Paper 3 stuff

Question 1

ECG pulmonary hypertension

Answer 1

P-pulmonale
RV strain or hypertrophy
Right axis deviation
RBBB
Prolongation of QRS and /or QTc in severe disease

Question 2

Brugada syndrome

Answer 2

Brugada Syndrome- Type 1 pattern.

📍It is a rare inherited cardiac channelopathy caused by mutations in cardiac sodium channels (SCN5A gene), leading to abnormal cardiac electrical activity.
Risk of VT & VF leading to syncope, seizures, or sudden cardiac death.
🔹Often presents in young to middle-aged males, sometimes asymptomatic until sudden death.
🔹Symptoms may worsen with fever or certain drugs.

Question 3

Dx of Brugada ECG

Answer 3

Type 1 ECG Pattern= Coved ST-segment elevation >2 mm in leads V1-V3 followed by a negative T wave.
Known as the Brugada sign, this pattern can be spontaneous or unmasked with sodium-channel blockers.

Question 4

Absolutely C/I to TEE

Answer 4

Esophageal stricture/ tumour/ diverticulum/ perforation/ laceration
Active upper GIT bleed

Question 5

Question 6

ECG..What do you see?

Answer 6

U waves. Hypokalemia
U wave bigger than T wave
Note slightly marked p waves

Question 7

ECG

Answer 7

Hyperkalemia

Question 8

ECG

Answer 8

TCA toxicity

Question 9

ECG

Answer 9

Multifocal atrial tachycardia

Question 11

3 qualitative methods of global systolic function

Answer 11

1. Change in 2D size of the LV cavity
2. Thickening of the LV walls
3. Wall motion abnormalities

Question 12

Quantitative methods of measuring LV systolic function

Answer 12

1. EF (52-72%)
2. Fractional shortening (25-45%)
3. Fractional area change (>40%)
4. E-point septal separation (<7mm)
5. Mitral Annular Plane Systolic Excursion (MAPSE) 12-15mm

Question 13

Fractional shortening formula

Answer 13

FS%= LVEDD- LVESD/LVEDD ×100

Question 14

Fractional area change formula

Answer 14

FAC= LVEDA - LVESA/ LVEDA ×100

Question 15

Limitations of EPSS

Answer 15

Mitral stenosis
Mitral valve repair
Severe AR
RWMAs
Severe LVH/ HOCM

• > 7mm is abnormal
  15mm indicates severe LV systolic failure

Question 17

What is McConnell sign?

Answer 17

McConnell’s sign describes akinesia of the RV free wall with preserved apical contraction. It can be seen in acute RV failure from any cause.

Question 18

A-a gradient calculation

Answer 18

A−a Gradient=PAO₂−PaO₂
PAO₂=(PB−PH₂O)×FiO₂− ( 0.8 PaCO₂/ RQ)

Where:
PB = Barometric pressure (usually 760 mmHg at sea level)
PH₂O = Water vapor pressure ( 47 mmHg at body temp)
FiO₂ = Fraction of inspired oxygen (e.g., 0.21 for room air)
PaCO₂ = Partial pressure of CO2 in arterial blood
RQ= Resp quotient normally 0.8
After calculating PAO₂, the A-a gradient can be determined by subtracting the arterial oxygen pressure (PaO₂)

Question 19

DO2 (Oxygen delivery) calculation

Answer 19

DO2 = CaO2 × CO × 10
CaO2 = (1.39 × Hb × SaO2) + (0.003 × PaO2)
Where:
Hb is the hemoglobin concentration (g/dL),
SaO2 is the arterial oxygen saturation (%),
PaO2 is the partial pressure of oxygen in arterial blood (mmHg)

Question 21

ECG changes in hypothermia

Answer 21

Bradyarrhythmias
Osborne Waves (= J waves)
Prolonged PR, QRS and QT intervals
Shivering artefact
Ventricular ectopics
Cardiac arrest due to VT, VF or asystole

Question 22

Findings and diagnosis

Answer 22

Short PR interval (< 120ms)
Broad QRS (> 100ms)
A slurred upstroke to the QRS complex (the delta wave)

Question 23

Normal QTc values

Answer 23

QTc is prolonged if > 440ms in men or > 460ms in women
QTc > 500 is ass with increased risk of torsades de pointes
QTc is abnormally short if < 350ms
A useful rule of thumb is that a normal QT is less than half the preceding RR interval

Question 24

Causes of a prolonged QTc (>440ms)

Answer 24

Hypokalaemia
Hypomagnesaemia
Hypocalcaemia
Hypothermia
Myocardial ischemia
ROSC Post-cardiac arrest
Raised intracranial pressure
Congenital long QT syndrome
Medications/Drugs

Question 25

Corrected QT interval (QTc)

Answer 25

QTC = QT / √ RR The RR interval is given in seconds (RR interval = 60 / heart rate). | The corrected QT interval (QTc) estimates the QT interval at a standard

Question 26

Causes of a short QTc (<350ms)

Answer 26

* Hypercalcaemia * Congenital short QT syndrome * Digoxin effect

Question 27

Normal A-a gradient

Answer 27

Gradient varies with age and FiO2: A normal A–a gradient for a young adult non-smoker breathing air, is between 5–10 mmHg. FiO2 0.21 – 7 mmHg in young, 14 mmHg in elderly FiO2 1.0 – 31 mmHg in young, 56 mmHg in elderly For every decade a person has lived, their A–a gradient is expected to increase by 1 mmHg – a conservative estimate of normal A–a gradient is < [age in years/4] + 4.

Question 28

# Causes Hypoxia with normal A-a gradient

Answer 28

1. Alveolar hypoventilation (elevated PACO2) 2. Low PiO2 (FiO2 < 0.21 or barometric pressure < 760 mmHg) -high altitude

Question 29

# Causes Hypoxia with high A-a gradient

Answer 29

Diffusion defect : emphysema, interstitial lung disease V/Q mismatch: COPD, pneumonia, pulmonary oedema Right-to-Left shunt (intrapulmonary or cardiac): atelectasis, ARDS, severe pneumonia, ASD with Eisenmenger Increased O2 extraction (CaO2-CvO2) ### PaCO2 may be normal or low Do not fully correct with oxygen, especially shunt

Question 30

Anion gap

Answer 30

Anion Gap = (Na+ + K+) – (Cl- + HCO3-) Normal = 12 (+/-4)

Question 31

Blood gas interpretation flowchart | Revise

Answer 31

Question 32

Causes if high anion gap metabolic acidosis

Question 33

# Causes HAGMA

Answer 33

Question 34

Winter's formula for expected pCO2

Answer 34

pCO2 expected = (1.5 x [HCO3­–]) + 8 ±2 If measured pCO2 is different from expected, there is a mixed acid base disorder If the measured pCO2 is more than the expected pCO2 – there is also a respiratory acidosis

Question 35

Delta ratio

Answer 35

Question 36

what is the 1-2-3-4-5 rule for calculating expected bicarb

Answer 36

Question 37

Compensation in respiratory acidosis

Answer 37

*For acute respiratory acidosis* For every 10mmHg CO2 rises above 40, expect HCO3 to rise by 1mmol/L *For chronic respiratory acidosis * For every 10mmHg CO2 rises above 40mmHg, expect HCO3 to increase by 4mmol/L

Question 39

Expected pCO2 in metabolic alkalosis

Answer 39

pCO2 expected = (0.7 x [HCO3–]) + 20 ± 5 If the measured pCO2 is more than the expected pCO2 – there is also a respiratory acidosis occurring If the measured pCO2 is less than expected – there is a concurrent respiratory alkalosis.

Question 40

Albumin correction of anion gap

Answer 40

Anion gapAlbumin corrected = Anion gap + 0.25 (40 – Albumin) Albumin is an anion, therefore hypoalbuminaemia may under-estimate the anion gap. To correct the anion gap for hypoalbuminaemia –** for every 10g/L that the albumin is below normal (40g/L) add 2.5 to the calculated anion gap**

Question 41

QRS axis calculation based on LeadI and AVF

Answer 41

Question 42

Formula for SVR

Answer 42

Question 43

PVR formula

Answer 43

Question 44

ECG changes with electrolyte abnormalities Potassium Calcium Magnesium

Answer 44

Question 46

mPAP calculation formula

Answer 46

mPAP= (PASP + [2×PADP]) /3

Question 47

Components of pulmonary artery catheter

Question 48

Henderson-Hasselbalch equation

Answer 48

pH= 6.1+log(HCO3/PaCO2X0.03)