Endocrine Flashcards
What are precipitating factors for myxedema coma?
Infection, sepsis
Exposure to cold
CVA
Drugs: opioids, amiodarone, lithium, inadequate replacement or non compliance with thyroid hormone
MI
Hyponatraemia
A 74 year old female is brought to ED from her daughters home with delirium. The GP referral letter states she has been lethargic for 1 week, struggling to mobilise, moving very slowly and confused, but cranial nerves, arms and legs have no focal weakness
She usually has a good level of functioning being able to attend to all activities of daily living. She has a background history of hypertension, TIA, previous TRKJR with chronic osteoarthritis of the left knee. She awaits a second knee replacement. Her regular medications are daily candesartan, aspirin and paracetamol and risperidone at night. She was recently commenced on oxycodone for worsening left knee pain.
Her vital signs are:
RR: 10
BP: 90/55
Sats: 90% on RA
Temp: 35
GCS: 13 (E3V4M6)
- List 10 important causes to consider in her differential diagnosis for delirium.
- For each cause list the important investigations required to confirm or exclude the condition
- The patients ECG is shown. List the key findings and provide an interpretation
- What are causes of sinus bradycardia?
- The patients clinical photograph is shown as well as results of thyroid function tests were as follows:
Serum thyroxine 1.2mcg/dl (normal range 5-12)
Triiodothyronine 8.8ng/ml (80-120)
TSH 102 (0.4-4.8)
State 8 criteria for the diagnosis of this condition
- The patients initial ABG and biochemistry are shown. Discuss the key findings with rationale and calculations as required.
pH: 7.11
pO2: 55
pCO2: 88
Na: 118
K: 7
Cl: 90
HCO3: 16
Urea: 20
Creatinine: 200
Glucose: 2.0
Lactate 5.2
Hb: 90
MCV: 110
WCC: 3
Neutrophils: 2
Lymphocytes: 1
- Her CXR and POCUS are shown. State the key findings and provide an interpretation
- List 5 relevant causes in this patient that may cause this
- How would you manage this patient?
1/2.
Hypothyroidism
Encephalitis
MI –> Congestive heart failure
Hyponatraemia
Toxicological causes
-Chronic salicylate toxicity
-Opioids
Adrenal insufficiency - Addisons disease
Subdural hematoma
Hypoglycaemia
Sepsis - pneumonia
CKD
Liver failure
Tests for delirium
-Vital signs: hypoxaemia, hypotension, hypetension, hypothermia/ hyperthermia, pain
-BSL: hyperglycaemia, hypoglycaemia
-Blood gas: hypoxemia, hypercarbia, respiratory alkalosis, metabolic acidosis
-FBC: Anaemia, occult infection, TTP, megaloblastic anaemia
-Sodium, calcium, chloride, bicarbonate, creatinine, magnesium, phosphate, osmolality
-Hypernatraemia, hyponatraemia, uraemia
-Urinalysis: nitrites, leukocytes, ketones
-CXR: occult infection
-Drug levels: digoxin, paracetamol, salicylate
-Tropnin, liver function, ammonia, coagulation studies, B12, folate, ANA
-Myocardial infarction, liver failure, hypothyroid, B12
deficiency, folate deficiency, vasculitis
-CT head: CVA, SOL, ICH
-LP: Meningitis, encephalitis, SAH
-EEG: Non convulsive status epilepticus
-Sinus bradycardia, rate 42
-Electrical alternans
-Small voltage QRS complex voltages
4.
Causes of sinus bradycardia
-Amyloidosis, ACS
-Beta blockers
-Calcium channel blockers
-Digoxin
-Electrolytes, hyperkalaemia
-Fibrosis
-Hypothyroid, Hypothermia
-Infective - myocarditis
-Opioids
-Raised ICP
-Picture: myxedema facies, puffy face, course features
Recognition of myxedema coma
- Patient profile: older woman in winter
- Known hypothyroidism, thyroidectomy scar
- Hypothermia, temp < 36
- AMS - lethargy and confusion to stupor and coma, agitation, psychosis, seizure
- Hypotension - refractory to volume resuscitation and pressors unless thyroid hormone administered
- Shallow respirations with hypercapnia and hypoxia, high risk of respiratory failure
- Sinus bradycardia, long QT, ventricular arrhythmias
- Myxedema facies - puffy eyelids and lips, large tongue, broad nose
- Evidence of severe chronic hypothyroidism - skin, hair, reflexes, bradykinesias, hoarse voice, goiter
- Acute precipitating illness
- Drug toxicity
- Hyponatraemia
Myxedema coma and coexisting adrenal insufficiency
-Acute respiratory acidosis with PaCO2 of 88
-Expected HCO3 = 14-16
-AG = 12 - no metabolic acidosis
-Urea/Cr = 20/0.2 = 100 (consistent with pre renal AKI)
-PF ratio = 55/0.21 = 275
-V/Q mismatch secondary to heart failure
-Macrocytic anaemia secondary to hypothyroidism, B12 or folate deficiency
Notes
-Typical findings in myxedema coma are hyponatraemia (increased ADH) and decreased GFR
-Hyponatraemia leads to AMS and coma
-Increased risk of bleeding due to acquired von willibrand syndrome and decrease in factors V, VII, IX, X
-Anaemia (normocytic or macrocytic)
-Hypoglycaemia (downregulation of metabolism)
-Leukopenia
-
7.
-CXR: Globular shaped heart, increased CTR consistent with cardiomegaly, right sided pleural effusion, reticulonodular opacification on right
-POCUS: Pleural effusion
-Myxedema
-Uraemia
-Acute myocardial infarction
-Aortic dissection
-Malignancy
-Pericarditis
-Radiation
-This patient has a myxedema coma and needs urgent thyroid hormone replacement
-Levothyroxine (T4) 200-400 μg IV bolus OR
Liothyronine (T3) 25-50 μg IV
-Oxygen 1-2L via nasal prongs to maintain sats > 94%
-Small aliquots of IV normal saline 250ml aiming MAP > 65
-Commence low dose noradrenaline 0.05mcg/kg/min
-Prepare for potential pericardiocentesis if develops cardiogenic shock
-50ml of 50% dextrose aiming for BSL > 4
-Hydrocortisone 100mg IV q 8 hours
-3ml of 3% sodium chloride to improve delirium
-If develops ECG changes of hyperkalaemia give calcium gluconate 10ml of 10% IV
-Empiric antibiotics - ceftriaxone 2g IV
-Passive rewarming with blankets aiming temp 36
-Liaise with endocrine and ICU teams for ongoing management
A 70 year old man with a background of diabetes, IHD, hypertension and rheumatoid arthritis presents with confusion over the course of 8 hours; his family have brought him to ED as they are concerned about the abrupt deterioration/ He has no other symptoms other than fatigue and worsening sensorium.
His current medications include
-Empagliflozin
-Metformin
-Prednisone
-Methotrexate
-Infliximab
-Aspirin
-Metoprolol
-GTN spray prn
His vitals in ED are:
-HR: 88
-RR: 28
-Sats: 90% on RA
-BP: 100/66
-Temp: 36
-GCS: 14 (E3V5M6)
-CRT: 4s
-Bedside BSL ‘unrecordable - very high’
- List 6 important conditions you would be concerned about in this man, provide rationale
- Initial VBG and two initial ECG’s are produced. State the findings and provide an interpretation
pH: 7.34
HCO3: 18
PaCO2: 35
Na: 155
K: 4.5
Cl: 90
BSL: 38
Lactate: 5
Ketones: 0.9
ACS
ICH/CVA
HHS
DKA
Mixed HHS/ DKA
Hyperglycaemia secondary to sepsis - UTI
-On empagliflozin
Pancreatitis
Metformin toxicity
Salicylate toxicity
HHS with severe dehydration
AG = 155 - 90 - 18 = 47 (HAGMA) - lactic acidosis
BG = 26 (metabolic alkalosis) - vomiting?
Serum osmolality = 2 x Na + urea + glucose = 310 + urea + 38 = > 348mosm/kg
LAD occlusion
ECG 1: aVL shows terminal TWI in aVL, V1-3, u wave inversion in V3
ECG2: STE in V1, 2, aVL, ST depression in II, III, aVF, V5, V6
Two main problems
HHS and ACS secondary to LAD occlusion
ACS treatment
-Aspirin 300mg, ticagrelor 180mg
-Enoxaparin 1mg/kg subcut
Reverse HHS
-Serum osmolality < 300mosm/kg, UO > 0.5ml/kg/hr, BSL < 15
-NRBM 15L oxygen aiming sats > 94%
-Escalate to CPAP with PEEP of 5-10cmH20 when SBP > 110
-Aim to correct serum osmolality and electrolytes over 72 hours
-Estimated fluid deficit is 100-200ml/kg (8-10L)
-Initially give 1L normal saline over 60 mins followed by 500ml/hr
-Aim to reduce osmolality by 3 to 8 mOsm/kg per hour and titrate rate of fluid replacement accordingly
-If osmolality not reducing switch to 0.45% sodium chloride
-Aim to reduce sodium by < 10mmol/ 24 hours
-Commence insulin infusion at 0.05 units/kg/hr once fluid replacement is adequate - approx. 3 hours
-Aiming to reduce BSL 10-15mmol/ 24h, no more than < 5mmol/hr
-Once BSL < 15 start 5% glucose at 125ml/hr, aim BSL 10-15
Monitor potassium and commence replacement when < 4 at 0.25mmol/kg/hr
Monitor for cerebral oedema - AMS, bradycardia, hypotension
-Treat with 3ml/kg 3% saline
-HOB up 30 degrees
Osmotic demyelination syndrome
19 year old caucasian female with a history of Hashimoto thyroiditis diagnosed several years prior presents to ED after witnessed sudden cardiac arrest. She collapsed at home and was found to be pulseless, her roommate initiated CPR, paramedics arrived and CPR was continued with a return of spontaneous circulation after defibrillation, the patient was intubated and transferred to your ED.
Per family the patient had occasionally complained of fatigue but had unintentionally lost 30kg in the previous year. He only medication was levothyroxine 25mcg daily. An initial CT scan of her head was normal. Subsequent MRI of the brain showed cortical gyriform diffusion restriction consistent with an anoxic brain injury.
On examination she was hypotensive, with SBP in the 70’s and pulse in the 150’s. Temperature was 37.5. She was intubated, had cool extremities, had generalised hyperpigmentation and tanning of her skin creases. Her pupils were dilated 5-7mm and poorly reactive.
Laboratory data showed:
ABG
-pH: 7.2
-PaCO2: 45
-PaO2: 50
-HCO3: 17.1
-Na: 121
-K: 6.1
-Cl: 92
-BSL: 3.0
-Creatinine 110
Cardiac troponins were high and trending up
A urine drug screen was negative
Lactate levels were initially high but normalised quickly with IV hydration
Her BP was consistently low despite being on noradrenaline and 3L of IV fluid in 2 hours
Her bedside echo is produced
- List the main features on her ABG
- List the main features on her echo
- Provide a synthesis of the case with rationale
- What additional investigations should be arranged?
- What additional haemodynamic support is needed?
AG = 11.9 (NAGMA)
Expected CO2 = 33 (respiratory acidosis)
NAGMA, hyponatraemia, hyperkalaemia and hypoglycaemia secondary to adrenal insufficiency
Respiratory acidosis secondary to hypoventilation
- Apical 4C view shows RV:LV ratio > 1
No effusion
-Severe shock resistant to vasopressors secondary to adrenal insufficiency secondary to Addisons disease
-Serum cortisol level
-ACTH
-Renin and aldosterone levels
-Adrenal antibodies
-CT abdomen and pelvis
-Hydrocortisone 200mg IV
-Increase levothyroxine to 50mcg daily
-Vasopressin 2units/hr
-ECMO
