The number of adverse events related to contrast-enhanced CT are not statistically different between patients who fasted or who ate beforehand.
It may not be necessary for cancer patients to fast prior to undergoing contrast-enhanced CT, according to a study published in the American Journal of Roentgenology.
Researchers from Brazil performed a prospective study to evaluate the effects of preparative fasting prior to contrast-enhanced CTs for patients with cancer. A total of 3,206 patients were randomly assigned to one of two groups; 1,619 fasted for at least 4 hours prior to their procedure and 1,587 consumed a light meal before undergoing the scan.
The results showed 45 patients (1.5 percent) in the fasting group reported adverse events, compared with 30 patients (0.9 percent) in the non-fasting group. The most common adverse events were:
• Nausea: 32 patients
• Weakness: 12 patients
• Vomiting: 5 patients
The authors noted that the frequency of symptoms between the two groups did not differ statistically significantly.
They concluded that among their sample group, there were few adverse reactions associated with eating a light meal before undergoing a CT scan with an IV contrast agent. “These results support the idea that preparation for contrast-enhanced CT can be simplified, decreasing the discomfort and inconvenience experienced by patients,” they wrote.
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