The monitors and echo station: format and timing
Stem
You are at the door of the interpretation of monitors and echocardiograms station with 4 minutes to read the stem. Inside, a facilitator will play three separate scenarios: a physiologic monitor case, a TEE or POCUS case, and a combined case. The first case description reads: a 52-year-old man, 80 kg, in the sitting position for a posterior fossa craniotomy under general anesthesia. The monitor recording plays:
Question
How will you approach the three scenarios, and what do you say for this first one?
Ideal answer
What the monitor showed: end-tidal CO2 fell from 38 to 12 mmHg over four breaths with the waveform shape preserved; heart rate and SpO2 had not yet changed.
I know the three questions before the clip starts, because the ABA publishes them. The monitor case asks what changed and the most likely diagnosis. The TEE or POCUS case asks me to describe the findings, give the most likely diagnosis and my management plan. The combined case shows the monitor first, then echo images from the same patient, and asks for the monitor changes, the echo findings and the diagnosis.1 Each scenario plays once and I cannot go back, so I watch the whole recording before I speak.1 Then I answer the questions in the order they were asked. For this clip: "End-tidal CO2 has fallen from 38 to 12 over four breaths with a preserved waveform shape; heart rate and saturation have not changed yet." Then the diagnosis: "In a sitting craniotomy, the most likely diagnosis is venous air embolism; a disconnect would have flattened the waveform." If time remains, I add the first action: tell the surgeon to flood the field and go to 100% oxygen.
Breaking down the answer
- Know the three scenario types — one monitor-only case of about 2 minutes, one TEE-or-POCUS-only case of about 1.5 minutes and one combined case of about 2.5 minutes, each with roughly 60 seconds to answer, shown on a countdown timer.1 The scenarios are unrelated to each other, so I reset my differential between them.
- The monitor case changes in front of me — the change happens while the recording plays, or I see two recordings, before and after.1 I name the parameter and the direction before the diagnosis; the sample answer key lists the rhythm change from sinus to junctional and the hypotension before the diagnosis, loss of AV synchrony.1 The display follows the ABA's label chart, including TOF count and ratio.
- The echo case is the only one that asks for management — the sample key for aortic stenosis lists findings, the diagnosis, then fluid, a vasopressor, avoiding tachycardia and referral.1 I name the view first, then the chamber or valve, then the abnormality.
- The combined case is one story — the monitor raises the question and the echo answers it; the sample pairs hypertension, tachycardia and ST depression with new septal and anterior wall motion abnormalities on a transgastric short-axis view, so the diagnosis is demand ischemia.1 I answer all three parts and give one unifying diagnosis.
- Know the scope — 11 standard TEE views and the POCUS heart, lung, abdomen and gastric views, two-dimensional with or without color and lung M-mode, no pulsed-wave or continuous-wave Doppler; quantitative neuromuscular monitoring and fetal heart rate testing start in 2026, and airway ultrasound structures and bladder volume in 2027.2
- Nobody helps — the facilitator reads the questions, is not a physician, adds nothing, and an examiner scores the recording remotely.1 Published practice modules mirror this one-way format.3
Follow-up question
The combined scenario: the monitor shows a falling blood pressure and a rising central venous pressure, and then a transgastric short-axis view shows a small, hyperdynamic left ventricle with a dilated right ventricle and a flattened septum. What do you say?
Follow-up answer
The trap is answering only half. I give the three answers in the order asked. The monitor: hypotension with a rising CVP, so high right-sided filling with low output. The echo: transgastric mid-papillary view, a dilated right ventricle with a septum flattened into a D-shaped, underfilled, vigorous left ventricle. The diagnosis: acute right ventricular failure from a pressure load, pulmonary embolism or air. With the seconds left I add the action: 100% oxygen, norepinephrine and an inotrope, no fluid loading of a full right heart, and call for help. If the image is poor, I say what I can see, name what I cannot exclude, and still give one diagnosis; that scores better than an invented finding.
Pitfalls that cost points
- Talking over the recording and missing the second half of the change.
- Diagnosing before describing; the finding is the scored item.
- Skipping the management plan in the echo-only case, the one scenario that asks for it.
- In the combined case, describing the monitor and the echo but never joining them into one diagnosis.
- Forgetting the case description and answering as if the patient were healthy.
Rapid-fire
Q: How long is each scenario? A: About 2 minutes for the monitor case, 1.5 for the echo case and 2.5 for the combined case, each with about 60 seconds to answer;1 the whole station is up to 8 minutes after a 4-minute stem read.4
Q: Will a recording replay if I ask? A: No. Each scenario plays once, and once I move on I cannot go back.1
Q: Does the facilitator respond to my answer? A: No. The facilitator is not a physician and gives no extra information; an examiner scores the recording remotely.1
Q: If the echo case shows more than one image, are they related? A: Yes; assume they come from the same patient.1
Q: What if I cannot identify the echo view? A: I describe the structures I can see and the abnormality, then name the most likely view; a correct finding beats silence.
Numbers to know
| Item | Value |
|---|---|
| Station length | Up to 8 minutes; 7 stations in all4 |
| Stem read | 4 minutes before entering |
| Warning bell | 2 minutes remaining, at 6 minutes |
| Scenarios per station | 3: monitor only, TEE or POCUS only, combined1 |
| Scenario length | ~2 min monitor, ~1.5 min echo, ~2.5 min combined1 |
| Answer window | ~60 seconds per scenario1 |
| Questions | 2 monitor, 3 echo (with management), 3 combined1 |
| Echo views in scope | 11 TEE, 5 POCUS cardiac2 |
| Coming in 2027 | Airway ultrasound structures, bladder volume2 |
| New monitor items | Quantitative neuromuscular blockade and fetal heart rate, testing from 20262 |
Links
- OSCE day: stations, timing, who is in the room, Monitor atlas: perioperative cardiac events, Monitor atlas: perioperative respiratory events, Capnography: waveforms and sudden loss of ETCO2
- Atlas: The 11 TEE views; The 5 POCUS cardiac views
- ABA public sample OSCE (2023) and the APPLIED Examination OSCE content outline (current edition)
Sources
- 1.OSCE Example Scenarios · ABA, 2023 · theaba.orgInterpretation of Monitors and Echocardiograms: three scenario types, timings, the exact questions and sample answer keys.
- 2.OSCE Content Outline · ABA · theaba.org
- 3.Modules for the Technical Skills Section of the OSCE Component of the American Board of Anesthesiology APPLIED Examination · MedEdPORTAL (PubMed Central), 2019 · pmc.ncbi.nlm.nih.govPractice modules built to mirror ABA timing; not an ABA description of the live station.
- 4.APPLIED Exam Manual · ABA, 2026 · theaba.orgRevised July 2026; OSCE timing, signals and room personnel.
Facts on this page were checked against these sources on Oct 14, 2026. Guidelines change; confirm doses against current institutional protocols.