Emergency department diagnosis of pulmonary embolism is associated with significantly reduced mortality: A linked data population study

Objectives: We characterized patients admitted via ED with a principal hospital discharge diagnosis of pulmonary embolism (PE) and compared mortality of those diagnosed in the ED with those diagnosed after admission. Methods: Patients with a hospital discharge diagnosis ICD 10 I26 presenting to the ED in Perth, Western Australia between 1 July 2000 and 30 December 2006 had records from the Emergency Department Information System linked to the Western Australian Hospital Morbidity Data System and the death registry. Results: Of 2250 patients (mean age 60.4), 1227 (54.5%) were female. Of 1931 patients with an ED diagnosis recorded, 1207 (62.5%) were diagnosed with PE in ED. Of these, 383 (17.0%) had presented to an ED within 28 days previously, 142 (37.1%) with either chest pain or breathing problems, with 207 (54.0%) admitted but not receiving a principal hospital discharge diagnosis of PE. There were 127 (5.6%) in‐hospital deaths. Controlling for age and comorbidity with logistic regression, patients diagnosed with PE in ED were less likely to die in hospital, within 7 and 30 days of ED arrival, than those diagnosed after admission (adjusted OR 0.31, 95% CI 0.20–0.47; adjusted OR 0.32, 95% CI 0.19–0.53; adjusted OR 0.30, 95% CI 0.20–0.44; respectively). Conclusion: Making the diagnosis of PE in ED was associated with a substantial survival advantage that persisted after hospital discharge.     

Computed tomography pulmonary angiography in the diagnosis of acute pulmonary embolism in the emergency department

This study was undertaken to evaluate the use of computed tomography pulmonary angiography (CTPA) in patients with pulmonary embolism (PE) who were followed in the emergency department (ED). The files and computer records of 850 patients older than 16 years of age who were seen in the Hacettepe University Hospital ED between April 10, 2001, and December 1, 2005, and who required CTPA for PE prediagnosis and/or another diagnosis, were studied retrospectively. PE was identified by CTPA in 9.4% of 416 women and in 5.8% of 434 men. A significant difference (P< .05) was noted in the women and men in whom PE was detected. The mean age of the patients was 58.13±17.88 y (range, 16–100 y). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for clinical susceptibility to PE among patients who underwent CTPA were assessed at 95.3%, 48.2%, 13%, and 99.2%, respectively. CTPA was done for different reasons: aortic aneurysm dissection (n=1), cough distinctive diagnosis (n=1), dyspnea distinctive diagnosis (n=6), chest pain distinctive diagnosis (n=3), PE prediagnosis (n=51), and other reasons (n=2). Also, sensitivity, specificity, PPV, and NPV were found to be 95.4%, 16.2%, 14.4%, and 96%, respectively, for D-dimer. CTPA, which is accessible on a 24-h basis in the ED, is a valuable tool for the diagnosis of PE.     

Use of spiral computed tomography contrast angiography and ultrasonography to exclude the diagnosis of pulmonary embolism in the emergency department

Spiral computed tomography (CT) contrast angiography is a promising imaging modality for the diagnosis of pulmonary embolism but the negative predictive value of this test remains controversial. We performed a multi-center prospective cohort study to determine the safety of relying on a negative spiral CT contrast angiography scan to exclude pulmonary embolism. Patients presenting to the Emergency Departments of three tertiary care institutions with clinically suspected pulmonary embolism were potentially eligible for the study. Patients underwent a clinical evaluation to categorize pretest probability into low, moderate, and high categories, and had D-dimer testing performed. Patients at low pretest probability with normal D-dimer were considered to have pulmonary embolism excluded. The remaining patients underwent spiral CT contrast angiography scan of the pulmonary arterial circulation and bilateral venous ultrasound of the proximal leg veins. Patients who were confirmed to have pulmonary embolism or deep vein thrombosis were treated with anticoagulant therapy. Patients in whom the diagnosis of pulmonary embolism was excluded did not receive anticoagulant therapy and were followed for a 3-month period for the development of venous thromboembolic complications. Eight hundred fifty-eight (858) patients were enrolled in this study. Three-hundred sixty-nine (369) patients had low pretest probability and negative D-dimer results and no further diagnostic tests were performed. None of these patients subsequently developed venous thromboembolic complications (0%, 95% confidence interval [CI] 0% to 1.0%). The remaining 489 were referred for spiral CT contrast angiography scan and ultrasound. Sixty-seven patients were confirmed to have pulmonary embolism and an additional 15 patients with negative CT scans had proximal deep vein thrombosis (DVT) on ultrasound for a total prevalence of venous thromboembolism of 82/489 (16.8%). Two of 409 patients who had pulmonary embolism excluded in the initial evaluation phase developed proximal venous thromboembolism (0.5%; 95% CI 0% to 1.8%) in the 3-month follow-up period. These findings suggest that the combination of a negative spiral CT contrast angiography scan and normal venous ultrasound imaging safely excludes the diagnosis of pulmonary embolism in the Emergency Department setting.     

Investigating pulmonary embolism in the emergency department with lower limb plethysmography: the Manchester Investigation of Pulmonary Embolism Diagnosis (MIOPED) study

Objectives

To measure the diagnostic accuracy of computerised strain gauge plethysmography in the diagnosis of pulmonary embolism (PE).

Methods

Two researchers prospectively recruited 425 patients with pleuritic chest pain presenting to the emergency department (ED). Lower limb computerised strain gauge plethysmography was performed in the ED. All patients underwent an independent reference standard diagnostic algorithm to establish the presence or absence of PE. A low modified Wells'' clinical probability combined with a normal D‐dimer excluded PE. All others required diagnostic imaging with PIOPED interpreted ventilation perfusion scanning and/or computerised tomography (CT) pulmonary angiography. Patients with a nondiagnostic CT had digital subtraction pulmonary angiography. All patients were followed up clinically for 3 months.

Results

The sensitivity of computerised strain gauge plethysmography was 33.3% (95% confidence interval (CI) 16.3 to 56.2%) and specificity 64.1% (95% CI 59.0 to 68.8%). The negative likelihood ratio was 1.04 (95% CI 0.68 to 1.33) and positive likelihood ratio 0.93 (95% CI 0.45 to 1.60).

Conclusions

Lower limb computerised strain gauge plethysmography does not aid in the diagnosis of PE.     

European and American suspected and confirmed pulmonary embolism populations: comparison and analysis

Summary. Background: If the prevalence of pulmonary embolism (PE) differs significantly between the US and Europe, this observation could reduce the generalizability of diagnostic protocols for PE derived in either location.Objective: To determine possible causes and potential clinical consequences of these PE prevalence differences.Methods: Secondary analysis of three prospectively collected multicenter samples (two French and one from the US) including 3174 European and 7940 American PE‐suspected patients in Emergency departments (ED) (117 for Europe and 12 for US). Comparison of clinical features, resource use and outcomes of European‐ and US‐suspected PE populations in ED.Results: European patients evaluated for PE were significantly older and had a higher clinical pretest probability (CPP) for PE. The final PE prevalence was significantly higher in Europe, in the overall sample (26.5% vs. 7.6%) and in each level of CPP. Suspected European patients categorized as low CPP had a higher posttest probability than US low CPP patients. Suspected US patients categorized as high CPP had a much lower posttest probability of PE than in Europe. The mean number of tests performed for one PE diagnosis was lower in Europe (7.4 vs. 21.6). Among patients diagnosed with PE, European patients had a higher mean severity of illness score and a higher PE‐mortality rate (3.4% vs. 0.7%).Conclusions: Among patients suspected of a PE and those ultimately diagnosed with a PE, European patients had higher acuity, a higher pretest probability and worse outcome than US patients. The present study underscores the importance of disease prevalence for pretest probability scoring approaches and for significance interpretation of imaging tests.     

Clinical probability and alveolar dead space measurement for suspected pulmonary embolism in patients with an abnormal D-dimer test result

BACKGROUND: Most patients with suspected pulmonary embolism (PE) have a positive D-dimer test and undergo diagnostic imaging. Additional non-invasive bedside tests are required to reduce the need for further diagnostic tests. OBJECTIVES: We aimed to determine whether a combination of clinical probability assessment and alveolar dead space fraction measurement can confirm or exclude PE in patients with an abnormal D-dimer test. METHODS: We assessed clinical probability of PE and alveolar dead space fraction in 270 consecutive in- and outpatients with suspected PE and positive D-dimer. An alveolar dead space fraction < 0.15 was considered normal. PE was subsequently excluded or confirmed by venous compression ultrasonography, spiral computed tomography and a 3-month follow-up. Radiologists were unaware of the results of clinical probability and capnography. RESULTS: PE was confirmed in 108 patients (40%). Capnography had a sensitivity of 68.5% (95% confidence interval [CI]: 58.9-77.1%) and a specificity of 81.5% (95% CI: 74.6-87.1%) for PE. Forty-five patients (16.6%) had both a low clinical probability and normal capnography (sensitivity: 99.1%, 95% CI: 94.9-100%) and 34 patients (12.6%) had both a high clinical probability and abnormal capnography (specificity: 100%, 95% CI: 97.7-100%). CONCLUSION: Capnography alone does not exclude PE accurately. The combination of clinical probability and capnography accurately excludes or confirms PE and avoids further testing in up to 30% of patients.     

Diagnostic management of clinically suspected acute pulmonary embolism

Summary.  Current diagnostic management of hemodynamically stable patients with clinically suspected acute pulmonary embolism (PE) consists of the accurate and rapid distinction between the approximate 20–25% of patients who have acute PE and require anticoagulant treatment, and the overall majority of patients who do not have the disease in question. Clinical outcome studies have demonstrated that, using algorithms with sequential diagnostic tests, PE can be safely ruled out in patients with a clinical probability indicating PE to be unlikely and a normal D-dimer test result. This obviates the need for additional radiological imaging tests in 20–40% of patients. CT pulmonary angiography (CTPA) has become the first line tool to confirm or exclude the diagnosis of PE in patients with a likely probability of PE or an elevated D-dimer blood concentration. While single-row-detector technology CTPA has a low sensitivity for PE and bilateral compression ultrasound (CUS) of the lower limbs is considered necessary to rule out PE, multi-row-detector CTPA is safe to exclude PE without the confirmatory use of CUS.     

Tandem measurement of D-dimer and myeloperoxidase or C-reactive protein to effectively screen for pulmonary embolism in the emergency department

OBJECTIVES: The hypothesis was that the tandem measurement of D-dimer and myeloperoxidase (MPO) or C-reactive protein (CRP) could significantly decrease unnecessary pulmonary vascular imaging in emergency department (ED) patients evaluated for pulmonary embolism (PE) compared to D-dimer alone. METHODS: The authors measured the sequential combinations of D-dimer and MPO and D-dimer and CRP in a prospective sample of ED patients evaluated for PE at two centers. Patients were followed for 90 days for venous thromboembolism (VTE, either PE or deep venous thrombosis [DVT]), which required the consensus of two of three blinded physician reviewers. RESULTS: The authors enrolled 304 patients, 22 with VTE (7%; 95% confidence interval [CI] = 5% to 10%). The sensitivity and specificity of a D-dimer alone (cutoff > or = 500 ng/mL) were 100% (95% CI = 85% to 100%) and 59% (95% CI = 53% to 65%), respectively, and was followed by pulmonary vascular imaging negative for PE in 38% (115/304; 95% CI = 32% to 44%). The combination of either a negative D-dimer, or MPO < 22 mg/dL, had a sensitivity of 100% and specificity of 73% (95% CI = 67% to 78%). Thus, tandem measurement of D-dimer and MPO would have decreased the frequency of subsequent negative pulmonary vascular imaging from 38% to 25% (95% CI of the difference of -13% = -5% to -20%). The combination of CRP and D-dimer would not have significantly improved the rate of negative imaging. CONCLUSIONS: The tandem measurement of D-dimer and MPO would have significantly decreased negative pulmonary vascular imaging compared with D-dimer alone and should be validated prospectively.     

Extracorporeal CPR for massive pulmonary embolism in a “hybrid 2136 emergency department”

AimPatients with massive pulmonary embolism (PE) have poor outcomes and their management remains challenging. An interventional radiology (IVR)-computed tomography (CT) system available in our emergency room (ER) allows immediate access to CT and extracorporeal membrane oxygenation (ECMO) with safe cannulation under fluoroscopy. We aimed to determine if initial treatment in this “hybrid ER” is helpful in patients with PE requiring extracorporeal cardiopulmonary resuscitation (ECPR).MethodsThe records of patients transferred to our hybrid ER between September 2014 and December 2017 who required ECPR for PE were reviewed.ResultsNine consecutive patients (median age 50 [range 30–76] years) with PE requiring ECPR were identified in our hybrid ER. Five (55.6%) had at least one risk factor for PE. Six (66.7%) experienced an out-of-hospital cardiac arrest and 3 (33.3%) had a cardiac arrest in the hybrid ER. Right ventricular overload was detected on electrocardiography and bedside transthoracic echocardiography in all cases. The median pH, lactate, PaCO₂, and HCO₃ values on arterial blood gas analysis in the hybrid ER were 7.01 (6.68–7.26), 14 (8–22) mmol l⁻¹, 44.7 (23.8–60.5) mmHg, and 10.4 (6.7–14.1), respectively. Four patients (44.4%) received monteplase for thrombolysis. No patient underwent surgical embolectomy. The median duration of ECMO was 69 (38–126) h. There were two ECMO-related bleeding complications. Eight patients (88.9%) survived and one died of post-resuscitation encephalopathy after weaning from ECMO.ConclusionA hybrid ER may be useful for initial management of massive PE requiring ECPR and may help to improve outcomes.     

Emergency department focused bedside echocardiography in massive pulmonary embolism

Background

Massive pulmonary embolism (PE) is a common consideration in unstable patients presenting to the emergency department (ED) with chest pain, dyspnea, or cardiac arrest. It is a potentially lethal condition necessitating prompt recognition and aggressive management. Conventional diagnostic modalities in the ED, including chest computed tomography angiography and ventilation-perfusion scanning, require the unstable patient to leave the department, and raise concerns over renal injury. Several case reports document findings of massive PE on echocardiography performed in the ED; however, none was performed, interpreted, and acted upon in the form of thrombolytic therapy by an emergency physician without the additional benefit of a cardiologist’s interpretation or a confirmatory imaging study.

Objective

We present a case that illustrates the utility of ED focused bedside echocardiography in suspected massive PE and briefly review direct and indirect ultrasound findings of acute PE.

Case Report

A case of massive PE in a 61-year-old woman is reported. In this patient with marked dyspnea, progressive hemodynamic instability, and contraindications to definitive imaging, ED focused bedside echocardiography provided valuable information that strongly suggested the diagnosis and led to alteplase administration. To our knowledge, this case represents the first report of thrombolytic therapy administration for acute massive PE based solely on clinical presentation and an emergency physician-performed bedside echocardiogram.

Conclusion

In the hands of an experienced emergency physician ultrasonographer, ED focused bedside echocardiography provides a safe, rapid, and non-invasive diagnostic adjunct for evaluation of the patient suspected of having massive PE.     

Reduced access block causes shorter emergency department waiting times: An historical control observational study

Objective: To study the effect of changes in hospital occupancy and ED occupancy on ED waiting times during a 13‐day period of improved bed access. Methods: A comparative, observational study of 1133 ED attendances in the study period and 2332 attendances in a historical control period. Results: During the study period, mean hospital occupancy decreased from 94.9% to 89.0% (P < 0.001), mean ED occupancy decreased from 19.1 to 14.8 patients (P < 0.001) and the mean ED waiting time decreased from 58.5 to 37.1 min (P < 0.001). There were statistically significant reductions in waiting times for patients in Australasian triage scale (ATS) categories 2–5. Departmental staffing levels, attendances and patient acuity were not significantly different during the study and control periods. Conclusions: Modest decreases in hospital occupancy resulted in highly significant reductions in ED waiting times. Emergency department overcrowding due to large numbers of admitted patients awaiting hospital admission is a major cause of ED dysfunction.     

Clinical criteria to prevent unnecessary diagnostic testing in emergency department patients with suspected pulmonary embolism.

Overuse of the d-dimer to screen for possible pulmonary embolism (PE) can have negative consequences. This study derives and tests clinical criteria to justify not ordering a d-dimer. The test threshold was estimated at 1.8% using the method of Pauker and Kassirer. The PE rule-out criteria were derived from logistic regression analysis with stepwise backward elimination of 21 variables collected on 3148 emergency department patients evaluated for PE at 10 US hospitals. Eight variables were included in a block rule: Age < 50 years, pulse < 100 bpm, SaO(2) > 94%, no unilateral leg swelling, no hemoptysis, no recent trauma or surgery, no prior PE or DVT, no hormone use. The rule was then prospectively tested in a low-risk group (1427 patients from two hospitals initially tested for PE with a d-dimer) and a very low-risk group (convenience sample of 382 patients with chief complaint of dyspnea, PE not suspected). The prevalence of PE was 8% (95% confidence interval: 7-9%) in the low-risk group and 2% (1-4%) in the very low-risk group on longitudinal follow-up. Application of the rule in the low-risk and very low-risk populations yielded sensitivities of 96% and 100% and specificities of 27% and 15%, respectively. The prevalence of PE in those who met the rule criteria was 1.4% (0.5-3.0%) and 0% (0-6.2%), respectively. The derived eight-factor block rule reduced the pretest probability below the test threshold for d-dimer in two validation populations, but the rule's utility was limited by low specificity.     

Increasing use of CTPA for the investigation of suspected pulmonary embolism

Objectives: Pulmonary embolism (PE) is a frequently suspected life-threatening condition that often presents with non-specific signs and symptoms. There is concern that increased availability of computerized tomography pulmonary angiogram (CTPA) is resulting in overuse in the diagnostic workup of patients presenting with cardio-respiratory symptoms. We therefore aimed to determine whether use of CTPA was increasing over time within our institution, with a consequent decrease in the diagnostic yield of PE. Furthermore, we investigated the frequency of alternative (non-PE) pathological findings revealed by CTPA.

Methods: All patients who underwent CTPA in the first 15 days of eight consecutive years were enrolled retrospectively. Radiology reports and online medical records were examined. In addition, the rates of incidental PE from patients undergoing CT chest for non-suspected PE indications were also examined.

Results: An increasing use of CTPA was confirmed (p = 0.04). Despite this, the diagnostic yield of PE also increased (p = 0.03). Similarly, increasing numbers of patients underwent CT chest for non-PE indications, but in this group the rate of incidental PE remained static (~3.4%). In CPTA investigations that were negative for PE, common alternative findings were consolidation, pleural effusion and emphysema, with only 16.7% showing no abnormality.

Conclusion: Although CTPA use is increasing, so is the diagnostic yield of PE. In contrast, the rate of incidental PE in those undergoing a CT chest scan for non-PE diagnosis remains relatively low and stable. This suggests that our observed increased use of CTPA is clinically appropriate.     

Contrast nephropathy following computed tomography angiography of the chest for pulmonary embolism in the emergency department

OBJECTIVE: To estimate the frequency of contrast nephropathy after computed tomography angiography (CTA) to rule out pulmonary embolism (PE) in the emergency department (ED) setting. METHODS: We prospectively followed patients undergoing CTA for PE, while in the ED, for 45 days. Patients who refused follow-up or were receiving hemodialysis were excluded. Severe renal failure was defined as an increase in creatinine > or = 3.0 mg dL(-1) or a need for hemodialysis within the follow-up period. Patients were also followed for laboratory-defined contrast nephropathy, defined as an increase in creatinine of > 0.5 mg dL(-1) or > 25%, within seven days following CTA. RESULTS: A total of 1224 patients were followed, and 354 [29%, 95% confidence interval (CI): 26-32%] patients had paired (preCTA and post-CTA) creatinine measurements. None developed renal failure (0/1224; 0%, CI: 0-0.3%). 44 patients developed laboratory-defined contrast nephropathy, corresponding to an overall frequency of 4% (44/1224; CI: 3-5%) and 12% (44/354; 95% CI: 9-16%) among those with paired creatinine measurements. CONCLUSIONS: Following CTA for PE, the incidence of severe renal failure was very low, but the incidence of laboratory-defined contrast nephropathy (4% overall and 12% of those with paired measurements) was higher than expected.     

Diagnosis of pulmonary embolism with CT pulmonary angiography: a systematic review

Objective

To appraise the evidence on the diagnostic accuracy of CT pulmonary angiography and the prognostic value of a negative CT pulmonary angiogram in the diagnosis of pulmonary embolism.

Methods

Medline, EMBASE, and grey literature were systematically searched by two researchers. Any study which compared CT pulmonary angiography to an acceptable reference standard or prospectively followed up a cohort of patients with a normal CT pulmonary angiogram was included. Study methods were appraised independently by two researchers, and data were extracted independently by three researchers.

Results

Thirteen diagnostic and 11 follow up studies were identified. Studies varied in prevalence of pulmonary embolism (19–79%), patient groups, and method quality. Few studies recruited unselected emergency department patients. There was heterogeneity in the analysis of sensitivity (53 to 100%), specificity (79 to 100%), and false negative rate (1.0 to 10.7%). The pooled false negative rate of combined negative CT pulmonary angiography and negative deep vein thrombosis testing was 1.5% (95% CI 1.0 to 1.9%).

Conclusion

Diagnostic studies give conflicting results for the diagnostic accuracy of CT pulmonary angiography. Follow up studies show that CT pulmonary angiography can be used in combination with investigation for deep vein thrombosis to exclude pulmonary embolism.     

Outpatient diagnosis of pulmonary embolism: the MIOPED (Manchester Investigation Of Pulmonary Embolism Diagnosis) study

Background and objectives     

Review article: Sepsis in the emergency department – Part 1: Definitions and outcomes

Sepsis has recently been redefined as acute organ dysfunction due to infection. The ED plays a critical role in identifying patients with sepsis. This is challenging due to the heterogeneity of the syndrome, and the lack of an objective standard diagnostic test. While overall mortality rates from sepsis appear to be falling, there is an increasing burden of morbidity among survivors. This largely reflects the growing proportion of older patients with comorbid illnesses among those treated for sepsis.     

肺栓塞患者抗凝治疗的急救护理

对肺栓塞患者的急救和抗凝治疗的配合及护理特点进行探讨。介绍了肺栓塞的急救护理措施、抗凝治疗的观察要点及护理对策,肯定了密切观察心电图、血压．呼吸及血氧饱和度与抗凝治疗中的护理配合和做好出院指导的重要性。