QuizMe 3

Pulmonary embolism (PE)

a 45-year-old woman underwent radical hysterectomy with bilateral pelvic node dissection. Day 2 post surgery she was noticed to be borderline hypoxia with with tachycardia. Physiotherapist noticed patient was short of breath on exercise.  An arterial blood gas study shows alveolar–arterial oxygen gradient, Sao2 of 89%. On examination, lungs were clear.  What do you think is the problem and the best next step in management?

  • Major pelvic surgery for cancer

  • Tachycardia & dyspnea with low sats.

  • Lungs clear on examination

Pulmonary Embolism (PE)

(A) D-dimer assay

(B) Lower limb doppler venous ultrasonography

(C) Ventilation–perfusion (V/Q) scan

(D) Computed tomography–pulmonary angiography  (CT-PA)

(E) Pulmonary angiography 

Computed tomography–pulmonary angiography  (CT-PA)

Pulmonary embolism (PE) is a common and often fatal medical condition that requires early diagnosis and ther- apy to reduce the risk of mortality. Despite the prevalence of PE, diagnosis remains challenging because the nonspecific  clinical presentation. Tachycardia, tachypnea, dyspnea, and hypoxemia are among a broad spectrum of clinical features described in patients with suspected PE, but non of these features is specific. A meta-analysis of 25,343 patients demonstrated relatively poor sensitiv- ity (85%) and specificity (51%) for clinical impression

CT–pulmonary angiography had been used as minimally invasive diagnostic test for PE since 1990s. The diagnostic accuracy of CTPA was evaluated in the PIOPED II study. In this study, 824 patients were evaluated, and the diagnostic accuracy of CTPA was compared with other reference investigations.The sensitivity and specificity of CTPA were 83% and 96%, respec- tively. For patients with a high, intermediate, or low clinical probability and a positive CT, the likelihood of PE was 96%, 92%, and 58%, respectively. 

  • Anderson DR, Kahn SR, Rodger MA, Kovacs MJ, Morris T, Hirsch A, et al. Computed tomographic pulmonary angiography vs ventilation–perfusion lung scanning in patients with suspected pulmonary embo- lism: a randomized controlled trial. JAMA 2007;298:2743–53.
  • Moores LK, Jackson WL Jr, Shorr AF, Jackson JL. Meta-analysis: outcomes in patients with suspected pulmonary embolism managed with computed tomographic pulmonary angiography. Ann Intern Med 2004;141:866 –74.
  • Stein PD, Fowler SE, Goodman LR, Gottschalk A, Hales CA, Hull RD, et al. Multidetector computed tomography for acute pulmonary embolism. PIOPED II Investigators. N Engl J Med 2006;354:2317–27
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