Cardiac causes of cardiac arrest

Learning outcomes This lecture should enable you to: describe the different types of ACS explain how to recognise and assess an ACS list the relevant immediate treatment for each type of ACS discuss how to recognise and respond to other cardiac conditions that may cause cardiac arrest

Initial approach ABCDE approach Airway Breathing Circulation Disability (including Drugs/Diabetes/Documentation) Exposure

Acute coronary syndromes Clinical syndromes caused by the same disease process: unstable angina non-ST-elevation myocardial infarction ST-elevation myocardial infarction

Risk Stratification

Unstable Angina Presenting historyNormal ECG Non specific abnormalities of the ECG ST Depression on ECG Consistently negative or small rise in troponin NSTEMI Presenting historyNormal ECG Non specific abnormalities of the ECG ST Depression on ECGTroponin release STEMI Presenting historyST elevation on ECG New left bundle branch block Troponin release

Immediate treatment for all acute coronary syndromes ABCDE approach aspirin 300 mg orally (crush/chew) nitrate (GTN tablet or patients own spray) fentanyl/morphine oxygen - if hypoxic or signs of shock (SpO 2 <94% or no measurement available) consider other antiplatelet medication

Clinical setting and history I You receive a call from a nurse Sasking you to review urgently a 55-year-old woman with a 3-hour history of central chest pain BJasvinder self-presented and is normally well AShe looks unwell, clammy and anxious RPlease assess her immediately Case 1

Case 1 (continued) Airway Assessment – patient talking – complaining of severe central chest pain, radiating to neck and down left arm There is no evidence of airway obstruction Treatment/Action – high flow oxygen started Response – no change

Case 1 (continued) Breathing Assessment – R - RR 20 min -1 – A - normal, symmetrical chest expansion, breath sounds and percussion note – T – trachea normal – E – normal effort – S - SpO 2 100% on high flow oxygen Her SpO 2 indicates that her oxygen concentration should be reduced Treatment – inspired oxygen concentration reduced Response – SpO 2 97% using 3 L min -1 via nasal prongs

Case 1 (continued) Circulation Assessment – regular radial pulse, rate 100 min -1 – BP 110/65 mmHg, CRT <2 s – normal heart sounds – ECG monitor request 12 lead ECG (next slide) – bloods including troponin Treatment/Action – venous/vascular access – aspirin to chew – sublingual nitrate/GTN – IV fentanyl/morphine

Case 1 (continued) Circulation Assessment – regular radial pulse, rate 100 min -1 – BP 110/65 mmHg, CRT <2 s – normal heart sounds – ECG monitor – request 12 lead ECG – venous/vascular access – bloods including troponin Treatment/Action – aspirin to chew – sublingual GTN – IV fentanyl/morphine Response – reduces chest pain – first troponin normal – ECG - ST Depression – repeat troponin later With the history and findings the most likely cause is an ACS

Case 1 (continued) Disability Assessment – alert and anxious – pupils equal, react to light – blood glucose 7.0 mmol L -1 Treatment/Action – nil Response – no change Exposure Assessment – no bleeding or rashes – temperature 36.6 ˚C Treatment/Action – nil Response – no change Plan: Requires urgent cardiology review (?Unstable Angina/NSTEMI) awaiting repeat troponin - consider oral anti-platelets and anticoagulation also pain relief and myocardial protection

Clinical setting and history I You are called to assess a patient by a colleague SA 63 year old gentleman with a 1-hour history of central chest heaviness and shortness of breath BBill was sitting at his desk when the pain started, similar to his angina, but unrelieved by GTN spray AHe looks unwell, clammy and anxious RPlease assess him immediately Case 2

Case 2 (continued) Airway Assessment – patient talking – complaining of severe central chest pain (heaviness) – no evidence of airway obstruction Treatment/Action – high flow oxygen started Response – no change

Case 2 (continued) Breathing Assessment – R - RR 23 min -1 – A - bilateral basal crackles, symmetrical chest expansion – S - SpO 2 not able to be recorded on high flow oxygen – T - normal – E - increased effort Treatment – continue high flow oxygen Response – SpO 2 remains unrecordable Inability to record SpO 2 indicates that high flow oxygen concentration should be used

Case 2 (continued) Circulation Assessment – Cool, clammy peripheries, – regular radial pulse, rate 55 min -1 – BP 80/65 mmHg, (right = left arm) – CRT 4 s – normal heart sounds – request 12 lead ECG Treatment/Action – aspirin to chew – IV access obtained – blood samples taken including troponin – IV fluid commenced – IV fentanyl/morphine – sublingual GTN Expert help - cardiology/resuscitation team With the history and findings the most likely cause is an ACS

Case 2 (continued) Circulation Response – troponin result - raised – IV pain relief reduces chest pain – ECG (Inferior STEMI) – Plan for reperfusion With the history and findings the most likely cause is a STEMI

Case 2 (continued) Disability Assessment – alert and anxious – pupils equal, react to light – blood glucose normal Treatment/Action – nil Response – no change Exposure Assessment – clammy, sweating and pale – ankle oedema – no bleeding or rashes – Temperature 36.3 ˚C Treatment/Action – nil Response – no change Plan: STEMI – emergency reperfusion

Access to emergency reperfusion

Other cardiac causes of cardiac arrest in any cardiac arrest look for evidence of the cause not all cardiac arrests are due to ACS other causes may be ‘structural’ or ‘electrical’ some are inherited, some acquired, some congenital

Examples of other cardiac causes ConditionNatureCausation Severe aortic stenosisStructuralMostly acquired Sometimes congenital Hypertrophic cardiomyopathy StructuralInherited High-grade AV blockElectricalMostly acquired Occasionally congenital Long QT syndromeElectricalInherited, but… there are other causes of a long QT interval Anomalous coronary anatomy StructuralCongenital

Long QT syndrome

Other cardiac causes: preventing cardiac arrest be alert for warning symptoms (e.g. unexplained syncope) arrange urgent specialist assessment and treatment (including genetic family) with inherited conditions, don’t forget the family

Any questions?

Summary recognise the different presentations of ACS use the ABCDE approach start appropriate immediate treatment arrange immediate PPCI when appropriate be aware of other cardiac causes of arrest requiring different management

Advanced Life Support Level 2 Course Slide set All rights reserved © Australian Resuscitation Council ( June 2016 )