OSCE Flashcards
What is acute kidney injury?
-Significant decline in renal function over hours or days manifesting as an abrupt and sustained increase in serum urea and creatinine
What are pre-renal causes of AKI?
- Shock
- Renalvascular compromise eg NSAIDs, ACE I, renal artery stenosis
Give the main causes of renal AKI
- Acute tubulonecrosis caused by ischeamia, hypertension, thrombotic thrombocytopenia purpura
- Interstitial nephritis by drugs (NSAIDs, Abx) and toxins
- Nephritic syndrome
Post Renal causes of AKI
-Stones, neoplasm, stricture, prostate
Describe some possible clinical signs of an AKI
- Oedema
- Altered BP
- Raised JVP
- Postural hypotension
- Raised Urea, creatinine, low urine output, acidosis/hyperkalaemia
What investigations would you do in AKI?
- Bloods -> FBCs, U+Es, LFTs, glucose, Ca, clotting, ESR
- ABG to look for acidosis, hypoxia and hyperkalaemia
- urine dip
- ECG, CXR and renal US
Describe the ECG features in order of hyperkalaemia
- Peaked T waves
- Flattened P waves
- Increased PR interval
- Widened QRS
- VF
Describe the stages of alcoholic liver disease. At what stage is it irreversible?
- Fatty liver -> hepatitis -> cirrhosis
- Cirrhosis
Which liver enzymes are commonly raised in alcoholic liver disease?
- GGT
- AST:ALT >2
What is liver cirrhosis?
-Hepatocellular damage producing areas of nodular regeneration separated by fibrous septae
List some clinical signs of Alcoholic liver disease
- Hands -> Clubbing, leuconychia (low albumin), dupytens contracture, palmar erythema,
- Face -> pallor (ACD)
- Trunk -> Spider naevi, gynaecomastia (decreased liver metabolism)
- Abdo -> hepatosplenomegaly, caput medusa, ascites
- General -> jaundice, bruising (coagulopathy), anorexia
What is portal hypertension? Describe the main features
- Raised portal blood pressure >20mmHg
- SAVE (splenomegaly, ascites, varices (oesophageal, caput medusa, worsening piles) and encephalopathy
Describe portosystemic shunting in portal hypertension. Give the vessels involved in all 3 varices
- Raised portal pressure causes a backflow and increased pressure of blood as blood cannot enter portal system. portal vessels become engorged and dilated causing shifting of blood from the portal system into the systemic system.
- Oesophageal -> Left gastric vein to inferior oesophageal veins
- Caput medusa -> peri-umbilical to superficial abdo
- Haemorrhoids -> superficial rectal to inferior/middle rectal
What can be confused for caput medusa on the abdomen and how do you tell these apart?
- IVC obstruction
- blood flow down below umbilicus = portal hypertension
- Blood flow up below umbilicus = ivc obstruction
Why does portal hypertension cause encephalopathy?
- Decreased blood flow through liver decreases detoxification of blood.
- Build up of toxins in systemic system including ammonia ->cross bbb -> astrocytes clear causing glutamate to glutamine -> osmotic imbalance -> cerebral oedema
Describe the pathophysiology of ascites in liver disease
-Back pressure due to accumulation of blood causes increased hydrostatic pressure leading to fluid exudation. This causes a decrease in circulating volume and RAAS activation which enters a cycle of increased exudation and further RAAS activation. Also decreased albumin and impaired aldosterone metabolism
In broad terms what is anaemia? What general symptoms/signs does it produce?
- Decreased capacity of the haemoglobin to carry oxygen
- Fatigue, pallor, palpitations, light headedness
What are the causes of microcytic anaemia?
- TAILS
- Thalassaemia
- Anaemia of chronic disease
- Iron deficiency Anaemia
- Lead Poisoning
- Sideroblastic anaemia
Describe causes of normocytic anaemia
- Recent blood loss
- Bone marrow failure
- Early ACD
- Pregnancy
What are causes of macrocytic anaemia?
- Vit B12 deficiency
- Folate deficiency
- Reticulocytosis
- liver disease
Give some causes of haemolytic anaemia
- Autoimmune
- Malaria
- Hereditary spherocytosis/elliptosis
- burns
- G6PD deficiency
- Destruction by mechanical heart valves
Give 3 differentials for causes of iron deficiency anaemia
- Poor diet
- Menorrhagia
- Coeliac
Give 2 signs specific for iron deficiency anaemia
- Koilonychia
- Angular stomatitis
What are the causes of b12 deficiency?
- Bacterial overgrowth syndrome (increased use of b12)
- Crohns
- Pernicious anaemia
- Veganism