Cardiac
What is the normal PR interval?
0.12–0.20 seconds (120–200 ms, or 3–5 small squares)
What does the dicrotic notch on an arterial waveform represent?
Aortic valve closure
Name the four main categories of shock.
Hypovolaemic, cardiogenic, distributive, obstructive
What is the first-line vasopressor for septic shock according to Surviving Sepsis guidelines?
Noradrenaline
Name a CRM principle/non-technical skill
Teamwork, leadership, role clarity, communicate, cognitive aids, mobilise resources, distribute workload, Situational awareness, call for help early, know your environment, anticipate and plan
A rhythm strip shows no P waves and an irregularly irregular rhythm. What is the most likely diagnosis?
Atrial Fibrillation
What is the "fast flush test" (square wave test) used for?
To assess the dynamic response of the arterial line system — checking for overdamping or underdamping
A patient has warm peripheries, bounding pulses, low BP, and fever. What type of shock is most likely?
Distributive shock (septic — "warm shock")
Noradrenaline primarily acts on which adrenergic receptors?
Alpha-1 (vasoconstriction) with some beta-1 activity
What is M3 on the GCS score?
Motor response - abnormal flexion
ST elevation in leads II, III, and aVF indicates ischaemia in which coronary territory?
Inferior — Right Coronary Artery (RCA) or circumflex
A dampened arterial waveform shows a slurred upstroke and loss of the dicrotic notch. Name two causes.
Any 2 of: Air bubbles in line, kink in tubing, clot at catheter tip, compliant tubing, catheter against vessel wall
Your patient has distended neck veins, muffled heart sounds, and hypotension. What type of shock is this and what is the underlying mechanism?
Obstructive shock — cardiac tamponade. Fluid in pericardium restricts ventricular filling
Why might you choose adrenaline over noradrenaline in a patient with cardiogenic shock?
Adrenaline has stronger beta-1 (inotropic) effects — increases contractility and heart rate, useful when you need to support a failing pump
What is the main difference between crystalloids and colloids?
Crystalloids contain small molecules that move freely across membranes (e.g. saline, Hartmann's). Colloids contain larger molecules that stay in the vascular space longer (e.g. albumin)
ST elevation in leads V1–V4 indicates ischaemia in which coronary territory and which vessel?
Anterior wall — Left Anterior Descending (LAD) artery
An underdamped arterial waveform will do what to systolic and diastolic readings?
Overestimate systolic BP (overshoot), underestimate diastolic BP (but MAP remains relatively accurate)
A patient has cold, clammy peripheries, elevated JVP, and hypotension following a large anterior STEMI. What type of shock is this?
Cardiogenic shock
What is the main risk of running vasopressors through a peripheral IV line?
Extravasation causing tissue necrosis
What is the atmospheric pressure at MSL?
760mmHg
How many small squares on an ECG equal one second?
5 large squares or 25 small squares
Before inserting a radial arterial line, what test can be performed to check collateral circulation, and what are you assessing?
Modified Allen's test — assessing ulnar artery patency to ensure hand perfusion if radial artery is compromised
In neurogenic shock, why does the patient have bradycardia and hypotension instead of tachycardia?
Loss of sympathetic tone — the body can't mount a compensatory tachycardia response
Vasopressin works differently to noradrenaline. What receptor does it act on?
V1 receptors (causes vasoconstriction without using the adrenergic system)
How much FiO2 delivery does a Laerdal BVM provide to a spontaneously breathing patient with a PEEP valve, when they are hyperventilating?
FiO2 0.44 !