Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Cardiovascular
| Question | Answer |
|---|---|
| Automaticity | The ability of pacemaker cells to spontaneously generate electrical impulses without external stimulation |
| Resting Membrane Potential | The electrical difference across a cardiac cell membrane at rest (~-90mV in ventricular myocytes) |
| Threshold Potential | The critical voltage (~-70mV in myocytes) that must be reached to trigger an action potential |
| Depolarization | Electrical activation of a cell as positive ions rush in, making the membrane potential less negative |
| Repolarization | Electrical recovery phase where the membrane returns to its negative resting state (mainly via K+ efflux) |
| Pacemaker Cell Phases | Phase 4 (spontaneous depolarization), Phase 0 (rapid depolarization at threshold), Phase 3 (repolarization) |
| Myocyte Action Potential Phases | Phase 4 (resting), Phase 0 (Na+ influx), Phase 1 (early repolarization), Phase 2 (plateau, Ca2+ influx), Phase 3 (K+ efflux repolarization) |
| SA Node | Primary pacemaker of the heart, located in the right atrium, highest intrinsic firing rate (60-100bpm) |
| AV Node | Delays conduction between atria and ventricles to allow ventricular filling; secondary pacemaker (40-60bpm) |
| Bundle of His | Connects the AV node to the ventricles, splitting into right and left bundle branches |
| Purkinje Fibres | Network conducting impulses rapidly through ventricular myocardium for coordinated contraction (<20bpm intrinsic rate) |
| Gap Junctions | Protein channels connecting cardiac myocytes allowing rapid spread of electrical signals |
| Electromechanical Coupling | The link between electrical depolarization/repolarization and mechanical contraction/relaxation |
| Isoelectric Line | The ECG baseline; represents no net electrical movement |
| P Wave | Represents atrial depolarization; normal <120ms, <2.5mm, upright in I, II, aVF |
| PR Interval | Time from start of P wave to start of QRS; normal 0.12-0.20s; reflects AV nodal delay |
| QRS Complex | Represents ventricular depolarization; normal <0.12s |
| J Point | Junction where QRS ends and ST segment begins |
| ST Segment | J point to start of T wave; represents full ventricular depolarization before repolarization begins |
| T Wave | Represents ventricular repolarization; upright in I, II, V3-V6 |
| U Wave | Small deflection after T wave, possibly delayed Purkinje/ventricular repolarization |
| QT Interval | Start of QRS to end of T wave; total ventricular electrical activity duration |
| RR Interval | Peak of one R wave to the next; represents one cardiac cycle, used for heart rate |
| Einthoven's Triangle | Imaginary triangle formed by RA, LA, LL electrodes representing bipolar limb leads I, II, III |
| Lead II | Positive pole at left leg, negative at right arm; aligns with normal depolarization, best for rhythm monitoring |
| Bipolar Leads | Leads I, II, III - compare electrical activity between two electrodes |
| Augmented Leads | aVR, aVL, aVF - unipolar, one electrode vs. calculated reference |
| Precordial Leads (V1-V6) | Chest leads viewing the heart in the horizontal/transverse plane |
| Small Square (ECG paper) | 1mm = 0.04 seconds (time) / 0.1mV (amplitude) |
| Large Square (ECG paper) | 5mm = 0.20 seconds (time) / 0.5mV (amplitude) |
| Rule of 300 | Heart rate method: 300 divided by number of large squares between R waves (regular rhythms) |
| Rule of 1500 | Heart rate method: 1500 divided by number of small squares between R waves (more accurate, regular rhythms) |
| Six-Second Method | Count QRS complexes in 6 sec times 10; best for irregular/slow rhythms |
| Torso (Modified) Limb Placement | Electrodes placed on torso instead of distal limbs to reduce movement artefact |
| Picket Fence Artefact | Repetitive vertical spikes caused by electrode placement too close to a pacemaker |
| Normal Sinus Rhythm | Rate 60-100bpm, regular, upright uniform P waves, normal PR/QRS |
| Sinus Bradycardia | Sinus rhythm, rate less than 60bpm, otherwise normal |
| Sinus Tachycardia | Sinus rhythm, rate greater than 100bpm, otherwise normal |
| Sinus Arrhythmia | Sinus rhythm with irregular R-R intervals, often respiratory-linked |
| Atrial Fibrillation | Irregularly irregular rhythm, no discernible P waves, chaotic atrial activity |
| Atrial Flutter | Regular rhythm, saw-tooth flutter waves, often 2:1 conduction (~150bpm ventricular) |
| Ventricular Tachycardia | Rate greater than 100bpm, wide QRS (greater than 0.12s), P waves absent/dissociated |
| Monomorphic VT | VT with consistent QRS shape/morphology throughout |
| Polymorphic VT | VT with varying QRS shape, size, amplitude (e.g., Torsades de Pointes) |
| Ventricular Fibrillation | Chaotic rhythm, no P waves or QRS, no effective contraction - shockable arrest rhythm |
| Coarse VF | Large-amplitude fibrillatory waves, earlier stage, more responsive to defibrillation |
| Fine VF | Low-amplitude fibrillatory waves, may resemble asystole |
| Pulseless Electrical Activity (PEA) | Organised electrical activity present but no palpable pulse; non-shockable |
| Asystole | Absence of detectable electrical activity; near-flat line; non-shockable |
| 4 Hs (PEA/arrest causes) | Hypoxia, Hypovolaemia, Hypo/Hyperkalaemia, Hypothermia |
| 4 Ts (PEA/arrest causes) | Tension pneumothorax, Tamponade, Toxins, Thrombosis |
| Perfusion | Delivery of oxygenated blood to tissues to meet metabolic needs |
| Cardiac Output (CO) | Volume of blood pumped per minute; CO = HR x SV (normal 4-8 L/min) |
| Stroke Volume (SV) | Volume of blood ejected per heartbeat (~70mL); SV = EDV minus ESV |
| Preload | Volume of blood filling ventricles before contraction (venous return dependent) |
| Afterload | Resistance the ventricle must overcome to eject blood |
| Contractility | Force of myocardial contraction, influenced by calcium availability |
| Frank-Starling Mechanism | Greater ventricular stretch (preload) leads to greater contractile force and greater stroke volume |
| Mean Arterial Pressure (MAP) | Average arterial pressure per cycle; MAP = DBP + one third (SBP-DBP); normal 70-100mmHg |
| Systemic Vascular Resistance (SVR) | Total peripheral resistance from vasoconstriction/dilation; MAP = CO x SVR |
| Baroreceptors | Pressure sensors in carotid sinus/aortic arch detecting BP changes |
| Compensated Perfusion | Body maintains BP/perfusion despite compromise (tachycardia, cool/pale skin) |
| Decompensated Perfusion | Compensatory mechanisms fail - hypotension, weak pulses, altered consciousness |
| ACVPU | Scale for conscious state: Alert, Confused, Voice, Pain, Unresponsive |
| Capillary Refill Time (CRT) | Time for skin colour to return after blanching; normal less than 2 seconds |
| Myocardial Oxygen Supply (factors) | Coronary blood flow, oxygen content of blood, duration of coronary perfusion |
| Myocardial Oxygen Demand (factors) | Heart rate, ventricular wall tension, contractility |
| Myocardial Ischaemia | Oxygen demand exceeds supply, impairing contraction and electrical stability |
| Coronary Perfusion Timing | Majority of coronary blood flow occurs during diastole |
| Tachycardia (O2 balance) | Increases demand and reduces supply by shortening diastole - double-edged effect |
| SOCRATES | Symptom analysis framework: Site, Onset, Character, Radiation, Associations, Time course, Exacerbating/relieving factors, Severity |
| Red Flags (cardiac) | Chest pain at rest, syncope on exertion, dyspnoea at rest, hypotension, altered consciousness, etc. |
| Jugular Venous Pressure (JVP) | Indirect measure of right atrial/central venous pressure; elevated suggests right heart failure/overload |
| Fine Crackles | High-pitched, velcro-like sounds in late inspiration; suggest pulmonary oedema/fibrosis |
| Coarse Crackles | Lower-pitched, bubbling sounds; from larger airway fluid, can be cleared by coughing |
| Wheeze | High-pitched continuous sound from narrowed airways, usually expiratory |
| Rhonchi | Low-pitched snoring/gurgling sound from secretions in larger airways |
| Vesicular Breath Sounds | Normal lung sounds, continuous, louder/longer on inspiration |
| Bronchial Breath Sounds | Louder, hollow sounds normally heard centrally; abnormal if heard peripherally (consolidation) |
| Pharmacokinetics | What the body does to a drug (absorption, distribution, metabolism, excretion) |
| Pharmacodynamics | What the drug does to the body |
| Bioavailability | Extent/rate a drug enters systemic circulation |
| First Pass Metabolism | Metabolism of orally administered drugs in gut/liver before reaching systemic circulation |
| Half-Life | Time for drug plasma concentration to reduce by 50% |
| 6 Rights of Medication | Right patient, medication, dose, time, route, documentation |
Created by:
gtrout
Popular Paramedic/EMT sets