Clinical Conditions to Electrolytes and Acid-base Disorders Flashcards
Diarrhoea
- Metabolic acidosis (pH: Low, HCO3: Low, CO2: normal, CO2 goes low in compensation) with normal anion gap
- Hyperchloraemic metabolic acidosis
- Cl: High (Hyperchloraemia)
- K: Low (Hypokalaemia)
- Mg: Low (Hypomagnesaemia)
-
Na: Low (Hyponatraemia)
-
Hypotonic hyponatraemia + Low ECF volume
- Na <135mmol/L
- Plasma osmolality <275mOsm/L
- Low ECF volume
-
Hypotonic hyponatraemia + Low ECF volume
- Urinary Na <20mmol/L
Ureterosigmoidostomy
Metabolic acidosis with normal anion gap
(hyperchloraemic metabolic acidosis)
Fistula (e.g. pancreatic fistula)
Metabolic acidosis with normal anion gap
(hyperchloraemic metabolic acidosis)
Renal tubular acidosis (RTA)
-
Metabolic acidosis with normal anion gap (All types: mainly 1, 2, 4) > cause
- In type 2 >>> HCO3 is lost from the kidneys
- In type 1, 4 >>> Reduced H+ ion excretion from the kidneys
- Cl: High (hyperchloraemic metabolic acidosis) (All types; mainly 1, 2, 4)
- K: Low (type 1,2,3); High (type 4)
Drug: Acetazolamide
- Metabolic acidosis with normal anion gap
- Cl: High (hyperchloraemic metabolic acidosis)
- K: Low (Hypokalaemia)
- Uric acid: High (Hyperuricaemia)
Drug: Allopurinol
Metabolic acidosis with normal anion gap
(hyperchloraemic metabolic acidosis)
Drug: Benzylpenicillin
Metabolic acidosis with normal anion gap
(hyperchloraemic metabolic acidosis)
Drug: Diclofenac
Metabolic acidosis with normal anion gap
(hyperchloraemic metabolic acidosis)
Ammonium chloride injection
Metabolic acidosis with normal anion gap
(hyperchloraemic metabolic acidosis)
Addison’s disease (Low aldosterone level)
- Metabolic acidosis with normal anion gap (hyperchloraemic metabolic acidosis)
- Cl: High (Hyperchloraemia)
- K: High (hyperkalaemia)
- Na: Low (Hyponatraemia)
- Urinary Na >20mmol/L
- Ca: High (Hypercalcaemia)
- Glucose: Low (Hypoglycaemia)
-
Azotaemia: (Raised Nitrogen products in blood)
- Urea: High
- BUN: High
- Creatinine: High
Lactic acidosis
Metabolic acidosis with raised anion gap
Shock
Metabolic acidosis (Lactic acidosis type A) with raised anion gap
Hypoxia
Metabolic acidosis (Lactic acidosis type A) with raised anion gap
Burns
- Metabolic acidosis (Lactic acidosis type A) with raised anion gap
-
Na: Low (Hyponatraemia)
- Possibly → Fluid sequestration “third space”
-
Hypotonic hyponatraemia + Low ECF volume
- Na <135mmol/L
- Plasma osmolality <275mOsm/L
- Low ECF volume
- Urinary Na <20mmol/L
Metformin
Metabolic acidosis (Lactic acidosis type B) with raised anion gap
FeSO4 (Iron in any form)
Metabolic acidosis (Lactic acidosis type B) with raised anion gap
Ketones (Ketosis, High ketone bodies in blood)
Metabolic acidosis with raised anion gap
DKA
- Metabolic acidosis (ketoacidosis) with raised anion gap
- pH: <7.3
- HCO3 <18mmol/L or <15mmol/L
- Anion gap: Raised
- Glucose: High; >11mmol/L or >13.9mmol/L
- Serum Ketones: High
- Urine ketones: High
- PO4: Low
-
Na: Low (pseudo or true hyponatraemia))
- maybe Hypertonic hyponatraemia (plasma osmolality >290mOsm/L + Na <135mmol/L) (due to severe hyperglycaemia)
-
K: High or normal
- Low (hypokalaemia) in only ‘partially treated DKA’
Alcohol
e.g. Methanol
Ethylene glycol etc.
- Metabolic acidosis with raised anion gap
- Ketones: high
- Mg: Low (Hypomagnesaemia)
- PO4: Low (Hypophosphataemia) (In Alcohol excess)
- Uric acid: High (Hyperuricaemia)
Uraemia (high urea in blood)
Metabolic acidosis with raised anion gap
Renal failure
- Metabolic acidosis with raised anion gap
-
Azotaemia (Raised Nitrogen contents in the blood)
- Urea/Urate: High
- Creatinine: High
- BUN: High
- Uric acid: High
- PO4: High (Hyperphosphataemia)
- K: High (Hyperkalaemia)
-
Na: Low (Hyponatraemia)
- Plasma osmolality <275mOsm/L (hypotonic hyponatraemia) + high ECF volume (hypervolaemia/volume overload >>> oedema); water excess is due to low GFR
- In Diuretic stage of renal failure >>> Urinary Na >20mmol/L
- In ATN of ARF >>> Urinary Na >40mmol/L
- In pre-renal uraemia of ARF >>> Urinary Na <20mmol/L
- Ca: Low (Hypocalcaemia)
- ALP: High
-
Urine osmolarity (in case of ARF):
- >500 in pre-renal uraemia of ARF
- <350 in ATN of ARF (though it has higher urinary Na)
(Above are true for both ARF and CRF; except ATN, Pre-renal uraemia and urine osmolarity section)
Acid poisoning
Metabolic acidosis with raised anion gap
Salicylates poisoning/toxicity
OR Aspirin
Metabolic acidosis with raised anion gap + Respiratory alkalosis
Vomiting
- Metabolic alkalosis
- K: Low (Hypokalaemia)
- Cl: Low (Hypochloraemia)
-
Na: Low (Hyponatraemia)
-
Hypotonic hyponatraemia + Low ECF volume
- Na <135mmol/L
- Plasma osmolality <275mOsm/L
- Low ECF volume
-
Hypotonic hyponatraemia + Low ECF volume
- Urinary Na <20mmol/L
Peptic ulcer >>> pyloric stenosis
If vomiting >>>
- Metabolic alkalosis
- K: Low (Hypokalaemia)
- Cl: Low (Hypochloraemia)
-
Na: Low (Hyponatraemia)Hypotonic hyponatraemia + Low ECF volume
- Na <135mmol/L
- Plasma osmolality <275mOsm/L
- Low ECF volume
- Urinary Na <20mmol/L
Aspiration OR Aspiration pneumonia
- Metabolic alkalosis
- Hypokalaemia (maybe)
- Hypochloraemia (maybe)
Nasogastric suction
- Metabolic alkalosis
- K: Low (Hypokalaemia)
- Aspiration may also have hypochloraemia
(maybe due to vomiting or aspiration)
Diuretics
- Metabolic alkalosis
- Cl: Low (Hypochloraemic alkalosis)
- K: Low (Hypokalaemia)
-
Na: Low (Hyponatraemia)
- Hypotonic hyponatraemia + Low ECF volume
- Urinary Na >20mmol/L
- Serum Na <135mmol/L
- Plasma osmolality : <275mOsm/L
- Low ECF volume
- Mg: Low (Hypomagnesaemia)
- Glucose: High (hyperglycaemia)
(It is common by Loop: furosemide/frusemide & thiazide group of diuretics)
Extra by “Only thiazide diuretics”
- Ca: High (Hypercalcaemia)
- Uric acid: High (Hyperuricaemia = Gout)
Spironolactone: Eplerenone causes >>> K : High (Hyperkalaemia)
Liquorice
- Metabolic alkalosis
- K: Low (Hypokalaemia)
Carbenoxolone
- Metabolic alkalosis
- K: Low (Hypokalaemia)
Primary hyperaldosteronism (or Conn’s syndrome)
- Metabolic alkalosis
- K: Low (Hypokalaemia)
CAH (Congenital Adrenal Hyperplasia)
- Metabolic alkalosis
- K: Low (Hypokalaemia)
Cushing’s syndrome
- Metabolic alkalosis
- K: Low (Hypokalaemia)
Bartter’s syndrome
- Metabolic alkalosis
- K: Low (Hypokalaemia)
- Mg: Low (Hypomagnesaemia)
Hyperglycaemia
-
Na : Low
-
Hypertonic hyponatraemia
- Plasma osmolarity >290mOsm/L (=mOsm/Kg or mmol/L)
- Na <135mmol/L
-
Hypertonic hyponatraemia
- If tt becomes DKA or HHS >>> see their specific electrolyte abnormalitis
Hypertonic solution: Mannitol
-
Na : Low
-
Hypertonic hyponatraemia
- Plasma osmolarity >290mOsm/L (=mOsm/Kg or mmol/L)
- Na <135mmol/L
-
Hypertonic hyponatraemia
- if Mannitol is not hypertonic & used as osmotic diuretic >>> hypotonic hyponatraemia + low ECF volume
Hyperlipidaemia (raised serum volume)
-
Pseudohyponatraemia
- Na conc. : Low (<135mmol/L)
- Isotonic hyponatraemia (plasma osmolality 275 to 290mOsm/L)
‘Taking blood from a drip arm’
-
Pseudohyponatraemia
- Na conc. : Low (<135mmol/L)
- Isotonic hyponatraemia (plasma osmolality 275 to 290mOsm/L)
Use of Na free irrigant solutes in ‘hysterectomy’, ‘TURP’ or other surgical conditions
- Na: Low conc. (<135mmol/L)
-
Isotonic hyponatraemia
- Plasma osmolality: Normal (275 to 290mOsm/L)
CCF (Congestive cardiac failure)
-
Hypotonic hyponatraemia + high ECF volume (hypervolaemia → causes oedema)
- Na : <135mmol/L
- Plasma osmolality : <275mOsm/L
- High ECF volume
- Hyponatraemia occurs due to ‘secondary hypoaldosteronism’
- Urinary Na <20mmol/L
Cirrhosis of Liver
-
Hypotonic hyponatraemia + high ECF volume (hypervolaemia → causes oedema)
- Na : <135mmol/L
- Plasma osmolality : <275mOsm/L
- High ECF volume
- Hyponatraemia occurs due to ‘secondary hypoaldosteronism’
- Urinary Na <20mmol/L
Nephrotic syndrome
Hypotonic hyponatraemia + high ECF volume (→ causes oedema)
- Na : <135mmol/L
- Plasma osmolality : <275mOsm/L
- High ECF volume
Sepsis
-
Hypotonic hyponatraemia + high ECF volume
- Na : <135mmol/L
- Plasma osmolality : <275mOsm/L
- High ECF volume
Anaphylaxis
Hypotonic hyponatraemia + high ECF volume
- Na : <135mmol/L
- Plasma osmolality : <275mOsm/L
- High ECF volume
Pregnancy
Possibly →
Hypotonic hyponatraemia + high ECF volume
- Na : <135mmol/L
- Plasma osmolality : <275mOsm/L
- High ECF volume
Respiratory alkalosis
SIADH (due to its any cause)
-
Hypotonic hyponatraemia + normal ECF volume (euvolaemic)
- Na : <135mmol/L
- Plasma osmolality : <275mOsm/L
- Normal ECF volume
- Urine osmolality >100mOsm/Kg (often >500mmol/Kg)
- Urinary Na >20mmol/L
- ALL the SIADH causes are included in it
Hypothyroidism
-
Hypotonic hyponatraemia + normal ECF volume (euvolaemic)
- Na : <135mmol/L
- Plasma osmolality : <275mOsm/L
- Normal ECF volume
- Urinary Na >20mmol/L
Secondary adrenal insufficiency
(Adrenal insufficiency due to any pituitary cause: surgery, radiation, necrosis etc. or drug-induced >>> Lack of ACTH >>> Lack of cortisol)
- Na can be normal
-
Hypotonic hyponatraemia + normal ECF volume (euvolaemic)
- Na : <135mmol/L
- Plasma osmolality : <275mOsm/L
- Normal ECF volume
- K : Normal
- Glucose: Low (Hypoglycaemia)
Malignancy
-
Hypotonic hyponatraemia + normal ECF volume (euvolaemic)
- Na : <135mmol/L
- Plasma osmolality : <275mOsm/L
- Normal ECF volume
(By SIADH or not by SIADH > both possible > and both have same picture above)
- Ca: High (Hypercalcaemia)
Decreased intake of solutes
- Beer potomania
- Tea-and-Toast diet
-
Hypotonic hyponatraemia + normal ECF volume (euvolaemic)
- Na : <135mmol/L
- Plasma osmolality : <275mOsm/L
- Normal ECF volume
Primary polydipsia
-
Hypotonic hyponatraemia + normal ECF volume (euvolaemic)
- Na : <135mmol/L
- Plasma osmolality : <275mOsm/L
- Normal ECF volume
Cerebral haemorrhage
If cerebral salt wasting >>>
-
Hypotonic hyponatraemia + Low ECF volume (hypovolaemia)
- Na : Low (<135mmol/L)
- Plasma osmolality : <275mOsm/L
- Low ECF volume
Brain surgery
If cerebral salt wasting >>>
-
Hypotonic hyponatraemia + Low ECF volume (hypovolaemia)
- Na : Low (<135mmol/L)
- Plasma osmolality : <275mOsm/L
- Low ECF volume
Brain/Head trauma
If cerebral salt wasting >>>
-
Hypotonic hyponatraemia + Low ECF volume (hypovolaemia)
- Na : Low (<135mmol/L)
- Plasma osmolality : <275mOsm/L
- Low ECF volume
Hypokalaemia (due to any cause) >>> possible effect on other electrolytes (in some cases)
-
Hypotonic hyponatraemia + Low ECF volume ( =hypovolaemia)
- Na : Low (<135mmol/L)
- Plasma osmolality : <275mOsm/L
- Low ECF volume
- Mg: Low (Hypomagnesaemia)
Osmotic diuretics (Mannitol, Urea, Glucose, isosrbide etc) and Osmotic diuresis due to diseases
-
By osmotic diuretics >>> Hypotonic hyponatraemia + Low ECF volume (= hypovolaemia)
- Na <135mmol/L
- Plasma osmolality <275mOsm/L
- Low ECF volume
- By osmotic diuresis (e.g. HHS) >>> Hypernatraemia
Drug: Lithium
- Ca: High (Hypercalcaemia)
- Mg: High (Hypermagnesaemia)
- Na: Low (possibly hyponatraemia)