Emergency Medicine Flashcards
EM MD3012
Normal sinus rhythm
Diagnosis: Atrial Fibrillation
Justification: No clear P waves, rapid ventricular rate 150/min, irregularly irregular rhythm
Diagnosis: Ventricular tachycardia
Justification: Broad complex tachycardia 160/min
Diagnosis: Sinus rhythm with first degree heart block
Justification: Every P wave is followed by a QRS, however PR interval prolonged >200ms
Diagnosis: Atrial flutter with 4 to 1 block
Justification: Regular rhythm, P wave rate of 300/min, QRS ventricular rate of 70/min, “Saw tooth pattern” in lead 2
Atrial flutter
YES
VENTRICULAR FIBRILLATION
No discernible organised rhythm. The rate is less than 400/min
It is important to note that this is not Torsades (also known as polymorphic VT)
.
Second-degree heart block Type 1
progressively longer PR intervals then a dropped beat. Clustering of the QRS complexes
Diagnosis: Second degree Mobitz type 2
Justification: Regular rhythm, every second P wave is not followed by a QRS (dropped beat), fixed PR interval for the normal conducted beat
Diagnosis: High lateral STEMI
Justification: ST elevation in I and aVL
Diagnosis: Complete heart block (3rd degree heart block)
Justification: No relationship between P waves and QRS complexes, P wave rate of 70-90/min, QRS rate of 42/min,
Narrow QRS complexes suggesting escape rhythm is from AV node rather than lower in ventricles
Diagnosis: Inferior STEMI
Justification: ST elevation in II, III, aVF
Diagnosis: Pericarditis
Justification: Widespread concave ST elevation with PR depression and reciprocal PR elevation in AVR, Spodick’s sign in lead II
Diagnosis: Supraventricular tachycardia (Atrioventricular nodal re-entrant tachycardia)
Justification: Narrow complex tachycardia, absent P waves, Rate >140
Left lower lobe pneumonia with loss of left hemidiaphragm and preservation left heart border
Free air under the diaphragm, likely from bowel perforation eg ulcer
Widened mediastinum from aortic dissection – either traumatic or atraumatic
Left upper lobe pneumonia involving lingular segment of left upper lobe, demonstrated by loss of left heart border
Bilateral pleural effusions eg congestive heart failure
Right large pleural effusion with meniscus sign eg haemothorax if trauma, exudate / pus if empyema, transudate or exudate if malignancy related effusion
Right upper lobe pneumonia with preservation of right heart border and opacification sitting above right horizontal fissure
Right pneumothorax with absent peripheral lung markings
COPD with hyperinflation (>7 anterior ribs), flattened hemidiaphragms, reduced lung markings, small heart size. Caution bilateral breast shadows may be misinterpreted as pneumonia / opacification.
XRAY 10 - Cardiomegaly
Right middle lobe pneumonia with loss of right heart border but preservation of right hemidiaphragm
Subcutaneous emphysema (free air in skin and soft tissues) demonstrated by free air seen in left and right lower chest wall soft tissues and right upper neck soft tissues. eg from chest trauma, free air leaking from lungs into soft tissues
Pneumomediastinum (free air in mediastinum involving the pericardial sac), eg from Boerhaave’s syndrome perforated oesophagus. Incidentally, note the subcutaneous emphysema in right lateral chest wall soft tissues and neck soft tissues.
Acute pulmonary oedema demonstrated by opacification of both lung fields in the context of no fever or cough. Note: If clinical history suggested fever and cough then this Xray could be interpreted as bilateral pneumonia!
Right lower lobe pneumonia with preservation of right heart border
Large bowel obstruction with dilated loops of bowel. Large bowel because there are plicae semilunares that do not cross bowel lumen.
Small bowel obstruction with dilated loops of bowel. Small bowel because there are plicae circulares that cross the entire lumen.
Small bowel obstruction with dilated loops of bowel AND air fluid levels. Small bowel because there are plicae circulares that cross the entire lumen.
What are the differential diagnoses for a respiratory acidosis?
NAILED
Neuromuscular
- Guillian Barre
- Motor neuron
- Snake bite
Airway obstruction
- Anaphylaxis
- Trauma
ICP Raised
- Stroke
- Head injury
Lung Pathology
- COPD
- Pneumonia
- APO
- Severe asthma
Epilepsy
- Post seizure
Drugs
- Sedatives or analgesics e.g. morphine or diazepam
- Paralytics
What are the differential diagnoses for a Metabolic Acidosis NAGMA
ABCD
Adrenal insufficiency - Addison’s disease
Bicarbonate Loss - Renal tubular acidosis
- GI diarrhoea
- Ileal conduits
Chloride Excess
- Sodium chloride IV
Drugs
- Acetazolamide
- Spironolactone
What are the differential diagnoses for a Metabolic Acidosis HAGMA
KARMEL
Ketones
- Diabetic ketoacidosis
Aspirin
Renal Failure
Methanol
Ethylene Glycol
Lactate
- Sepsis
What are the differential diagnoses for a Metabolic Alkalosis
GLARE
Gut losses
- Vomiting / NG losses
Lung COPD
- COPD chronic hypercapnia with metabolic alkalosis then acute hyperventilation
Alkali excess
- Antacids, milk alkali
- HCO3 infusion
Renal
- Diuretics e.g. frusemide
- Barters syndrome
Excess Endocrine
- Aldosterone excess
- Cushing’s
- Steroids
What are the differential diagnoses for a Respiratory Alkalosis
5P’s
Pain
Panic
Pregnancy
asPirin
hyPoxia
A 6 year old boy presents with his parents with a five day history of profound watery diarrhoea. Interpret his arterial blood gas: pH 7.22, pC02 18, HCO3 6, Na 140, K 4, Cl 120, Lactate 1.5, BSL 2.6
Dx: NAGMA with adequate resp compensation, expected CO2 17 via Winters (8+1.5x6=17) thus adequate compensation, AG 14 (140-120-6=14) which is upper limit but normal. DDx for NAGMA = ABCD, bicarbonate loss from diarrhoea. Bonus mark if recognised hypoglycaemia BSL <4
A 26 year old woman with type 1 diabetes presents with vomiting and reduced level of consciousness. Interpret her ABG: pH 7.05, pCO2 38, HCO3 16, Na 132, K 5, Cl 92, BSL 50
Dx: Metabolic acidosis with mild respiratory alkalosis compensation. Winters expected CO2 1.5x16+8=32, but actual CO is 38, thus there is a resp acidosis second disorder. AG 132-92+16=24, DDx for HAGMA = KARMEL = likely diabetic ketoacidosis. Overall diagnosis of DKA metabolic acidosis with inadequate respiratory compensation and concurrent respiratory acidosis due to hypoventilation from reduced level of consciousness (part of severe DKA)
22 year old female with chest pain, paraesthesia and dizziness. Interpret her ABG: pH 7.49, pC02 28, HCO3 22, Na 135, K 4.6, Cl 99 BSL 5, Lactate 0.7
Dx Resp Alkalosis, with mild renal / metabolic compensation. DDX resp alkalasis = 5Ps eg panic attack hyperventilating, consider chest pain causing hyperventilation. DDx for chest pain include PE, amphetamines/cocaine causing angina, pericarditis, pancreatitis
ROLE OF EMERGENCY PHYSICIAN
- Resuscitationist (e.g. cardiac arrest, thrombolysis, severe sepsis, severe trauma, intubation, defibrillation, thoracotomies, IO)
- Generalist (e.g. ingrown toe nails, diarrhoea, chronic back pain, drug seekers, suicidal ideation, FB from ears/ noses, coughs and colds, miscarriages)
- Diagnostician (e.g. always looking for the red flags or the life threats)
The triage system acknowledges 5 special populations that may not necessarily be treated in accordance with the typical triage rules (due to their high risk / increased urgency)
- Elderly (>65 years; medications, don’t mount immune response)
- Paediatrics (<3months; neonates rapidly deteriorate, might look well initially)
- Pregnancy (different vital signs, 2 lives involved)
- Mental health (may have normal vitals but have behavioural disturbances which pose a risk to them and those around them)
- Poisonings (can have normal vitals initially, but may rapidly deteriorate)
When interpreting a blood gas, an easy way to approach it using the following 4 step process;
- Look at the pH
- Is there Acidaemia? (pH is down)
- Or is there Alkalaemia? (pH is up) - What is the primary disturbance?
- Is it a metabolic (CO2) processes that is causing the disturbance?
- Or is it a respiratory (HCO3) process that is causing the disturbance? - Is their compensation?
- That is, has the body made steps to reverse the current pathological blood gas state through compensation
- The body can compensate through either metabolic or respiratory processes
- If there is a metabolic acidosis, compensation is determined through the Winters Formula (provides the expected carbon dioxide level should be for a specific metabolic acidosis, basically so we can determine if there is adequate compensation letting us know if there is a secondary respiratory disorder) - Determine a differential diagnosis
- This is done using a differential diagnosis table
WINTERS FORMULA
metabolic acidosis
The formula is as follows;
Winters formula=(1.5*Bicarbonate)+8
Step 3: Because the patient is in metabolic acidosis, we use Winter’s formula to decipher whether there is appropriate respiratory compensation. (1.5*6) + 8 = 17. As the actual CO2 is 18 there is appropriate respiratory compensation (it is important to note that if CO2 levels where below 40 but not close to 17, it would show a metabolic acidosis with a concurrent respiratory acidosis
ANION GAP
- Metabolic Acidosis NAGMA (Normal Anion Gap)
- Metabolic Acidosis HAGMA (High Anion Gap)
Using the above example, the following is true;
- Anion Gap = Na – HCO – Cl
Using the normal anion gap range of 6 to 14
ECG INTERPRETATION
When interpreting ECGs, the acronym RRABI can be used. The breakdown is as follows;
1. Rate
- Find the heart rate
- One method of determining rate is by counting the QRS complexes in rhythm strip and multiplying by 6
- Can be either Tachycardia (faster than normal) or Bradycardia (slower than normal)
2. Rhythm
- Check for P waves before each QRS complex and ensure there is regularity
- The best leads to check this are V1 and V2
- Can be Sinus Rhythm, SVT, AF, Aflutter, VF or VT
3. Axis
- Can be either normal, left axis or right axis
- This is found by checking the QRS complex’ in leads 1 (left) and aVF (right)
- If there are ‘two thumbs up’ it is normal
- If they are leaving each other it is left axis
- If they are pointing towards each other it is right axis
4. Block
- There are two different types of blocks, AV blocks and Bundle branch blocks
- When the PR interval is more than 200ms, it indicates an AV block (5 small squares as each square is 0.04 seconds so 5 small squares)
- When the QRS interval is more than 120ms it indicates a Bundle branch block (3 small squares)
- AV blocks can further be classified as; 1st degree, 2nd degree (type 1 and 2) and 3rd degree heart block
- Bundle branch blocks can further be classified as either LBBB or a RBBB
5. Infarction
- Is shown by our ST Segment Elevation
- Can indicate the following; Anterior STEMI, Lateral STEMI, Inferior STEMI or Pericarditis
CHEST X-RAY INTERPRETATION
As with CPR, when interpreting chest X-rays the acronym DRS ABCDE is used
1. Details
- Patient Name and Date of Birth
- Date and Film Type
2. RIPE Image
- Rotation: When checking if the film is rotated, look at the distance from the edge of the clavicle to the spinous processes. If equal on both sides, the image is not rotated
- Inspiration: When checking for normal inspiration, count the number of anterior ribs shown (normal is between 5 – 6)
- Projection: Refers to the direction in which a chest x-ray is taken. It can be either AP (anterior to posterior) or PA (posterior to anterior). This is important because the heart appears 25% bigger than its actual size in AP. A PA film will never show the scapula’s (as they are externally rotated due to the position taken by the patient during imaging)
- Exposure: An x-ray with normal exposure should show the lumbar vertebrae. If the photo is underexposed, they won’t be visible (too white). In a clinical scenario this could mean pathologies appear more serious than they are
3. Soft Tissues and Bones
4. Airways and Mediastinum
- Check the trachea midline (is it shifted suggesting a pneumothorax)
- Measuring the mediastinum occurs at the carina (level of the bifurcation of the left and right bronchus) from the left to right margins. If it is more than 8cm it is pathological (possible aortic dissection)
5. Breathing
- Observe the various Lung fields, comparing from left to right
- Observe the pleura
6. Circulation
- Look for heart position, its borders, shape and size (diameter should be less than 50% of the diameter of the entire chest. In other words, the cardio-thoracic ratio should be less than 50%)
7. Diaphragm
- Observe both hemidiaphragms (meaning each half of the diaphragm)
8. Extras
- Any extra thingamajigs in there e.g. plastic, PICC lines etc.
PAEDS vs. ADULT AIRWAY
When practicing emergency medicine, it is important to realise that the airways differ significantly between paediatric patients and adult patients
The key differences are outlined below;
1. Occiput size
- The occiput is the back of the head, in paediatrics patients this will be much larger in relation to their body when compared with adults
- As a result, paediatrics heads are typically flexed when lying down, occluding the airway
2. Tongue size
- Paediatric patients have a bigger tongue in relation to their size when compared with adults
- This larger tongue impedes the view
3. Soft palette
- A child’s soft palette is much more friable (tissue that readily tears, fragments or bleeds when palpated or manipulated) making intubation difficult
- This increases risk of bleeding from laryngoscope etc.
4. Epiglottis
- A child’s epiglottis is much bigger and floppier compared to adults
5. Larynx
- The larynx is much more anterior (forward) in a child making intubation more difficult due to reduced cord visibility
6. General shape
- A child’s airway resembles a funnel shape (compared to the cylinder shape in an adult) with the narrowest part at the level of the cricoid (known as the cricoid ring)
- This means that often you can navigate through the vocal cords well, but once the Endotracheal tube passes through it may get stuck at the cricoid
- In adults the vocal cords are the narrowest point
DIFFICULT AIRWAY: LEMON
BRONCHIOLITIS vs. ASTHMA
Chronic bronchitis vs emphysema
cardiogenic pulmonary oedema vs non-cardiogenic
STEMI position and corresponding lead
STEMI – MANAGMENT
SHOCK – CAUSES (IMPORTANT)
- Septic and Distributive shock (an issue with blood vessels vasodilating, effecting the distribution of the blood, not the volume)
- Septic shock (sepsis)
- Anaphylactic shock (anaphylaxis)
- Neurogenic shock - Hypovolaemic shock (not enough blood)
- Haemorrhagic
- Fluid loss - Obstructive shock (vessels being blocked)
- Tamponade
- Tension Pneumothorax
- Thromboembolism (pulmonary embolism) - Cardiogenic shock (issue with the pump)
- Rhythm (Tachy VF / VT, Bradycardia 3DHB
- Ventricles (STEMI, Cardiomyopathy, Myocarditis)
- Valves (Mitral regurg, Aortic Stenosis, Endocarditis) - Kemicals kill you shock (Dissociative shock as they cause oxygen to become dissociated off the Haemoglobin because of the chemicals)
- Carbon Monoxide
- Cyanide
- Methemoglobinemia
WHat is the triad of death
Interpreta qSOFA score for sepsis
QUICK SOFA (qSOFA)
Is not a diagnostic tool for sepsis, but instead is a predictor of mortality
The Quick SOFA score does this through using the following 3 parameters;
1. Low Blood Pressure
- Systolic Blood pressure less than or equal too 100mmHg (1 point)
2. Respiratory Rate high
- 22 or more breaths per minute (1 point)
3. Altered consciousness
- Glasgow Coma Score of less than 15 (1 point)
If a patient has a score of 2 or more with sepsis, the patient has a 10% mortality
It is important to remember the qSOFA score does not diagnose sepsis, but is instead a predictor of mortality (tells us which patients with sepsis we need to watch closely)
Assessment qSOFA Score
Low Blood Pressure (SBP ≤ 100mmHg) 1
High Respiratory Rate (>/= 22 breaths/min) 1
Altered mentation (GSC <15) 1
CARDIAC ARREST – COACHED
what is the classification system of stroke
TRAUMA ASSESSMENT AND MANAGEMENT
CHEST DRAIN
TRAUMATIC INTRACRANIAL HAEMORRHAGE types
SPinal injury myotomes
incomplete spinal cord syndromes
COLLES FRACTURE
Is a fracture of the distal portion of the radius / ulna with dorsal angulation
This is common in patients who fall upon a an outstretched hand bending the forearm backwards
Features present on exam will include;
1. Dinner fork deformity
2. Median nerve injury
- Numbness over the thenar eminence
3. Ulna nerve injury
- Froment’s sing
- Ulna claw
BARTON FRACTURE
Is a fracture of the distal radius through the dorsal aspect to the articular surface
This is common in patients who fall onto a dorsiflexed wrist
Features present on an exam will include;
1. Median nerve injury
- Numbness on thenar eminence
2. Ulna nerve injury
- Frogment’s sign
- Ulna claw
This fracture effects the intra-articular surface of the wrist making it an unstable fracture
On the X-ray it is known as a dorsal cortex break (a break of the cortical bone)
SMITH FRACTURE
Is a fracture of the distal portion of the radius/ulnar with volar angulation
This is common in patients who fall upon an outstretched hand
Features present on an exam will include;
1. Garden-spade deformity
2. Median nerve injury
- Numbness over the thenar eminence
3. Ulna nerve injury
- Froment’s sign
- Ulna claw
MONTEGGIA FRACTURE (MU)
Is a fracture of the proximal third of the ulna with dislocation of the proximal head of the radius
History is usually a fall on a dorsiflexed wrist
Features present on an exam include;
1. Median nerve injury
- Numbness on the thenar eminence
2. Ulna nerve injury
- Froment’s sign
- Ulna claw
Features on an X-ray include a fracture in the proximal third of the ulna, an intact radius and a dislocation of the proximal head of the radius
GALLEAZZI FRACTURE (GR)
Is a fracture of the distal third of the radius with dislocation of the distal radioulnar joint as well as dislocation of the ulna styloid from the radioulnar joint
History is usually a fall on a dorsiflexed wrist
The features present on an exam are;
1. Median nerve injury
- Numbness over the thenar eminence
2. Ulna nerve injury
- Foments sign
- Ulna claw
The signs on an X-ray will be a fracture in the distal third of the radius, an intact ulna bone with dislocation of the ulna styloid process from the radioulnar joint
FRACTURE CLASSIFICATION – WEBBER
Are fibular fractures that are classified into 3 different types relative to the syndesmosis (is the immovable fibrous joint between the distal fibula and tibia)
In other words, are fractures of the fibular classified based on where they occur
The more proximal the fracture, the higher the risk of syndesmotic disruption and ankle instability
There are 3 types;
1. Weber A
- Below syndesmosis (Is at the tip of the lateral malleolus)
- Most stable
2. Weber B
- At the level of the syndesmosis (in the middle of the lateral malleolus)
3. Weber C
- Above the level of the syndesmosis (above the lateral malleolus)
- Is the most unstable
- Requires immobilisation and surgical repair
MAISONNEUVE FRACTURE
Is a spiral fracture of the proximal third of the fibula with an unstable ankle (typically representing a ligamentous injury)
History includes an eversion injury, inability to weight bear and pain the median ankle
Also shows a foot drop due to peroneal nerve injury
Features on an x-ray include;
- Talar shift leading to widening of the joint space between talus and medial malleolus (deltoid ligament rupture)
- No fracture in the ankle
- Spiral fracture of the proximal fibula
PELVIC FRACTURES
YOUNG-BURGESS CLASSIFICATION
YOUNG-BURGESS CLASSIFICATION
Are pelvic fractures are typically associated with extremely traumatic events (falling off a roof, getting hit by a bus etc.)
This type of fractures are very serious, and require serious medical attention
There are 3 important types;
1. Lateral compression (hit from the side)
- Show reduced pelvic volume
- Typically caused by a side impact motor vehicle accident or pedestrian hit on the side of the hip by a car
2. Anterior posterior compression (hit from the front or back)
- Show symphysis pubis widening
- Motorbike head on collision causing pelvis to hit fuel tank
- Have a high mortality from bleeding
3. Vertical shear (force from below)
- Shows raised level of femoral heads
- Jumping from height landing on one leg or motor vehicle accident knee into the dashboard
- Have a high mortality from bleeding
These patients can bleed to death as the area is highly vascular
Bleeding is stopped via embolization
differentiating whether the cause is psychiatric or organic in nature
