A+E Flashcards
RFs for AKI?
Age >65 Diabetes HTN Dehydration Nephrotoxic medications CKD Heart failure Rhabdomyolysis Renal tract obstruction Myeloma Liver disease
Pre-renal causes of AKI?
- Hypovolaemia (dehydration, bleeding)
- Septic shock
- Cardiogenic shock
Renal causes of AKI?
- Acute tubular necrosis
- Glomerulonephritis
- Vasculitis
- Interstitial nephritis
- Tubular toxicity ie CT contrast
What are the post-renal causes of AKI?
- Urinary tract obstruction
- Intraluminal ie stone
- Extraluminal ie cancer compression on ureter
What are the diagnostic criteria for AKI?
- Increase in serum creatinine over 0.3umol/L within 48 hrs
- Or inc. in serum creatinine 1.5x baseline
- Or urine volume less than 0.5mL/kg/hr for >6 hrs
What are the creatinine levels for Stage 1 AKI?
1.5-1.9x baseline
What are the creatinine levels for Stage 2 AKI?
2-2.9x baseline
What are the creatinine levels for Stage 3 AKI?
3x baseline
Management aims for AKI?
- Treat underlying cause
2. Prevent further damage by optimising renal blood flow with fluid challenge
What forms the AKI bundle?
- Restore perfusion
- Stop nephrotoxins
- Exclude obstruction
- Treat complications
How is perfusion restored in AKI?
- Fluid challenge
2. Consider vasoconstrictors or inotropes
How do you exclude obstruction in AKI?
- Measure urine output
- CT (stones)
- Renal USS (hydronephrosis)
What are some nephrotoxic drugs?
ACEis/ARBs, NSAIDs
Aminoglycosides (ie gentamicin)
Contrast media
Furosemide and some other diuretics
How does septic shock cause pre-renal AKI?
Sepsis causes leaky vessels; fluid moves from the vessels into the interstitium
What is the main medical cause of acute interstitial nephritis causing AKI?
NSAIDs
What is a side effect of gentamicin? Which drug interacts synergistically?
Ototoxic
Furosemide
Which metabolic abnormalities occur from an AKI and why?
- Hyperkalaemia
- Metabolic acidosis
The transporters work less effectively causing a build up of H+ and K+ and a loss of Na
How is hyperkalaemia treated?
1) Calcium gluconate
2) 10 units Actrapid + 10% glucose
3) Calcium resonium
3 complications of AKI?
- Uraemia
- Metabolic acidosis
- Fluid overload
Headache. What would first and worst/ thunderclap headache suggest?
Subarachnoid haemorrhage
Headache. What would unilateral headache and eye pain suggest?
Cluster headache
Acute glaucoma
Headache. What would unilateral headache and ipsilateral symptoms suggest?
Migraine
Tumour
Vascular
Headache. What would cough-initiated/ worse in morning/ when bending over headache suggest?
Raised ICP/ venous thrombosis
Headache. What would a persisting headache with scalp tenderness in >50s suggest?
Giant cell arteritis
Headache. What would headache with fever/ neck stiffness suggest?
Meningitis
Headache. Aside from associated symptoms, what other questions should you ask a patient presenting with a headache?
- Any recent travel? (?malaria)
- Pregnant? (?pre-eclampsia; esp if proteinuria and HTN)
Also check for any change in pattern of ‘usual’ headaches, and any change in consciousness.
Headache. Differential diagnoses for someone presenting with headaches?
- Tension, cluster, migraine
- Post-traumatic
- Drugs (nitrates, CCBs)
- Carbon monoxide poisoning/ anoxia
- Subarachnoid haemorrhage, Stroke, Subdural haematoma
- Tumour, Cerebral abscess
- Malignant hypertension
- Idiopathic intracranial hypertension
- Any CNS infection
- Encephalitis, meningitis, TB meningitis
- GCS, Acute glaucoma, Certebral artery dissection, Cervical spondylosis, Sinusitis, Paget’s disease, Altitude sickness
Breathlessness. What might be the cause of breathlessness if the patient is wheezing?
- Asthma
- COPD
- Heart failure
- Anaphylaxis
Breathlessness. What might be the cause of breathlessness if the patient has stridor?
- Foreign body/ tumour
- Acute epiglottis (younger patients)
- Anaphylaxis
- Trauma, e.g. laryngeal fracture
Breathlessness. What might be the cause of breathlessness if the patient has crepitations?
- Heart failure
- Pneumonia
- Bronchiectasis
- Fibrosis
Breathlessness. What might be the cause of breathlessness if the patient has a clear chest?
- Pulmonary embolism
- Hyperventilation
- Metabolic acidosis (e.g. DKA)
- Anaemia
- Drugs, e.g. salicylates
- Shock
- Pneumocystis jirovecii pneumonia
- CNS causes
Breathlessness. What might be the cause of breathlessness if there is ‘stony dullness’ to percussion of the chest?
Pleural effusion
Breathlessness. What key investigations should be carried out?
- Baseline observations (O2, sats, temp, peak flow)
- ABG if SpO2 <94% or concern about acidosis/ drugs/ sepsis
- ECG (signs of PE, LVH, MI?)
- CXR
- Baseline bloods: glucose, FBC, U&E, consider drug screen
Chest pain. Give 6 life-threatening causes
Acute MI Angina/ACS Aortic dissection Tension/open pneumothorax Pulmonary embolism Oesophageal rupture Sickle-cell crisis Cardiac tamponade/pericardial effusion
Chest pain. What are the 3 key investigations you would carry out?
- CXR
- ECG
- Bloods: FBC, U+E, troponin. Consider D-dimer
Coma. What is a coma?
Unrousable unresponsiveness
Give 7 metabolic causes of coma
- Drugs, poisoning (carbon monoxide, alcohol, tricyclics)
- Hypo/hyperglycaemia (HONK, ketoacidotic)
- Hypoxia, CO2 narcosis (COPD)
- Septicaemia
- Hypothermia
- Myxoedema, Addisonian crisis
- Hepatic/uraemic encephalopathy
Give 5 neurological causes of coma
- Trauma
- Infection: meningitis, encephalitis (herpes simplex - give IV aciclovir if slight suspicion), malaria, typhoid, etc.
- Tumour (primary or secondary)
- Vascular: stroke, subdural/subarachnoid, hypertensive encephalopathy
- Epilepsy: non-convulsive status or post-octal state
Coma. What is the immediate management?
Airway: protect C-spine; check patent; intubate if GCS <8
Breathing: give 4L high-flow O2
Circulation: IV access
Disability/glucose: give 50ml 20% glucose IV stat if hypo possible
Exposure
Coma. At what GCS would you consider intubation?
If GCS <8
What is the GCS composed of?
EMV (eyes, motor, verbal) 456
What drug would be administered in suspected Wernicke’s encephalopathy?
Pabrinex IV
What drug would be given for opiate intoxication?
Naloxone IV/ IM/ via ETT
What drug would be given for benzodiazepine intoxication?
Flumazenil IV (only if airway compromised)
What is Pabrinex?
Pabrinex is an injection that contains vitamins B and C (thiamine, riboflavin, pyridoxine, nicotinamide and ascorbic acid).
What is the alternative name for Vitamin B1?
Thiamine
What is the alternative name for Vitamin B9?
Folate
Coma. What are the key investigations to be carried out?
- Bloods: ABG, FBC, U&E, ESR/CRP, ethanol, toxic screen, drug levels
- Cultures: blood, urine, consider malaria
- Imaging: CXR, CT head
What alternative to GCS may be used to assess the critically ill?
AVPU (alert; responds to verbal stimuli; responds to pain; unresponsive)
GCS: what does extensor response to pain indicate?
Midbrain damage below the level of the red nucleus
Coma. Which brain pathway is affected?
ARAS (ascending reticular activating sytem)
What causes Cheyne-Stokes breathing?
Brainstem lesions/compression
Define: apneustic
Breath-holding
What may cause ataxic/apneustic breathing?
Brainstem damage (bad prognosis)
Shock. How is MAP (mean arterial pressure) calculated from the systolic and diastolic blood pressure?
1/3 (Systolic BP - Diastolic BP) + Diastolic BP
Shock. How is cardiac output calculated from stroke volume?
CO = SV x HR
Shock. How is MAP calculated from CO?
MAP = CO x SVR (systemic vascular resistance)
Shock. What is shock? What SBP/MAP values might be seen?
Circulatory failure resulting in inadequate organ perfusion
SBP <90mmHg
MAP <65mmHg
Shock. What signs of tissue hypoperfusion might be seen in shock?
Mottled skin/ pallor, cool peripheries, slow CRT Oliguria (Urine output <0.5ml/kg/hr) Serum lactate >2mmol/L Low GCS/agitation Tachycardia Tachypnoea
Shock. What are the two broad causes of inadequate cardiac output?
- Hypovolaemia
2. Pump failure
Shock. Give 2 broad causes of hypovolaemia, and an example of each.
- Bleeding (trauma, ruptured aortic aneurysm, GI bleed)
2. Fluid loss (vomiting, burns, ‘third space’ losses, e.g. pancreatitis, heat exhaustion)
Shock. Give 3 causes of bleeding that may result in hypovolaemia
- Trauma
- Ruptured aortic aneurysm
- GI bleed
Shock. Give 2 causes of fluid loss that may result in hypovolaemia
- Vomiting
- Burns
- ‘Third space’ losses - e.g. pancreatitis, heat exhaustion
Shock. What are the four main causes of shock due to peripheral circulatory failure (loss of SVR)?
- Sepsis
- Anaphylaxis
- Neurogenic (e.g. spinal cord injury, epidural, spinal anaesthesia)
- Endocrine failure (Addison’s disease, hypothyroidism)
What is SIRS?
Systemic inflammatory response syndrome
What are the criteria for SIRS?
2 or more of the following:
- Temp >38 or <36
- Tachycardia >90bpm
- Resp rate >20
- WBC v high or v low
What is sepsis?
SIRS in the presence of infection
What is severe sepsis?
Sepsis with evidence of organ hypoperfusion (eg hyperaemia, oliguria, lactic acidosis, altered cerebral function)
What is septic shock?
Sepsis with hypotension despite adequate fluid resus (or requirement of vasopressors/inotropes to maintain BP)
What type of hypersensitivity reaction is anaphylactic shock?
Type-I IgE-mediated
Give 3 signs of anaphylaxis
- Itching, sweating, D+V, erythema, urticaria, oedema
- Wheeze, laryngeal obstruction, cyanosis
- Tachycardia, hypotension
Give 4 differentials for anaphylaxis
Exacerbation of asthma/COPD
Carcinoid
Phaeochromocytoma
Systemic mastocytosis
Hereditary angioedema
Why would you measure serum tryptase in a patient?
To check whether they have had an anaphylactic reaction
Anaphylaxis. Which cells release tryptase?
Mast cells
Anaphylaxis. What is the immediate management for anaphylaxis?
ABCDE
- Secure airway - give 100% O2; intubate if necessary
- Remove cause; raise feet to restore circulation
- Adrenaline IM 0.5mg of 1 in 1000; repeat every 5min if needed
- IV access
- Chlorphenamine (Piriton) 10mg IV and Hydrocortisone 200mg IV
- IVI 0.9%NaCl as needed
- Admission to ICU if still hypotensive
Anaphylaxis. How would a patient be further managed once admitted to ICU?
- IVI adrenaline may be needed +/- aminophylline
- Nebulised salbutamol
- Admit to ward, monitor ECG
- Measure mast cell tryptase 1-6h after suspected anaphylaxis
- Continue chlorphenamine if still itching
Anaphylaxis. What dose of adrenaline would be given IM?
What are the risks of giving adrenaline IV?
0.3-0.5mg of 1 in 1000 adrenaline
Indicated in extremes of each system, e.g. stridor/wheeze, hypoTN, drowsy
Risks of IV: palpitations, SoB, N+V, MI, arrhythmia
STEMI. What would the initial investigations be?
- History and examination
- ECG
- Bloods: FBC, U&E, troponin, glucose, cholesterol
- CXR
STEMI. Initial management?
Offer pain relief asap (GTN or morphine)
ECG and IV access (take bloods, inc Trop I/T)
Aspirin 300mg
Morphine 5-10mg IV + antiemetic (e.g. metoclopramide)
Primary PCI (STEMI on ECG and PCI <120 mins)
OR
Fibrinolysis if not
Shock. What is cariogenic shock?
When the decline in CO is due to a decrease in contractility or dysrhythmias
Shock. What signs might suggest anaphylactic shock?
Lip/tongue swelling (angioedema)
Inspiratory stridor
Urticaria
Hx of atopy
Shock. What is the shock index?
HR/SBP
Shock. What shock index value indicates shock?
Shock index >0.8
Shock. What might an elevated eosinophil count suggest?
- Anaphylaxis
2. Adrenal insufficiency
Shock. What are band cells, and what do they suggest?
Immature neutrophils
Fairly specific for sepsis
Shock. What might elevated BUN (blood urea nitrogen) and Creatinine levels indicate?
Pre-renal AKI secondary to hypovolaemia
Shock. If an MI is suspected, what investigation should be carried out?
Troponin levels
Shock. If congestive heart failure is suspected, what 2 investigations should be carried out?
- CXR
2. BNP levels
Shock. What are the 2 types of hypovolaemic shock?
- Haemorrhagic
2. Non-haemorrhagic
Shock. What are the main causes of non-haemorrhagic hypovolaemic shock?
- GI: D&V
- Renal: excessive diuresis (DKA) or diabetes insipidus
- Excessive sweating
- Third-spacing
Shock. What is third spacing?
Anything that causes intravascular fluid to shift into the interstitial/intracellular space
Shock. Give 3 examples of ‘third space’ losses that could cause hypovolaemic shock
- Burns
- Intestinal obstruction
- Acute pancreatitis
Shock. What would you want to rule out in an elderly patient presenting with back/flank pain, syncope and hypotension?
Ruptured AAA
Shock. What type of blood can be given if the patient’s blood type is unknown?
O negative
Shock. What is an anaphylactoid reaction?
When a trigger (e.g. opioids) induce release of mediators in a non-IgE-dependent fashion
Anaphylaxis. How does adrenaline work to manage anaphylaxis?
- Vasoconstriction
- Increases CO
- Relaxes smooth muscle of the airway
Anaphylaxis. What is the issue with giving adrenaline to someone on a beta blocker?
Beta blockers can blunt the effect of adrenaline
Anaphylaxis. What can be given to potentiate the effects of adrenaline in someone who is on a beta blocker?
Glucagon
What can cause a delayed deterioration in anaphylaxis?
Digestion of food
Delayed histamine response
Anaphylaxis. What is the ‘biphasic reaction’?
When a less severe episode of anaphylaxis recurs within 72 hours of the initial reaction
Anaphylaxis. What can be given to reduce the risk of a biphasic reaction?
Glucocorticoids such as methylprednisolone (delayed onset of action)
Anaphylaxis. What is Kounis syndrome?
MI following anaphylaxis
Occurs in people with pre-existing CHD as they have lost of mast cells in coronary circulation which can trigger plaque rupture when anaphylaxis occurs
Neurogenic Shock. What is the sympathetic innervation of the heart?
T1 to T5
Neurogenic Shock. How might injury to T1-T5 affect the blood pressure? Why?
Hypotension
T1-T5 responsible for sympathetic innervation to the heart; injury results in unopposed parasympathetic stimulation -> vasodilation and bradycardia
Neurogenic Shock. How is it treated?
- IV Crystalloid fluids
2. Vasopressors (noradrenaline, phenylephrine, dopamine)
What is spinal shock?
Temporary state of flaccid paralysis and loss of sensation below the level of spinal cord injury
Shock. Which hormones are depleted in adrenal insufficiency?
- Cortisol
2. Aldosterone
What type of hormone is cortisol?
Glucocorticoid
What type of hormone is aldosterone?
Mineralocorticoid
Shock. What typically causes adrenal insufficiency?
- Sudden cessation of chronic exogenous glucocorticoids (e.g. in someone with asthma or COPD)
- Failure to increase the dose during stress (e.g. infection, surgery)
Shock. How is shock due to adrenal insufficiency treated?
- IV Hydrocortisone (to replace cortisol)
2. IV Fludrocortisone (to replace aldosterone)
Shock. What causes toxic shock syndrome?
Bacterial endotoxins that act as superantigens - generate hyperactive immune response
AKI. Pre-renal AKI is characterised by an ___ ratio of BUN:Creatinine and a ___ fractional excretion of sodium
- Elevated BUN:Creat ratio (>20)
2. Low fractional excretion of sodium (<1%)
Shock. What type of shock is associated with loss of sympathetic nervous system stimulation throughout the body?
Neurogenic shock
Shock. In a patient with bradycardia, hypotension, poikilothermia and priapism, what type of shock would be suspected?
Neurogenic shock
Shock. What is poikilothermia?
Inability to control body temperature; seen in neurogenic shock
Shock. What is Beck triad?
- Distended neck veins
- Muffled heart sounds
- Hypotension
its presence is characteristic of cardiac tamponade
Shock. Why is the patient warm and flushed without perspiration in neurogenic shock?
Systemic vasodilation -> warm and flushed
Without perspiration -> sweat glands are sympathetically controlled
Shock. What happens to the systemic vascular resistance in neurogenic shock?
Decreases (due to lack of sympathetic signalling -> widespread vasodilation)
Anaphylaxis. What type of reaction is associated with contact dermatitis or a delayed hypersensitivity reaction?
Type IV hypersensitivity
Shock. 26F comes to A&E w/ altered mental status, high fever and diffuse rash on lower limbs.
She is lethargic but arousable. T 39°C, HR 110bpm, Resp 33/min, BP 90/50mmHg. She is given 2 IV fluid boluses - no change in BP.
Started on treatment. Blood culture shows ++ G-ve diplococci.
Which of the following molecules is primarily involved in this patient’s condition?
a) IFN-beta
b) IL-10
c) IL-2
d) IL-3
e) TNF-alpha
e) TNF-alpha
Major mediator of septic shock
Shock. Which molecule is the major mediator of septic shock?
TNF-alpha
Shock. What type of cell releases TNF-alpha?
Macrophages