Note: the following material is for personal use only see below for

Pulmonary Embolism

• 
  EKG: sinus tachycardia, new-onset Afib/flutter, non-specific ST changes are most common finding / classical finding (S1Q3T3): I deep S, III Q wave, inverted T III / V_1-4 inverted T waves (only 15%) [pic]
  
• 
  CXR: r/o pneumothorax et al / Westermark’s oligemia (15%) [pic] / raised hemi-diaphragm / pleural-based parenchymal radiodensity with rounded profile toward hilus (Hampton’s lump or hump) / pleural effusion (transudate or exudates) / Palla sign (enlargement of right descending pulmonary artery)
  
• 
  ABG on RA (expect respiratory alkalosis, PaO2 < 80 / PaCO2 < 30)
  
• 
  VQ scan: [pic] [pic2] [normal: stop / high: treat / low-intermediate (up to 40% have PE) / most PE have moderate to low probability VQ scans / often want to go directly to CT for 2 reasons 1) pre-existing lung disease usually causes non-informative study 2) CT is much faster to get (especially during off-hours) / T-99 [pic] / 60% of COPD patients have indeterminate scans
  
• 
  CT angiogram [pic]: better for central pulmonary arteries, not peripheral / not so good for diagnosing sub-segmental PE / Note: if not PE, CT reveals the alternate diagnosis > 30% of cases / some choose pulmonary angiogram 1^st if patient’s renal function only allows one test / false negatives (patient hemodynamics, motion artifact, oblique running arteries, note: interlobar artery in r. lung not well seen) / false positives (hilar, bronchopulmonary lymph nodes, artifacts, reduced pulmonary perfusion) / Note: differing opinions (obstruction, PE, etc.) is the rule if reviewed by > 1 radiologist, you’ll see
  
• 
  Pulmonary angiogram [pic]: gold standard / 1% morbidity/mortality of test / rarely done unless equivocal or negative VQ/CT and high suspicion for PE
  
• 
  Ultrasound: looking for DVT in lower extremities (most come from pelvis however) / more than ½ will have leg vein clot (sensitivity is high if study done properly), which means ⅓ will have no DVT
  
• 
  Echocardiogram: may see RV dilation/strain/failure (which is leading cause of death from PE, and which may provide support for use of thrombolytics) / depressed RV function with apical sparing is McConnell’s sign (does not always mean PE) / this is an adjuvant test used to determine RV function (and may also provide alternative explanations for patient’s symptoms) but is NOT a diagnostic test for PE
  
• 
  D-dimers: if lab does proper assay, can have 90% sensitivity with lower specificity (cannot rule in, but does have high negative predictive value)
  

• 
  Anticoagulation (heparin or LMWH then coumadin as soon as PTT is therapeutic, same day with LMWH) / 5% overall recurrence rate / 2% overall risk of major bleed / Duration: 6 months if risk-factor associated, indefinite if no identifiable risk-factors. [annals] / recent studies suggest once-daily LMWH may be as good as twice-daily (2009) and measure factor-Xa levels (best way to ensure therapeutic and safe range (esp. with renal insufficiency)
  
• 
  Thrombolysis – controversial when to use. [NEJM] says use alteplase + heparin when concern for RV failure is high. [NEJM] / accepted risk of ICH about 3%
  

• 
  Thrombectomy – for pts who have RHF and cannot tolerate or fail thrombolysis
  
• 
  IVC filters (vena cava interruption) with known DVT’s, poor cardiopulmonary reserve, PE in spite of anti-coagulation or contraindications to anti-coagulation (recent CVA or CNS surgery, CNS malignancy, GI bleed) / many complications of filters (overall 10-20%) [pic]
  

involvement of posterior compartment of the lateral pharyngeal space, bacteremia, septic IJ thrombophlebitis

Diagnosis: CT/MRI/ultrasound, high degree of clinical suspicion

• 
  prolonged IV antibiotics against anaerobes / 1^st metronidazole, 2^nd clindamycin, chloramphenicol (often produce B-lactamases)
  
• 
  surgical ligation or IJ excision may be necessary
  
• 
  some feel heparin is useful