a b s t r a c t

Introduction: The iodinated Contrast material (ICM) shortage of 2022 has affected healthcare systems worldwide, forcing institutions to adapt by implementing interventions to conserve ICM without compromising patient care. We aim to present the practices proven to be effective in reducing ICM consumption to improve resource alloca- tion in trauma patients.

Methods: A literature search of PubMed, Google Scholar, and Cochrane was conducted. Studies investigating the utility of ICM in the management of trauma & emergency surgery patients, as well as institutional interventions that were implicated as a response to the ICM shortage of 2022 were included for review.

Results: Eight articles were selected and reviewed. The use of alternative, non-contrast-enhanced imaging modal- ities, particularly non-contrast-enhanced CT (NECT), was found to be effective in reducing ICM consumption. Other institutions have implemented strategies to reduce the ICM dose for each Imaging study performed, including decreasing ICM dose itself as well as reducing tube voltage, which was shown to reduce ICM use by 50%. Waste minimization by splitting single-dose contrast vials into smaller aliquots utilized for multiple imaging studies has also been an effective method. Additionally, assembling a Radiology Command Center Team, respon- sible for monitoring ICM supplies while offering 24/7 consults regarding options for alternative imaging, has resulted in an overall reduction in contrast consumption of 50% in 7 days.

Conclusion: In response to the ICM shortage of 2022, most healthcare institutions have found the use of alterna- tive imaging modalities to be effective in reducing ICM consumption. Other effective measures include ICM dose reduction and ICM waste minimization.

(C) 2022

1. Introduction

intravenous iodinated contrast is essential for identifying hemor- rhage in trauma patients, as nearly 94% of hemodynamically stable trauma patients undergo a whole-body computed tomography (CT) scan with contrast prior to surgical intervention [1]. As an essential im- aging modality in Advanced Trauma Life Support, it is highly diagnostic for the course of action trauma surgeons chose to pursue [1]. With care- ful contrast delivery, arterial enhancement of the head, chest, abdomen, and pelvis is achievable, allowing solid organ enhancement for evalua- tion and directed response to blunt or penetrating trauma [1].

* Corresponding author at: Department of Surgery, Division of Trauma and Surgical Critical Care, Orlando Regional Medical Center, 86 W Underwood St., Orlando, FL 32806, USA.

E-mail address: Adel.elkbuli@orlandohealth.com (A. Elkbuli).

Physicians are facing difficult decisions due to the shortage of iodin- ated contrast material (ICM) announced in early April 2022. General Electric is a major supplier of many U.S. hospitals ICM, which announced the closure of its Shanghai, China plant due to the recent spike in SARS- CoV-2 cases there this spring. Trauma surgeons are particularly affected due to the integral part contrast media plays in the diagnostic workup of trauma patients [1]. For example, detecting blunt aortic injuries (BAI) can be confirmed in suspected patients by CT with contrast given that preliminary chest radiographs may not always demonstrate mediastinal widening [2]. If BAI is suspected, the Eastern Association for the Surgery of Trauma (EAST) strongly recommends utilizing CT with IV contrast for evaluation [3]. CT with IV contrast may also detect additional chest wall injuries such as cardiac tamponade, pulmonary embolism, pleural effusion, and sternal/rib fractures [2]. In the setting of trauma, CT with contrast is an essential part of the diagnostic workup of emergent patients [1].

https://doi.org/10.1016/j.ajem.2022.11.016

0735-6757/(C) 2022

Such a shortage of ICM is unprecedented. Hospitals across the globe are rapidly implementing task forces to ration and triage how contrast media can be effectively utilized. Limited evidence in the literature sug- gests that imaging without contrast is most appropriate in the setting of low-risk injuries (i.e., falls) or in patients with contraindications to con- trast. However, higher-risk injuries, such as Motor vehicle collisions (MVC) may warrant contrast-enhanced imaging to better visualize im- portant anatomical structures [4]. The aim of this narrative review is to present institutional practices that have been effective in reducing ICM consumption to improve resource allocation in trauma patients and to better define patients that warrant immediate use of contrast- enhanced imaging.

1. Methods
   1. Search strategy and study selection

The literature search was conducted using the following databases: PubMed, Google Scholar, and Cochrane. All literature published through August 5th, 2022, was included in the search. A total of 2036 studies were identified using the following keywords: “IV Contrast Shortage 2022” OR “Iodinated Contrast Media Shortage” OR “IV Contrast Trauma” OR “IV Contrast Emergency Surgery” OR “IV Contrast Guidelines” OR “Iodinated Contrast Media Trauma” OR “Iodinated Contrast Media Emergency Surgery”.

• 1. Eligibility criteria

The following study designs were included for review: randomized- controlled trials, prospective studies, retrospective studies, systematic reviews, and narrative reviews. Studies investigating the utility of IV contrast in the management of trauma patients and patients undergo- ing emergency surgery were included for review. Studies investigating the effect of institutional interventions that were implicated as a response to the IV contrast shortage of 2022 were also included for review. Studies not investigating IV contrast practices in the patient populations of interest or those studies not investigating institutional responses to the IV contrast shortage of 2022 were excluded from this review. Case reports, commentaries, opinion pieces, non-peer- reviewed studies, and studies written in languages other than English were also excluded.

• 1. Data collection

The initial literature search, abstract screening, full-text review, and data collection processes were conducted by AR, RA, JC, and AE. Data re- garding the year of publication, study design, population, and location of the study was collected from the studies meeting eligibility criteria. The risk of Bias assessment was also conducted by AR, RA, JC, and AE. Any discrepancies were discussed and resolved by AR, RA, JC, and AE.

• 1. Risk of bias

The Joanna Briggs Institute (JBI) Critical Appraisal Checklist tool was used to assess the risk of bias for each of the included studies. The cohort studies and qualitative research checklists were used as indicated based on the design of the included studies [5].

1. Results
   1. Study selection and risk of bias assessment

After removal of duplicate studies, abstract screening, and full-text review, a total of 8 studies met eligibility criteria (Fig. 1). The JBI Critical Appraisal Checklist identified 3 studies with a moderate risk of bias and 5 studies with a low risk of bias (Table 2).

• 1. Alternative imaging

Alternative imaging modalities including non-contrast-enhanced CT (NECT), nuclear medicine scans, magnetic resonance imaging (MRI), or ultrasound (US) have been used increasingly by some institutions to minimize the use of ICM. The appropriate utilization of alternate imag- ing is often determined by using the American College of Radiology (ACR) Appropriateness Criteria (Table 1) [6,7].

In a clinical perspective review exploring conservation strategies by the Yale School of Medicine, utilizing NECT for cases of diverticulitis, ap- pendicitis, Bowel obstruction, and abdominal hernias were feasible efforts to conserve contrast. Furthermore, NECT may be appropriate for oncolog- ical staging in certain situations (i.e. high probability for metastasis to the peritoneum, bones, and lymph nodes) [7-9]. Additionally NECT has been used for perforated viscus as well as minor chest and abdominal trauma based on clinical judgment [8,9]. Salazar et al. found that NECT was an ac- ceptable follow-up for stable Abdominal aortic aneurysm and post- Endovascular repair [9]. One hospital saw a 34% reduction in the number of contrast-enhanced CTs seen between March to May of 2022 due to the emphasis on utilizing NECT examinations in non-Traumatic cases [6].

Alternative imaging such as nuclear medicine has been recom- mended for gastrointestinal bleeding, occult infection, pulmonary embo- lism (PE), and certain malignancy staging [7]. Cavallo et al. utilized nuclear medicine for non-emergent cardiac ischemia workup [7]. In a qualitative review of two major hospitals in Australia, Amukotwa et al. implemented a triaged approach to PE evaluation, often leading to ventilation-perfusion scans (nuclear medicine) as an alternative to CTA in certain clinical scenarios. Conversely, contrasted imaging remains the study of choice for cardiac ischemia workup in emergent cases [8].

In the evaluation of Cerebrovascular accidents (CVAs), the use of MRI in the evaluation should be considered when possible. Time of day, MRI staff availability, and timing (within 30 min) should be considered. However logistical issues may arise due to increased demand for MRI service and should also be considered when choosing this imaging mo- dality [10]. MRI can also be an adequate imaging modality for RUQ pain and stable descending thoracic aortic dissection [9].

Ultrasound has been suggested for the evaluation of kidney, pancre- atic, and focal liver lesions [7,8]. Ultrasound is also an acceptable imag- ing modality for imaging the neck and vasculature of the limbs and abdominal vessels in emergent and non-emergent cases [8].

In an Australian public hospital, the utilization of alternative imaging modalities lead to a reduction of the number of inpatient and ED CECTs to 68.8% of the original value (p < 0.01) An increase of NECT (41.6%), NECT abdomen & pelvis (608.2%), and nuclear medicine scans (165.8%) (p < 0.01) was also seen [11]. A retrospective study at this in- stitution confirmed the decrease in mean daily usage of CECT from 112 to 44 total examinations, with the largest decrease in abdominopelvic CECT (91%) (p < 0.05) [12]. The utilization of alternate methods of im- aging was monitored, which identified an increase in the mean use of unenhanced CT (145 vs 101 exams), ED or inpatient unenhanced CT (119 vs 83 exams), unenhanced abdominopelvic CT (20 vs 3 exams),

and ventilation-perfusion scanning (7 vs 2 exams) (p < 0.05) [12].

• 1. Alterations in contrast dosage

Another alternative that has been considered as decreasing the con- trast dosage given with CECT [9]. Various methods to decrease the dos- age without decreasing Image quality were examined. Dosing by weight was utilized by various institutions and was found to be effective [6-8]. Using the lowest dose possible is effective when determined with assis- tance from technologists, physicians, and physicists if available [13]. To preserve imaging quality, reducing tube voltage was also utilized, which allows for reduced ICM without sacrificing image quality [7,10]. One in- stitution found that decreasing tube voltage decreased ICM usage by 50%, but increased the radiation dose administered to the patient’s skin [8]. Utilization of Dual-energy CT, with a reduction in contrast

Identification of studies via databases

Fig 1. PRISMA diagram demonstrating the literature search process and final study inclusion for this narrative review.

Records undergoing full-text assessment for eligibility

(n =29)

Studies included in review

(n =8)

Records excluded

(n = 21)

Records excluded

(n = 1,998)

Records screened

(n = 2,027)

Records remaining after removal of duplicates

(n = 2,027)

Records identified through databases

(n = 2,036)

PubMed: 1,882

Google Scholar: 26

Cochrane: 128

Included

dose, was also utilized when possible [6,8,9]. Usage of wide-detector CT for stroke evaluation has also been implemented [10]. Discussion of contrast dilution was suggested as a potential ICM Reduction method at one institution but was not universally implemented [13].

Identification

Screening

Eligibility

After the implementation of ICM dose reduction methods, the mean ICM volume per CECT decreased from 88 mL to 74 mL (p < 0.05), and Contrast agents“>daily ICM use decreased from 9.9 L to 3.3 L (p < 0.05). Notably, this study determined that CECT utilization reduction measures via alterna- tive imaging modalities contributed more to ICM use reduction than did ICM dose reductions. These measures did not decrease overall ICM waste and were not as effective in the imaging of obese patients [12].

• 1. Minimization of waste

Strategic repackaging to minimize ICM waste has also been imple- mented in various hospitals [7]. As most ICM comes in single-use vials, efforts to redistribute large vials into various smaller vials have been ef- fective, allowing the ICM to be split and utilized by multiple patients [6,7,13]. In order to minimize the risk of infection, guidance is offered by the CDC on how to perform this properly to minimize the risk of in- fection [6]. Repackaging into smaller volume aliquots is often overseen

and approved by each institution’s infection prevention team [13]. One hospital system found an alternative way to use multi-use vials, by using Namic contrast management devices and Namic spikes to en- able multi-use contrast vials within the space of 6 h. This was effective for 500 mL omnipaque 300 and 350 vials, as well as split 100 mL vials to be utilized for two CECT exams [9].

• 1. Alternate contrast agents

ICM is generally the agent of choice for oral contrast material [7]. How- ever, Cavallo et al. have used Readi-Cat barium sulfate suspensions or manual dilution of contrast agents for oral-contrast needs [7]. Salazar et al. found that switching oral contrast was effective for post-op abdom- inal CT if concern for bowel leak is present [9]. Oral contrast was switched from iohexol to gastrografin or Breeza when possible [9]. Gastrografin has also been utilized in fluoroscopic procedures at some institutions [7].

• 1. Modification of institutional protocols

One of the greatest endeavors of hospitals globally is to set institu- tional protocols in place to control ICM usage in the face of this shortage.

Table 1

Displays alternative imaging modalities such as non-contrast enhanced computed tomog- raphy (NECT), nuclear medicine (NM), magnetic resonance imaging (MRI), and ultra- sound (US), with their respective cases.

determine the risk of contrast depletion on a daily basis by regularly updating a tier system to determine the use of contrast in outpatient im- aging accordingly [13]. These strategies implemented by the RCCT team

resulted in a 50% contrast reduction in <7 days [13].

Alternative Imaging Acceptable cases

Non-contrast enhanced CT (NECT) -Diverticulitis

-Appendicitis

-Abdominal hernias

-Bowel obstructions

-Certain oncology staging

-Perforated viscus

-Minor chest and abdominal trauma

-Follow up of stable abdominal aortic aneurysm

-Post endovascular repair

-Non traumatic cases

Nuclear Medicine (NM) -Gastrointestinal bleed

-Occult infection

-Pulmonary embolism

-Certain oncology staging

-Cardiac ischemia workup

Although not preferred, deferment of non-emergent imaging has also been implemented at various institutions globally [7-9]. Institu- tions recognize the risk of deferring imaging in these low-risk patients as they may be lost to follow-up [7]. However, prioritization of more emergent imaging is recognized as critical during this shortage [9].

Bammer et al. evaluated requiring attending neurologists to order imaging in the setting of suspected CVA [10]. They found that this re- duced multimodal CECT ordering by 43% in 48 h after intervention and resulted in an increase in the ratio of positive findings to the num- ber of CT scans ordered to evaluate for stroke from 8% pre-intervention to 25% post-intervention [10].

1. Discussion

Magnetic Resonance Imaging (MRI)

-Cerebrovascular accident

-RUQ pain

-Stable descending thoracic aortic dissection

This review found that common approaches to mitigating the ongoing contrast shortage employed by institutions include alternative

imaging and modified contrast dosages [6,7,9,12]. Most commonly,

Ultrasound (US) -Focal liver lesions

-Kidney lesions

-Pancreatic lesions

-Neck imaging

-Abdominal vessels

-Extremity vasculature

At the forefront of one institution is a radiology command center team (RCCT), which consists of six physicians and two administrative person- nel; through collaborating with other hospital departments, there is improved communication regarding current ICM stores, use, and recog- nition of the impacts of implemented institutional protocols [13]. The RCCT continuously develops strategies to mitigate contrast use and pri- oritize which departments and which patients receive contrast when necessary; they are on call 24/7 as consultants for alternate imaging modalities based on ACR Appropriateness Criteria [13]. They also

Table 2

Joanna Briggs Institute (JBI) Critical Appraisal Checklist Tool to assess risk of bias. Among the eight studies reviewed, three were categorized as moderate risk with the remaining five categorized as low risk.

non-contrast-enhanced CT (NECT) was recommended to evaluate non-traumatic cases, which led to a substantial reduction in contrast- enhanced CT orders [6,12]. Other alternative image modalities include nuclear medicine, magnetic resonance imaging (MRI), and ultrasound (US) which may be utilized in specific scenarios, such as non- emergent cardiac evaluations, or evaluating gastrointestinal lesions [7,12]. Although reductions in contrast dosage resulted in lower daily usage, alternative imaging was more successful in conserving contrast than dose alterations [12]. Although both interventions were successful, their impact on patient outcomes was not assessed. Of the literature supporting dose reduction, strategies have involved dosing by weight or reducing tube voltage to preserve image quality [7,10]. Finally, other approaches, although less common, have involved the minimiza- tion of waste (single-use vials for multiple patients), modifications of institutional protocols (i.e., creation of radiology command centers), or using alternate contrast agents (i.e., gastrografin) [7,9,13].

Of the strategies to conserve contrast, alternative imaging modalities are of particular interest. As emergency departments have grown busier, many clinicians have relied less on clinical examination to eval- uate and triage patients. Instead, CT scans have become an efficient, and reliable assessment tool to guide management decisions [12]. Of those

Title Joanna Briggs

Institute (JBI) Critical Appraisal Checklist Tool

Risk of Bias

that are contrast-enhanced, abdominal scans are the most frequently ordered. Interestingly, many of the indications, such as diverticulitis and bowel obstruction, may be appropriately evaluated with non- contrast CT scans [12]. Moreover, pulmonary concerns, including nod- ules and interstitial disease, can also be evaluated with non-contrast

A Health System’s Response to the Ongoing Global Shortage of Iodinated Contrast Media

Practice Management Strategies for Imaging Facilities Facing an Acute Iodinated Contrast Media Shortage

Iodinated Contrast Media Shortage: Insights and Guidance from Two Major Public Hospitals

Impact of Iodinated Contrast Media Conserving Interventions and Lessons for the Future

Qualitative Research Qualitative Research

Qualitative Research Qualitative Research

Low Moderate

Low Low

CT scans [12].

However, patients that are classified with level 1 trauma warrant contrast-enhanced imaging, especially if hemodynamically unstable, to detect Life-threatening hemorrhages that require surgical interven- tion. For example, one retrospective analysis compared the utility of CT imaging with and without contrast in detecting splenic injuries [4]. While the sensitivity of non-contrast CT imaging in this context was 93%, many of these cases included nonspecific findings that warranted

Iodinated Contrast Media Conservation Measures

During a Global Shortage: Effect on Contrast Media Use at a Large Health System

Cohort Study Moderate

follow-up assessment [4]. In contrast, enhanced CT imaging demon- strated superior sensitivity with more specific findings [4].

Short-Term Mitigation Steps During the Iohexol Contrast Shortage: A Single Institution’s Approach

Navigating Supply Chain Disruptions of Iodinated Contrast Agent for Neuroimaging and How Business Intelligence Can Help the Decision Process

Rapid Response to the Acute Iodinated Contrast Shortage During the COVID-19 Pandemic: Single Institution Experience

Qualitative Research

Qualitative Research

Qualitative Research

Low

Moderate

Low

Furthermore, an additional retrospective study analyzed the effec-

tiveness of contrast-enhanced CT imaging for trauma patients with BAI [3]. Contrast-enhanced imaging identified any chest injury in more patients compared with CTA (54% vs 46%) [3]. In regard to BAI spe- cifically, contrast-enhanced imaging and CTA were similar in efficacy [3]. Contrast imaging has also shown benefits in identifying anatomical locations of bleeds. A retrospective study by Shanmuganathan et al. re- viewed 26 scans and correctly identified the anatomical location of bleeds with visualization of contrast extravasation [14]. In stable trauma

patients, contrast is useful for surgical planning [14]. The aforemen- tioned discussion further emphasizes the utility of contrast in trauma- relatED presentations and can guide clinicians when ordering scans.

In response to the contrast shortage of 2022, the ACR recommended providers utilize alternative modalities of imaging, including non- contrast CT, ultrasound, MRI, and others, to mitigate the use of contrast [15]. ACR has also advised hospitals to seek other contrast vendors, re- duce contrast dosing, and preserve more highly concentrated contrast for angiography studies [15]. In addition to trauma patients, priority has been given to specialties including cardiology, vascular surgery, ra- diation oncology, gastroenterology, urology, and pain management, as imaging and procedures performed by these specialists are more contrast-dependent [15]. Particularly, in patients with suspected blunt-aortic injury (BAI), contrast-enhanced imaging is still the modal- ity of choice and is supported by the Eastern Association for the Surgery of Trauma (EAST) [3]. In contrast, non-traumatic settings may be an op- portunity to spare contrast use without compromising patient care [12]. Additionally, the American College of Surgeons (ACS) released a state- ment acknowledging the impact of the contrast shortage and has agreed with the ACR’s current recommendations [16].

This review is limited by the paucity of literature regarding this topic. As the contrast shortage is relatively new and rapidly evolving, most of the available articles are opinion pieces regarding the effective- ness of institutional practices that have been implemented since the onset of the shortage. Nevertheless, we implore these institutions to continue exploring responses to the ICM shortage and its impact on pa- tient outcomes. Given the uncertainty surrounding the current short- age, further studies are needed with a higher quality of evidence to recommend effective practices to optimize ICM usage without compromising patient outcomes. As the benefit of ICM has been estab- lished in the management of trauma patients, we also recommend that studies observe the impact of the current shortage on trauma pa- tients specifically. Methods to improve trauma management may be particularly important throughout the current contrast shortage.

1. Conclusion

With the onset of the iodinated contrast shortage in April 2022, healthcare facilities have employed a variety of methods to reduce ICM consumption. One of the most efficacious institutional practices in- volves the utility of alternative imaging modalities as suggested by the ACR Appropriateness Criteria. Other successful strategies include reduc- ing ICM dosage per imaging study as well as implementing methods to reduce waste, including ICM repackaging. Although these interventions have been adopted at some institutions, none have studied their effect on patient outcomes, and thus, further investigations are needed to elu- cidate this relationship. Evaluating the best uses of ICM during this ongoing shortage allows conservation and utilization for emergent patients who are in critical need.

Author contribution

Study design and conception: AE.

Data collection, analysis, and interpretations: AE, AR, RA, JC, LW. Manuscript preparation: AE, AR, RA, JC.

Critical revision of the manuscript: AE, AR, RA, JC, LW, WH. All authors read and approved the final manuscript.

Conflict of interest/disclosures

Authors disclose no competing interest.

Funding/financial disclosure

None.

CRediT authorship contribution statement

Abigail Rosander: Writing – review & editing, Writing – original draft, Resources, Methodology, Investigation, Data curation. Ryan Andrade: Writing – review & editing, Writing – original draft, Method- ology, Investigation, Data curation. Jennifer Concepcion: Writing – review & editing, Writing – original draft, Methodology, Investigation, Data curation. Lucille Woodley: Writing – review & editing, Investiga- tion, Data curation. Will Havron: Writing – review & editing, Supervision, Investigation. Adel Elkbuli: Writing – review & editing, Writing – original draft, Supervision, Resources, Project administration, Methodology, Investigation, Data curation, Conceptualization.

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