Pulmonary Embolism and Pneumothorax Flashcards
What condition is known as “the great Masquerader”?
Pulmonary Embolism
Pulmonary Embolism:
Obstruction of the pulmonary artery or its branches by material (thrombus, tumor, air or fat) that originated elsewhere in the body
Form of venous thromboembolism (VTE)
Common and fatal
Clinical presentation is variable and often nonspecific making the diagnosis challenging
PE Epi:
Higher in males
Incidence rises with increasing age particularly women
100,000 annual deaths in the US
Age-adjusted mortality rates for African-American adults is 50 % higher than whites
PE risk factors:
Obesity
Pregnancy
Prior history of PE
Increasing age
Inherited (factor V Leiden, prothrombin gene mutation, protein C and S, antithrombin deficiency)
Acquired (malignancy, surgery, trauma, pregnancy, oral contraceptives, HRT, immobilization,) extended travel
PE symptoms:
Dyspnea at rest or with exertion (73%) * Pleuritic chest pain (44%)* Cough (37%)* Orthopnea Calf or thigh pain and or swelling (44%) Wheezing Hemoptysis *many patients with large PE have mild or nonspecific symptoms or asymptomatic *most common presenting symptoms*
PE signs:
Tachypnea (70%) Calf or thigh swelling/edema, erythema, tenderness, palpable cords (47%) Tachycardia (30%) Rales Decreased breath sounds An accentuated pulmonic component of the 2nd heart sound Jugular venous distension Fever, mimicking pneumonia
DDx PE:
Pneumonia, asthma, chronic obstructive pulmonary disease
Congestive heart failure
Pericarditis
Pleurisy “Viral syndrome”, costochondritis, musculoskeletal discomfort
Rib fracture pneumothorax
Acute coronary syndrome
Anxiety
Laboratory Tests PE:
CBC and chemistry (nonspecific, but routinely done)
Leukocytosis, ↑ESR, ↑LDH, ↑AST
ABG (neither sensitive or specific)
PT/PTT/INR
BNP
May be useful for prognostic risk stratification of patients diagnosed with PE
Troponin
Elevated in 30-50% of patients who have a moderate to large PE; assess prognosis
D-dimer
Sensitive, but poorly specific most useful when used in conjunction with clinical suspicion to facilitate a decision to proceed with further testing
For patients whom PE is unlikely and level is < 500 ng/mL, no further testing required
For patients in whom PE is likely and is > 500 ng/mL, diagnostic imaging should be performed
* ↑ myocardial infarction, pneumonia, sepsis, cancer, postoperative state, 2nd
and 3rd trimester of pregnancy
CXR PE:
Chest radiograph
Assess for other causes of symptoms
Ventilation perfusion scan VQ, not necessary if CT is planed
Hamptons’ hump and Westermarks’ sign are rare
*should raise the suspicion for PE
S1Q3T3
PE EKG
Diagnostic algorithms
- Wells
- PERC rule-out criteria
Wells:
Risk stratifies patients for PE
Used in conjunction with D-dimer test
Clinical suspicion for PE in the patient
3 tiers (low, moderate, High) or 2 tiers (unlikely, likely)
Wells is not meant to diagnose PE but to guide workup by predicting pre-test probability of PE and appropriate testing to rule out the diagnosis
PERC rule-out Criteria:
Alternative to sensitive D-dimer testing with a low-probability assessment for PE
*best used in patients who present to the ED with dyspnea or chest pain in whom the gestalt estimate for PE is < 15 %; 8 Criteria’s
1st choice diagnostic modality for PE (with contrast is gold standard) :
CTA
if patient is renal impaired what test do you do?
VQ scan
