The volume of contrast media given to patients before Computed Tomography (CT) scans can pose a safety risk. University of Malaya Medical Centre shares about their project to optimise contrast media volume to improve patient safety
At the Asian Hospital Management Awards (AHMA) 2020, University of Malaya Medical Centre (UMMC) was awarded the Gold Award, the highest accolade, in the Patient Safety category. Their winning project submission was on how they optimised the volume of contrast media, used for CT scans, to achieve patient safety and cost effectiveness. We speak with the UMMC team to find out more about their project objectives and results.
The problem: Potential overdose of contrast media
When patients undergo CT scans, they will be administered a special dye, called contrast media, which allows the body area of interest to be seen more clearly. These media could be barium-sulfate, iodine or gadolinium-based. The type of contrast media administered depends on the type of imaging examination and the structures that need to be viewed. Traditionally, a fixed volume of 100ml of iodinated contrast media was administered to all CT patients. However, this causes complications as the patient’s body weight was not taken into consideration. Patients weighing less than 100kg may suffer from overdose effects, such as allergy reactions, extravasation (leakage of fluids from blood vessels), or even kidney failure (a condition named contrast-induced nephropathy, or CIN).
Hospitals worldwide have thus moved to include patient weight as a factor when calculating the contrast media volume to be given. However, there is yet to be a consensus on the exact equation or formulation, with suggestions ranging from 1.1 ml/kg to 2.5 ml/kg.
Trial launched at UMMC
To deduce the optimal dose of contrast media for its patients, the Department of Biomedical Imaging of UMMC embarked on a project in 2018 to reduce the contrast media usage and observe its impact on the quality of CT scan images. This is based on the optimisation principle in the field of radiation protection – namely, As Low As Reasonably Achievable (ALARA) & As Low As Reasonably Practicable (ALARP) – which aims to reduce the risk of harm by ensuring any radiation dose is given at the lowest achievable level, said Ravi Chanthriga Eturajulu, Radiographer Officer at UMMC.
A team of 15 radiographers were selected to form the project team, dubbed CTwarriors. The team set out to reduce the ratio of contrast media to patient weight, from 2ml/kg recommended by the manufacturer, to 1ml/kg, or a 50% reduction. In addition, the bolus tracking method, a technique to optimise timing of imaging by tracking the volume of contrast in the body, is applied to obtain consistent image quality.
The trial was split into three stages: pre-intervention, pilot, and post-intervention. In the pre-intervention stage, a review of the current workflow was conducted, with possible issues identified, such as lack of ownership or awareness of risks. The team then planned for mitigation strategies, such as appointing leaders to take charge of the project, and attending Continuing Medical Education (CME) sessions for better understanding of the issue.
During the pilot phase, 104 patients were given reduced contrast media volume. At this phase, the team noted that there were challenges in extending the trial to certain patients, such as bed-ridden patients whose body weight could not be measured, or patients with certain underlying diseases that require adjustments in protocol.
With the above groups excluded, the team found that for the remaining eligible participants, image quality improved despite the reduction in contrast media, with internal structures showing up better.
Over the period of pilot to post-intervention, reduced contrast media was administered to 6,063 patients, and image quality remained satisfactory.
Spin-offs and future possible applications
The results above showed the two-year-long project was a success in both improving patient safety and achieving cost savings. “There was a 44-70% reduction in contrast media usage and 2-47% reduction in radiation dose, thus lowering the risk of side effects. By doing more with less and maintaining good image quality, this innovative project has enhanced patient safety in UMMC,” said Lilian Poh Poh Yap, Radiographer. The team estimated that besides direct cost savings of RM 109,000 from reduced contrast media, there were also indirect savings from the avoidance of further treatments as well as potential risks of litigation amounting to more than RM 1 million, should patient safety be compromised.
UMMC has gone on to collaborate with two other hospitals, Hospital Selayang, Selangor, and Hospital University Kebangsaan Malaysia Medical Centre (HUKMMC), Kuala Lumpur, for spin-off projects, where the CTwarriors provided hands-on training on the new protocol to the other hospitals’ staff members.
Looking ahead, there are further possible applications of this project that can be explored. “Besides focusing on CT CAP (chest abdomen pelvis), we hope this project can be expanded to other contrasted CT examinations (e.g., multiple phases CT, vascular study, etc.). We also hope to share our project on more platforms and encourage others to do the same in pursuit of patient safety,” said Lilian.
Co-Authors: Lilian Poh Poh Yap, Ravi Chanthriga Eturajulu, Jeannie Hsiu Ding Wong, Nadia Fareeda Muhammad Gowdh, Wei Lin Ng, Eric Chung, Sue Anne Manushya Kaur Foo, Anushya Vijayananthan, Fadhli Mohamed Sani.
Acknowledgement to all staff and CT Team who have assisted in the completion of this project: Ms. Hanizan Ahamad, Ms. Tun Suraiya Tun Abdul Majid, Mr. Mohd Kamil Mohd Fabell, Ms. Intan Shuhada Mohd Fuat, Ms. Suraya Khalid, Ms. Kirthiga Veeramohan, Ms. Priya Kudheravelu, Ms Shalina Sri Karan, Ms. Harpreet Kaur Rajput Balgit Singh, Ms. Nurdiyanah Affindi, Ms. Rozelyn Tey Mei Ai, Ms. Nurfadlina Adila Mohamad and Mr. Mohd Azuan Abd Rashid