Survey of contrast media use in southeastern U.S. hospitals.
Approximately 10% of all imaging studies performed in the United States each year, or about 10 million exams, involve contrast media. Currently, nonionic contrast costs 10 to 15 times more than ionic contrast. For example, 50 mL of iopamidol (Isovue 300), a frequently used nonionic contrast agent, costs approximately $80, compared with $5 for diatrizoate (Renografin 60), an ionic agent. Recent data suggest that more than 70% of all contrast studies are performed with nonionic contrast media. If hospitals were to expand their use of nonionic contrast media with a universal usage policy, the cost of contrast media in the U.S. would increase 10-fold (an estimated $1 billion annually).[1-4]
The purpose of the survey reported in this article was to investigate current contrast usage for hospital radiology departments in the southeastern United States and to identify trends related to contrast media. For reporting purposes, survey results differentiate hospitals by number of beds, classification, profit or nonprofit status and current percentages of ionic and nonionic contrast media usage. The survey also identifies radiology and hospital personnel who determine contrast policy, factors influencing institutional decisions on contrast, methods used to reduce nonionic contrast usage and the percentage of hospitals adopting selective use rather than universal use protocols.
Nonionic contrast media was introduced in the United States in 1984. It gained rapid acceptance because of low reaction rates compared with ionic contrast. McClennan reported a 14% increase in nonionic contrast usage in 1987, a 23% increase in 1988 and a 33% increase in 1989. A 1992 survey of contrast usage by Hopper, Lambe and Matthews reported that 10% to 17% of hospitals surveyed used nonionic contrast media more than 75% of the time.
The largest research study on contrast media reactions documented a greater incidence in the rate of minor reactions from ionic contrast compared with nonionic contrast. However, no significant difference in mortality rates was reported.
Bernardino, Fishman, Jeffrey and Brown researched the effects of ionic contrast reactions on the quality of body CT scans and found the difference in image quality, number of adverse reactions and number of aborted/repeated CT scans performed with iohexol 300 and diatrizoate meglumine 60 are not sufficiently different to warrant conversion to nonionic agents for body scans." Although cost, reaction rates and study quality are factors in contrast media selection, they are only one part of this complex issue. Other issues such as the ethical considerations and legal issues surrounding contrast media also must be examined.
Many radiology department managers are searching for alternatives to their institutions' current contrast media usage policies. Radiology departments often are told by hospital administrators to decrease their use of nonionic contrast media to reduce overall contrast media budgets. One accepted method of limiting nonionic usage is through selective use protocol.
Selective use protocol is designed to identify high-risk patients who would be best served by receiving nonionic contrast media. Ionic contrast media are encouraged for lower-risk patients. A 1993 study by Levin indicated that nonionic contrast usage can be controlled to approximately 28% with the implementation of a strict monitoring protocol. Other studies have measured the impact of selective use protocol on cost. Theoretical comparisons between universal nonionic contrast use and selective use resulted in a 75% cost reduction.
Selective use protocol has been criticized for encouraging deceptive practices such as upgrading basic reaction symptoms to severe reaction descriptors and using ambiguous phrases to justify using nonionic contrast. In addition, the safety of selective use protocol has been questioned because, in a small number of cases, mild allergic reactions have escalated to severe levels.
Zeich suggests that high-risk patients receiving nonionic contrast are safer than low-risk patients receiving ionic contrast. If comfort and safety are considered more important than cost, radiology managers can justify the additional expense of nonionic contrast on the basis that it may be ethically and morally the best way to serve the patient.
Health care, like many other industries in the United States, is driven by technology escalation. Continuing to use one product or service when a more advanced version exists is rarely acceptable. A study by Hopper, Lambe and Matthews suggests that many radiologists accept this way of thinking. Their study compared the use of contrast media by physician groups for CT studies, intravenous pyelograms and venograms. Ionic contrast media was universally administered by 15% of the nonradiologist groups but only 9.8% of the radiologist groups. The study also noted that more than half of the groups reported "less patient pain" as a reason for using nonionic contrast.
A well-documented and underutilized method to reduce the use of nonionic contrast is corticosteroid pretreatment before ionic contrast media is administered. Lasser found that overall reactions can be reduced by delivering two doses of oral corticosteroids before administering intravenous ionic contrast. This inexpensive solution has not been widely accepted, however, because of the inconvenience and delays associated with it.
Reducing the amount of contrast media administered is another viable way to limit contrast media costs. A comparative study by Gavant, Ellis and Kleges suggests that using smaller doses of higher iodine concentration levels will produce equivalent diagnostic films for excretory urograms. A similar study for dynamic abdominal and pelvic CT scans found no significant difference in the image quality when using 125 mL doses of ioversol 320 and 150 mL doses of iopamidol 300.
If financial and competitive pressures force hospital administrators to re-evaluate their contrast media policies, radiologic technologists will need to understand the implications. A shift to increased use of ionic contrast will have a major impact on radiographers in both traditional and nontraditional settings. Because contrast usually is administered by radiographers, they need to be aware of possible complications and reactions associated with all types of contrast. Patient assessment skills will become even more critical for radiographers, who should be aware of reaction frequency, symptoms and appropriate responses.
Materials and Methods
A descriptive survey of current contrast media usage was mailed to 150 hospitals located in five southeastern states: Virginia, North Carolina, South Carolina, Georgia and Florida. The sample of 150 hospitals out of a total of 675 listed in the 1994 American Hospital Association guide resulted in a sample size of 22.2%. The sample distribution based on number of hospital beds was as follows: 28 hospitals (18.6%) with 0 to 99 beds, 17 hospitals (11.3%) with 100 to 199 beds, 10 hospitals (6.6%) with 200 to 299 beds, 26 hospitals (17.3%) with 300 to 399 beds, 28 hospitals (18.6%) with 400 to 499 beds, 14 hospitals (9.3%) with 500 to 599 beds, 15 hospitals (10%) with 600 to 699 beds, and 12 hospitals (8%) with more than 700 beds.
An original questionnaire was reviewed by two radiology managers, one from a small rural hospital and the other from a large regional medical center. Based on the reviewers' comments, the questionnaire was revised to combine contrast use in all modalities and overall percentages of ionic and nonionic contrast media use.
The first mailing occurred in October 1995. The mailing consisted of a cover letter identifying the purpose of the research, general instructions, return deadline, the two-page questionnaire and a stamped, self-addressed return envelope. After an initial response period of 3 weeks, a second identical questionnaire was mailed to nonresponding hospitals. Radiology managers were the primary source of information for each institution. To increase the study's response rate, the accompanying cover letter asked the radiology manager to forward the questionnaire to the technical supervisor if necessary.
The survey instrument asked questions about institutional classification and size, contrast utilization policy, primary decision maker, current and projected contrast media use and factors influencing the institution's contrast media policy. The survey was conducted in two separate mailings over a period of 2 months.
Of 150 surveys mailed, responses were received from 79 hospitals, resulting in a 53% response rate. The initial mailing resulted in 71 responses and the second mailing resulted in eight additional responses. Seventy-nine responses represented 11.7% of the total survey population (675 hospitals). Of the 79 respondents, 15 hospitals were government-affiliated. Nine of the government-affiliated hospitals were designated as local or community hospitals, while six were state-affiliated. Of the remaining 64 hospitals, 63 were classified as private. One hospital did not report any classification. The private hospitals included 53 nonprofit institutions and 10 for-profit facilities.
For reporting purposes, the hospitals were further differentiated by size. Of the 79 hospitals that responded to the survey, 14 (17.7%) had 0 to 99 beds, eight (10.1%) had 100 to 199 beds, two (2.5%) had 200 to 299 beds, 10 (12.6%) had 300 to 399 beds, 13 (16.5%) had 400 to 499 beds, 13 (16.5%) had 500 to 599 beds, eight (10.1%) had 600 to 699 beds, and 11 (13.9%) had more than 700 beds.
The questionnaire asked respondents to identify overall contrast usage for their institution. No differentiation was made for study type, procedure or modality. Seventy-seven hospitals included contrast frequency in their responses, while two did not report on this item. Seventy-one percent (55/77) of these hospitals reported that they used nonionic contrast at a frequency greater than 75%, while 43% (33/77) reported using nonionic contrast 100% of the time. Twenty-three percent of hospitals reported using ionic contrast at least 50% of the time.
Contrast usage also was differentiated by number of beds. Sixty percent of hospitals with fewer than 399 beds used nonionic contrast 100% of the time. In contrast, only 35% of hospitals with more than 400 beds adopted a universal nonionic contrast policy. The survey indicated more frequent use of nonionic contrast by smaller hospitals. (See Table 1.)
Table 1 Percentage of Nonionic Contrast Media Usage No. of 100% >75% >50% <50% Not Beds usage usage usage usage reporting 0-99 71% 14% 8% 0% 7% 100-199 72% 9% 9% 10% 0% 200-299 50% 50% 0% 0% 0% 300-399 30% 40% 0% 30% 0% 400-499 31% 15% 8% 39% 7% 500-599 23% 62% 0% 15% 0% 600-699 38% 25% 12% 25% 0% >700 55% 18% 9% 18% 0%
Sixty percent of for-profit hospitals used nonionic contrast more than 75% of the time, while nonprofit hospitals used nonionic contrast at a rate of 71%. Government-affiliated hospitals had the highest rate of nonionic contrast usage, with 85% of these hospitals reporting that they used nonionic contrast more than 75% of the time.
When asked to identify the people directly involved in establishing a contrast usage policy for their institution, 42% of respondents reported that the radiologist was the sole decision maker for contrast policy. The second largest group was a combination of the radiologist and radiology department manager (30%), while 14% reported the radiology manager or hospital administrator was primarily responsible for contrast policy. Committees and other hospital personnel comprised the remaining 14%.
The survey also identified methods to control costs and limit the use of nonionic contrast. Forty-three percent of the responding hospitals said they used some type of selective use policy. Other methods used to reduce nonionic contrast usage were prestudy corticosteroids in conjunction with ionic contrast media (13%) and decreased volume/increased concentration method (16%).
Each respondent ranked factors that influence their institution's contrast policy by selecting from the following items:
* Cost of contrast.
* Decreased reactions.
* Patient considerations.
* Medical/legal liabilities.
Most respondents reported that "decreased reactions" were the most important factor influencing policy. (See Table 2.) The least important factor was cost, but this factor varied by hospital size. Only 3% of hospitals with fewer than 400 beds reported cost was the primary factor in selecting contrast media, while 27% of hospitals with more than 400 beds rated cost as the primary influence in contrast media selection.
Table 2 Factors Influencing Contrast Policy Cost of Decreased Patient Legal contrast reactions factors liability Most 19% 44% 14% 18% important (1 on scale of 1 to 4) Least important 42% 6% 19% 26% (4 on scale of 1 to 4)
Respondents also were asked to identify the person responsible for administering contrast at their institution. At 90% of hospitals, radiographers actively administered some form of intravenous contrast media. Radiologists and nurses administered contrast at 40% and 29% of hospitals, respectively. (See Fig. 1.) There was a slight decrease in the amount of contrast administered by nurses after hours. Whether during normal day shift hours or after hours, the frequency of radiographer and radiologists injections remained constant.
[Figure 1 ILLUSTRATION OMITTED]
This study reflects 53% of the sample and 11.7% of the total population. Because it did not differentiate between specialties or procedures and was targeted at radiology departments, the survey may not include areas like cardiac catheterization and/or interventional radiology. Jacobson's study reported these areas use nonionic contrast at a rate of 75% to 85%. Additional surveys with more detailed questionnaires and larger sample sizes could further our understanding of current contrast usage and related issues impacting hospitals.
The results of the survey reported in this article are in line with a 1994 study by Jabobson and Rosenquist. Nonionic contrast remains the media most often administered. However, the survey showed an increase in hospitals using universal nonionic policy from the previous study conducted in 1992 by Hopper, Lambe and Matthews. The survey reported here also reflects a larger number of hospitals using selective use protocol. This may be due to standardization of selective use protocols by the American College of Radiology.
The discrepancy of nonionic contrast usage between large and small hospitals may identify a trend for contrast use. Although cost is not the most important criterion when selecting contrast agents, it does pose a particular problem to large hospitals. Large hospitals faced with contrast expenditures in excess of $1 million annually are reducing nonionic use, thus changing the standard of care. For financial and competitive reasons, the smaller hospitals may follow the lead of the larger institutions and decrease their use of nonionic contrast media. Even with a decrease in nonionic contrast media, it is unlikely that ionic contrast use will surpass nonionic contrast use because the number of contrast reactions is still the major factor for individuals who determine contrast usage policy.
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Douglas P. Utter, R. T. (R), is a staff technologist in the Department of Radiology at Duke University Medical Center, Durham, N.C.
Partial financial assistance for the research reported in this article was provided by the University of North Carolina Division of Radiologic Science.
Reprint requests may be sent to the American Society of Radiologic Technologists, Publications Department, 15000 Central Ave. SE, Albuquerque, NM 87123-3917.
[C] 1997 by the American Society of Radiologic Technologists.
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|Author:||Utter, Douglas P.|
|Date:||May 1, 1997|
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