Article updated July 24, 2017
EMS providers encounter a wide variety of patient presentations. Determining the sick patients from the not sick persons can sometimes be difficult. A systematic approach to patient assessment during each patient encounter will help the professional EMS provider avoid overlooking subtle clues. Some cases may appear to be obvious from the start, but may require the EMS provider to change strategies part-way through the encounter. This EKG patient case illustrates the benefit of applying a systematic method to patient assessments and ultimately affects the patient’s outcome.
The EKG Club experts created this case for these learning objectives:
- Basic: To understand the importance of the proper use of a 12-lead EKG in the differential diagnosis of a medical patient.
- Intermediate: Recognition of ST Elevation Myocardial Infarction (STEMI) on the 12-lead EKG. The importance of a systematic patient assessment (eg. SAMPLE History). Identifying coronary anatomy in 12-lead EKG interpretation.
- Advanced: Awareness of the role of anti-platelet medications in the post-stent patient. Awareness of the frequency of restonosis following stenting with bare metal and drug eluding cardiac stents.
Patient Presentation: Man with weakness
One hot and humid day in a small suburban city the radio silence is finally broken at 1100 hours with the following dispatch: “Medic 1 , Engine 1 respond to the intersection of Main Street and Jones Street for a man down.”
The location is not far from where you had been waiting and you arrive on scene in four minutes. On the scene is an elderly male sitting on the front porch of a house not far from the road.
A Good Samaritan neighbor says that he helped Mr. Smith to the porch after finding him walking and talking inappropriately on the side of the roadway before he sat down on the sidewalk complaining of weakness. You recall the temperature has already reached 90 degrees F and the humidity is 90 percent.
Patient Assessment Findings
Beginning the assessment, your general impression reveals an elderly male who appears lethargic. He does make eye contact and appears to have a patent airway and responds to questions coherently, although mildly confused. His clothes appear to be rather dirty, causing you to wonder if he may be homeless. The patient appears very diaphoretic and his skin color is pale.
Primary assessment:
Airway: Open, intact
Breathing: Slightly labored
Circulation: Radial pulse present, skin is very diaphoretic, pale, cool to the touch
Disability: Patient is alert but responds with somewhat confused time and place
Exposure: No signs of trauma or any external findings
You begin to formulate a list of differential diagnosis conditions, with heat exhaustion at the top of the list. The patient denies any trauma or exertion prior to the episode of weakness.
You ask your partner to assist you in moving Mr. Smith to the ambulance, still running with the air conditioning on high, to provide some relief and to perform a more detailed assessment. Your partner gathers and reports the following initial vital signs:
Patient’s vital signs:
Heart Rate: 70 bpm
Blood Pressure: 142/86 mm Hg
Respirations: 20 rom
SpO2: 96 percent on room air
Pain: Patient slightly lethargic, unable to answer
Past Medical History:
The Good Samaritan lives next door to Mr. Smith and has told you that he had some type of heart procedure last week and he needs to return for more tests. The helpful neighbor is unable to identify what procedure was performed or what tests are needed.
Allergies:
No known drug allergies
Medications:
You find a shopping bag nearby with several medication bottles inside; clopidogrel, metoprolol, lisinopril, folic acid, vitamin B12, vitamin B6 and aspirin.
Initial patient treatment
You acquire a 3-lead EKG with some difficulty due to the electrodes coming off the patient’s diaphoretic skin. Your partner acquires the 12-lead EKG and you initiate an IV of 0.9 percent normal saline in the patient’s left arm with an 18-gauge catheter. A blood glucose check reveals a glucose level of 126 mg/dl (7 mmol/L).
The patient begins to complain of some discomfort in his chest and rates it a 6/10 on the pain scale. You decide to administer four baby aspirin (328mg) per written standing orders. Your partner hands you the 12-lead.
Initial EKG (click for larger image)
The computed interpretation is: Unavailable due to artifact. These are the intrepretation findings based on the EKG Club recommended interpretation checklist.
- Rate & Rhythm: Rate 78 and regular
- P-wave: Present in lead II, unable to determine in other leads due to artifact
- PR interval: 0.12 sec in lead II
- QRS interval: Appears to be < 0.12, difficult to determine due to artifact
- QRS complex & mean axis: QRS width not significant, left axis deviation
- ST segment: ST segment depression in leads II, III, aVF / ST segment elevation in leads V1-V5, I, aVL
- T wave: Tall in V2-V5
- U wave: Not visible
- QT interval: 0.400s QT/0.456s QTc
Consider these questions about the initial 12-lead EKG:
- What would you do about the artifact?
- Can you determine anything through the artifact?
- What do you notice about this EKG?
- Where should you transport this patient?
Patient response to treatment:
En route to the hospital where the patient’s recent “unknown” procedure was performed, you administer 0.4mg of nitroglycerin spray sublingually. You setup an infusion pump in preparation for administering intravenous nitroglycerin after the patient reports his pain has nearly resolved and he is markedly less diaphoretic.
Your partner hands you another 12-lead EKG and you ask for another set of vitals. He reports back this second set of vital signs:
Heart Rate: 76 bpm
Blood Pressure: 134/72 mm Hg
Respirations: 18 rpm
SpO2: 98 percent
Pain: Patient is still slightly lethargic, but responds more clearly now
Second EKG (click for larger image):
The computer’s interpretation is:
Abnormal EKG **unconfirmed**
HR: 72
PRI: 0.000
QRSd: 0.142s
QT/QTc: 0.392s/0.429s
Paxis: 0
QRSaxis: 10
Taxis: 17
It reads:
- Undetermined rhythm
- Nonspecific intraventricular block
- Cannot rule out anteroseptal infarct, age undetermined
Following a routine EKG intrepretation processes leads to these 12-lead EKG findings:
- Rate & Rhythm: 72 complexes similar to first EKG, sinus rhythm
- P-wave: Unable to determine due to artifact
- PR interval: Unable to determine due to artifact
- QRS interval: 0.142s
- QRS complex & mean axis: QRS wide, left axis deviation
- ST segment: Slight ST segment depression in lead II / significant ST segment depression in leads V1-V5
- T wave: Tall in V2-V5
- U wave: Not visible
- QT interval: 0.392s QT /0.429s QTc
Consider these additional questions about the 12-lead EKG:
- What changes do you notice between the first and second EKG?
- What are possible reasons for these changes?
- What do those changes mean for your treatment plan?
- What clues are available to give you a high index of suspicion regarding the unknown procedure and other risks?
Patient follow-up: How to use patient history, 12-lead EKG to diagnose STEMI
