Brief ReportImaging in the NEXUS-negative patient: when we break the rule☆
Introduction
Clinical decision rules (CDRs) are evidence based guidelines utilized by physicians to make informed decisions on when to use certain diagnostic tests and therapies while caring for patients. The NEXUS (National Emergency X-Radiography Utilization Study) cervical spine criteria are an example of one such rule that is widely used in US emergency departments (EDs), which stem from research completed in a large prospective observational study. The study, published in 2000, investigated the historically liberal use of cervical spine radiological imaging by clinicians in low risk blunt trauma patients [1]. In summary, the criteria only recommend cervical spine imaging in patients who have one or more of the following after injury: posterior midline cervical tenderness, evidence of intoxication, a focal neurological deficit, a clinically apparent painful distracting injury and decreased level of alertness. The Canadian C-spine rule (CCR) is another CDR that has been widely studied in the clearance of the cervical spine after blunt trauma [2]. The CCR is widely endorsed in Canada [3] and is viewed as an alternative triage criteria to NEXUS by the Bone and Joint Decade 2000-2010 Task Force on Neck Pain and its Associated Disorders [4]. Although there is much debate as to which rule is more accurate [5], the CCR has been reported to be relatively difficult to remember and apply as compared to other CDRs [3], [6]. A small study of US emergency physicians demonstrated increased comfort with and application of NEXUS as compared to the CCR [6]. Therefore, we chose to study application of NEXUS low-risk criteria, which is the historically preferred CDR in cervical spine clearance in our US emergency department (ED), although we acknowledge that it is unclear if it is the better rule.
The NEXUS criteria have been validated in multiple studies [7], [8], including their application to pediatric and geriatric patients [9], [10]; however, few studies have investigated their actual application in clinical practice. CDRs which have been validated often have significant barriers to their implementation [11], and anecdotally, NEXUS-negative patients are often imaged in clinical practice in spite of extensive criteria validation. To our knowledge, only one recent study has evaluated the actual use of the NEXUS rules by emergency physicians in the United States, and this study demonstrated that neither NEXUS nor the CCR were being applied well or consistently by the enrolled physicians [6]. Patient insistence to obtain imaging was the number one reason cited by physicians who did not follow the NEXUS low risk criteria, while difficulty remembering the rule was the most commonly cited reason for not using the CCR [6]. Additionally, the research found the second most common reason for digression from NEXUS was physician fear of possible medicolegal ramifications if imaging was not obtained. This study pointed out a number of clinicians who were inexperienced in using this decision rule or had difficulty remembering the criteria.
Although most academic emergency physicians and residents are aware of the NEXUS C-spine rule, our goal was to determine the prevalence of these emergency medicine (EM) providers’ adherence to the NEXUS criteria in a prospective approach. We sought to determine which patient-related variables (age, mechanism of injury) and which provider-related variables (provider level of training, provider self-reported motivation) contribute to the decision of EM residents and faculty to image patients who meet all NEXUS low-risk criteria after blunt trauma in one US ED.
Section snippets
Study design
This study was a prospective observational study of the application of NEXUS low-risk cervical spine clearance criteria by EM residents and attending physicians. The study was reviewed and approved by the hospital’s institutional review board.
Study setting and population
The study was performed at a 75,000 volume community Level 1 trauma center that hosts an EM residency training program with 40 total residents. Resident and attending physicians were educated regarding the study during mandatory education time (at weekly
Results
Three hundred patients were enrolled over an 11-month period from November 2011 to September 2012. The mean age of patients was 71 years (SD ± 22 years); 183 (61%) were women and 117 (39%) were men; 296 (99%) of patients were adults and 4 (1%) of those enrolled were children under the age of 18; 79% of patients enrolled were being evaluated after a fall; which was usually from a standing position. The remainder included 16% from motor vehicle collisions, 3% after being assaulted and 2% having
Discussion
In our cohort, the digression from applying NEXUS in this population led to the diagnosis of two injuries which would otherwise have been missed. These two injuries were in elderly patients who were ultimately managed conservatively.
After reviewing the medical record of the NEXUS negative patient suffering multiple fractures of C4, the initial clinician stated the patient was alert and oriented however a note on the chart by the attending physician reported the patient as “altered and
Limitations
Our study is limited by lack of formal follow up with patients regarding those who did not have cervical spine imaging in the ED. Although this calls into question the designation of clinically relevant injuries, we did not set out to validate the NEXUS criteria. A re-evaluation of the sensitivity and specificity of NEXUS would take thousands of patients. Granting we enrolled 300 patients and had 2 positive findings on imaging of NEXUS negative patients, 121 others were NEXUS negative and
Conclusion
Regardless of level of training, providers in our ED adhere to NEXUS criteria approximately 80% of the time. Advanced patient age, fall mechanism, and patient’s requirement for head CT led to use of cervical imaging in a significant number of NEXUS negative patients. Two of these had clinically relevant injuries which were managed conservatively. Further research is warranted regarding clinical clearance of the cervical spine in elderly fall patients who are at higher risk for injury and in
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Cited by (26)
Disproportionate Use in Minor Trauma Is Driving Emergency Department Cervical Spine Imaging: An Injury Severity Score–Based Analysis
2021, Journal of the American College of RadiologyCitation Excerpt :To reduce inappropriate ED cervical spine imaging as well as variation in practice, clinical prediction rules such as the National Emergency X-Radiography Utilization Study and the Canadian C-spine Rule were established two decades ago [4,5]. Although both tools have been well validated [6,7], their impact on physician ordering behavior has been mixed [8,9], and neither considers the contemporaneous role of CT [10,11]. It is currently unclear whether previously reported changing national patterns of ED cervical spine imaging in Medicare beneficiaries are generalizable to non-Medicare populations and uniformly distributed across the country.
A prospective evaluation of cervical spine immobilisation in low-risk trauma patients at a tertiary Emergency Department
2019, Australasian Emergency CareCitation Excerpt :Similar studies reporting on various approaches to CSI have also shown practice variation and non-adherence to guidelines [19]. Morrison et al. [19] conducted a prospective observational study of low-risk ED trauma patients. In their study, 53/169 patients who received spinal imaging met the locally agreed criteria for early CSI clearance.
Routine pelvic X-rays in asymptomatic hemodynamically stable blunt trauma patients: A meta-analysis
2018, InjuryCitation Excerpt :Recent studies suggested that in certain patients (pelvic) X-rays may be ordered as targeted tests instead of being performed routinely [2,3]. However, as opposed to the generally accepted national emergency x-radiography utilization study (NEXUS) criteria and the Ottawa ankle and knee rules, which limit unnecessary radiological imaging in trauma patients [4,5], no such consensus exists for avoiding unnecessary pelvic X-rays in trauma patients. Furthermore, a retrospective study found that most avoidable costs made during standard trauma work up were due to radiology and laboratory panels [3].
Head and Neck Injuries: Special Considerations in the Elderly Patient
2018, Neuroimaging Clinics of North AmericaCitation Excerpt :Some reports suggest that NEXUS is adequate for screening for significant cervical spine fractures in elderly patients,36,48 including those at a baseline decreased GCS and those with distracting injuries not related to the head and neck region.49 However, NEXUS has been criticized by others for having lower sensitivity for detection of cervical spine injuries in geriatric trauma patients.50–52 Accurate diagnosis of cervical spine injuries may be more difficult in elderly patients as well.34
Over the hill and falling down: Can the NEXUS criteria be applied to the elderly?
2018, International Journal of SurgeryCitation Excerpt :Several smaller studies have also warned against the use of the NEXUS criteria with missed injuries in NEXUS-negative patients [3,6,12]. One study reported two missed injuries in a cohort of 51 elderly patients.[6] A follow up to the original NEXUS study, however, reported 100% sensitivity in the NEXUS dataset in detecting clinically significant cervical spine injuries in 2943 elderly patients.
Cost-effectiveness of Magnetic Resonance Imaging in Cervical Spine Clearance of Neurologically Intact Patients With Blunt Trauma
2018, Annals of Emergency Medicine
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Presentations: American College of Emergency Medicine Denver, CO, October 2012; Society of Academic Emergency Medicine Atlanta, GA, May 2013.