Station - Instructions for candidate
You are an intern in the Emergency Department of a Perth teaching hospital.
Ella Sadler, a 24-year-old retail assistant, has been brought in by ambulance after collapsing in her bathroom this morning. She is on a monitored bed and feels well apart from nausea. The ambulance handover, her ECG and her first bloods are printed on your sheet. The nurse can answer brief questions about her.
| Ambulance handover | Witnessed collapse with about 20 seconds of unresponsiveness, no warning, no jerking, no incontinence, full recovery within a minute; bruised left elbow. Four days of vomiting and diarrhoea, minimal intake. Medicines: ondansetron 8 mg three times daily started two days ago (GP); escitalopram 10 mg daily started two weeks ago. No allergies. HR 70, BP 104/66 mmHg, RR 16, SpO2 99% on room air, temperature 36.9 C, GCS 15, glucose 5.4. |
|---|
Results provided:
12-lead ECG on arrival
| Item | Value | Reference range |
|---|---|---|
| Rate | 70 /min | 60-100 /min |
| Rhythm | Sinus rhythm, regular | Sinus |
| Axis | Normal (+45 degrees) | -30 to +90 degrees |
| P waves and PR interval | Normal P waves; PR 150 ms | 120-200 ms |
| QRS duration and morphology | 88 ms; normal morphology; no Brugada pattern; no delta wave | <120 ms |
| ST segments | Isoelectric | Isoelectric |
| T waves | Broad, low-amplitude and notched in V2-V5; a small U wave in V3 | Upright, normal contour |
| QT and corrected QT | QT 560 ms; RR 860 ms; corrected (Bazett) 540 ms | Corrected QT <460 ms (female) |
Recorded on arrival; a rhythm strip from the ambulance during transport showed sinus rhythm only.
Bloods on arrival
| Item | Value | Reference range |
|---|---|---|
| Potassium | 3.3 mmol/L | 3.5-5.2 mmol/L |
| Magnesium | 0.60 mmol/L | 0.70-1.10 mmol/L |
| Sodium | 136 mmol/L | 135-145 mmol/L |
| Corrected calcium | 2.25 mmol/L | 2.10-2.60 mmol/L |
| Urea and creatinine | 9.2 mmol/L; 88 umol/L | 2.5-8.0 mmol/L; 45-90 umol/L |
| Glucose | 5.4 mmol/L | 4.0-7.8 mmol/L |
| Beta-hCG | Negative | Negative |
Taken on arrival before any treatment.
Your tasks are to:
- Interpret the ECG and blood results provided.
- State your most likely diagnosis and differential diagnoses to the examiner.
- Outline your immediate management plan to the examiner.
- The examiner will ask you two questions at the end.
- You do NOT need to take a history or examine the patient; the nurse can answer brief questions and will carry out your instructions.
- The patient is on a cardiac monitor; further results are available from the examiner on request.
This is a 10-minute station, with 2 minutes of reading time.