week 2: pbl 2
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Week 2: PBL 2. Manuel van Deventer. Week 2: PBL 2. - PowerPoint PPT PresentationTRANSCRIPT
Week 2: PBL 2
Manuel van Deventer
Week 2: PBL 2Sosobala Mkhize, a forty year old widower who works as a herbalist, is brought into casualty by his daughter. She says that he had been suffering from a white painful plaque in his mouth for three weeks and that he had just returned from a one week visit to his homeland in search for medicinal herbs. Over the past three days he had not eaten anything and drank only a small amount of fluid, this morning, when she went to take him to his shop, she found him weak and unable to coherently explain what was happening. On admission he was intermittently confused. His blood pressure was found to be low and an IV saline was commenced. On catheterisation of his bladder, very little urine was drained.
• Name: Sosobala Mkhize
• Age: 40
• Marital Status: Widower
• Resident: Umzinto, Kwazulu Natal
Personal Details
• Mr Mkhize is herbalist.
• Since his wife died he has lived with his daughter in a small town in the KwaZulu Natal
• He is independent in all activities.
• Smoked up until the age of 30.
• Drinks 3 or 4 beers per week.
Social History
• No prior history of renal disease
• No previous history of confusion or memory loss
Past Medical History
Current Rx• Possibly self-medicates with herbal
remedies
White Plaque Confused, disoriented Dry mouth, flaccid skin
General Examination
• Blood Pressure: 90/50 lying;
• Pulse rate: 115/minute
• Jugular venous pressure was not raised with the patient lying flat
• CVS examination otherwise normal
CVS
• Bowel sounds present.
• No organomegaly or masses
• No bladder palpable
• Urinalysis: Oliguric
• Catheterisation produced a small amount of urine
Abdomen/UroGenital
InvestigationsFULL BLOOD COUNT & PLATELETS Reference Ranges
White Cell CountRed Cell Count HaemoglobinHaematocritMCVMCHMCHCRed Cell Distribution WidthPlateletsMean Platelet Volume
9.75.912.50.5486.32933.713.615610.2
x 109 / ℓx 1012 / ℓg / dℓℓ / ℓf ℓpgg/dℓ%x 109 / ℓf ℓ
4.00 - 10.00 4.89 - 6.11 14.3 - 18.3 0.43 - 0.55 79.1 - 98.9 27 - 32 32 - 36 11.6 - 14 137 - 373 7.0 - 11.4
Investigations
BIOCHEMISTRY Reference Ranges
Sodium Potassium Chloride Total CO2
Urea Creatinine PhosphateMagnesiumTotal ProteinAlbumin Creatine KinaseGlucoseHIV
1356.61011321.67701.60.811228963.2Pos
mmol / ℓmmol / ℓmmol / ℓmmol / ℓmmol / ℓμmol / ℓmmol / ℓmmol / ℓg/ℓg/ℓU / ℓmmol/l
135 - 147 3.3 - 5.3 99 - 113 18 - 29 2.6 - 7.0 60 - 120 0.8 - 1.4 0.65 - 1.1 60 - 85 35 - 52 25 - 195 4.1 - 5.6
Investigations
URINE BIOCHEMISTRY
Urine VolumeUrine SodiumUrine OsmolalityUrine CreatinineUrinary Myoglobin
3006026020negative
ml/24hmmol / ℓmOsmol/Kgmmol/l
Is this Acute / Chronic
Pre-Renal / Intrinsic
PrerenalUrea/Creat > 75U-Na < 10mmol/lFeNa < 1 %Urine:plasma Osmol
> 1.3
ATN
Urea/Creat < 75
U-Na > 20 mmol/l
FeNa > 1 %
Urine:plasma Osmo < 1.3
• Urea: 21.6 mmol/l
• Creatinine: 770 μmol/l
Urea / Creatinine
Urea 21.6 mmol/l
Creatinine 0.770 mmol/l=
= 28
ATN
UreaProtein
Amino acids
NH3
Cambamoyl phosphatase
Ornithine
Citruline Arginosuccinate
Arginine
Urea cycle
Aspartate
Glomerulus Proximal Tubule
Collecting duct
Distal Tubule
Urea
40-60 %
Creatinine
Creatine Phosphocreatine
Creatinine
Creatine Kinase
ATP ADP
• 60 mmol/l
U-Na
ATN
Fe-Na
FeNa = -------------- X --------------- X 100Urine [Na]
Plasma [Na]
Plasma [Cr]Urine [Cr]
FeNa = -------------- X --------------- X 10060
135
0.770
20
FeNa = 1.7 ATN
• Measured Osmolality– Freezing point depression
• Calculated Osmolality– 2 Na + Urea + Glucose
= 2(135) + 22 + 3
= 295
Osmolality
• U-Osmolality = 260
• = 260/295 = 0.88
• Also U Osmo < 350
Osmolality
ATN
• Increased renal tubular cells and granular casts
U-Microscopy
ATN
Etiology of ATN in this patient
Electrolyte abnormalities
↑ Potassium
Pseudohyperkalaemia
K+ redistribution
K+ retention
Hemolysis
Thrombocytosis
Leukocytosis
Acidosis
Dehydration
Massive tissue Hypoxia
Insulin deficiency
Rhabdomyolysis
↓ K+ excretion
↓ Mineralocorticoids
Addison’sACE inhibitors
K+ sparing diuretics
AmilorideSpironolactone
↑ Potassium
High Anion GapMetabolic Acidosis
Normal Anion GapMetabolic Acidosis
DKA
Acute renal failure
Chronic Renal Failure
↓ mineralocorticoids
Obstructive uropathy
www.aafp.org/afp/20060115/283.html
↓ Potassium
Metabolic AlkalosisNormal Anion GapMetabolic Acidosis
Diuretic therapy
Vomiting
↑ Mineralocorticoids
Diarrhea
RTA
Cations = Anions
Cations - Anions
• Na+ + K+ – Cl- – HCO3-
↑ Unmeasured Anions (Proteins, PO43-, SO4
2-)
↑ Anion Gap
Anion Gap
135 + 6.6 – 101 – 13 = 27.6 ↑
Anion Gap
• M = Methanol toxicity
• U = Ureamia of renal failure
• D = Diabetes Mellitus
• P = Paraldehyde toxicity
• I = Isoniazid / Iron toxicity / Ischemia
• L = Lactic acidosis
• E = Ethylene glycol toxicity
• S = Salicylate toxicity
Anion Gap
http://upload.wikimedia.org/wikipedia/commons/a/a2/Renin-angiotensin-aldosterone_system.png
Na+
K+
H+
↑ Aldosterone
Distal Renal Tubule
Na+
K+
H+
↓ Aldosterone
Distal Renal Tubule
HyponatraemiaMeasure plasma
osmolality
↑ Increased Normal ↓ Decreased
↑ Increased other osmotically
active solutes
Pseudohyponatraemia
Assess ECF volume
Increased Normal Decreased
Renal loss Extrarenal loss
SIADH
H20
1. Clinically Euvolemia2. Plasma Osmolality < 270 mosmol/kg3. Hyponatraemie Na < 130 mmol/l4. Exclude
1. Cardiac2. Renal3. Thyroid4. Adrenal
5. Exclude1. Pituitary surgery2. Medication known to stimulate ADH
6. Urine Osmolality inappropriately high7. U-Na > 20 mmol/l
SIADH
↑ Na+
Hypervolaemia↑↑ Na+
↑ H20
Euvolaemia↑ Na+
Hypovolaemia ↓ H20
Hyperaldosteronism
Cushing’s
Hypertonic Saline
Salt Water Ingestion
Diabetes Insipidus U-Na > 20 U-Na < 10
Osmotic diuresis
Diuretic therapy and ↓ H20 intake
GIT Loss and ↓ H20 intake
• Bicarbonate (HCO3)
TCO2
↓ pH α ↓ HCO3
↓ PCO2
Total Protein
Rx
• Fluid management
• Avoid nephrotoxic drugs
Prevention
• Creatinine Clearance• = U*V
P
= 20 * 300/24/600.77
= 5.4 ml/min
Drug Dosaging
Rx of Complications
• Exchange resins – Kayexalate 30-60g po or pr 6hrly
• Insulin and dextrose
• Dialysis
Hyperkalaemia
Treated when:
•CO2 <15 and pH <7.2
•Bicarbonate
•Dialysis
Acidosis
• Complications of uremia
• What in the history and investigations of this patient suggestive of uremia
• Possible indications for dialysis
Uremia
• Aggressive diuresis if still passing urine
• Dialysis if oligoanuric
• Fluid restriction
Fluid Overload
• Acidosis (severe acidosis resistant to conservative measures)
• Electrolytes (Hyperkalemia resistant to conservative measures)
• Intoxication (alcohols and dialyzable drugs)
• Overload (of fluid)
• Uraemia
Indications for dialysis
Conclusion