUPPLEMENTATION
Physiological doses of glucocorticoids of 300 mg per day leads to supraphysiological circulating cortisol levels
In a multicentre trial, septic pts given high dose cortisol – higher death rate than placebo group.
HPA INSUFFICIENCYHPA INSUFFICIENCY
CORTISOL SUPPLEMENTATIONCORTISOL SUPPLEMENTATION
Concept of “relative adrenal insufficiency” and “low-dose” (ie, 100 to 300 mg per day) corticosteroid therapy.
Initial trials showed promising trends in subgroups of patients with sepsis.
The beneficial effects were restricted to improvements in hemodynamics and a reduction in the need for vasopressor therapy.
HPA INSUFFICIENCYHPA INSUFFICIENCY
GENERAL CONCEPTSGENERAL CONCEPTS
The beneficial effect of steroids remains unproven, and a conservative approach is more prudent.
Clinician must rely on a clinical assessment of the severity of the stress, (evaluate misleading symptoms) to estimate the adequacy of the measured cortisol.
Clues of adrenal dysfunction, such as unexplained eosinophilia
HPA INSUFFICIENCYHPA INSUFFICIENCY
GENERAL CONCEPTSGENERAL CONCEPTS
Certain conditions - TB, Meningitis, Typhoid fever, and PCP - the use of glucocorticoids appears less controversial
Can be considered in selected high-riskpatients, predominantly in septic shock patients, while awaiting confirmatory results of HPA testing.
Steroid therapy should be stopped if results of HPA testing become available and do not indicate the presence of adrenal insufficiency
THETHE ENDEND