Here is a flyer for the upcoming Mentoring & Art in Emergency Medicine evening on the 6th July 2017.
If you have forgotten? Feel free to check your assigned mentor / mentees on the Mentorship Program webpage (under the education tab), and encourage them to attend.
The post Mentoring & Art in Emergency Medicine evening 6th July 2017 appeared first on Charlie's ED.
An 82 year old man presents with compensated shock. He has HHS , acute on chronic renal failure, pseudohyponatraemia, hyperkalaemia (total body depletion) Causes: MI, infection, diuretics, CVA, PE Diagnostic Criteria: serum osmolarity > 320mosmol/L serum glucose > 33mmol/L profound … Continue reading
The following ECG is from a patient who presented with atypical right sided chest pain.
|Click to enlarge|
- Ventricular rate ~54 bpm
- Based on QRS R-R interval best seen in left precordial leads
- Unable to accurately visualise atrial activity
- Regular ventricular rate
- Rhythm indeterminate
- High frequency high amplitude interference
- Relative sparring of lead aVR
- Frequency ~30 Hz
- Baseline wander
Troubleshooting artefactThere are multiple factors that can generate artefact during the ECG recording / printing process including:
- Uninterpretable ECG due to significant interference and baseline wander
- Patient factors
- Implanted devices
- PPM - Pacing Spikes
- Nerve stimulators
- Movement disorders e.g. Parkinson's, essential tremor
- Muscle tremor / activity can be related to pain, hypothermia etc.
- Habitus - very thin or obese patients, paediatric patients
- Poor pad contact due to hair
- Poor pad contact due to moisture - sweating, immersion etc.
- Lead factors
- Poor pad contact
- Pad misplacement
- Damaged lead or lead connection
- ECG Machine Factors
- Inappropriate settings of gain or filtering modes
- Electrical artifact from power supply
- Printing factors
- Low ink
- Print head tracking
- Paper alignment
- External factors
- Interference from surrounding electronic devices. Relatively rare using newer ECG machines and environmental interference is usually compounded by incorrect machine filter settings.
An awareness of these factors and a systemic approach to addressing each point in the recording process, from patient to printer, is important in addressing recording problems such as artifact and lead mal-positioning.
What happened ?
Our patient had an implantable neuro-stimulator which was the source of the interference.
He was able to de-activate the device to allow an ECG to be recorded, below:
|Click to enlarge|
Complete resolution of artefact with an interpretable ECG.
References / Further Reading
- Chan TC, Brady WJ, Harrigan RA, Ornato JP, Rosen P. ECG in Emergency Medicine and Acute Care. Elsevier Mosby 2005.