1 / 50

OSCE Data interpretation stations

OSCE Data interpretation stations. Dr Cathy Armstrong Consultant Anaesthetist Dec 2014. Objectives. The stations Format Tips Blood tests Patterns to look for examples. Format. Instructions Brief background

mschenck
Download Presentation

OSCE Data interpretation stations

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. OSCE Data interpretation stations Dr Cathy Armstrong Consultant Anaesthetist Dec 2014

  2. Objectives • The stations • Format • Tips • Blood tests • Patterns to look for • examples

  3. Format • Instructions • Brief background • Study data – ‘after 5 minutes the examiner will ask you some questions on diagnosis & initial management’

  4. Format • Data • Blood tests • ECG • CXR • Observations

  5. Format • Questions from examiner • Structured / standardised • ‘what do the blood tests show?’ • ‘what does the CXR show?’ • What is your most likely diagnosis? What is your top differential? • What will your initial management be?

  6. Tips • Use your thinking time wisely • Use succinct language & be confident • Likely to be some normal investigations also • Show reasoning behind your thoughts • Flag up potential dangers

  7. Tips • Differential diagnosis • Start with your top & why • Initial management • Might include oxygen / fluids / nebulisers • Remember management packages – e.g septic 6 • Further detailed history • Other definitive investigations – e.g.echo, CT • Don’t forget SENIOR HELP / INPUT

  8. Investigations

  9. Full Blood Count • Hb • Males 135 – 180g/l • Females 115 – 160 g/l • WCC • 4.0 – 11 x 109/l • Platelets • 150 – 400 x 109/l

  10. Anaemia classification by MCV MCV – mean cell volume (76 – 96 fl) • Normal MCV (Normocytic) • Acute blood loss • Anaemia of chronic disease • Low MCV (microcytic) • Iron deficiency • Thalassaemia • High MCV (Macrocytic) • B12 or folate deficiency

  11. High wcc - neutrophilia • Raised WCC most commonly due to neutrophilia • Neutrophils account for 40 – 75% of WBC • recognise & ingest foreign particles & microorganisms • Causes of neutrophilia • Infection • Trauma • Infarction • Inflammation • Malignancy • Myeloproliferative disease • Physiological (exercise & pregnancy)

  12. Low wcc - neutropenia • Most commonly caused by neutropenia • Causes of neutropenia • Infection • Drugs • Autoimmune • Alcohol • congenital

  13. Thrombocytosis • Reactive • Chronic inflammatory disorders • Malignant disease • Post-haemorrhage • Post-splenectomy • Haemolytic anaemias • Malignant • Essential thrombocythaemia • Polycythaemia rubra vera • myelofibrosis

  14. Thrombocytopenia • Marrow disorders • Hypoplasia – idiopathic, drug-induced • Infiltration • Leukaemia, Myeloma, Carcinoma, Myelofibrosis • B12 / folated deficiency • Increased consumption of platelets • DIC, ITP, viral infections, bacterial infections • Hypersplenism • Lymphoma, liver disease

  15. Urea & electrolytes • Na 135-145 mmol/l • K 3.5 – 5.5 mmol/l • Ur 2.5 – 6.7 mmol/l • Cr 70 – 150 mmol/l

  16. Hyperkalaemia • Mild 5.5 - 6.0 mmol/l • Mod 6.1 – 7.0 mmol/l • Severe > 7.0 mmol/l • Causes • ↑ intake • Food ingestion / supplements • Rapid blood transfusion • Intercompartmental shifts • Trauma / crush injuries • Burns • Acidosis • Decreased excretion • Acute / chronic renal failure • Adrenocortical insufficiency (e.g. Addisons disease) • Medications • Potassium sparing diuretics, digoxin

  17. Hyperkalaemia • ECG changes • Peaked T waves • Prolonged PR interval • Widened QRS • Loss of P wave • Loss of R wave amplitude • Sine wave pattern • Asystole • Management of mod / severe • Treat underlying cause • Calcium gluconate • Insulin dextrose infusion • Nebulised salbutamol • dialysis

  18. Hypokalaemia • Mild 3.0 – 3.5 mmol/l • Mod 2.5 – 3.0 mmol/l • Severe < 2.5 mmol/l • Causes • ↓ intake • Iatrogenic (no K in IV fluids) • Malnutrition • Renal losses • Renal tubular acidosis • Hyperaldosteronism (Conn’s syndrome) • GI losses • Diarrhoea, vomiting • Intercompartmental shifts • insulin • Alkalosis • Medications • Diuretics, β2 agonists

  19. Hypernatraemia • Usually due to water loss in excess of sodium loss • Causes include: • Iatrogenic (too much IV N saline) • Diabetes Insipidus • Primary aldosteronism (Conn’s Syndrome)

  20. Diseases with electrolyte patterns • Addisons disease (Primary adrenocortical insufficiency) • Na K Ca • Cushings syndrome (excess plasma cortisol) • Na K Ca • Conn’s Syndrome (hyperaldosteronism) • Na K

  21. Diseases with electrolyte patterns • Addisons disease (Primary adrenocortical insufficiency) • Na ↓ K ↑ Ca ↑ • Cushings syndrome (excess plasma cortisol) • Na ↑ K ↓ Ca ↓ • Conn’s Syndrome (hyperaldosteronism) • Na ↑ ↔ K ↓

  22. Raised Urea & creatinine • Both raised in renal failure • Alternative causes of a raised urea with relatively normal Cr • Dehydration • GI haemhorrhage • High protein diet

  23. Deciphering between acute & chronic renal failure using blood results • Chronic renal failure • Anaemia of chronic disease • Low calcium • High phosphate

  24. Liver Function tests Non-specific Bilirubin AST (Aspartate transaminase) ALP (Alkaline phophatase) γ – GT (Gamma –glutamyl transpeptidase) Albumin Specific ALT (Alanine aminotransferase)

  25. LFT patterns • Hepatocellular Damage • Large ↑ in ALT with small ↑ in ALP • Biliary obstruction • Small ↑ ALT with large ↑ in ALP & γ -GT

  26. Areas not covered • Clotting studies • Anticoagulant monitoring • CRP • Blood cultures • Specialist tests • E.g – vasculitis screens / immunology

  27. Normal ABG Values 7.35 - 7.45 10-12 kPa 4.5 - 6.0 kPa 22 – 26 mmol/l -2 - +2 mmol/l pH PaO2 PaCO2 HCO3 Base Excess IN AIR Many modern gas machines also measure K+ Na+ Cl- SaO2 Hb COHb MetHb Lactate

  28. Expected PO2 on oxygen % oxygen – 10

  29. Examples

  30. Ryan • Ryan is a 17 year old male. He has presented to A&E with a 2 month history of general malaise. Over the past few days he has been vomiting with stomach cramps. • BP 110/70, Apyrexial, RR 39 • Review the investigations provided. You will then be asked questions on diagnosis and initial management.

  31. Ryan

  32. Hb 12.9 (9.0 – 13.0) Wcc 7.0 (4.0 – 11.0) Plt 395 (150-400) Na 139 (135-145) K 4.5 (3.5-5.5) Ur 15.0 (3.3-6.6) Cr 140 (80-120) Blood glucose 35mmol/l ABG on air pH 7.12 (7.35-7.45) PCo2 3.0 (4.5-6.0) PO2 11.0 (10-12 in air) HCO3 17 (22-26) BE -23 (-2- +2) Ryan

  33. Ryan

  34. Jack • Jack is a 77 year old male. He has presented to A&E with a 2 day history of abdominal pain and vomiting. • BP 90/45, T 38.5. RR 30 • Examination of the abdomen reveals a hard abdomen with generalised tenderness and guarding • Review the investigations provided. You will then be asked questions on diagnosis and initial management.

  35. Hb 9.0 (9.0 – 13.0) Wcc 22.3 (4.0 – 11.0) Plt 170 (150-400) Na 139 (135-145) K 4.5 (3.5-5.5) Ur 10.0 (3.3-6.6) Cr 130 (80-120) ABG on air pH 7.22 (7.35-7.45) PCo2 6.1 (4.5-6.0) PO2 7.5 (10-12 in air) HCO3 18 (22-26) BE -10 (-2- +2) Jack

  36. Jack

  37. Jack

  38. Dorothy • Dorothy is a 82 year old female. She has presented to A&E with a 5 day history of productive cough with green sputum and worsening shortness of breath. • BP 93/50, T 38.5. RR 32 • Review the investigations provided. You will then be asked questions on diagnosis and initial management.

  39. Hb 11.0 (9.0 – 13.0) Wcc 21.0 (4.0 – 11.0) Plt 250 (150-400) Na 139 (135-145) K 4.5 (3.5-5.5) Ur 8.0 (3.3-6.6) Cr 90 (80-120) ABG on 60% oxygen pH 7.35 (7.35-7.45) PCo2 4.2 (4.5-6.0) PO2 13 (10-12 in air) HCO3 23 (22-26) BE -3 (-2- +2) Dorothy

  40. Dorothy

  41. Dorothy

  42. CURB 65 • Confusion • Urea – 7.0 or over • RR 30 or over • BP • Systolic 90 or less OR • Diastolic 60 or less • Age 65 or over

  43. Sepsis 6 • Oxygen • Blood cultures • IV antibiotics • Lactate & FBC • IV fluids • Measure UO

  44. Tom • Tom is a 22 year old male. He has presented to A&E with shortness of breath and an audible wheeze • BP 135/90, T 36.5. RR 38 • Review the investigations provided. You will then be asked questions on diagnosis and initial management.

  45. Hb 11.0 (9.0 – 13.0) Wcc 6.0 (4.0 – 11.0) Plt 250 (150-400) Na 139 (135-145) K 4.5 (3.5-5.5) Ur 5.9 (3.3-6.6) Cr 80 (80-120) ABG on 15L oxygen via non-rebreath mask pH 7.32 (7.35-7.45) PCo2 5.9 (4.5-6.0) PO2 9 (10-12 in air) HCO3 23 (22-26) BE -3 (-2- +2) Tom

  46. Tom

  47. Tom

  48. summary • Read instructions carefully • Take time to look at data, formulate a differential diagnosis & initial management plan • Be confident in your approach • Remember senior input

More Related