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OBJECTIVES/OBJECTIVE:Risk stratification for acute pulmonary embolism using imaging presence of right ventricular dysfunction is essential for triage; however, comprehensive transthoracic echocardiography has limited availability. We assessed the accuracy and timeliness of Pulmonary Critical Care Medicine Fellow's performance of goal-directed echocardiograms and intensivists' interpretations for evaluating right ventricular dysfunction in acute pulmonary embolism. DESIGN/METHODS:Prospective observational study and retrospective chart review. SETTING/METHODS:Four hundred fifty bed urban teaching hospital. PATIENTS/METHODS:Adult in/outpatients diagnosed with acute pulmonary embolism. INTERVENTIONS/METHODS:Pulmonary critical care fellows performed and documented their goal-directed echocardiogram as normal or abnormal for right ventricular size and function in patients with acute pulmonary embolism. Gold standard transthoracic echocardiography was performed on schedule unless the goal-directed echocardiogram showed critical findings. Attending intensivists blinded to the clinical scenario reviewed these exams at a later date. MEASUREMENTS AND MAIN RESULTS/RESULTS:Two hundred eighty-seven consecutive patients were evaluated for acute PE. Pulmonary Critical Care Medicine Fellows performed 154 goal-directed echocardiograms, 110 with complete cardiology-reviewed transthoracic echocardiography within 48 hours for comparison. Pulmonary Critical Care Medicine Fellow's area under the curve for size and function was 0.83 (95% CI, 0.75-0.90) and 0.83 (95% CI, 0.75-0.90), respectively. Intensivists' 1/2 area under the curve for size and function was (1) 0.87 (95% CI, 0.82-0.94), (1) 0.87 (95% CI, 0.80-0.93) and (2) 0.88 (95% CI, 0.82-0.95), (2) 0.88 (95% CI, 0.82-0.95). Median time difference between goal-directed echocardiogram and transthoracic echocardiography was 21 hours 18 minutes. CONCLUSIONS:This is the first study to evaluate pulmonary critical care fellows' and intensivists' use of goal-directed echocardiography in diagnosing right ventricular dysfunction in acute pulmonary embolism. Pulmonary Critical Care Medicine Fellows and intensivists made a timely and accurate assessment. Screening for right ventricular dysfunction using goal-directed echocardiography can and should be performed by pulmonary critical care physicians in patients with acute pulmonary embolism.

BACKGROUND: Computed tomography pulmonary angiography (CTA) is the gold standard for diagnosing pulmonary embolism (PE) but involves radiation and iodinated contrast exposure. Of orthopedic patients evaluated for PE, a minority have a positive CTA study. Herein, we evaluate end tidal carbon dioxide (ETCO2) as a method to identify patients at low risk for PE and may not require a CTA. We hypothesize that ETCO2 will be useful for predicting the absence of PE in postoperative orthopedic patients. METHODS: In this prospective study, all patients older than 18 years who were admitted for orthopedic surgery and who had a CTA performed for PE were eligible. These patients underwent an ETCO2 measurement. Patients were determined to have PE if they had a positive PE-protocol CT. RESULTS: Between May 2014 and April 2015, 121 patients met the inclusion criteria for the study. Of these patients, 84 had a negative CTA examination, 25 had a positive examination, and 12 had a nondiagnostic examination. We found a statistically significant difference (P = .03) when comparing the average ETCO2 values for the positive and negative CTA groups. An ETCO2 cutoff value of 43 mm Hg was 100% sensitive with a negative predictive value of 100% for absence of PE on CTA. CONCLUSION: This study demonstrates a significant difference in ETCO2 measurements between postoperative orthopedic patients with and without CTA-detected PE. A cutoff value of >43 mm Hg may be useful in excluding patients from undergoing CTA.

BACKGROUND: Duplex ultrasound is routinely used to evaluate suspected deep venous thrombosis after total joint arthroplasty. When there is a clinical suspicion for a pulmonary embolism, a chest angiogram (chest CTA) is concomitantly obtained. QUESTIONS/PURPOSES: Two questions were addressed: First, for the population of patients who receive duplex ultrasound after total joint arthroplasty, what is the rate of positive results? Second, for these patients, how many of these also undergo chest CTA for clinical suspicion of pulmonary embolus and how many of these tests are positive? Furthermore, what is the correlation between duplex ultrasound results and chest CTA results? METHODS: A retrospective chart review was conducted of total joint replacement patients in 2011 at a single institution. Inclusion criteria were adult patients who underwent a postoperative duplex ultrasonography for clinical suspicion of deep venous thrombosis (DVT). Demographic data, result of duplex scan, clinical indications for obtaining the duplex scan, and DVT prophylaxis used were recorded. Additionally, if a chest CTA was obtained for clinical suspicion for pulmonary embolus, results and clinical indication for obtaining the test were recorded. The rate of positive results for duplex ultrasonography and chest CTA was computed and correlated based on clinical indications. RESULTS: Two hundred ninety-five patients underwent duplex ultrasonography of which only 0.7% were positive for a DVT. One hundred three patients underwent a chest CTA for clinical suspicion of a pulmonary embolism (PE) of which 26 revealed a pulmonary embolus, none of which had a positive duplex ultrasound. CONCLUSION: Postoperative duplex scans have a low rate of positive results. A substantial number of patients with negative duplex results subsequently underwent chest CTA for clinical suspicion for which a pulmonary embolus was found, presumably resulting from a DVT despite negative duplex ultrasound result. A negative duplex ultrasonography should not rule out the presence of a DVT which can embolize to the lungs and thus should not preclude further workup when clinical suspicion exists for a pulmonary embolus.

Background Granulomatosis with polyangiitis (GPA) relapse can complicate the differential diagnosis of pulmonary lesions. Case Report A 70-year-old male smoker with GPA and emphysema presented with dyspnea, dry cough, and a right upper lobe pulmonary ground-glass opacity that persisted despite antibiotics. A trans-bronchial biopsy did not reveal active vasculitis, malignancy, or infection. He was treated for presumed GPA relapse based on pulmonary manifestations, renal failure, and elevated PR3-ANCA. Later, hematuria led to the cystoscopic discovery of a bladder wall lesion, which was diagnosed as micropapillary urothelial carcinoma not involving the muscularis propria. The patient developed an increasing pulmonary infiltrate with a new solid component, satellite lesions, and regional lymphadenopathy. A right upper lobe wedge resection showed metastatic urothelial carcinoma. Conclusions The simultaneous presentation of a pulmonary lesion and GPA relapse is a diagnostic challenge. The differential diagnosis should include the rare possibility of metastatic urothelial carcinoma, regardless of how the lesion appears radiographically.

Hemostasis is a major concern during the perioperative period. Changes in platelet aggregation and coagulation factors may contribute to the delicate balance between thrombosis and bleeding. We sought to better understand perioperative hemostasis by investigating the changes in platelet aggregation and coagulation factors during the perioperative period. We performed a prospective cohort analysis of 70 subjects undergoing non-emergent orthopedic surgery of the knee (n = 28), hip (n = 35), or spine (n = 7) between August 2011 and November 2011. Plasma was collected preoperatively (T1), 1-h intraoperatively (T2), 1-h (T3), 24-h (T4) and 48-h (T5) postoperatively. Platelet function testing was performed using whole blood impedance aggregometry. Coagulation assays were performed for factor VII, factor VIII, von Willebrand Factor (vWF), and fibrinogen. Of the 70 patients, mean age was 64.1 +/- 9.8 years, 61 % were female, and 74 % were Caucasian. Platelet activity decreased until 1 h postoperatively and then significantly increased above baseline at 24- and 48-h postoperatively. Compared to baseline, coagulation factors decreased intraoperatively. Factor VII activity continued to decrease, while FVIII, vWF, and fibrinogen all increased above baseline postoperatively. The results of our study indicate significant changes in platelet activity and coagulation factors during the perioperative period. Both platelet activity and markers of coagulation decrease during the intraoperative period and then some increase postoperatively. These changes may contribute to the hypercoagulabity and/or bleeding risk that occurs in the perioperative period. Future prospective studies aimed at correlating hemostatic changes with perioperative outcomes are warranted.