Analysis of Radiation Exposure in Trauma Patients at a Level I Trauma Center

Pan scan for geriatric trauma patients: Overkill or necessary?

BACKGROUND

Geriatric patients manifest pain and physical findings differently and are associated with higher mortality and complications. We hypothesized that physical exam (PE) is unreliable versus computed tomography (CT) for comprehensive injury identification in geriatric patients. Additionally, we quantified significant incidental radiologic findings.

STUDY DESIGN

Our institution adopted a policy of Pan Scan (PS) CT for trauma activations of patients ≥65 years. PS included CT of head/neck and chest/abdomen/pelvis. PE and imaging findings were extracted from physician reports.

RESULTS

50 ​% of patients had clinically significant CT traumatic findings. Of these, 75 ​% had PE correlating to significant CT findings, while 25 ​% had significant PS findings not identifiable on PE (p ​< ​0.001). The NPV was 0.80 for the PE. 57.7 ​% had clinically significant incidental findings.

CONCLUSION

Physical exam alone is not sensitive enough to detect all traumatic injuries in elderly patients. As an added benefit to PS, important incidental findings are identified. These data support use of PS in geriatric trauma to optimize care.

Pelvic radiation dose measurement for trauma patients in multifield radiographic examinations: A phantom-based TLD dosimetry study

BACKGROUND AND AIMS

Trauma patients often suffer from multiple injuries and require undergoing various radiography which is referred to as multifield radiographic examinations. Protective measures may be ignored for these examinations due to stressful emergency situations or patients' conditions. This study was conducted to evaluate the scattered doses received by the pelvis during different common multifield radiographic examinations with an emphasis on field size adjustment.

METHODS

A whole-body phantom, PBU-50, resembling the body mass, was used to carry out the common examinations for trauma patients (extremities, skull, chest, abdomen, pelvis, femur, and lumbar radiography), using a Pars Pad X-ray machine. To measure the primary entrance skin doses, three calibrated GR 200 thermoluminescence dosimeter (TLD) chips were placed in the central X-ray beam of scanned organs. Three TLDs were also placed on the pelvis symphysis pubis to measure the scattered dose received by the pelvis due to each carried-out radiography for standard and clinically used field sizes. A Harshaw 3500 TLD Reader was used to read the chips. TLD readouts (nano-Coulomb) were converted to dose (milli Gray [mGy]) using the predefined calibration curve.

RESULTS

The scattered doses to the pelvis due to scanning a single organ differed from 0.80 to 1.70, and 0.82 to 4.09 mGy for standard and clinically used field sizes, respectively. The scattered doses to the pelvis in multifield examinations varied from 0.80 to 8.43 and 0.82 to 13.6 mGy for standard and clinically used field sizes, respectively, depending on the number of scanned organs and their distances from the pelvis.

CONCLUSIONS

Multiple and repeated radiographs combined with insufficient protective measures can increase the patient's dose. The findings indicate that the scattered doses received by the pelvis can exceed the reference values in multifield radiography, especially if the radiation field is not restricted properly to the scanned organ.

Imaging of penetrating vascular trauma of the body and extremities secondary to ballistic and stab wounds

In the United States, gunshot wounds (GSWs) have become a critical public health concern with substantial annual morbidity, disability, and mortality. Vascular injuries associated with GSW may pose a clinical challenge to the physicians in the emergency department. Patients demonstrating hard signs require immediate intervention, whereas patients with soft signs can undergo further diagnostic testing for better injury delineation. Although digital subtraction angiography is the gold standard modality to assess vascular injuries, non-invasive techniques such as Doppler ultrasound, computed tomography angiography, and magnetic resonance angiography have evolved as appropriate alternatives. This article discusses penetrating bodily vascular injuries, specifically ballistic and stab wounds, and the corresponding radiological presentations.

DIAGNOSTIC IMAGING AND IONIZING RADIATION EXPOSURE IN A LEVEL 1 TRAUMA CENTRE POPULATION MET WITH TRAUMA TEAM ACTIVATION: A ONE-YEAR PATIENT RECORD AUDIT

This audit describes ionizing and non-ionizing diagnostic imaging at a regional trauma centre. All 144 patients (males 79.2%, median age 31 years) met with trauma team activation from 1 January 2015 to 31 December 2015 were included. We used data from electronic health records to identify all diagnostic imaging and report radiation exposure as dose area product (DAP) for conventional radiography (X-ray) and dose length product (DLP) and effective dose for CT. During hospitalization, 134 (93.1%) underwent X-ray, 122 (84.7%) CT, 92 (63.9%) focused assessment with sonography for trauma (FAST), 14 (9.7%) ultrasound (FAST excluded) and 32 (22.2%) magnetic resonance imaging. One hundred and sixteen (80.5%) underwent CT examinations during trauma admissions, and 73 of 144 (50.7%) standardized whole body CT (SWBCT). DAP values were below national reference levels. Median DLP and effective dose were 2396 mGycm and 20.42 mSv for all CT examinations, and 2461 mGycm (national diagnostic reference level 2400) and 22.29 mSv for a SWBCT.

The Utility of Additional Imaging in Trauma Consults with Mild to Moderate Injury

Limiting CT imaging in the ED has gained interest recently. After initial trauma workup for consultations in the ED, additional CT imaging is frequently ordered. We assessed the benefits of this additional imaging. Our hypothesis was that additional imaging in lower acuity trauma consults results in the diagnosis of new significant injuries with a change in treatment plan and increased Injury Severity Score (ISS). The registry at our Level I trauma center was queried from November 2015 to November 2016 for trauma consults initially evaluated by ED physicians. Patients with mild to moderate injuries were included. Injury findings before and after additional imaging were determined by chart review and pre- and postimaging ISS were calculated. Blinded trauma surgeons assessed the findings for clinical significance and changes in treatment. Four hundred and twenty-one patients were evaluated, 41 were excluded. One hundred and forty patients (37%) underwent additional CT imaging. Forty-seven patients (34%) had additional injuries found, with 16 (12%) increasing their ISS (mean 0.54, SD 1.66). Ninety-three per cent of cases resulted in at least one physician finding the new injuries clinically significant; however, agreement was low (κ = 0.095). For 70 per cent, at least one physician felt the findings warranted a change in treatment plan (κ = 0.405). Additional imaging in ED trauma consults resulted in the identification of new injuries in 1/3 of our patient sample. This suggests that current efforts to limit the use of CT imaging in trauma patients may result in significant injuries going undiscovered and undertreated. Further research is needed to determine the risk of attempts to limit imaging.

Radiation Exposure From CT Scanning in the Resuscitative Phase of Trauma Care: A Level One Trauma Centre Experience

OBJECTIVES

The initial management of a trauma patient often involves imaging in the form of x-rays, computed tomography (CT) and other radiographic studies, which expose the patient to ionizing radiation, an entity known to cause tissue injury and malignancy at high doses. The purpose of this study was to use a calculation-based method to determine the radiation exposure of trauma patients undergoing trauma team activation in a Canadian tertiary-care trauma centre.

METHODS

A retrospective chart review was conducted using the Nova Scotia Provincial Trauma Registry. All patients age 16 years old and over who underwent trauma team activation between March 1, 2008 and March 1, 2009 were included. Patients who died prior to imaging tests were excluded. Dose reports for each CT were used to calculate a whole-body radiation dose for each patient.

RESULTS

There were 230 trauma team activations during the study period, of which 206 had CT imaging. Data were available for 162 patients. The mean whole-body radiation exposure for all patients was 24.4±10.3 mSv, which may correlate to one additional cancer death for every 100 trauma patients scanned.

CONCLUSIONS

Trauma patients are exposed to significant amounts of radiation during their initial trauma work-up, which may increase the risk of fatal cancer. Clinicians who care for these patients must be aware of the radiation exposure, and take measures to limit radiation exposure of trauma patients.

Utility of computed tomographic imaging of the cervical spine in trauma evaluation of ground-level fall

BACKGROUND

Computed tomography (CT) of the cervical spine (C-spine) is routinely ordered for low-risk mechanisms of injury, including ground-level fall. Two commonly used clinical decision rules (CDRs) to guide C-spine imaging in trauma are the National Emergency X-Radiography Utilization Study (NEXUS) and the Canadian Cervical Spine Rule for Radiography (CCR).

METHODS

Retrospective cross-sectional study of 3,753 consecutive adult patients presenting to an urban Level I emergency department who received C-spine CT scans were obtained over a 6-month period. The primary outcome of interest was prevalence of C-spine fracture. Secondary outcomes included fracture stability, appropriateness of imaging by NEXUS and CCR criteria, and estimated radiation dose exposure and costs associated with C-spine imaging studies.

RESULTS

Of the 760 patients meeting inclusion criteria, 7 C-spine fractures were identified (0.92% ± 0.68%). All fractures were identified by NEXUS and CCR criteria with 100% sensitivity. Of all these imaging studies performed, only 69% met NEXUS indications for imaging (50% met CCR indications). C-spine CT scans in patients not meeting CDR indications were associated with costs of $15,500 to $22,000 by NEXUS ($14,600-$25,600 by CCR) in this single center during the 6-month study period.

CONCLUSION

For ground-level fall, C-spine CT is overused. The consistent application of CDR criteria would reduce annual nationwide imaging costs in the United States by $6.8 to $9.6 million based on NEXUS ($6.4-$15.6 million based on CCR) and would reduce population radiation dose exposure by 0.8 to 1.1 million mGy based on NEXUS (0.7-1.9 million mGy based on CCR) if applied across all Level I trauma centers. Greater use of evidence-based CDRs plays an important role in facilitating emergency department patient management and reducing systemwide radiation dose exposure and imaging expenditures.

LEVEL OF EVIDENCE

Diagnostic study, level III.

Complete ultrasonography of trauma in screening blunt abdominal trauma patients is equivalent to computed tomographic scanning while reducing radiation exposure and cost

BACKGROUND

Liberal use of computed tomography of the abdomen and pelvis (CTAP) in the screening of blunt abdominal trauma (BAT) has heightened concerns for increased radiation exposure and costs. We sought to demonstrate that in a select group of BAT patients, complete ultrasonography of trauma (CUST) is equivalent to routine CTAP but with significantly decreased radiation and costs.

METHODS

A retrospective analysis of patients screened for BAT from 2000 to 2011 in a Level 1 trauma center was performed. CUST was available from 8:00 AM to 11:00 PM daily, while CTAP was performed thereafter. Decision to perform CTAP or CUST overnight was made by the attending surgeon based on clinical examination. False negatives (FNs) were described as either a negative CUST or CTAP finding, which later required exploratory laparotomy. Medicare rates and previous data were used for the estimation of cost and radiation exposure.

RESULTS

There were 19,128 patients screened for BAT. A total of 12,577 patients (65.8%) initially underwent CUST, and 6,548 (34.2%) underwent CTAP; 11,059 patients (58% of the total BAT patients) avoided a CTAP, yielding an estimated savings of $6.5 million and 188,003 mSv less radiation during the course of the study. Compared with the CTAP group, patients undergoing CUST had lower Injury Severity Score (ISS) (8.1 vs. 9.6), were older (44.7 years vs. 35.2 years), and experienced less traumatic brain injury (61.4% vs. 69.3%) (all with p < 0.002). Mortality was higher in the CUST group (1.8% vs. 1.2%, p = 0.02), but it was insignificant when adjusted for age older than 65 years (1.1% vs. 0.9%, p = 0.23) or head injury (0.6% and 0.3%, p = 0.4). FN CUST and FN CTAP were 0.29% and 0.1%, respectively (p = nonsignificant), with similar mortality (20% vs. 0%, p = 0.44).

CONCLUSION

CUST is equivalent to routine CTAP for BAT screening and leads to an average of 42% less radiation exposure and more than $591,000 savings per year.

LEVEL OF EVIDENCE

Diagnostic study, level IV; therapeutic/care management study, level IV.

Best Practice in Diagnostic Imaging after Blunt Force Trauma Injury to the Cervical Spine: A Systematic Review

INTRODUCTION

The aim of this study was to investigate best practice in evidence-based clinical examinations to determine the diagnostic efficacy of plain radiography, computed tomography (CT), and magnetic resonance imaging (MRI) of a cervical spine injury after blunt force trauma.

METHODS

A systematic review of recent literature was performed, with the intention of analysing only original research articles focusing on at least two imaging modalities or clinical decision guidelines in relation to blunt force trauma injuries involving the cervical spine. The search used the following databases: ProQuest Central, ScienceDirect, and Scopus. A total of 18 studies were identified as suitable for review; these were further supported by relevant secondary studies.

RESULTS

It was found that the National Emergency X-Radiology Utilization Study and the Canadian C-Spine Rule are both highly sensitive methods for screening patients after cervical spine injuries. CT was shown to have a higher validity than plain radiography and MRI for the detection of a bony cervical spine injury. MRI is recommended for obtunded or unevaluable patients with suspected neurologic deficit.

CONCLUSIONS

Overall, the literature appears to suggest that individuals with a suspected high risk of injury after examination using clinical decision rules should undergo a cervical CT examination. For patients who are found to have a low risk of injury after clinical decision guidelines, good-quality plain radiography is recommended as sufficient.

Cumulative radiation dose due to diagnostic investigations in seriously injured trauma patients admitted to critical care

A retrospective review of case notes and radiology records was performed in order to estimate the amount and sources of ionising radiation multiply injured trauma patients are exposed to, during their initial investigations and subsequent critical care admission. Data were available for 431 radiological investigations from 36 patients. Results showed initial emergency department imaging (combined computed tomography (CT) and plain radiographs) contributed 70% of the total radiation dose. Overall, CT scans were responsible for 80% and plain radiographs 15% of the total radiation dose. Plain radiographs performed after the initial resuscitation period contributed the greatest number of investigations but accounted for only 8% of total radiation exposure. Median cumulative effective dose was estimated to be between 16 and 29 millisieverts, resulting in an estimated increased life time risk of carcinogenesis of between 1 in 614 and 1 in 1075 above baseline.

Repeat spine imaging in transferred emergency department patients

STUDY DESIGN

Retrospective study.

OBJECTIVE

Assess frequency of repeat spine imaging in patients transferred with known spine injuries from outside hospital (OSH) to tertiary receiving institution (RI).

SUMMARY OF BACKGROUND DATA

Unnecessary repeat imaging after transfer has started to become a recognized problem with the obvious issues related to repeat imaging along with potential for iatrogenic injury with movement of patients with spine problems.

METHODS

Consecutive adult patients presenting to a single 1-level trauma center with spine injuries during a 51-month period were reviewed (n = 4500), resulting in 1427 patients transferred from OSH emergency department. All imaging and radiology reports from the OSH were reviewed, as well as studies performed at RI. A repeat was the same imaging modality used on the same spine region as OSH imaging.

RESULTS

The overall rate of repeat spine imaging for both OSH imaging sent and not sent was 23%, and 6% if repeat spine imaging via traumagram (partial/full-body computed tomography [CT]) was excluded as a repeat. The overall rate of repeat CT was 29% (7% dedicated spine CT scans and 22% part of nondedicated spine CT scan).An observation of only those patients with OSH imaging that was sent and viewable revealed that 23% underwent repeat spine imaging with 23% undergoing repeat spine CT and 41% repeat magnetic resonance imaging.In those patients with sent and viewable OSH imaging, a lack of reconstructions prompted 14% of repeats, whereas inadequate visualization of injury site prompted 8%. In only 8% of the repeats did it change management or provide necessary surgical information.

CONCLUSION

This study is the first to investigate the frequency of repeat spine imaging in transfers with known spine injuries and found a substantially high rate of repeat spine CT with minimal alteration in care. Potential solutions include only performing scans at the OSH necessary to establish a diagnosis requiring transfer and improving communication between OSH and RI physicians.

LEVEL OF EVIDENCE

4.

Diagnostic radiation exposure of injury patients in the emergency department: a cross-sectional large scaled study

In contrast to patients with underlying cancer or chronic disease, injury patients are relatively young, and can be expected to live their natural lifespan if injuries are appropriately treated. Multiple and repeated diagnostic scans might be performed in these patients during admission. Nevertheless, radiation exposure in injury patients has been overlooked and underestimated because of the emergent nature of such situations. Therefore, we tried to assess the cumulative effective dose (cED) of injury patients in the emergency department. We included patients who visited the emergency department (ED) of a single tertiary hospital due to injury between February 2010 and February 2011. The cED for each patient was calculated and compared across age, sex and injury mechanism. A total of 11,676 visits (mean age: 28.0 years, M:F = 6,677:4,999) were identified. Although CT consisted of only 7.8% of total radiologic examinations (n=78,025), it accounted for 87.1% of the total cED. The mean cED per visit was 2.6 mSv. A significant difference in the cED among injury mechanisms was seen (p<0.001) and patients with traffic accidents and fall down injuries showed relatively high cED values. Hence, to reduce the cED of injury patients, an age-, sex- and injury mechanism-specific dose reduction strategy should be considered.

Radiological work-up after mass casualty incidents: are ATLS guidelines applicable?

OBJECTIVES

In mass casualty incidents (MCI) a large number of patients need to be evaluated and treated fast. Well-designed radiological guidelines can save lives. The purpose of this study was to evaluate the Advanced Trauma Life Support (ATLS) radiological guidelines in the MCI of an aeroplane crash.

METHODS

Medical data of all 126 survivors of an aeroplane crash were analysed. Data included type and body region of the radiological studies performed on the survivors, Abbreviated Injury Score (AIS) and Injury Severity Score (ISS) codes and trauma care level of the hospitals.

RESULTS

Ninety patients (72 %) underwent one or more imaging studies: in total 297 radiographs, 148 CTs and 18 ultrasounds were performed. Only 18 % received diagnostic imaging of all four body regions as recommended by ATLS. Compliance with ATLS was highest (73.3 %) in severely injured victims (ISS ≥16); this group underwent two thirds of the (near) total body CTs, all performed in level I trauma centres.

CONCLUSION

Overall compliance with ATLS radiological guidelines was low, although high in severely injured patients. Level I trauma centres frequently used (near) total body CT. Deviation from ATLS guidelines in radiological work-up in less severely injured patients can be safe and did not result in delayed diagnosis of serious injury.

KEY POINTS

• Radiological imaging protocols can assist the management of mass casualty incidents needs. • Advanced Trauma Life Support (ATLS) radiological guidelines have been developed. • But radiological guidelines have not frequently been applied in aeroplane crashes. • Aircraft accidents are of high energy so ATLS guidelines should be applied. • Following mass casualty incidents total body CT seems appropriate within ATLS protocols.

Analysis of radiation exposure among pediatric trauma patients at national trauma centers

BACKGROUND

Injured children undergo radiologic studies as part of trauma evaluations. Children are more sensitive than adult patients to the effects of ionizing radiation. Few studies have described the radiation exposure to pediatric patients during trauma evaluations. We sought to describe the rate of use of radiology studies and to estimate the effective dose of radiation delivered to pediatric trauma patients presenting to trauma centers within the United States.

METHODS

We performed an analysis of pediatric patients younger than 19 years who presented to an American College of Surgery-verified trauma center in 2010 (National Trauma Data Bank). We excluded patients who were transferred from another facility, patients who died at the scene or those who presented to the emergency department dead on arrival. We examined the use of computed tomography (CT) and standard radiographs (x-ray). Radiologic studies were identified through common procedure codes (CPT). Using published criteria, we estimated the effective radiation dose per trauma patient.

RESULTS

Among the 84,863 eligible pediatric trauma patients, 26,360 (31.1%) underwent imaging with x-ray or CT. Of these patients, 17,321 (65.7%) were male, median age was 13.0 years (interquartile range, 6.0-17.0), and 20,965 (79.5%) had an Injury Severity Score (ISS) of less than 16. A total of 23,148 (27.4%) underwent CT. X-ray studies accounted for a small amount of exposure to radiation as compared with CT. Mean (SD) effective radiation exposure of patients imaged with CT was 12.0 (8.2) mSv. Younger children and those with increasing injury severity were exposed to higher doses of radiation (β = -0.04, p < 0.001).

CONCLUSION

The majority of radiation exposure to pediatric trauma patients is secondary to CT. Younger children and those with more severe injuries are exposed to higher doses of radiation. Pediatric trauma patients are exposed to levels of radiation, which could potentially lead to long-term harm.

LEVEL OF EVIDENCE

Epidemiologic study, level III.