Mathew Mercuri

Predictors of increased radiation dose during percutaneous coronary intervention.

Radiation-induced injury is a potential unintended outcome of fluoroscopy-supported cardiology procedures (e.g., percutaneous coronary intervention [PCI]). The injury might be deterministic in nature. Air kerma (AK) is considered an indicator of skin dose, and thus, an indicator for deterministic effects. Few studies have investigated the factors that contribute to an increased radiation dose, and none have used AK as a dependent variable. We studied the registry data of 967 consecutive patients (derivation model) undergoing ad hoc PCI. Linear and multiple regression analyses were performed to investigate which clinical, technical, and anatomic factors were associated with an increased AK. Multiple regression analyses were performed on an additional sample of 1,082 consecutive patients (validation model) to confirm the results. The variables found significant (multiple regression analyses) were radial access (mean increase in AK 253 mGy, 95% confidence interval [CI] 104 to 418, p = 0.0006), number of lesions treated (547 mGy, 95% CI 332 to 789, p < 0.0001), Type C lesions (132 mGy, 95% CI, 26 to 246, p = 0.014), bifurcation lesions (280 mGy, 95% CI 104 to 477, p = 0.0013), and chronic total occlusions (453 mGy, 95% CI 76 to 923, p = 0.016). The validation model (n = 1,082) confirmed all but type C lesions (p = 0.065). In conclusion, the present study has described factors that might contribute to an increased AK during PCI. In revealing a priori known factors associated with an increased radiation dose during PCI, physicians and patients might be more able to evaluate the risks and benefits of such a procedure.

When guidelines don't guide: the effect of patient context on management decisions based on clinical practice guidelines.

Purpose This study examines the influence of patient social context on physicians’ adherence to clinical practice guidelines (CPGs). Method Expert emergency medicine (EM) physicians and novice physicians (EM residents) were surveyed using an Internet-based program between January and July of 2013. Participants were presented clinical cases and were asked to indicate if they would order or prescribe a specified test or treatment. Cases were chosen from four domains where CPGs exist, and were constructed to include or exclude a “context variable” (CV). Both expert and novice physicians’ CPG adherence rate in the CV condition was compared with that in the no CV condition. The CPG adherence rates in CV and no CV conditions were also compared between expert and novice EM physicians. Results Expert EM physicians (n = 28) were less likely to adhere to CPGs in the CV condition compared with the no CV condition (56% versus 80%, respectively; odds ratio [OR] = 0.32, 95% confidence interval [CI]: 0.17–0.53, P < .001). Experts were less likely to adhere to CPGs in the CV condition when compared with novice physicians (n = 28) (56% versus 67%; OR = 0.62, 95% CI: 0.39–1.0, P = .039). Expert and novice EM physicians did not differ in their adherence to CPGs in the no CV condition. Conclusions Participants were sensitive to both the best clinical evidence of benefit, as recommended by CPGs, and patient context when determining how care should be managed.

Tracking patient radiation exposure: Challenges to integrating nuclear medicine with other modalities

The cumulative radiation exposure to the patient from multiple radiological procedures can place some individuals at significantly increased risk for stochastic effects and tissue reactions. Approaches, such as those in the International Atomic Energy Agency’s Smart Card program, have been developed to track cumulative radiation exposures to individuals. These strategies often rely on the availability of structured dose reports, typically found in the DICOM header. Dosimetry information is currently readily available for many individual x-ray-based procedures. Nuclear medicine, of which nuclear cardiology constitutes the majority of the radiation burden in the US, currently lags behind x-ray-based procedures with respect to reporting of radiation dosimetric information. This article discusses qualitative differences between nuclear medicine and x-ray-based procedures, including differences in the radiation source and measurement of its strength, the impact of biokinetics on dosimetry, and the capability of current scanners to record dosimetry information. These differences create challenges in applying, monitoring, and reporting strategies used in x-ray-based procedures to nuclear medicine, and integrating dosimetry information across modalities. A concerted effort by the medical imaging community, dosimetry specialists, and manufacturers of imaging equipment is required to develop strategies to improve the reporting of radiation dosimetry data in nuclear medicine. Some ideas on how to address this issue are suggested.

Adherence to Standards for Reporting Diagnostic Accuracy in Emergency Medicine Research

BACKGROUND Diagnostic tests are used frequently in the emergency department (ED) to guide clinical decision making and, hence, influence clinical outcomes. The Standards for Reporting of Diagnostic Accuracy (STARD) criteria were developed to ensure that diagnostic test studies are performed and reported to best inform clinical decision making in the ED. OBJECTIVE The objective was to determine the extent to which diagnostic studies published in emergency medicine journals adhered to STARD 2003 criteria. METHODS Diagnostic studies published in eight MEDLINE-listed, peer-reviewed, emergency medicine journals over a 5-year period were reviewed for compliance to STARD criteria. RESULTS A total of 12,649 articles were screened and 114 studies were included in our study. Twenty percent of these were randomly selected for assessment using STARD 2003 criteria. Adherence to STARD 2003 reporting standards for each criteria ranged from 8.7% adherence (criteria-reporting adverse events from performing index test or reference standard) to 100% (multiple criteria). CONCLUSION Just over half of STARD criteria are reported in more than 80% studies. As poorly reported studies may negatively impact their clinical usefulness, it is essential that studies of diagnostic test accuracy be performed and reported adequately. Future studies should assess whether studies have improved compliance with the STARD 2015 criteria amendment.

Radiation exposure from medical imaging: a silent harm?

Advances in medical imaging have had a considerable impact on medical practice over the past few decades. Regrettably, many such procedures expose patients to ionizing radiation, which may result in injury. Survey data show that physicians generally underestimate the magnitude of radiation doses and

Treatment assignment of high-risk symptomatic severe aortic stenosis patients referred for transcatheter AorticValve implantation.

Transcatheter aortic valve implantation (TAVI) has become an option for patients with symptomatic severe aortic stenosis whose co-morbidities place them at high surgical risk. However, little is known regarding treatment allocation. From May 2008 to May 2011, all high-risk patients with symptomatic severe aortic stenosis referred to an experienced single-center TAVI clinic were reviewed. A total of 170 consecutive patients were evaluated. Of these, 58 (34%) were accepted for TAVI (mean age 81 ± 8 years). Thirty-three patients (19%) were accepted for conventional aortic valve replacement (AVR; mean age 83 ± 6 years). Sixty-two patients (37%) were treated conservatively (mean age 83 ± 6 years). Seventeen patients (10%) died awaiting complete assessment. At 30 days, all-cause mortality was 10% in the TAVI group, 3% in the conventional AVR group, and 32% in the conservatively treated group. Multivariate-adjustment identified the absence of chronic obstructive pulmonary disease (hazard ratio 0.30, 95% confidence interval 0.09 to 0.98, p <0.05) and the absence of frailty (hazard ratio 0.19, 95% confidence interval 0.07 to 0.55, p <0.01) as independent predictors of conventional AVR. In conclusion, of the high-risk patients with severe aortic stenosis referred for TAVI at a large single center, approximately 1/2 were accepted for intervention (conventional AVR or TAVI), and roughly 1/3 were treated conservatively.

The evolution of GRADE (part 1): Is there a theoretical and/or empirical basis for the GRADE framework?

RATIONALE, AIMS, AND OBJECTIVES The Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) framework has been presented as the best method available for developing clinical recommendations. GRADE has undergone a series of modifications. Here, we present the first part of a three article series examining the evolution of GRADE. Our purpose is to explore if (and if so, how) GRADE provides: (1) a justification (ie, theoretical and/or empirical) for why the criteria/components under consideration in the system are included (and other factors excluded), as well as why some criteria/components where added/modified in the evolution process, (2) clear and functional (ie, how to operationalize them) definitions of the included criteria/components, and (3) instruction and justification for how all the criteria/components are to be integrated when determining a recommendation. In part 1 of the series, we examine the first two versions of GRADE. METHODS Narrative review. RESULTS The justification scheme that sustains GRADE is not articulated in the first two versions of the framework. Why some criteria/components were included, and others excluded, is not justified theoretically nor is empirical support provided to suggest that the framework as presented includes that which is needed to produce valid recommendations. The first two versions of GRADE show a lack of clear instruction on how to operationalize the criteria for assessing the quality of evidence and the components for making a recommendation (including how to integrate the criteria/components at each step), which leaves substantial room for judgement on the part of the user of GRADE for guideline development. CONCLUSIONS This article revealed an absence of a justification (theoretical and/or empirical) to support important aspects of the GRADE framework, as well as a lack of clear instruction on how to operationalize the criteria and components in the framework. These issues limit ones ability to scientifically assess the appropriateness of GRADE for determining clinical recommendations.

Building Capacity in Healthcare by Re-examining Clinical Services in Paramedicine

ABSTRACT Objectives: Emergency departments (ED) continue to be overburdened, leading to crowding and elevated risk of negative clinical outcomes. Extending clinical services to paramedics may support efforts to improve ED burdens by promoting health care access and capacity during times of patient crisis. The objective of this study was to identify the clinical course and most responsible diagnosis of patients transported by paramedic services to local EDs to then evaluate impact of various augmented 9-1-1/paramedic clinical service models on the need for additional ED services. Methods: A retrospective cohort and model-simulation based study. We retrieved clinical data from hospital records for a random selection of 3,000 patients who engaged 9-1-1/paramedic services and were transported to a regional ED to identify their clinical course (interventions, diagnostics) disposition and most responsible admitting/discharge diagnosis. We used this data to establish, simulate and test numerous paramedic service models on the need for ED services. Results: A random selection of 3,000 patients was reviewed across 3 hospitals. The majority were female (57.2%) with a mean age of 65 (SD = 21.3). The majority (n = 1954; 65.1%) were discharged directly from ED of which 3.6% (n = 108) received no intervention or diagnostic, 20.4% (n = 611) received only a diagnostic, 4.8% (n = 143) received only an intervention and 36.4% (n = 1092) received both an intervention and diagnostic. The proportion of nonadmitted patients rose to 82.2% and 77.2% when considering lower priority patients and age greater than 65, respectively. Patient types were identified based on frequency and association with discharge directly from ED. Twelve simulated augmented paramedic clinical service models are reported with estimated gains in the number of patients who may no longer require ED services ranging from 7.5% (n = 146) to 35.4% (n = 691). Conclusions: This study suggests a reduction in need for ED services may be achieved through innovative models of paramedic services at the time of crisis. Identifying and confirming patient types/events to target and clinical services to include in the model requires ongoing investigation. Future research will be needed to evaluate the accuracy and impact of the models presented. Keywords: Paramedic; EMS; Community Paramedicine; Healthcare Service Delivery; ED Crowding; primary care

The evolution of GRADE (part 2): Still searching for a theoretical and/or empirical basis for the GRADE framework

RATIONALE, AIMS, AND OBJECTIVES The GRADE framework has been widely adopted as the preferred method for developing clinical practice recommendations. In the first article of our three part series examining the evolution of GRADE, we showed an absence (in the first two versions of GRADE) of a theoretical basis and/or empirical data to support why the presented criteria for determining the quality of evidence regarding the effect estimate and the components under consideration for determining the strength of the recommendation were included and other criteria/components excluded. Furthermore, often, it was not clear how to operationalize the included criteria/components (and integrate them) when using the framework. In part 2 of this series, we examine if version 3 of GRADE offered improvements on previous versions with respect to a justification scheme and how to operationalize the frameworks criteria/components. METHODS Narrative review. RESULTS Our examination suggests that version 3 has done little to improve on the justification scheme that sustains GRADE. Still absent is a justification (theoretical and/or empirical) for why the criteria/components were chosen. Likewise, version 3 is still lacking clarity regarding how to implement and integrate the criteria/considerations in the framework (ie, operationalize the framework) when determining the quality of evidence or strength of recommendation. Transparency is now emphasized as the merit of GRADE. However, we are offered no theoretical justification for how the use of GRADE should achieve transparency or empirical evidence to support that transparency is achieved. CONCLUSIONS While version 3 reveals acknowledgement by the authors of GRADE that the framework is a work in progress, it still lacks a justification scheme (theoretical and/or empirical) to sustain it and clarity in its criteria/components to operationalize it. As was suggested in part 1, such issues limit ones ability to scientifically assess the appropriateness of GRADE for its stated purpose.

Examining the role of the physician as a source of variation: Are physician‐related variations necessarily unwarranted?

RATIONALE, AIMS, AND OBJECTIVES The physician is often implicated as an important cause of observed variations in health care service use. However, it is not clear if physician-related variation is problematic for patient care. This paper illustrates that observed physician-related variation is not necessarily unwarranted. METHODS This is a narrative review. RESULTS Many studies have attributed observed variations to the physician, but little attention is given towards discriminating between those variations that exist for good reasons and those that are unwarranted. Two arguments can be made for why physician-related variation is unwarranted. The first posits that physician-related factors should not play a role in management of care decisions because such decisions should be driven by science (which is imagined to be definitive). The second considers the possibility of supplier-induced demand as a factor driving observed variations. We show that neither argument is sufficient to rule out that physician-related variations may be warranted. Furthermore, the claim that such variations are necessarily problematic for patients has yet to be substantiated empirically. CONCLUSIONS It is not enough to simply show that physician-related variation can exist-one must also show where it is unwarranted and what is the magnitude of unwarranted variations. Failure to show this can have significant implications on how we interpret and respond to observed variations. Improved measurement of the sources of variation, especially with respect to patient preferences and context, may help us start to disentangle physician-related variation that is desirable from that which is unwarranted.