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
