Explaining COVID-19 related mortality disparities in American Indians and Alaska Natives.

American Indian and Alaska Native (AI/AN) individuals are more likely to die with COVID-19 than other groups, but there is limited empirical evidence to explain the cause of this inequity. The objective of this study was to determine whether medical comorbidities, area socioeconomic deprivation, or access to treatment can explain the greater COVID-19 related mortality among AI/AN individuals. The design was a retrospective cohort study of harmonized electronic health record data of all inpatients with COVID-19 from 21 United States health systems from February 2020 through January 2022. The mortality of AI/AN inpatients was compared to all Non-Hispanic White (NHW) inpatients and to a matched subsample of NHW inpatients. AI/AN inpatients were more likely to die during their hospitalization (13.2% versus 7.1%; odds ratio [OR] = 1.98, 95% confidence interval [CI] = 1.48, 2.65) than their matched NHW counterparts. After adjusting for comorbidities, area social deprivation, and access to treatment, the association between ethnicity and mortality was substantially reduced (OR 1.59, 95% CI 1.15, 2.22). The significant residual relation between AI/AN versus NHW status and mortality indicate that there are other important unmeasured factors that contribute to this inequity. This will be an important direction for future research.

Factors associated with 60-day readmission among inpatients with COVID-19 at 21 United States health systems.

Identifying patients at risk for readmission after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection could facilitate care planning and prevention. This retrospective cohort study of 60-day readmission included 105 543 COVID-19 patients at 21 US healthcare systems who were discharged alive between February 2020 and November 2021. Generalized linear mixed regression analyses tested predictors of 60-day readmission and severity. The all-cause readmission rate was 15% (95% confidence interval [CI] = 10%-21%), with 22% (95% CI = 18%-26%) of readmitted patients needing intensive care, and 6% (95% CI = 05%-07%) dying. Factors associated with readmission included male sex, government insurance, positive smoking history, co-morbidity burden, longer index admissions, and diagnoses at index admission (e.g., cancer, chronic kidney disease, and liver disease). Death and intensive care rates at readmission declined postvaccine availability. Receiving at least two COVID-19 vaccine doses, which were more common among older patients and those with comorbid conditions, was not independently associated with readmission but predicted a reduced risk of death at readmission. This retrospective cohort study identified factors associated with all-cause readmission for patients re-admitted to the same health system after hospitalization with SARS-CoV-2 infection. Patients who are male, who smoke, who have a higher comorbidity burden, and have government insurance may benefit from additional postacute care planning.

The association between pulmonary artery enlargement and mortality in an Emergency Department population undergoing computed tomography pulmonary angiography.

Findings of an enlarged pulmonary artery diameter (PAd) and increased pulmonary artery to ascending aorta ratio (PA:AA) on contrast-enhanced computed tomography pulmonary angiography (CTPA) are associated with increased mortality in particular groups of patients with cardiopulmonary disease. However, the frequency and prognostic significance of these incidental findings has not been studied in unselected patients evaluated in the Emergency Department (ED). This study aims to determine the prevalence and associated prognosis of enlarged pulmonary artery measurements in an ED cohort. We measured PA and AA diameters on 990 CTPA studies performed in the ED. An enlarged PA diameter was defined as >27 mm in females and >29 mm in males, while an increased PA:AA was defined as >0.9. Poisson regression was performed to calculate prevalence ratios for relevant comorbidities, and multivariable Cox regression was performed to calculate hazard ratios (HR) for mortality of patients with enlarged pulmonary artery measurements. An enlarged PAd was observed in 27.9% of 990 patients and was more commonly observed in older patients and in patients with obesity or heart failure. Conversely, PA:AA was increased in 34.2% of subjects, and was more common in younger patients and those with peripheral vascular disease or obesity. After controlling for age, sex, and comorbidities, both enlarged PAd (HR 1.29, 95% CI 1.00-1.68, p = 0.05) and PA:AA (HR 1.70, 95% CI 1.31-2.22 p < 0.01) were independently associated with mortality. In sum, enlarged PAd and increased PA:AA are common in patients undergoing CTPAs in the ED setting and both are independently associated with mortality.

A machine learning analysis of correlates of mortality among patients hospitalized with COVID-19.

It is vital to determine how patient characteristics that precede COVID-19 illness relate to COVID-19 mortality. This is a retrospective cohort study of patients hospitalized with COVID-19 across 21 healthcare systems in the US. All patients (N = 145,944) had COVID-19 diagnoses and/or positive PCR tests and completed their hospital stays from February 1, 2020 through January 31, 2022. Machine learning analyses revealed that age, hypertension, insurance status, and healthcare system (hospital site) were especially predictive of mortality across the full sample. However, multiple variables were especially predictive in subgroups of patients. The nested effects of risk factors such as age, hypertension, vaccination, site, and race accounted for large differences in mortality likelihood with rates ranging from about 2-30%. Subgroups of patients are at heightened risk of COVID-19 mortality due to combinations of preadmission risk factors; a finding of potential relevance to outreach and preventive actions.

The Relationship of COVID-19 Vaccination with Mortality Among 86,732 Hospitalized Patients: Subpopulations, Patient Factors, and Changes over Time.

BACKGROUND: Information on COVID-19 vaccination effects on mortality among patients hospitalized with COVID-19 could inform vaccination outreach efforts and increase understanding of patient risk. OBJECTIVE: Determine the associations of vaccination status with mortality in adult patients hospitalized with COVID-19. DESIGN: This retrospective cohort study assessed the characteristics and mortality rates of adult patients hospitalized with COVID-19 across 21 healthcare systems in the USA from January 1, 2021, to January 31, 2022. PARTICIPANTS: Adult patients admitted to participating hospitals who had COVID-19 diagnoses and/or positive PCR tests and completed their hospital stay via discharge or death. MAIN MEASURE: In-hospital mortality vs. discharge (outcome) and patient age, sex, race, ethnicity, BMI, insurance status, comorbidities, and vaccination status extracted from the electronic health record (EHR). KEY RESULTS: Of 86,732 adult patients hospitalized with COVID-19, 45,082 (52%) were female, mean age was 60 years, 20,800 (24%) were Black, and 22,792 (26.3%) had one or more COVID-19 vaccinations. Statistically adjusted mortality rates for unvaccinated and vaccinated patients were 8.3% (95% CI, 8.1-8.5) and 5.1% (95% CI, 4.8-5.4) respectively (7.9% vs. 4.5% with no immune compromise). Vaccination was associated with especially large reductions in mortality for obese (OR = 0.67; 95% CI 0.56-0.80) and severely obese (OR = 0.52; 95% CI, 0.41-0.67) patients and for older patients (OR = 0.99; 95% CI, 0.98-0.99). Mortality likelihood was higher later in the study period (August 2021-January 31, 2022) than earlier (January 1, 2021-July 30, 2021) (OR = 1.10; 95% CI = 1.04-1.17) and increased significantly for vaccinated patients from 4.6% (95% CI, 3.9-5.2%) to 6.5% (95% CI, 6.2-6.9%). CONCLUSIONS: Patients vaccinated for COVID-19 had reduced mortality, especially for obese/severely obese and older individuals. Vaccination's protective effect against mortality declined over time and hospitalized obese and older individuals may derive especially great benefit from prior vaccination against SARS-CoV-2.

The Bucket Approach: Developing and Implementing an On-line Training Program in Tobacco Dependence Interventions Tailored for Behavioral Health Clinicians.

People coping with a mental illness and/or addictive disorders have a very high prevalence of smoking cigarettes. The Bucket Approach, a free online training, tailors evidence-based tobacco dependence interventions for behavioral health clinicians to increase the likelihood that they will also address the tobacco use of their patients. From October 2019 through August 2021, 999 people enrolled in and 447 people completed the training. Individuals who completed the training evaluated it highly with an overall mean score of 8.4 (scale = 1 for very poor to 10 for very good). 3- and 6-month follow-up surveys documented continued impact. The training resulted in substantial changes in beliefs about treating tobacco dependence. For example, before training, 18.3% of trainees strongly agreed with the statement, "The skills currently possessed by behavioral health clinicians can be easily applied to the treatment of tobacco dependence." This increased to 40.7% at the end of training.

Relations of Current and Past Cancer with Severe Outcomes among 104,590 Hospitalized COVID-19 Patients: The COVID EHR Cohort at the University of Wisconsin.

BACKGROUND: There is mixed evidence about the relations of current versus past cancer with severe COVID-19 outcomes and how they vary by patient and cancer characteristics. METHODS: Electronic health record data of 104,590 adult hospitalized patients with COVID-19 were obtained from 21 United States health systems from February 2020 through September 2021. In-hospital mortality and ICU admission were predicted from current and past cancer diagnoses. Moderation by patient characteristics, vaccination status, cancer type, and year of the pandemic was examined. RESULTS: 6.8% of the patients had current (n = 7,141) and 6.5% had past (n = 6,749) cancer diagnoses. Current cancer predicted both severe outcomes but past cancer did not; adjusted odds ratios (aOR) for mortality were 1.58 [95% confidence interval (CI), 1.46-1.70] and 1.04 (95% CI, 0.96-1.13), respectively. Mortality rates decreased over the pandemic but the incremental risk of current cancer persisted, with the increment being larger among younger vs. older patients. Prior COVID-19 vaccination reduced mortality generally and among those with current cancer (aOR, 0.69; 95% CI, 0.53-0.90). CONCLUSIONS: Current cancer, especially among younger patients, posed a substantially increased risk for death and ICU admission among patients with COVID-19; prior COVID-19 vaccination mitigated the risk associated with current cancer. Past history of cancer was not associated with higher risks for severe COVID-19 outcomes for most cancer types. IMPACT: This study clarifies the characteristics that modify the risk associated with cancer on severe COVID-19 outcomes across the first 20 months of the COVID-19 pandemic. See related commentary by Egan et al., p. 3.

Smoking Status, Nicotine Medication, Vaccination, and COVID-19 Hospital Outcomes: Findings from the COVID EHR Cohort at the University of Wisconsin (CEC-UW) Study.

INTRODUCTION: Available evidence is mixed concerning associations between smoking status and COVID-19 clinical outcomes. Effects of nicotine replacement therapy (NRT) and vaccination status on COVID-19 outcomes in smokers are unknown. METHODS: Electronic health record data from 104 590 COVID-19 patients hospitalized February 1, 2020 to September 30, 2021 in 21 U.S. health systems were analyzed to assess associations of smoking status, in-hospital NRT prescription, and vaccination status with in-hospital death and ICU admission. RESULTS: Current (n = 7764) and never smokers (n = 57 454) did not differ on outcomes after adjustment for age, sex, race, ethnicity, insurance, body mass index, and comorbidities. Former (vs never) smokers (n = 33 101) had higher adjusted odds of death (aOR, 1.11; 95% CI, 1.06-1.17) and ICU admission (aOR, 1.07; 95% CI, 1.04-1.11). Among current smokers, NRT prescription was associated with reduced mortality (aOR, 0.64; 95% CI, 0.50-0.82). Vaccination effects were significantly moderated by smoking status; vaccination was more strongly associated with reduced mortality among current (aOR, 0.29; 95% CI, 0.16-0.66) and former smokers (aOR, 0.47; 95% CI, 0.39-0.57) than for never smokers (aOR, 0.67; 95% CI, 0.57, 0.79). Vaccination was associated with reduced ICU admission more strongly among former (aOR, 0.74; 95% CI, 0.66-0.83) than never smokers (aOR, 0.87; 95% CI, 0.79-0.97). CONCLUSIONS: Former but not current smokers hospitalized with COVID-19 are at higher risk for severe outcomes. SARS-CoV-2 vaccination is associated with better hospital outcomes in COVID-19 patients, especially current and former smokers. NRT during COVID-19 hospitalization may reduce mortality for current smokers. IMPLICATIONS: Prior findings regarding associations between smoking and severe COVID-19 disease outcomes have been inconsistent. This large cohort study suggests potential beneficial effects of nicotine replacement therapy on COVID-19 outcomes in current smokers and outsized benefits of SARS-CoV-2 vaccination in current and former smokers. Such findings may influence clinical practice and prevention efforts and motivate additional research that explores mechanisms for these effects.

Synoptic reporting accuracy for computed tomography pulmonary arteriography among patients suspected of pulmonary embolism.

Background: Structured reporting is an efficient and replicable method of presenting diagnostic results that eliminates variability inherent in narrative descriptive reporting and may improve clinical decisions. Synoptic element reporting can generate discrete coded data that then may inform clinical decision support and trigger downstream actions in computerized electronic health records. Objective: Limited evidence exists for use of synoptic reporting for computed tomography pulmonary arteriography (CTPA) among patients suspected of pulmonary embolism. We reported the accuracy of synoptic reporting for the outcome of pulmonary embolism among patients who presented to an integrated health care system with CTPA performed for suspected pulmonary embolism. Methods: Structured radiology reports with embedded synoptic elements were implemented for all CTPA examinations on March 1, 2018. Four hundred CTPA reports between January 4, 2019 and July 30, 2020 (200 reports each for which synoptic reporting recorded the presence or absence of pulmonary embolism [PE]) were selected at random. One non-diagnostic study was excluded from analysis. We then assessed the accuracy of synoptic reporting compared with the gold standard of manual chart review. Results: Synoptic reporting and manual review agreed in 99.2% of patients undergoing CTPA for suspected PE, agreed on the presence of PE in 196 of 199 (98.5%) cases, the absence of PE in 200 of 200 (100%) cases with a sensitivity of 87.6% (76.1-96.1) a specificity of 99.9% (99.7%-100%), a positive predictive value of 99.5% (98.1-100), and a negative predictive value of 98% (95.7%-99.5%). Conclusion: The overall rate of agreement was 99.2%, but we observed an unacceptable false-negative rate for clinical reliance on synoptic element reporting in isolation from dictated reports.

The first 20 months of the COVID-19 pandemic: Mortality, intubation and ICU rates among 104,590 patients hospitalized at 21 United States health systems.

MAIN OBJECTIVE: There is limited information on how patient outcomes have changed during the COVID-19 pandemic. This study characterizes changes in mortality, intubation, and ICU admission rates during the first 20 months of the pandemic. STUDY DESIGN AND METHODS: University of Wisconsin researchers collected and harmonized electronic health record data from 1.1 million COVID-19 patients across 21 United States health systems from February 2020 through September 2021. The analysis comprised data from 104,590 adult hospitalized COVID-19 patients. Inclusion criteria for the analysis were: (1) age 18 years or older; (2) COVID-19 ICD-10 diagnosis during hospitalization and/or a positive COVID-19 PCR test in a 14-day window (+/- 7 days of hospital admission); and (3) health system contact prior to COVID-19 hospitalization. Outcomes assessed were: (1) mortality (primary), (2) endotracheal intubation, and (3) ICU admission. RESULTS AND SIGNIFICANCE: The 104,590 hospitalized participants had a mean age of 61.7 years and were 50.4% female, 24% Black, and 56.8% White. Overall risk-standardized mortality (adjusted for age, sex, race, ethnicity, body mass index, insurance status and medical comorbidities) declined from 16% of hospitalized COVID-19 patients (95% CI: 16% to 17%) early in the pandemic (February-April 2020) to 9% (CI: 9% to 10%) later (July-September 2021). Among subpopulations, males (vs. females), those on Medicare (vs. those on commercial insurance), the severely obese (vs. normal weight), and those aged 60 and older (vs. younger individuals) had especially high mortality rates both early and late in the pandemic. ICU admission and intubation rates also declined across these 20 months. CONCLUSIONS: Mortality, intubation, and ICU admission rates improved markedly over the first 20 months of the pandemic among adult hospitalized COVID-19 patients although gains varied by subpopulation. These data provide important information on the course of COVID-19 and identify hospitalized patient groups at heightened risk for negative outcomes. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04506528 (https://clinicaltrials.gov/ct2/show/NCT04506528).

CheXED: Comparison of a Deep Learning Model to a Clinical Decision Support System for Pneumonia in the Emergency Department.

PURPOSE: Patients with pneumonia often present to the emergency department (ED) and require prompt diagnosis and treatment. Clinical decision support systems for the diagnosis and management of pneumonia are commonly utilized in EDs to improve patient care. The purpose of this study is to investigate whether a deep learning model for detecting radiographic pneumonia and pleural effusions can improve functionality of a clinical decision support system (CDSS) for pneumonia management (ePNa) operating in 20 EDs. MATERIALS AND METHODS: In this retrospective cohort study, a dataset of 7434 prior chest radiographic studies from 6551 ED patients was used to develop and validate a deep learning model to identify radiographic pneumonia, pleural effusions, and evidence of multilobar pneumonia. Model performance was evaluated against 3 radiologists' adjudicated interpretation and compared with performance of the natural language processing of radiology reports used by ePNa. RESULTS: The deep learning model achieved an area under the receiver operating characteristic curve of 0.833 (95% confidence interval [CI]: 0.795, 0.868) for detecting radiographic pneumonia, 0.939 (95% CI: 0.911, 0.962) for detecting pleural effusions and 0.847 (95% CI: 0.800, 0.890) for identifying multilobar pneumonia. On all 3 tasks, the model achieved higher agreement with the adjudicated radiologist interpretation compared with ePNa. CONCLUSIONS: A deep learning model demonstrated higher agreement with radiologists than the ePNa CDSS in detecting radiographic pneumonia and related findings. Incorporating deep learning models into pneumonia CDSS could enhance diagnostic performance and improve pneumonia management.

The HUD smoke-free rule: Perceptions of residents post-implementation.

In July 2018, the U.S. Department of Housing and Urban Development (HUD) implemented a new Public health Agency rule prohibiting the use of tobacco in and within 25 feet of HUD housing. A convenience sample of 574 residents living in Milwaukee, Wisconsin multi-unit HUD complexes completed a survey from May through July 2019, designed to assess their perceptions of the new policy and its impact. Knowledge of the policy was strong, although continued educational efforts are needed. Attitudes about the policy were generally positive, although smokers held more negative attitudes than non-smokers. Some residents desired more and fairer policy enforcement. Most residents reported that smoke incursions were reduced post policy compared to pre policy, although such incursions still occurred. The policy has had a favorable health impact on smokers; over 80% made at least one positive change in their smoking, including 6.4% who said the policy motivated them to quit. There was no evidence that residents with mobility challenges were differentially affected by the policy. Overall, the HUD smoke-free policy was well received, reduced self-reported exposure to smoke and led most smokers to make positive changes in their smoking. Additional education on the policy, improved enforcement, and cessation services are needed.

Initial Outcomes of a Lung Cancer Screening Program in an Integrated Community Health System.

PURPOSE: Lung cancer screening with low-dose CT (LDCT) demonstrated reduced mortality in the National Lung Screening Trial, yet there is debate as to whether the reported efficacy can translate into comparable effectiveness with community-based screening. The authors' purpose is to report the baseline patient characteristics and malignancy rate in the first 18 months after implementing a lung cancer screening program in an integrated community health system. METHODS: Patients were screened at 1 of 10 participating community-based centers within a 22-hospital system from 2013 to 2015. LDCT examinations were interpreted by 1 of 20 radiologists using structured reporting and an internally developed tracking system. Manual chart review was performed to ascertain the malignancy detection rate. RESULTS: A total of 357 patients were screened with LDCT. Of these, 80 patients were ineligible and 3 declined enrollment. The remaining 274 patients satisfied accepted screening criteria and were enrolled in the program. Malignancy was detected in a total of 11 enrollees (4.0%), 8 with lung cancer and 3 with extrapulmonary primary malignancies. Three patients (1.1%) were diagnosed with early-stage lung cancer and received definitive therapy. CONCLUSIONS: Early-stage lung cancer was detected with LDCT screening in an integrated community health system at a rate similar to other trials.

Follow-up of Incidental Pulmonary Nodules and the Radiology Report.

PURPOSE: Incidental pulmonary nodules that require follow-up are often noted on chest CT. Evidence-based guidelines regarding appropriate follow-up have been published, but the rate of adherence to guideline recommendations is unknown. Furthermore, it is unknown whether the radiology report affects the nodule follow-up rate. METHODS: A review of 1,000 CT pulmonary angiographic studies ordered in the emergency department was performed to determine the presence of an incidental pulmonary nodule. Fleischner Society guidelines were applied to ascertain if follow-up was recommended. Radiology reports were classified on the basis of whether nodules were listed in the findings section only, were noted in the impression section, or had explicit recommendations for follow-up. Whether the rate of nodule follow-up was affected by the radiology report was determined according to these 3 groups. RESULTS: Incidental pulmonary nodules that required follow-up were noted on 9.9% (95% confidence interval, 8%-12%) of CT pulmonary angiographic studies. Follow-up for nodules was poor overall (29% [28 of 96]; 95% confidence interval, 20%-38%) and decreased significantly when the nodules were mentioned in the findings section only (0% [0 of 12]). Specific instructions to follow up nodules in radiology reports still resulted in a low follow-up rate of 29% (19 of 65; 95% confidence interval, 18%-40%). CONCLUSIONS: Incidental pulmonary nodules detected on CT pulmonary angiography are common and are frequently not followed up appropriately. Although the inclusion of a pulmonary nodule in the impression section of a radiology report is helpful, it does not ensure follow-up. Better systems for appropriate identification and follow-up of incidental findings are needed.

Cleared for takeoff: The effects of hypobaric conditions on traumatic pneumothoraces.

BACKGROUND: Current guidelines suggest that traumatic pneumothorax (tPTX) is a contraindication to commercial airline travel, and patients should wait at least 2 weeks after radiographic resolution of tPTX to fly. This recommendation is not based on prospective, physiologic study. We hypothesized that despite having a radiographic increase in pneumothorax size while at simulated altitude, patients with a recently treated tPTX would not exhibit any adverse physiologic changes and would not report any symptoms of cardiorespiratory compromise. METHODS: This is a prospective, observational study of 20 patients (10 in Phase 1, 10 in Phase 2) with tPTX that has been treated by chest tube (CT) or high flow oxygen therapy. CT must have been removed within 48 hours of entering the study. Subjects were exposed to 2 hours of hypobaria (554 mm Hg in Phase 1, 471 mm Hg in Phase 2) in a chamber in Salt Lake City, Utah. Vital signs and subjective symptoms were recorded during the "flight." After 2 hours, while still at simulated altitude, a portable chest radiograph (CXR) was obtained. tPTX sizes on preflight, inflight, and postflight CXR were compared. RESULTS: Sixteen subjects (80%) were male. Mean (SD) age and ISS were 49 (5) years and 10.5 (4.6), respectively. Fourteen (70%) had a CT to treat tPTX, which had been removed 19 hours (range, 4-43 hours) before the study. No subject complained of any cardiorespiratory symptoms while at altitude. Radiographic increase in tPTX size at altitude was 5.6 (0.61) mm from preflight CXR. No subject developed a tension tPTX. No subject required procedural intervention during the flight. Four hours after the study, all tPTX had returned to baseline size. CONCLUSION: Patients with recently treated tPTX have a small increase in the size of tPTX when subjected to simulated altitude. This is clinically well tolerated. Current prohibitions regarding air travel following traumatic tPTX should be reconsidered and further studied. LEVEL OF EVIDENCE: Therapeutic study, level IV.

Follow-up of incidental pulmonary nodules and the radiology report.

PURPOSE: Incidental pulmonary nodules that require follow-up are often noted on chest CT. Evidence-based guidelines regarding appropriate follow-up have been published, but the rate of adherence to guideline recommendations is unknown. Furthermore, it is unknown whether the radiology report affects the nodule follow-up rate. METHODS: A review of 1,000 CT pulmonary angiographic studies ordered in the emergency department was performed to determine the presence of an incidental pulmonary nodule. Fleischner Society guidelines were applied to ascertain if follow-up was recommended. Radiology reports were classified on the basis of whether nodules were listed in the findings section only, were noted in the impression section, or had explicit recommendations for follow-up. Whether the rate of nodule follow-up was affected by the radiology report was determined according to these 3 groups. RESULTS: Incidental pulmonary nodules that required follow-up were noted on 9.9% (95% confidence interval, 8%-12%) of CT pulmonary angiographic studies. Follow-up for nodules was poor overall (29% [28 of 96]; 95% confidence interval, 20%-38%) and decreased significantly when the nodules were mentioned in the findings section only (0% [0 of 12]). Specific instructions to follow up nodules in radiology reports still resulted in a low follow-up rate of 29% (19 of 65; 95% confidence interval, 18%-40%). CONCLUSIONS: Incidental pulmonary nodules detected on CT pulmonary angiography are common and are frequently not followed up appropriately. Although the inclusion of a pulmonary nodule in the impression section of a radiology report is helpful, it does not ensure follow-up. Better systems for appropriate identification and follow-up of incidental findings are needed.

Adherence to PIOPED II investigators' recommendations for computed tomography pulmonary angiography.

BACKGROUND: Computed tomography (CT) pulmonary angiography use has increased dramatically, raising concerns for patient safety. Adherence to recommendations and guidelines may protect patients. We measured adherence to the recommendations of Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED II) investigators for evaluation of suspected pulmonary embolism and the rate of potential false-positive pulmonary embolism diagnoses when recommendations of PIOPED II investigators were not followed. METHODS: We used a structured record review to identify 3500 consecutive CT pulmonary angiograms performed to investigate suspected pulmonary embolism in 2 urban emergency departments, calculating the revised Geneva score (RGS) to classify patients as "pulmonary embolism unlikely" (RGS≤10) or "pulmonary embolism likely" (RGS>10). CT pulmonary angiograms were concordant with PIOPED II investigator recommendations if pulmonary embolism was likely or pulmonary embolism was unlikely and a highly sensitive D-dimer test result was positive. We independently reviewed 482 CT pulmonary angiograms to measure the rate of potential false-positive pulmonary embolism diagnoses. RESULTS: A total of 1592 of 3500 CT pulmonary angiograms (45.5%) followed the recommendations of PIOPED II investigators. The remaining 1908 CT pulmonary angiograms were performed on patients with an RGS≤10 without a D-dimer test (n=1588) or after a negative D-dimer test result (n=320). The overall rate of pulmonary embolism was 9.7%. Potential false-positive diagnoses of pulmonary embolism occurred in 2 of 3 patients with an RGS≤10 and a negative D-dimer test result. CONCLUSIONS: Nonadherence to recommendations for CT pulmonary angiography is common and exposes patients to increased risks, including potential false-positive diagnoses of pulmonary embolism.

Radiation and chest CT scan examinations: what do we know?

In the past 3 decades, the total number of CT scans performed has grown exponentially. In 2007, > 70 million CT scans were performed in the United States. CT scan studies of the chest comprise a large portion of the CT scans performed today because the technology has transformed the management of common chest diseases, including pulmonary embolism and coronary artery disease. As the number of studies performed yearly increases, a growing fraction of the population is exposed to low-dose ionizing radiation from CT scan. Data extrapolated from atomic bomb survivors and other populations exposed to low-dose ionizing radiation suggest that CT scan-associated radiation may increase an individual's lifetime risk of developing cancer. This finding, however, is not incontrovertible. Because this topic has recently attracted the attention of both the scientific community and the general public, it has become increasingly important for physicians to understand the cancer risk associated with CT scan and be capable of engaging in productive dialogue with patients. This article reviews the current literature on the public health debate surrounding CT scan and cancer risk, quantifies radiation doses associated with specific studies, and describes efforts to reduce population-wide CT scan-associated radiation exposure. CT scan examinations of the chest, including CT scan pulmonary and coronary angiography, high-resolution CT scan, low-dose lung cancer screening, and triple rule-out CT scan, are specifically considered.