A 52-year-old hospitalized patient is evaluated for chest pain and persistent tachycardia. She was recently diagnosed with colon adenocarcinoma and underwent right hemicolectomy and ileocolic anastomosis 5 days ago. Yesterday, the patient was noted to be tachycardic and hypoxemic during physical therapy, and the tachycardia persisted at rest. She also has had shortness of breath and intermittent, right-sided chest pain. The patient is not using the incentive spirometer as frequently as advised. She is taking a liquid diet without significant abdominal pain or nausea but has had no bowel movements. Current medications are prophylactic-dose low molecular weight heparin and an opioid analgesic as needed. Temperature is 37.8 C (100 F), blood pressure is 116/72 mm Hg, pulse is 112/min, and respirations are 20/min. Oxygen saturation is 94% on 2 L/min oxygen by nasal cannula. On physical examination, the patient appears slightly uncomfortable and speaks in short sentences. Lung auscultation shows decreased breath sounds over the posterior right base. Cardiac examination reveals a regular rhythm without murmurs or gallops. The abdomen is soft with normal bowel sounds, and there is no erythema, drainage, or dehiscence of the surgical incision. There is mild, bilateral lower extremity pitting edema. ECG shows sinus tachycardia, and chest x-ray reveals right basal atelectasis. Which of the following is the best next step in the management of this patient?

Question

A 52-year-old hospitalized patient is evaluated for chest pain and persistent tachycardia.  She was recently diagnosed with colon adenocarcinoma and underwent right hemicolectomy and ileocolic anastomosis 5 days ago.  Yesterday, the patient was noted to be tachycardic and hypoxemic during physical therapy, and the tachycardia persisted at rest.  She also has had shortness of breath and intermittent, right-sided chest pain.  The patient is not using the incentive spirometer as frequently as advised.  She is taking a liquid diet without significant abdominal pain or nausea but has had no bowel movements.  Current medications are prophylactic-dose low molecular weight heparin and an opioid analgesic as needed.  Temperature is 37.8 C (100 F), blood pressure is 116/72 mm Hg, pulse is 112/min, and respirations are 20/min.  Oxygen saturation is 94% on 2 L/min oxygen by nasal cannula.  On physical examination, the patient appears slightly uncomfortable and speaks in short sentences.  Lung auscultation shows decreased breath sounds over the posterior right base.  Cardiac examination reveals a regular rhythm without murmurs or gallops.  The abdomen is soft with normal bowel sounds, and there is no erythema, drainage, or dehiscence of the surgical incision.  There is mild, bilateral lower extremity pitting edema.  ECG shows sinus tachycardia, and chest x-ray reveals right basal atelectasis.  Which of the following is the best next step in the management of this patient?

Quizplus · Accepted Answer

11ec25c8_d951_db66_bc81_0f45fcffa052_MD0003_00 This patient has several risk factors for venous thromboembolic disease and multiple signs and symptoms (eg, tachycardia, dyspnea, tachypnea, hypoxemia) that suggest acute pulmonary embolism (PE). Both surgery and cancer are independent risk factors for PE, and large intraabdominal surgeries for cancer resection (eg, hemicolectomy) have an even greater combined risk. Although prophylactic-dose anticoagulation may reduce the risk of PE, it does not eliminate the risk completely, especially in high-risk patient populations. This patient's Wells score is best calculated as 7 (1.5 points for tachycardia, 1.5 points for recent surgery, 1 point for cancer, and 3 points for PE being more likely than other diagnoses), indicating likely pretest probability of PE. In such patients, CT pulmonary angiography is the initial diagnostic test of choice due to high diagnostic accuracy. Ventilation-perfusion scan is an alternative option in patients unable to receive intravenous contrast (eg, due to renal dysfunction or allergy). Wells score Therapeutic-dose (as opposed to prophylactic dose) low molecular weight heparin (eg, enoxaparin, dalteparin) is often the preferred treatment for acute PE in cancer patients due to a possible increased risk of malignancy-related bleeding with direct oral anticoagulants (eg, rivaroxaban). (Choice A) Initiation of broad-spectrum antibiotics is appropriate for suspected sepsis (eg, due to pneumonia); however, this patient has no localizing evidence of infection (eg, cough) and a chest x-ray with no evidence of an infiltrate. Tachycardia, tachypnea, and low-grade fever are explained by acute PE. (Choice B) D-dimer testing can be useful in ruling out PE in patients with unlikely pretest probability. However, the test has no value in patients with likely pretest probability of PE (eg, Wells score >4) due to an unacceptably high rate of false-negative results in such patients. (Choice C) Increasing this patient's analgesic dose is not appropriate as her right-sided chest pain is likely related to PE, requiring prompt diagnosis and treatment. (Choice D) Postoperative atelectasis is common, often resulting from shallow breathing in the setting of anesthesia and postoperative pain. Positive-pressure ventilation is sometimes used to help open collapsed alveoli and improve atelectasis; however, it would not address this patient's likely probability of PE. In addition, atelectasis does not typically cause chest pain. Educational objective: Prophylactic anticoagulation does not eliminate the risk of acute pulmonary embolism (PE), especially in high-risk patient populations (eg, postoperative cancer resection). CT pulmonary angiography is the initial diagnostic test of choice in patients with likely pretest probability of acute PE. References: Duration of prophylaxis against venous thromboembolism with enoxaparin after surgery for cancer. (http://www.ncbi.nlm.nih.gov/pubmed/11919306)

A 52-Year-Old Hospitalized Patient Is Evaluated for Chest Pain and Persistent