paramedicine theory medical

what are the worst case scenarios of ACS using the acronym TAP MAP

tension pneumothorax, ACS, pulmonary embolism, mediastinitis, aortic dissection, pericardial tamponade

pathophysiology of coronary artery disease?

a narrowing and stiffening of the arteries that perfuse the myocardium. It is caused by atherosclerosis. this causes an imbalance in oxygen supply and oxygen demand.

other names for coronary artery disease

heart disease or coronary heart disease

name some risk factors for ACS and an acronym to help

HTN, age, male

CHAM FOLDS is an acronym you can use.

define ischaemia

restricted blood flow to a part of the body

define injury in the context of ACS

tissue has suffered damage due to ischaemia. if reperfused it can heal.

define infarction

myocardial death due to prolonged ischaemia

define stable angina

reproduced by exercise, eating and stress and is relieved with rest and without recent change in frequency or severity of activity that produce symptoms

what is needed to diagnose acute myocardial infarction?

clinical presentation, ECG findings and biomarkers (we don't have these in the field yet).

what does STEMI stand for?

ST segment elevated myocardial infarction

what is cardiogenic shock?

primary cardiac disorder that results in both clinical and biochemical evidence of tissue hypoperfusion

characteristics of ACS pain

radiating, be diffuse and not pinpoint, non aggravating and non relieving, feels like a previous cardiac episode.

pharmacology of aspirin

causes irreversible inhibition of cyclooxygenase necessary for thromboxane A2 synthesis which is responsible for platelet aggregation and vasoconstriction

common dose for aspirin

300mg

common dose for GTN spray

400mcg

what is the pharmacology of GTN

promotes vascular smooth muscle relaxation which causes venous and arterial dilation reducing preload and afterload

this reduces oxygen demand, systolic diastolic and MAP, provides coronary artery dilation

true or false, electrical activity within the heart can only ever begin at the SA node or AV node

false

the PR interval is measured from the...

end of the p wave to the end of the QRS

when a sinus rhythm has a QRS complex of 0.12seconds or greater this is an abnormality called

aberrant conduction or wide QRS

what occurs during diastole?

relaxation and filling

what occurs during systole?

contraction and blood ejection

how long does the cardiac cycle last?

0.8 seconds

What is cardiac output?

amount of blood pumped by each side of the heart in one minute

Cardiac output formula

heart rate multiplied by stroke volume

what is stroke volume

the volume of blood pumped by each ventricle in one contraction

what electrolytes are mainly involved with electrophysiology?

sodium and potassium

what does sodium and potassium do with regards to electrophysiology?

the movement of these electrolytes causes changes to electrical balance causing an electrical current to form

what role does calcium play in electrophysiology?

after depolarisation occurs calcium enters cells to allow for mechanical contraction of the heart

what is the rate of the SA node?

60-100bpm

what is rate of the AV node?

40-60bpm

what is the rate of the ventricles?

20-40 bpm

define automaticity

cells in the heart generating their own electrical activity

where does the sympathetic nervous system affect the heart?

atria, junction and ventricles

how does the sympathetic nervous system affect the heart?

increase HR, increase conduction velocity, increase contractility, increase irritability

what parts of the heart do parasympathetic nervous system affect?

atria

how does the parasympathetic nervous system affect the heart?

slow the atrial firing rate, slow conduction, decrease contractility, decrease irritability

what nerve is part of the parasympathetic nervous system?

vagus nerve

what happens when the vagus nerve is stimulated

it can slow the atrial firing rate, slow conduction, decrease contractility, decrease irritability

name the four pacemaker sites

sinus, atrial, junctional and ventricular

what number must I remember for the 300 method for calculating the rate of an ECG strip?

300, 150, 100, 75, 60, 50, 43, 38, 33

what defines an atrial rhythm?

abnormal p waves

what defines junctional rhythms?

inverted the p waves/short PR interval due to retrograde depolarization

what indicates ventricular rhythms?

wide QRS complexes

what is a sinus dysrhythmia

irregular pattern but still a sinus rhythm

name two types of supraventricular tachycardia

atrioventricular nodal reentrant tachycardia (AVNRT) or atrioventricular re-entry tachycardia (AVRT)

how does chronotropy impact cardiac conduction?

increase heart rate

how does dromotrophy impact cardiac conduction?

increase conduction velocity

how does inotropy impact cardiac conduction?

increase contractility

define contractility

describes the relative ability of the heart to eject a stroke volume (SV) at a given prevailing afterload and preload

define irritability

a state of increased sensitivity to stimuli

how do atrial p waves present?

flat, notched, peaked, saw-toothed and di-phasic

name three causes for variant angina

1. prinzmetal's angina

2. arterial dissection

3. secondary causes e.g. fever, anemia etc.

what is an aortic dissection

a split in the media of the aortic wall

what causes an aortic dissection?

high pressure caused by blood movement from the contraction of the heart

what are some ways to recognise aortic dissection?

ripping or tearing pain radiating through to back, sudden onset, different blood pressures in the arms

what is a pulmonary embolism

the lodging of a clot in the pulmonary arteries.

how do you recognise a pulmonary embolism?

sharp, locased chest pain, aggravated by breathing, unexplained SOB, poor SpO2, hemoptysis , signs and risk factors for DVT, no adventitious sounds on auscultation

what is a tension pneumothorax

the presence of air in the pleural space - a collpased lung

how do you recognise a tension pneumothorax

chest pain on affected side, pain aggravated by inspiration, decreased breath sounds on effective side, trauma, JVD and tracheal deviation, subcutaneous emphysema (gas bubbles under skin), hypotensive, ALOC

what is pericardial tamponade

accumulation of fluid in the pericardial sac

what happens to the ventricles in pericardial tamponade?

fluid impedes ventricular filling leading to decreased CO

how do you recognise pericardial tamponade?

chest pain relieved/aggravated with lean and lay test, hypotension, JVD and muffled heart sounds, fever, history of trauma

what are the three elements of the beck triad

hypotension, JVD, muffled heart sounds.

what is mediastinitis

a life threatening infection of the mediastinum

what is the likely cause of mediastinitis

thoracic surgery and esophageal rupture from persistent vomiting

how to recognise mediastinitis

signs of sepsis, fever, constant vomiting, recent chest surgery

what is costochondritis

inflammation of the costochondral junctions where the ribs meet the sternum

signs of costochondritis

localised pain, aggravated by palpation, sharp and pleuritic, pain changes with position coughing and inspiration, due to overuse or trauma

what is reflux

reflux of gastric contents back into the esophagus

signs of reflux

burning, radiating up neck, epigastric region, due to large meals sometimes, nausea, regurgitation or burping, relieved by antacids

define anxiety

a psychological disorder that can often present with chest pain and hyperventilation

what are some signs of anxiety

acute onset, pleuritic chest pain, SOB, trembling, shaking, altered sensation, distressed and anxious

what muscles could be responsible for chest pain?

intercostal muscles and the pectoris major

what are some signs of muscular chest pain?

localised, sharp in nature, aggravated by movement, palpation, coughing, inspiration, caused by trauma/exertion

what is pneumonia

infection and inflammation of the lung parenchyma resulting in impaired gas exchange

what are some signs of pneumonia

localised chest pain, pleuritic, productive cough, fever, SOB with coarse crackles

what is pleurisy

inflammation of tissues that line the lungs and chest cavity (parietal and visceral). this makes the two layers rub together. caused by an underlying bacterial or viral condition

what are some signs of pleurisy?

acute onset, localised to side, pleuritic in nature, friction rub heard on auscultation, fever, shoulder pain

what is pericarditis

inflammation of the pericardium, the membrane that surrounds the heart

what are some signs of pericarditis?

sharp, pleuritic pain, aggravated by laying back and relieved by sitting up, global ECG changes, fever

what can pericarditis lead to ?

cardiac tamponade

what is pancreatitis

inflammation of the pancreas often associated with excessive alcohol

signs of pancreatitis

severe epigastric pain that can radiate to chest and back, aggravated on palpation of the epigastric region, alcohol consumption, N/V, fever

what is oesophageal spasm

chest pain associated with the spasming and contracting of the oesophagus

signs of oesophageal spasm

sudden chest pain, feeling of choking, difficulty swallowing, occurs after eating

what is shingles

a virus that can cause painful rash over the skin

what are some signs of shingles

pain along dermatomes, paresthesia, rash evident

are first degree heart blocks regular or irregular?

regular mostly - depends on the underlying rhythm

are 2nd degree type 1 heart blocks regular or irregular?

irregular

are 2nd degree type 2 heart blocks regular or irregular?

irregular

are 3rd degree heart blocks regular or irregular?

regular

what is an acronym that is used for other ACS differentials?

CRAMPPPSS

what does the CRAMPPPSS stand for?

costochondritis, reflux, anxiety, muscular, pulmonary (infection/inflammation), pericarditis, pancreatitis, spasm of the esophagus, skin

what is shock?

failure of the circulatory system to adequately provide oxygen to organs and the peripheral tissue.

how does the body attempt to maintain perfusion status

CO= HR x SV

what factors result in hypoperfusion

blood flow, blood volume, peripheral resistance

define cardiogenic shock

inadequate CO

define distributive shock

loss of vasomotor resistance in arterioles and venules

give two examples of distributive shock

anaphylaxis and sepsis

define obstructive shock

from impedance to flow in major vessels