Case Presentation by Dr. Stephanie Wise
A 42-year-old man presents to the Emergency Department with a 2-day history of coughing up blood. His symptoms started about 5 days after he returned from a week-long business trip in South Africa. He has not had any fevers or weight loss. He does have chest pain, however, on the left antero-lateral side. He describes this pain as sharp, worse with a deep breath. He denies any shortness of breath. No nausea or vomiting or diarrhea. Appetite has been normal.
Medications: albuterol HFA PRN
Surgeries: Appendectomy, age 19
FH: HTN, “blood problem” in two uncles
SH: Smokes 1/2 pack daily for 12 years; occasional alcohol, denies ilicit drugs
BP 134/85, HR 108, RR 21, Temp 37.1
General: Well-developed overweight male, sitting up on stretcher, mild distress
HEENT: PERRL, EOMI; trachea midline, no LAD
CV: Regular rhythm, tachycardic, no murmurs
Resp: Breath sounds decreased at the left base with mild crackles; otherwise clear to auscultation, no wheezing
ABD: soft, non-tender, non-distended; normal active bowel sounds
Extremities: pulses equal, no deformities seen
Neuro: AOx3, normal strength and sensation in all extremities; no facial droop or other focal deficits; gait normal; reflexes 2+ in all extremities
143 105 12
4.1 21 0.9 Glucose 88
EKG shows sinus tachycardia, rate of 112, no ST elevations or depressions
1. What is the most common inherited hypercoagulable state?
a. Factor V Leiden
b. Protein C deficiency
c. Anti-thrombin III deficiency
d. von Willebrand disease
e. Sticky platelet syndrome
2. In the presence of acute pulmonary embolism, what is true of ECG findings:
a. “S1Q3T3” is the most sensitive finding
b. Anterior T wave inversions are the most specific finding
c. Typically no abnormality is seen on ECG
d. Sinus tachycardia is an uncommon finding
3. Which statement is correct about the diagnosis of pulmonary embolism?
a. Lower extremity Doppler studies that are positive for DVT are present in 70% of PE patients
b. The chest x-ray is typically normal
c. Pulmonary angiography is the gold standard
d. A D-dimer’s value is in its positive predictive value
4. What percentage of ambulatory patients who present with PE have no identifiable clinical risk factors?
1) A. The most common inherited hypercoagulable state is Factor V Leiden. This is characterized by the production of a “rogue clotter” protein, which is also resistant to proteolysis by protein C. It is inherited in an autosomal recessive fashion, and is most common in people of northern European descent. Von Willebrand disease is the most common genetic cause of excessive bleeding. The other options are other inherited hypercoagulable disorders.
2) B. Of the options provided, the correct statement is that T wave inversions are the most specific finding (81%) in the presence of pulmonary embolism. This has been the most common finding in some studies (68%).
S1Q3T3 is an indicator of cor pulmonale, which makes it less specific of a finding, and it is also not considered sensitive as it is only present in approximately 50% of cases.
Typically an ECG of a PE patient is abnormal; the difficulty is that the abnormalities are non-specific. The value of the ECG is more in ruling out other causes of the patient’s symptoms, especially myocardial infarction.
Sinus tachycardia is a common finding, but again, very non-specific.
3) C. Pulmonary angiography is the gold standard for diagnosis of pulmonary embolism. Doppler imaging can indicate a source of PE, but up to 60% of ambulatory patients (the people we’ll be seeing in the ED) do not have DVT.
In the presence of pulmonary embolism, the chest x-ray typically has some abnormality, but the abnormalities are usually both non-sensitive and non-specific. The findings more specific to PE (Hampton’s hump, Westermark sign and Fleischner’s lines) are rare. If you see them, however, you should be able to recognize them. Also, if you suspect PE, you should at least be aware of these findings so that you can identify them when present.
The value of D-dimer in diagnosis of PE is to rule it out. If clinical suspicion is low and the D-dimer is normal, PE is rare (2% or less). Thus, the value is in its negative predictive value.
4) C. Half of patients who present to the ED with a pulmonary embolism will have no identifiable clinical risk factors. Work-up will ultimately try to identify previously unidentied risk factors, but for the ED physician, a high index of suspicion needs to be present even if there is not a “convenient” history like what our patient in this case provided. Otherwise cases will be missed, which could be detrimental to our patients.
Filed under: Intern Report |