Poisoning and Electrolyte Disturbances Flashcards
A 26 year old unconscious man is brought into A&E having been found lying alone on the street with needles next to him. The patient’s GCS = 11, RR = 10, BP = 97/65 mmHg and has pinpoint pupils. This patient likely has:
A. Alcohol toxicity B. Aspirin overdose C. Opiate overdose D. Paracetamol overdose E. Warfarintoxicity
c) Opiate Overdose
Pinpoint Pupils
Respiratory depression
A 26 year old unconscious man is brought into A&E having been found lying alone on the street with needles next to him. The patient’s GCS = 11, RR = 10, BP = 97/65 mmHg and has pinpoint pupils. The most appropriate treatment is: A. IV naltrexone B. IV naloxone C. Mechanical Ventilation D. IV N-Acetyl-Cysteine E. IVSodiumBicarbonate
b) IV Naloxone
Antidote to opiate overdose.
A 25 year old man is rushed to A&E after presenting with vomiting, hyperventilation and ringing in his ears. ABG shows a respiratory alkalosis.
The most likely cause of his presentation is:
A. Alcohol toxicity
B. Aspirin Overdose
C. Opiate Overdose
D. Paracetamol Overdose
E. Warfarintoxicity
b) Aspirin Overdose
Hyperventilation - respiratory alkalosis
Tinnitus
A 70 year old woman undergoes a bowel resection for colorectal cancer. She is well prior to the operation. The operation is successful but two days after the operation she becomes very agitated.
Na = 124 (135-145) K = 3.3 (3.5-5) Ur = 3.1 (3-7) Serum Os. = 265 (275-295) Urine Os. = 150
The most likely cause of the hyponatraemia is: A. Addison’sDisease B. Hypothyroidism C. SIADH D. Use of Diuretics E. Water overload
e) Water Overload
Post operation - being given fluids
A 58 year old woman with metastatic pancreatic cancer attends an oncology clinic. Her husband mentions there has been occasions where she has been confused. Her U&Es show a serum sodium of 116mmol/L. Urine specimen is sent off and confirms a diagnosis of SIADH.
The most appropriate initial treatment is: A. Demeclocycline B. Desmopressin C. Fluid restriction to 1L per day D. IV infusion 5% dextrose E. IV infusion of normal 0.9% saline
c) Fluid Restriction to 1L per day
1st line treatment for SIADH
Demeclocycline (ADH inhibitor) = 2nd line
Clinical Features Aspirin overdose?
Hyperventilation, Tinnitus, Sweating, Vomiting
Opiate overdose features?
Low GCS, Low RR, pinpoint pupils, constipation
Organophasphates can also give pinpoint pupils - but cause diarrhoea + sweating
(TCA depressants = dilated pupils)
Paracetamol overdose features?
Asymptomatic 1st 24hr, then liver failure (vomiting, abdo pain, confusion)
Antidote Opiate overdose?
IV Naloxone
Antidote Paracetamol overdose?
IV N-Acetyl-Cysteine
Management aspirin overdose?
Acute: Fluid Resuscitation
Within 1 hour of known dose: Oral Activated Charcoal (and/or Gastric Lavage if severe)
Moderate poisoning (>500 mg/L) : IV Sodium Bicarbonate infusion =(Alkalinediuresis)
Severe Poisoning (>750mg/L): Haemodialysis
Lithium overdose can cause
Nephrogenic Diabetes Insipidus
A 54 year old with background of high BP presents to GP with a 2 week Hx of diarrhoea following a trip to South East Asia. He was prescribed Tetracycline but his symptoms have persisted. PMHx: Undisplaced skull fracture at age 10.
What is most likely to have caused the hypernatraemia?
Na = 148 (135-145) K = 4.8 (3.5-5) Ur = 13 (3-7) Cr = 112 (70-110)
A. Conn’sSyndrome B. Nephrogenic Diabetes Insipidus C. Cranial Diabetes Insipidus D. Tetracycline E. Dehydration
E) Dehydration
Diarrhoea
Causes hypovolaemic hypernatraemia
Loss water
eg. D+V, sweating, osmotic diuresis (eg hyperglycaemia)
Causes euvolaemic hypernatraemia
Not enough water
eg Inability to access water (elderly people)
Cranial/nephrogenic DI
A 55 year old man admiped for an exacerbation of asthma, is given regular nebulizers alongside his regular anti- hypertensive medication during his stay. A final blood test was done before discharge.
Which drug is most likely to have caused the hypokalaemia?
Na = 137 (135-145) K = 2.9 (3-5.5) Ur = 5.1 (3-7)
A. Ipratropium B. Ramipril C. Salbutamol D. Amlodipine E. Paracetamol
c) Salbutamol
Salbutamol nebs cause K to be taken up into cells.
A 30 year old man presents with increased skin pigmentation, vitiligo, postural hypotension and the following blood results.
What might have caused his hyperkalaemia?
Sodium = 130 (135-145) Potassium = 6.5 (3.5-5.0) Urea = 6.0 (3.0-7.0)
A. ACE-I B. Addison’sDisease C. Conn’s Syndrome D. Rhabdomyolysis E. Spironolactone
b) Addison’s Disease
Pigmentation
Vitiligo (Autoimmune)
Postural Hypotension
Causes Hypokalaemia?
GI: Vomiting Renal Loss: • Diuretics • Primary hyperaldosteronism (Conn’s) Redistribution into cells: • Insulin, Beta-agonists e.g. salbutamol • Alkalosis
Presentation Hypokalaemia?
• Muscle weakness
• Arrhythmias
• Polyuria

In Conn’s, is K up or down?
Low Potassium (High Aldosterone)
Investigations
• Aldosterone : Renin Ratio
• ↑ in Conn’s (↑ Aldosterone)
Management hypokalaemia?
- Treat the underlying cause.
- K+ <3.0mmol/L • IV potassium chloride
Addison’s disease = High or Low K?
High K
Low aldosterone
Causes Hyperkalaemia?
• Addison’s Disease (↓Aldosterone)
- Drugs • e.g. ACE-I, ARBs, Spironolactone
- Renal impairment
• Release from cells: • Rhabdomyolysis (Crush injuries) • Acidosis
Management Hyperkalaemia?
- 10ml 10% Calcium Gluconate
- 50ml 50% dextrose + 10 units of insulin
- Nebulized salbutamol
- Treat underlying cause
A 22 year old student revising hard for her exams begins developing numbness in her hands and twitching. ECG showed a prolonged QT interval
What might have caused his hypocalcaemia?
 Ca = 2.0 (2.2 – 2.6 mmol) PTH = 10.4 (0.8-8.5pmol/ ALP = 190 (30-150u/L) Phosphate = 0.69 (0.8-1.2mmol/ Vitamin D = 41 (60-105 nmol/L) 
A. Primary hyperparathyroidism B. Tertiary hyperparathyroidism C. Osteoporosis D. Renal Failure E. Vitamin D Deficiency
E. Vitamin D Deficiency
A 60 year old woman with lung cancer is electively admitted for her 2nd cycle of palliative chemotherapy. She has known metastasis to her ribs and vertebrae. Since her last cycle of chemotherapy she has felt lethargic and cons%pated. Her corrected calcium levels are 2.95 mmol/ L (2.15-2.65). The most appropriate treatment is:
A. Administer chemotherapy B. IV rehydration alone C. IV rehydration and Pamidronate D. Delay chemotherapy until patient feels beper E. VitaminDSupplements
C. IV rehydration and Pamidronate
Causes Hypercalcaemia
PTH suppressed: Malignancy, Sarcoidosis, Multiple Myeloma (low ALP)
PTH not suppressed: Primary Hyperparathyroidism
Causes Hypocalcaemia
Renal Failure Vit. D deficiency Low PTH (DiGeorge Syndrome)
