Case: inferior wall STEMI from door to discharge

The case

0800 A 68-year-old arrives with two hours of crushing substernal pressure that began while resting, with nausea and diaphoresis. Skin cool and damp. Pain 8 out of 10. Heart rate 54, blood pressure 138/84 mm Hg, respirations 20, oxygen saturation 96 percent on room air.

0812 Twelve-lead shows ST elevation in II, III, and aVF with reciprocal depression in I and aVL. A right-sided tracing shows elevation in V4R. Heart rate 52 with occasional pauses on the monitor. Blood pressure 132/80 mm Hg.

0820 After the first sublingual nitroglycerin, blood pressure falls to 78/48 mm Hg, heart rate 50, and the patient becomes lightheaded and gray. Pain still 8 out of 10.

1130 Returns from catheterization with a right femoral sheath site, on bed rest with the leg straight. Reports new dull back discomfort. Heart rate rises from 96 to 112, blood pressure falls from 96/58 to 88/54 mm Hg. Groin dressing dry and intact.

Step 1 · Recognize cues. Which findings at 0800 and 0812 are the cues that matter?

1. Rest pain with diaphoresis and cool skin.
2. Bradycardia with pauses in the presence of an inferior pattern.
3. ST elevation in II, III, and aVF with reciprocal depression, plus elevation in V4R.
4. Oxygen saturation of 96 percent on room air.
5. Respiratory rate of 20. Cues: 1, 2, and 3.

Step 2 · Analyze cues. What do those cues most likely mean together?

1. Anterior wall infarction with early pump failure.
2. Inferior wall infarction from right coronary occlusion, with nodal involvement and probable right ventricular infarction.
3. Pericarditis with a developing effusion.
4. Stable angina provoked by exertion. Analysis: 2.

Step 3 · Prioritize hypotheses. Rank the concerns for the next thirty minutes.

1. Perfusion, because the right ventricle is preload dependent and the pressure has nowhere to fall from.
2. Rhythm, because nodal ischemia is already producing pauses.
3. Pain, because pain drives demand.
4. Reperfusion timing, which runs underneath all three. Priority order: perfusion, rhythm, pain, with the reperfusion clock running throughout.

Step 4 · Generate solutions. Which are appropriate to plan at 0820?

1. Withhold any further nitrate and notify the provider.
2. Position the patient supine and prepare for volume support per order.
3. Keep transcutaneous pacing pads on the patient with the defibrillator at the bedside.
4. Maintain patent intravenous access and continuous monitoring.
5. Give the second nitroglycerin dose on schedule and reassess in five minutes.
6. Raise the head of the bed to 60 degrees for comfort. Solutions: 1, 2, 3, and 4. Options 5 and 6 both lower filling further.

Step 5 · Take action. Place the 0820 actions in order.

1. Stop further nitrate and place the patient supine.
2. Recheck blood pressure, heart rate, and level of consciousness.
3. Notify the provider and read back the volume order.
4. Infuse the ordered volume and stay at the bedside.
5. Reassess pressure, rhythm, lung sounds, and pain. At 1130, in order: assess the site and the distal pulses, recheck pressure and heart rate, notify the provider that back pain accompanies a falling pressure and a rising rate, keep the patient flat with the leg straight, and maintain access while the ordered study is arranged.

Step 6 · Evaluate outcomes. What tells you it worked?

• Systolic pressure recovers and holds without a further fall on repeat.
• Pain score falls and stays down without another nitrate dose.
• Rhythm holds without new pauses or progression of block.
• Puncture site remains soft and dry, back pain does not worsen, and distal pulses stay equal to baseline.
• Level of consciousness returns to the 0800 baseline.

Margin notethe trap is at 0820, not at 0800.

See → BOOK 08 · P4 for territory, → BOOK 08 · P9 for the traps, → BOOK 02 · P2 for step wording.

Takeawaythe wall predicted the bradycardia and the preload dependence, and both were foreseeable before the nitrate was given.