Diagnostic pathways in acute pulmonary embolism: recommendations of the PIOPED II Investigators.
Explore the source record for details and available documents.
Acute Disease↗
Biomedical subjects
Kenneth V Leeper
Publications and source records attributed to Kenneth V Leeper.
Multidetector computed tomography for acute pulmonary embolism.
BACKGROUND: The accuracy of multidetector computed tomographic angiography (CTA) for the diagnosis of acute pulmonary embolism has not been determined conclusively. METHODS: The Prospective Investigation of Pulmonary Embolism Diagnosis II trial was a prospective, multicenter investigation of the accuracy of multidetector CTA alone and combined with venous-phase imaging (CTA-CTV) for the diagnosis of acute pulmonary embolism. We used a composite reference test to confirm or rule out the diagnosis of pulmonary embolism. RESULTS: Among 824 patients with a reference diagnosis and a completed CT study, CTA was inconclusive in 51 because of poor image quality. Excluding such inconclusive studies, the sensitivity of CTA was 83 percent and the specificity was 96 percent. Positive predictive values were 96 percent with a concordantly high or low probability on clinical assessment, 92 percent with an intermediate probability on clinical assessment, and nondiagnostic if clinical probability was discordant. CTA-CTV was inconclusive in 87 of 824 patients because the image quality of either CTA or CTV was poor. The sensitivity of CTA-CTV for pulmonary embolism was 90 percent, and specificity was 95 percent. CTA-CTV was also nondiagnostic with a discordant clinical probability. CONCLUSIONS: In patients with suspected pulmonary embolism, multidetector CTA-CTV has a higher diagnostic sensitivity than does CTA alone, with similar specificity. The predictive value of either CTA or CTA-CTV is high with a concordant clinical assessment, but additional testing is necessary when the clinical probability is inconsistent with the imaging results.
Acute Disease↗
Diagnostic pathways in acute pulmonary embolism: recommendations of the PIOPED II investigators.
PURPOSE: To formulate comprehensive recommendations for the diagnostic approach to patients with suspected pulmonary embolism, based on randomized trials. METHODS: Diagnostic management recommendations were formulated based on results of the Prospective Investigation of Pulmonary Embolism Diagnosis II (PIOPED II) and outcome studies. RESULTS: The PIOPED II investigators recommend stratification of all patients with suspected pulmonary embolism according to an objective clinical probability assessment. D-dimer should be measured by the quantitative rapid enzyme-linked immunosorbent assay (ELISA), and the combination of a negative D-dimer with a low or moderate clinical probability can safely exclude pulmonary embolism in many patients. If pulmonary embolism is not excluded, contrast-enhanced computed tomographic pulmonary angiography (CT angiography) in combination with venous phase imaging (CT venography), is recommended by most PIOPED II investigators, although CT angiography plus clinical assessment is an option. In pregnant women, ventilation/perfusion scans are recommended by many as the first imaging test following D-dimer and perhaps venous ultrasound. In patients with discordant findings of clinical assessment and CT angiograms or CT angiogram/CT venogram, further evaluation may be necessary. CONCLUSION: The sequence for diagnostic test in patients with suspected pulmonary embolism depends on the clinical circumstances.
Acute Disease↗
Clinical characteristics and treatment patterns among patients with ventilator-associated pneumonia.
STUDY OBJECTIVES: To evaluate clinical characteristics and treatment patterns among patients with ventilator-associated pneumonia (VAP), including the implementation of and outcomes associated with deescalation therapy. DESIGN: Prospective, observational, cohort study. SETTING: Twenty ICUs throughout the United States. PATIENTS: A total of 398 ICU patients meeting predefined criteria for suspected VAP. INTERVENTIONS: Prospective, handheld, computer-based data collection regarding routine VAP management according to local institutional practices, including clinical and microbiological characteristics, treatment patterns, and outcomes. MEASUREMENTS AND RESULTS: The most frequent ICU admission diagnoses in patients with VAP were postoperative care (15.6%), neurologic conditions (13.3%), sepsis (13.1%), and cardiac complications (10.8%). The mean (+/- SD) duration of mechanical ventilation prior to VAP diagnosis was 7.3 +/- 6.9 days. Major pathogens were identified in 197 patients (49.5%) through either tracheal aspirate or BAL fluid and included primarily methicillin-resistant Staphylococcus aureus (14.8%), Pseudomonas aeruginosa (14.3%), and other Staphylococcus species (8.8%). More than 100 different antibiotic regimens were prescribed as initial VAP treatment, the majority of which included cefepime (30.4%) or a ureidopenicillin/monobactam combination (27.9%). The mean duration of therapy was 11.8 +/- 5.9 days. In the majority of cases (61.6%), therapy was neither escalated nor deescalated. Escalation of therapy occurred in 15.3% of cases, and deescalation occurred in 22.1%. The overall mortality rate was 25.1%, with a mean time to death of 16.2 days (range, 0 to 49 days). The mortality rate was significantly lower among patients in whom therapy was deescalated (17.0%), compared with those experiencing therapy escalation (42.6%) and those in whom therapy was neither escalated nor deescalated (23.7%; chi2= 13.25; p = 0.001). CONCLUSIONS: Treatment patterns for VAP vary widely from institution to institution, and the overall mortality rate remains unacceptably high. The deescalation of therapy in VAP patients appears to be associated with a reduction in mortality, which is an association that warrants further clinical study.
Adolescent↗
Nonresolving pneumonia.
Uncertainty over the expected clinical course of a community-acquired or nosocomial pneumonia is a common reason for pulmonary consultation. Determining which patients with prolonged pneumonia and at what point during therapy they should undergo further evaluation can be challenging. This article reviews "normal" resolution times for the most common pneumonias, risk factors for delayed resolution, and infectious and noninfectious conditions that can cause nonresolving pneumonia. An approach to the evaluation of the patient with this common problem is described.
Anti-Bacterial Agents↗
DVT and pulmonary embolism: Part I. Diagnosis.
The incidence of venous thromboembolic diseases is increasing as the U.S. population ages. At least one established risk factor is present in approximately 75 percent of patients who develop these diseases. Hospitalized patients and nursing home residents account for one half of all cases of deep venous thrombosis. A well-validated clinical prediction rule can be used for risk stratification of patients with suspected deep venous thrombosis. Used in combination with D-dimer or Doppler ultrasound tests, the prediction rule can reduce the need for contrast venography, as well as the likelihood of false-positive or false-negative test results. The inclusion of helical computed tomographic venography (i.e., a below-the-pelvis component) in pulmonary embolism protocols remains under evaluation. Specific combinations of a clinical prediction rule, ventilation-perfusion scanning, and D-dimer testing can rule out pulmonary embolism without an invasive or expensive investigation. A clinical prediction rule for pulmonary embolism is most helpful when it is used with subsequent evaluations such as ventilation-perfusion scanning, D-dimer testing, or computed tomography. Technologic advances are improving the resolution of helical computed tomography to allow detection of smaller emboli; however, further study is needed to provide definitive evidence supporting the role of this imaging technique in the diagnosis of pulmonary embolism. D-dimer testing is helpful clinically only when the result is negative. A negative D-dimer test can be used in combination with a clinical decision rule, ventilation-perfusion scanning, and/or helical computed tomography to lower the probability of pulmonary embolism to the point that aggressive treatment is not required. Evidence-based algorithms help guide the diagnosis of deep venous thrombosis and pulmonary embolism.
Diagnosis, Differential↗
DVT and pulmonary embolism: Part II. Treatment and prevention.
Treatment goals for deep venous thrombosis include stopping clot propagation and preventing the recurrence of thrombus, the occurrence of pulmonary embolism, and the development of pulmonary hypertension, which can be a complication of multiple recurrent pulmonary emboli. About 30 percent of patients with deep venous thrombosis or pulmonary embolism have a thrombophilia. An extensive evaluation is suggested in patients younger than 50 years with an idiopathic episode of deep venous thrombosis, patients with recurrent thrombosis, and patients with a family history of thromboembolism. Infusion of unfractionated heparin followed by oral administration of warfarin remains the mainstay of treatment for deep venous thrombosis. Subcutaneously administered low-molecular-weight (LMW) heparin is at least as effective as unfractionated heparin given in a continuous infusion. LMW heparin is the agent of choice for treating deep venous thrombosis in pregnant women and patients with cancer. Based on validated protocols, warfarin can be started at a dosage of 5 or 10 mg per day. The intensity and duration of warfarin therapy depends on the individual patient, but treatment of at least three months usually is required. Some patients with thrombophilias require lifetime anticoagulation. Treatment for pulmonary embolism is similar to that for deep venous thrombosis. Because of the risk of hypoxemia and hemodynamic instability, in-hospital management is advised. Unfractionated heparin commonly is used, although LMW heparin is safe and effective. Thrombolysis is used in patients with massive pulmonary embolism. Subcutaneous heparin, LMW heparin, and warfarin have been approved for use in surgical prophylaxis. Elastic compression stockings are useful in patients at lowest risk for thromboembolism. Intermittent pneumatic leg compression is a useful adjunct to anticoagulation and an alternative when anticoagulation is contraindicated.
Anticoagulants↗
Pulmonary embolism mortality in the United States, 1979-1998: an analysis using multiple-cause mortality data.
BACKGROUND: Pulmonary thromboembolism (PTE) is a common clinical problem that is associated with substantial morbidity and mortality. Estimates of PTE mortality and predictions of PTE trends have varied widely. These estimates play a role in the planning of national health strategies. The analysis of pulmonary embolism mortality trends and comorbidities may elucidate how well we treat and prevent the disease as well as identify additional risk factors. METHODS: We analyzed PTE (International Classification of Diseases, Ninth Revision code 415.1) as reported on death certificates in the Multiple-Cause Mortality Files compiled by the National Center for Health Statistics from 1979 to 1998. RESULTS: Of all the 42932973 decedents, 572773 (1.3%) had PTE listed on their death certificates and 194389 of these (33.9%) had PTE as the underlying cause of death. The age-adjusted rate of deaths with PTE decreased from 191 per million in 1979 to 94 per million in 1998 overall, decreasing 56% for men and 46% for women. During the study period, the age-adjusted mortality rates for blacks were consistently 50% higher than those for whites, and those for whites were 50% higher than those for people of other races (Asian, American Indian, etc). Within racial strata, mortality rates were consistently 20% to 30% higher among men than among women. Conditions that were of higher likelihood in persons who died with PTE included thrombophlebitis, fractures, trauma, postoperative complications, certain cancers, and the inflammatory bowel diseases. CONCLUSIONS: Mortality with PTE in the United States has decreased during the 20-year period. The mortality rates between men and women and between racial groups vary substantially. These findings may be useful in better directing preventive therapy efforts.
Adolescent↗
Troponin levels as a guide to treatment of pulmonary embolism.
Right ventricular dysfunction in hemodynamically stable patients with acute pulmonary embolism may be a harbinger of adverse outcomes and may potentially result in the early use of thrombolytic therapy. Risk stratification of these patients is an area of recent and intense investigation with a focus on the assessment of right ventricular function after the embolic event. Echocardiography has been used to identify right ventricular dysfunction but is potentially hampered by a number of limitations. With the onset of right ventricular dilation and possible ischemia in acute pulmonary embolism, elevated serum troponins may be an early and reliable marker of right ventricular dysfunction. In acute pulmonary embolism, both right ventricular dysfunction by echocardiogram and elevated troponin levels have been shown to predict an adverse outcome. Therefore, serum troponin levels should help stratify patients with submassive acute pulmonary embolism into a group in which aggressive medical or surgical intervention would be considered.
Acute Disease↗
Epidemiology and microbiology of hospital-acquired pneumonia.
Hospital-acquired pneumonia (HAP) is the second most common nosocomial infection in the critically ill patient and is associated with the greatest mortality and increased morbidity and cost of care. The major risk factor for the development of HAP in intensive care is the occurrence of intubation and mechanical ventilation, giving rise to the term ventilator-associated pneumonia (VAP). Incidence of VAP varies in different populations of critically ill patients and generally ranges from 9 to 20%, with an overall rate of 10 to 15 cases per 1,000 ventilator days. The cumulative risk of developing VAP is ~1% per day of mechanical ventilation (MV). The crude mortality rate of VAP is 60% and the estimates of attributable risk range from 27 to 43%. Mortality from VAP is influenced by host factors, the virulence of the pathogens, and the adequacy of initial antimicrobial therapy. The etiologic agents for VAP differ according to the population studied, duration of hospital stay, time after intubation, and prior antimicrobial therapy. Risk factors include nonmodifiable factors like age, chronic obstructive pulmonary disease, severe head trauma, and multiple trauma, and modifiable factors like large volume gastric aspiration, duration of MV, elevated gastric pH, histamine type 2 blocker therapy, ventilator circuit change frequency, self-extubation, and reintubation. The impact that diagnosis using invasive diagnostic techniques may have on the epidemiological characteristics of VAP are unknown, but may potentially reduce problems resulting from misclassification of this entity.
Journal Article↗