The safety of performing diagnostic cardiac catheterizations in a mobile catheterization laboratory at primary care hospitals

Evidence for models of diagnostic service provision in the community: literature mapping exercise and focused rapid reviews

Background

Current NHS policy favours the expansion of diagnostic testing services in community and primary care settings.

Objectives

Our objectives were to identify current models of community diagnostic services in the UK and internationally and to assess the evidence for quality, safety and clinical effectiveness of such services. We were also interested in whether or not there is any evidence to support a broader range of diagnostic tests being provided in the community.

Review methods

We performed an initial broad literature mapping exercise to assess the quantity and nature of the published research evidence. The results were used to inform selection of three areas for investigation in more detail. We chose to perform focused reviews on logistics of diagnostic modalities in primary care (because the relevant issues differ widely between different types of test); diagnostic ultrasound (a key diagnostic technology affected by developments in equipment); and a diagnostic pathway (assessment of breathlessness) typically delivered wholly or partly in primary care/community settings. Databases and other sources searched, and search dates, were decided individually for each review. Quantitative and qualitative systematic reviews and primary studies of any design were eligible for inclusion.

Results

We identified seven main models of service that are delivered in primary care/community settings and in most cases with the possible involvement of community/primary care staff. Not all of these models are relevant to all types of diagnostic test. Overall, the evidence base for community- and primary care-based diagnostic services was limited, with very few controlled studies comparing different models of service. We found evidence from different settings that these services can reduce referrals to secondary care and allow more patients to be managed in primary care, but the quality of the research was generally poor. Evidence on the quality (including diagnostic accuracy and appropriateness of test ordering) and safety of such services was mixed.

Conclusions

In the absence of clear evidence of superior clinical effectiveness and cost-effectiveness, the expansion of community-based services appears to be driven by other factors. These include policies to encourage moving services out of hospitals; the promise of reduced waiting times for diagnosis; the availability of a wider range of suitable tests and/or cheaper, more user-friendly equipment; and the ability of commercial providers to bid for NHS contracts. However, service development also faces a number of barriers, including issues related to staffing, training, governance and quality control.

Limitations

We have not attempted to cover all types of diagnostic technology in equal depth. Time and staff resources constrained our ability to carry out review processes in duplicate. Research in this field is limited by the difficulty of obtaining, from publicly available sources, up-to-date information about what models of service are commissioned, where and from which providers.

Future work

There is a need for research to compare the outcomes of different service models using robust study designs. Comparisons of ‘true’ community-based services with secondary care-based open-access services and rapid access clinics would be particularly valuable. There are specific needs for economic evaluations and for studies that incorporate effects on the wider health system. There appears to be no easy way of identifying what services are being commissioned from whom and keeping up with local evaluations of new services, suggesting a need to improve the availability of information in this area.

Funding

The National Institute for Health Research Health Services and Delivery Research programme.

Helicopter EMS: Research Endpoints and Potential Benefits

Patients, EMS systems, and healthcare regions benefit from Helicopter EMS (HEMS) utilization. This article discusses these benefits in terms of specific endpoints utilized in research projects. The endpoint of interest, be it primary, secondary, or surrogate, is important to understand in the deployment of HEMS resources or in planning further HEMS outcomes research. The most important outcomes are those which show potential benefits to the patients, such as functional survival, pain relief, and earlier ALS care. Case reports are also important "outcomes" publications. The benefits of HEMS in the rural setting is the ability to provide timely access to Level I or Level II trauma centers and in nontrauma, interfacility transport of cardiac, stroke, and even sepsis patients. Many HEMS crews have pharmacologic and procedural capabilities that bring a different level of care to a trauma scene or small referring hospital, especially in the rural setting. Regional healthcare and EMS system's benefit from HEMS by their capability to extend the advanced level of care throughout a region, provide a "backup" for areas with limited ALS coverage, minimize transport times, make available direct transport to specialized centers, and offer flexibility of transport in overloaded hospital systems.

Mobile cardiac catheterization laboratories increase use of cardiac care in women and African Americans

BACKGROUND

Women and minorities traditionally have shown less use of diagnostic cardiac catheterization. We sought to determine whether mobile cardiac catheterization laboratories may increase the use of catheterization among women and minorities by bringing the technology to remote communities.

METHODS

We collected data on consecutive patients undergoing cardiac catheterization at mobile laboratories located at 15 community hospitals in North Carolina and Virginia from 1994 to 2005. These data were compared with those from similar consecutive outpatients at the Duke University Medical Center (Durham, NC) cardiac catheterization laboratory over the same period. Logistic regression modeling techniques were used to determine which patient factors were associated with the decision to use a particular facility.

RESULTS

Women comprised 48% of the patients undergoing cardiac catheterization via mobile laboratory versus 42% of those patients receiving outpatient catheterization at the medical center laboratory (P < .001). All racial minorities combined (African American, Hispanic, Native American, Asian, and other) made up 27% of the mobile laboratory population undergoing catheterization versus 21% of the medical center outpatients who underwent the procedure (P < .001). Most minorities were African American. The most important predictor of patients receiving catheterization via a mobile laboratory rather than at the medical center catheterization laboratory was distance to the nearest mobile facility. Within a home-to-mobile laboratory range of approximately 35 miles, the odds of being treated at a mobile laboratory increased greatly the closer the patient lived to the facility.

CONCLUSIONS

The strongest predictor of mobile laboratory use was the patient's proximity to the mobile facility. When compared with a traditional tertiary referral outpatient hospital setting, a greater percentage of women and African Americans received cardiac catheterization at mobile laboratories. The availability of mobile laboratories may increase the use of cardiac procedures among women and African Americans.