Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “EMBOLISM”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,081 records · Page 60Linked to original sources

Prevalence of fat embolism following bilateral simultaneous and unilateral total hip arthroplasty performed with or without cement : a prospective, randomized clinical study.

BACKGROUND: Controversy exists regarding the safety of bilateral simultaneous total hip arthroplasty, in part because of the potentially higher prevalence of pulmonary fat embolism. The purpose of the present study was to determine if unilateral and bilateral simultaneous total hip arthroplasty procedures resulted in different prevalences of fat embolization, different degrees of hemodynamic compromise, or different levels of hypoxemia or mental status changes. METHODS: One hundred and fifty-six consecutive patients undergoing primary total hip arthroplasty were prospectively enrolled in the study. The study group included fifty patients undergoing bilateral simultaneous total hip arthroplasty and 106 patients undergoing unilateral total hip arthroplasty. One hundred hips were treated with a cemented stem, and 106 were treated with a cementless stem. Arterial and right atrial blood samples were obtained before implantation (baseline); at one, three, five, and ten minutes after implantation of the acetabular and femoral components; and at twenty-four and forty-eight hours after the operation. Arterial blood pressure, right atrial pressure, arterial oxygen tension, and carbon-dioxide tension were also monitored at these times. The presence of lipid and cellular contents of bone marrow was determined. RESULTS: The prevalence of fat embolism was not significantly different between the groups managed with bilateral and unilateral total hip arthroplasty or between the groups managed with cemented and cementless stems. Similarly, the prevalence of bone-marrow-cell embolization was not significantly different between the groups managed with bilateral and unilateral total hip arthroplasty or between the groups managed with cemented and cementless stems. Patients with bone-marrow-cell embolization had a significantly lower arterial oxygen tension (p = 0.022) and oxygen saturation (p = 0.017) than did patients without bone-marrow-cell embolization on the first postoperative day. Four patients with bone-marrow cells in the blood samples that were obtained from the right atrium on the first postoperative day had development of diffuse encephalopathy with confusion and agitation that lasted for about twenty-four hours. CONCLUSIONS: The prevalence of fat and bone-marrow-cell embolization was similar in the groups managed with bilateral simultaneous and unilateral total hip arthroplasty as well as in the groups managed with cemented and cementless stems.

Adult↗

Pulmonary embolism following shoulder arthroplasty.

BACKGROUND: While there have been numerous reports concerning the risk of pulmonary embolism after knee and hip arthroplasty, no such information is available for shoulder arthroplasty, as far as we know. The purpose of this study was to determine the prevalence of pulmonary embolism following shoulder arthroplasty. METHODS: A review of 2885 consecutive patients who underwent primary shoulder arthroplasty at our institution between June 30, 1981, and June 30, 2001, was performed to identify all patients who sustained a pulmonary embolism. RESULTS: During this time-period, five patients sustained a pulmonary embolism following shoulder arthroplasty. Three of the five presented with symptoms that were originally attributed to causes other than pulmonary embolism. None of the patients sustained a fatal pulmonary embolism. CONCLUSIONS: The data from this study demonstrate that pulmonary embolism is an uncommon complication of shoulder arthroplasty and that surgeons should have a high degree of suspicion if patients have respiratory difficulty following shoulder arthroplasty.

Adult↗

Enlargement of the right descending pulmonary artery in pulmonary embolism.

Pulmonary embolism often is undetected during life, even though adequate diagnostic procedures are available, probably because the condition is not suspected. Chest radiographs were reviewed for changes in the right descending pulmonary artery in 73 patients with confirmed pulmonary embolism and in 85 in whom the original suspicion subsequently was not confirmed. In embolic patients, the vessel, measured at four different levels starting from the superior venous angle, was larger during acute embolization than some weeks later. In particular, the two proximal diameters of descending pulmonary artery were significantly enlarged (p less than 0.01). This enlargement of the superior part was responsible for the shape modification of the vessel, which appeared to taper off sharply. Some weeks later, the artery took back its regular cone shape, tapering gently. In about one-fourth of the patients with pulmonary embolism, enlargement and shape modification were so marked that the artery showed a special "sausage" appearance. This feature did not occur in patients with unconfirmed suspicion of pulmonary embolism. Recognition of enlargement of the descending pulmonary artery may increase suspicion of pulmonary embolism; in particular, detection of "sausage" appearance of the vessel should identify patients with high probability of disease.

Adult↗

Abdominal myomectomy versus uterine fibroid embolization in the treatment of symptomatic uterine leiomyomas.

OBJECTIVE: The purpose of this study was to compare treatment efficacy and complications of abdominal myomectomy with those of uterine fibroid embolization in women with symptomatic uterine fibroids. MATERIALS AND METHODS: We analyzed the outcomes of 111 consecutive patients who underwent abdominal myomectomy (n = 44) or fibroid embolization (n = 67) over a 30-month period. The mean ages of the two groups were 37.7 years (range, 28-48 years) and 44.2 years (range, 31-56 years), respectively. A questionnaire and review of medical records assessed all procedure-related complications and changes in symptoms. Length of hospital stay, time until resumption of daily activities, and pain medication requirements after the procedure were also analyzed. RESULTS: Follow-up times for the myomectomy and embolization groups were 14.6 and 14.3 months, respectively. The respective observed success rates in abdominal myomectomy and uterine fibroid embolization patients were 64% versus 92% for menorrhagia (p < 0.05), 54% versus 74% for pain (not significant), and 91% versus 76% for mass effect (p < 0.05). The complication rates were 25% (abdominal myomectomy) and 11% (uterine fibroid embolization) (p < 0.05). The respective secondary end points for the two procedures were 2.9 versus 0 days mean hospital stay, 8.7 versus 5.1 days of narcotics use, and 36 versus 8 days until resumption of normal activities. These differences were all statistically significant. CONCLUSION: Uterine fibroid embolization is a less invasive and safer treatment option in women with symptomatic leiomyomas than myomectomy. Menorrhagia may be better controlled with embolization, and myomectomy may be a better option in patients with mass effect. Both procedures were equally effective in controlling pain.

Abdomen↗

Adenomyosis: MRI of the uterus treated with uterine artery embolization.

OBJECTIVE: The purpose of this study was to determine the MRI features seen after uterine artery embolization and to evaluate the clinical response in patients with adenomyosis. MATERIALS AND METHODS: Thirty women with adenomyosis underwent uterine artery embolization and follow-up MRI for 1 year. Of the 30, 27 patients were diagnosed with uterine fibroids and adenomyosis on the basis of MRI before uterine artery embolization. In six of the 27 patients, the dominant disease was adenomyosis. Three of the 30 patients had adenomyosis alone. The distribution, thickness, and enhancement of adenomyosis were analyzed in each patient. Patients completed a symptom questionnaire. RESULTS: After uterine artery embolization, the junctional zone-myometrial ratio did not change significantly. There were regions of devascularization of adenomyosis on contrast-enhanced images in 12 patients, all with a junctional zone thickness before uterine artery embolization of more than 20 mm (mean thickness, 39.2 mm). Eleven of the 12 patients had focal or asymmetric distribution patterns of adenomyosis. All three patients with pure adenomyosis and all six patients with dominant adenomyosis reported an improvement in symptoms. CONCLUSION: In patients treated with uterine artery embolization, MRI shows changes in areas of adenomyosis with a decrease in junctional zone vascularity in patients with thickening of the junctional zone greater than 20 mm. Devascularization may be related to the distribution of adenomyosis. The presence of adenomyosis should not be used as a contraindication to uterine artery embolization because most patients show clinical improvement after undergoing this procedure.

Adult↗

Percutaneous arterial embolization and chemoembolization for treatment of benign and malignant tumors in three dogs and a goat.

The term bland arterial embolization refers to catheter-directed delivery of particulate material for the purpose of embolizing selected arteries. This technique is used in humans to treat a number of conditions, including arteriovenous malformations, uterine fibroids, and epistaxis. The term chemoembolization refers to selective intra-arterial delivery of chemotherapeutic agents in conjunction with particulate material for the purpose of embolizing arteries supplying blood to a tumor. Compared with traditional modes of drug delivery, chemoembolization increases local concentration and dwell time of the chemotherapeutic agent, augments tumor ischemia, and minimizes systemic toxic effects. In humans, the technique has shown encouraging results in the treatment of a variety of nonresectable tumors. The present report describes techniques for percutaneous bland arterial embolization and chemoembolization in dogs and goats and results of these techniques in 3 dogs and a goat. Bland arterial embolization was performed in 2 dogs and the goat. The goals of treatment included pain palliation, reduction of tumor growth, and control of hemorrhage, and each animal was considered to have benefited from the procedure on the basis of the preprocedural goals. Chemoembolization was performed in 1 dog for treatment of a nonresectable hepatocellular carcinoma. Unfortunately, this dog did not live long enough to identify any response to treatment. Results for animals studied illustrate the feasibility of bland arterial embolization and chemoembolization in veterinary patients and suggest that embolization may provide an alternative method of treatment for animals with inoperable lesions.

Animals↗

Foreign-body pulmonary embolism.

The minimal incidence of pulmonary foreign-body embolism in a general pediatric pathology experience was ascertained by reviewing autopsy records, and the true incidence of pulmonary foreign-body embolism was determined by studying lung sections from 64 autopsies of patients who had undergone cardiac procedures. Seventeen cases of embolism were reported from 370 autopsies, an incidence of 4.6%. The true incidence of pulmonary foreign-body embolism was found to be 21.9% in the cardiac surgical autopsies and the minimal incidence was 5.1% in patients who had other types of surgery. No patients other than those having surgical procedures had embolism. Hair was found to be the embolic material in 35% of cases. Embolic lesions were characterized, staged, and correlated with clinical data. The pathogenesis of this condition is unclear, but it probably involves contamination of surgical materials with particulate matter.

Cardiac Surgical Procedures↗

Recanalization of spinal arteriovenous malformations following embolization.

Recently, therapeutic embolization has been advocated as the treatment of choice for arteriovenous malformations (AVM's) of the spine. However, no study has established lasting benefit from this procedure or determined the incidence of recanalization, as occurs with cerebral AVM's. In this study, six patients were followed periodically after complete obliteration of their AVM's by particulate embolization was shown by immediate arteriography. The study group included three men (aged 59 to 72 years) with spinal dural arteriovenous (AV) fistulas and three women (aged 27 to 38 years) with intramedullary glomus-type spinal cord AVM's. The patients were treated by embolization with 100- to 1000-microns diameter polyvinyl alcohol particles. Clinical improvement, most commonly manifesting as increased lower-extremity strength, occurred in all patients after embolization. However, recurrent symptoms, including weakness, numbness, and urinary incontinence, occurred within 2 and 8 months in two of the three patients with dural AV fistulas and within 2 months in two of the three patients with glomus AVM's, prompting radiological reevaluation. Spinal arteriography revealed recanalization of the AV fistulas and spinal AVM's in five patients. Magnetic resonance (MR) imaging demonstrated a signal-void area caused by intramedullary AVM's. This area disappeared after embolic occlusion, but recurred after delayed recanalization, indicating restored flow through the AVM. Embolization provides only temporary treatment for many spinal AVM's. After embolic occlusion, delayed reassessment with arteriography and/or MR imaging is indicated, particularly if the symptoms persist or recur. Surgical excision of spinal AVM's provides the only therapeutic means to eliminate flow through the AVM permanently in most patients, and should be considered the treatment of choice when feasible.

Aged↗

Evaluation of pressure changes in feeding arteries during embolization of intracerebral arteriovenous malformations.

The pressure in 47 arteries feeding 21 arteriovenous malformations (AVM's) was investigated during transarterial embolization using a Tracker-18 microcatheter. On average, systolic pressure increased by 22 mm Hg. In AVM's with single or few feeders, embolization was usually achieved well; in contrast, giant AVM's with multiple feeders and a large arteriovenous shunt were poorly embolized. However, large AVM's with well-demarcated components may be reduced by embolization to an appropriate size for surgery or stereotactic radiation therapy. It was found that the feeding artery pressure increased significantly more in well-embolized than in poorly embolized cases. Measurements of the feeding artery pressure clarified the hemodynamics of AVM's and facilitated more successful embolization.

Adolescent↗

A nonadhesive liquid embolic agent composed of ethylene vinyl alcohol copolymer and ethanol mixture for the treatment of cerebral arteriovenous malformations: experimental study.

OBJECT: The authors have developed a mixture of ethylene vinyl alcohol copolymer (EVAL) and iopamidol, which is dissolved in ethanol, as an alternative solvent to provide a safe means of embolizing arteriovenous malformations (AVMs). METHODS: A two-stage delivery technique is required to prevent premature precipitation in the catheter when using this material: the catheter is first infused with 30% ethanol and this is followed by the delivery of the EVAL-ethanol mixture. Acute angiographic changes were analyzed after superselective delivery of dimethyl sulfoxide (DMSO) and 30% ethanol into the renal artery of rabbits. Histological changes following the embolization of the renal artery achieved using the EVAL-ethanol mixture were recorded at 1 hour and at 2 and 16 weeks after the procedure. Although DMSO always produced severe, rapidly progressive vasospasm in the renal artery during a 1- to 60-minute postinfusion, 30% ethanol did not. Microscopically, the lumens of embolized vessels examined 1 hour after embolization with EVAL-ethanol appeared to be filled with EVAL sponges, leaving almost no open spaces. The space between the EVAL sponges and the inner surface of the vessels was filled with fresh thrombus. In the vessel walls of specimens examined 2 weeks after embolization there was no or a slight inflammatory reaction. Scattered in the EVAL sponges were almost equal numbers of neutrophilic granulocytes and mononuclear cells, indicative of a mild inflammatory response. In specimens examined 16 weeks postembolization, the changes noted at 2 weeks were intensified. There was no definite histopathological evidence of mural hemorrhage, perivascular extravasation of the mixture, or perivascular hemorrhage in any specimen that was examined. CONCLUSIONS: Although the degree of permanence of this embolization material is yet unknown, the mixture was easy to handle, and appeared safe and effective for AVM embolization. Its nonadhesive characteristic and its ability to be infused by repeated injections make it an attractive alternative to currently available materials. The good results obtained in this study led us to undertake a clinical trial, the results of which are contained in a companion article in this issue of the Journal of Neurosurgery.

Animals↗

Complications of preoperative embolization of cerebral arteriovenous malformations.

OBJECT: Preoperative embolization is viewed by the authors as a useful adjunct in the surgical management of cerebral arteriovenous malformations (AVMs). This study was performed to determine the rate of significant complication in patients undergoing this procedure. METHODS: Demographic, anatomical, and procedure data were collected prospectively. The treating physician reported complications. In addition, a review of medical records including procedure reports, operative reports, and discharge summaries was performed. Univariate statistical analysis was performed to determine if any of the variables was predictive of a poor outcome of embolization (death or permanent neurological deficit). Endovascular procedures for embolization were performed 339 times in 201 patients during an 11-year period. Female patients comprised 53.7% of the study group and 85.6% of the AVMs were supratentorial. Embolization was performed using polyvinyl alcohol particles, N-butyl cyanoacrylate, detachable coils, and/or the liquid polymer Onyx. Analyzed by procedure, a poor result of embolization occurred in 7.7%. Analyzed by patient, 11% died or had a permanent neurological deficit as a result of the embolization. None of the demographic, anatomical, or procedure variables identified were predictive of a poor outcome. CONCLUSIONS: Preoperative embolization may gradually reduce flow to an AVM, reduce intraoperative blood loss, and reduce operative time. The risks of this procedure, however, are not insignificant and must be considered in planning treatment for patients with AVMs.

Adolescent↗

MRI features of infarcts with potential cardiac source of embolism in the Yonsei Stroke Registry (YSR), Korea.

The determination of the embolic source is crucial to understanding the pathogenesis of ischemic stroke, the initiation of appropriate therapy, and the prevention of recurrent infarctions. In this study we undertook to identify the characteristic features on magnetic resonance images of patients who had suffered from stroke due to cardiac embolism (CE), as classified by TOAST (possible and probable). We retrospectively studied magnetic resonance imaging (MRI) findings of patients with ischemic stroke from the Yonsei Stroke Registry (YSR). On the basis of the TOAST classification, 92 patients were identified to have a potential cardiac source of embolism (PCSE), in which 69 patients were found to have high-risk PCSE and 23 patients medium-risk PCSE. To compare their imaging characteristics, another group of 49 patients who were found to have had a stroke due to large artery-to-artery (ATA) embolism-common or internal carotid artery (CCA, ICA)-were identified. Involvement of the simultaneous superficial and deep territories (58.7%; 6.1%, p < 0.001), and combined new anterior and old posterior circulation (15.2%; 2.0%, p = 0.016) were more frequent in PCSE than ATA embolism. Bilateral anterior hemispheric involvement was also more frequent in the PCSE group, but it did not reach statistical significance (13.0%; 4.1%, p = 0.090). ATA embolism tended to involve only superficial territories compared to PCSE (71.4%; 28.3%, p < 0.001). There were no topographic differences between the high-risk and medium-risk groups. With respect to the etiology of PCSE in our population, atrial fibrillation was the most common. Characteristic MRI features of patients with PCSE, which were not documented previously by computed tomography (CT) included: old and new, involvement of multiple different vascular territories, bilateral anterior hemisphere, as well as anterior and posterior circulation. These MRI features, together with simultaneous superficial and deep territorial involvement, help to differentiate the underlying embolic sources, whether they are cardiac or ATA in origin.

Cerebral Infarction↗

Uterine arterial embolization for the treatment of uterine leiomyomas.

OBJECTIVE: The purpose of this study was to establish guidelines for using uterine artery embolization for the treatment of uterine leiomyomas accompanied by adenomyosis in Korea. This study was performed to investigate 1) the effects of uterine embolization on leiomyoma accompanied by adenomyosis, 2) the outcome of uterine embolization according to the embolization materials used, 3) the relationship between the Resistance Index (RI) and the change in uterine volume. MATERIALS AND METHODS: We performed a retrospective study on 37 women who had uterine leiomyomas accompanied by adenomyosis. Bilateral uterine artery embolization was performed over a period of 17 months in 37 patients (age range 25 - 65) experiencing pain, hypermenorrhea, urinary frequency, etc. due to leiomyomas. Ultrasound imaging was performed before the procedure and at mean 6.9 months after the procedure. RESULTS: All procedures were technically successful. Mean clinical follow-up time was 12.8 months. Minor complications occurred in 82% patients following the procedure. After follow-up imaging, the median uterine volume decreased by 34.4% and the dominant myoma volume decreased by 86%. There was no statistical difference in the uterine volume reduction and the dominant myoma size reduction, whether the occluding agent was polyvinyl alcohol, polyvinyl alcohol plus gelfoam, or gelfoam, and whether the ultrasound measured Resistance Index value before the procedure was low or high. CONCLUSION: Primary candidates for uterine artery embolization include those with symptomatic uterine leiomyomas, who no longer desire fertility, but who wish to avoid surgery or are poor surgical risks. According to the results of our study, adenomyosis should not be considered as a contraindication for uterine artery embolization. However, because little data is available about the subsequent reproductive potential following this procedure, it should not be routinely advocated for infertile women. Further investigation is warranted regarding the choice of occluding agent and the role of the Resistance Index.

Adult↗

Pulmonary embolism associated with acute stroke.

OBJECTIVE: To describe the circumstances surrounding pulmonary embolism associated with stroke, the prophylactic measures, and the outcome in affected patients. MATERIAL AND METHODS: We studied pulmonary embolism in patients with acute stroke at Mayo Clinic Rochester during a 2-decade period. Medical records of 30 patients with pulmonary embolus after stroke were reviewed. Pulmonary embolus was diagnosed on the basis of pulmonary angiograms, high-or intermediate-probability ventilation-perfusion scans, or autopsy findings. RESULTS: Sudden death occurred in 15 of 30 patients (50%) with pulmonary embolism. In the other 15 patients, pleuritic pain or dyspnea was a major initial symptom. Pulmonary embolism occurred from day 3 to day 120 (median time, day 20) after the ictus. Prophylaxis against deep venous thrombosis was noted in only 4 of 30 patients. Pulmonary embolism was associated with deep venous thrombosis diagnosed clinically or at autopsy in 11 patients, invariably in the paralyzed leg. CONCLUSION: Pulmonary embolism after ischemic or hemorrhagic stroke may defy antemortem diagnosis in half of the affected patients. Pulmonary embolism in patients with acute stroke can be a cause of early mortality (during the first month after the ictus).

Acute Disease↗

The venous stasis syndrome after deep venous thrombosis or pulmonary embolism: a population-based study.

OBJECTIVES: To estimate the incidence and determine predictors of venous stasis syndrome and venous ulcers after deep venous thrombosis and pulmonary embolism. PATIENTS AND METHODS: This population-based retrospective cohort study reviewed medical records of 1527 patients with incident deep venous thrombosis or pulmonary embolism between 1966 and 1990. We recorded baseline characteristics, event type (deep venous thrombosis with or without pulmonary embolism or pulmonary embolism alone), leg side and site of deep venous thrombosis (proximal with or without distal deep venous thrombosis vs distal deep venous thrombosis alone), and venous stasis syndrome and venous ulcer. RESULTS: Two hundred forty-five patients developed venous stasis syndrome. One-year, 5-year, 10-year, and 20-year cumulative incidence rates were 7.3%, 14.3%, 19.7%, and 26.8%, respectively. By 20 years the cumulative incidence of venous ulcers was 3.7%. Patients with deep venous thrombosis with or without pulmonary embolism were 2.4-fold (95% confidence interval, 1.7-fold-3.2-fold) more likely to develop venous stasis syndrome than patients with pulmonary embolism and no diagnosed deep venous thrombosis. In patients aged 40 years or younger with proximal compared with distal-only deep venous thrombosis, venous stasis syndrome was 3.0-fold more likely (95% confidence interval, 1.6-fold-4.7-fold). In patients with unilateral leg deep venous thrombosis, venous stasis syndrome usually developed in the concordant leg (P < .001). There was a 30% (95% confidence interval, 2%-62%) increased risk for venous ulcer per decade of age at the incident venous thromboembolism. CONCLUSIONS: The cumulative incidence of venous stasis syndrome continues to increase for 20 years after venous thromboembolism. Pulmonary embolism alone is less likely to cause venous stasis syndrome.

Adult↗

Sensitivity and specificity of the semiquantitative latex agglutination D-dimer assay for the diagnosis of acute pulmonary embolism as defined by computed tomographic angiography.

OBJECTIVE: To determine the sensitivity and specificity of the semiquantitative latex agglutination plasma fibrin D-dimer assay for the diagnosis of acute pulmonary embolism by using computed tomographic (CT) angiography as the diagnostic reference standard. PATIENTS AND METHODS: From January 1, 1998, to June 26, 2000, patients who had both semiquantitative latex agglutination plasma fibrin D-dimer testing and CT angiography for suspected acute pulmonary embolism were selected for the study. A D-dimer value greater than 250 ng/mL was considered positive for thromboembolic disease. Diagnosis of acute pulmonary embolism was based solely on the interpretation of the CT angiogram. The D-dimer assay results were then compared with the CT angiographic diagnoses. RESULTS: Of 946 CT studies, 172 (18%) were positive for acute pulmonary embolism. The D-dimer assay was positive for 612 (65%) of the 946 patients. For acute pulmonary embolism, the D-dimer assay had a sensitivity of 0.83 (95% confidence interval [CI], 0.76-0.88), a specificity of 039 (95% CI, 036-0.43), a negative likelihood ratio of 0.44 (95 % CI, 032-0.62), and a negative predictive value of 0.91 (95% CI, 0.87-0.94). CONCLUSIONS: The semiquantitative latex agglutination plasma fibrin D-dimer assay had moderate sensitivity and low specificity for the diagnosis of acute pulmonary embolism. When used alone, the results of this test were insufficient to exclude this serious and potentially fatal disorder. Approximately two thirds of our patients had positive D-dimer assays and required further evaluation to exclude acute pulmonary embolism.

Adolescent↗

Diagnostic utility of ultrasonography of leg veins in patients suspected of having pulmonary embolism.

BACKGROUND: The standard diagnostic approach in patients suspected of having pulmonary embolism starts with perfusion-ventilation lung scanning. If the resulting scan is not diagnostic, pulmonary angiography should be done. The use of tests for deep venous thrombosis has been advocated as an adjunct to establishing the diagnosis of pulmonary embolism, but no prospective studies have provided adequate information about the value of these tests. OBJECTIVE: To determine the accuracy and potential clinical utility of compression ultrasonography in the diagnosis of pulmonary embolism. DESIGN: Prospective cohort study with blinded assessment of ultrasonographic results. SETTING: Teaching hospital. PATIENTS: 397 consecutive inpatients and outpatients in whom pulmonary embolism was clinically suspected. MEASUREMENTS: Sensitivity and specificity of compression ultrasonography. Perfusion-ventilation scanning and angiography were the conjoint gold standard for determining the presence or absence of pulmonary embolism. Also calculated were the number of angiograms and lung scans avoided and the number of patients unnecessarily treated when compression ultrasonography was included in the diagnostic strategy. RESULTS: The overall sensitivity of compression ultrasonography for deep venous thrombosis in patients with pulmonary embolism was 29% (95% CI 22% to 37%); the specificity was 97% (CI, 94% to 99%). Adding ultrasonography to the diagnostic approach before lung scanning would avoid approximately 14% of lung scans and 9% of angiograms but would lead to unnecessary treatment of 13% of patients who have an abnormal ultrasonographic result (2% to 4% of all those receiving anticoagulation). When compression ultrasonography is done only in patients with a nondiagnostic lung scan, 9% of angiographies are prevented at the cost of unnecessarily treating 26% of patients who have an abnormal ultrasonographic result (2% of all patients receiving anticoagulation). CONCLUSION: The diagnostic value of compression ultrasonography for the detection of deep venous thrombosis in patients suspected of having pulmonary embolism is limited; the gain in diagnostic efficiency obtained through the use of ultrasonography may be offset by a loss in diagnostic accuracy.

Adolescent↗

Performance of helical computed tomography in unselected outpatients with suspected pulmonary embolism.

BACKGROUND: Helical computed tomography (CT) is commonly used to diagnose pulmonary embolism, although its operating characteristics have been insufficiently evaluated. OBJECTIVE: To assess the sensitivity and specificity of helical CT in suspected pulmonary embolism. DESIGN: Observational study. SETTING: Emergency department of a teaching and community hospital. PATIENTS: 299 patients with clinically suspected pulmonary embolism and a plasma D -dimer level greater than 500 microgram/L. INTERVENTION: Pulmonary embolism was established by using a validated algorithm that included clinical assessment, lower-limb compression ultrasonography, lung scanning, and pulmonary angiography. MEASUREMENTS: Sensitivity, specificity, and likelihood ratios of helical CT and interobserver agreement. Helical CT scans were withheld from clinicians and were read 3 months after acquisition by radiologists blinded to all clinical data. RESULTS: 118 patients (39%) had pulmonary embolism. In 12 patients (4%), 2 of whom had pulmonary embolism, results of helical CT were inconclusive. For patients with conclusive results, sensitivity of helical CT was 70% (95% CI, 62% to 78%) and specificity was 91% (CI, 86% to 95%). Interobserver agreement was high (kappa = 0.823 to 0.902). The false-negative rate was lower for helical CT used after initial negative results on ultrasonography than for helical CT alone (21% vs. 30%). Use of helical CT after normal results on initial ultrasonography and nondiagnostic results on lung scanning had a false-negative rate of only 5% and a false-positive rate of only 7%. CONCLUSION: Helical CT should not be used alone for suspected pulmonary embolism but could replace angiography in combined strategies that include ultrasonography and lung scanning.

Adult↗