Prehospital ECGs
Decoding the Heart's Rhythm: Understanding Prehospital ECGsPrehospital ECGs interpretation is a critical skill in identifying time-sensitive cardiac emergencies such as STEMI, life-threatening arrhythmias, heart block and acute coronary syndromes. In the prehospital environment, early recognition of ischaemia, conduction abnormalities and electrical instability can directly influence patient pathways, including pre-alert decisions, reperfusion activation and destination planning. Accurate, systematic analysis of the 12-lead ECG, combined with clinical assessment and symptom correlation, supports timely intervention and improved patient outcomes.
This PreHospitalHub section explores prehospital ECGs interpretation from a frontline perspective, emphasising structured approaches to rhythm analysis, axis assessment, interval measurement and ST-segment evaluation. It also examines common ECG mimics, dynamic and evolving changes, electrolyte-related abnormalities, and the importance of serial ECG monitoring. Designed for healthcare professionals working across prehospital, emergency and urgent care settings, these resources aim to strengthen diagnostic confidence, reduce interpretation errors and enhance safe, evidence-informed decision-making in cardiac presentations.
ECG Essentials
ECG Intervals & Segments
ECG Diagnosis
ECG Pharmacology
Prehospital ECGs – FAQs
Frequently Asked Questions about Prehospital ECGs in Paramedic Practice
Why is ECG interpretation important in prehospital care?
Early ECG interpretation allows rapid identification of time-critical conditions such as STEMI, life-threatening arrhythmias and conduction abnormalities, enabling timely pre-alert and definitive management.
What are the key ECG findings in STEMI?
STEMI is typically identified by ST-segment elevation in anatomically contiguous leads, often with reciprocal changes. Prompt recognition supports rapid reperfusion pathways.
How can paramedics recognise life-threatening arrhythmias?
Life-threatening arrhythmias may include ventricular tachycardia, ventricular fibrillation, high-grade AV block and extreme bradycardia. Clinical correlation with haemodynamic stability is essential.
What are common ECG mimics of STEMI?
Pericarditis, early repolarisation, left bundle branch block (LBBB) and left ventricular hypertrophy (LVH) can produce ECG changes that resemble STEMI, requiring careful interpretation.
When should a 12-lead ECG be performed?
A 12-lead ECG should be performed in patients presenting with chest pain, syncope, palpitations, shortness of breath, unexplained hypotension or suspected cardiac events.
Prehospital ECGs – CPD Reflection Prompts
Reflective practice strengthens ECG interpretation skills, improves clinical reasoning and supports safer decision-making in time-critical cardiac presentations. Use the prompts below to guide reflection on a recent ECG assessment undertaken in the prehospital setting.
Reflect on a recent ECG you have interpreted and consider the following:
- jWhat was the patient’s presenting complaint and clinical context?
- jWhat systematic approach did you use to interpret the ECG (rate, rhythm, axis, intervals, ST/T changes)?
- jWere there any time-critical findings such as STEMI, high-grade block or ventricular arrhythmia?
- jDid the ECG correlate with the patient’s symptoms and observations?
- jDid you perform serial ECGs, and did any dynamic changes occur?
- jWere there potential mimics (e.g. pericarditis, LVH, LBBB, electrolyte imbalance)?
- jWhat went well in your interpretation and clinical decision-making?
Consider recording this reflection in your CPD portfolio or ePortfolio, such as the PrehospitalHalo CPD Log, using a recognised framework like the Gibbs Reflective Cycle or What? So What? Now What?. Structured reflection supports deeper clinical insight, enhances self-awareness, and helps translate experience into improved practice.
Documented reflections like this provide evidence of ongoing learning and can support annual CPD requirements, in line with expectations set by professional and regulatory organisations such as the HCPC, HPAC, UKREMT, Qualsafe, HEE, and many others. Maintaining clear, well-structured CPD records is an essential part of demonstrating safe, effective, and reflective practice as a healthcare professional.
