Why is an air kerma meter inadequate for determining a sentinel event?

An air kerma meter is designed to measure the amount of radiation energy absorbed in air, which provides an indication of the radiation dose delivered. However, it may not accurately reflect the dose distribution within the patient's body, especially in diverse anatomies. This inability to account for dose spreading is crucial when assessing sentinel events, which often involve specific areas of concern in terms of radiation dose delivery.

In clinical practice, particularly during fluoroscopic procedures, the radiation dose can vary significantly across different tissues depending on factors like beam geometry, patient positioning, and the presence of metal or other structures that can scatter radiation. The air kerma measurement is taken in air and does not consider how the energy interacts with biological tissues, which can lead to an underestimation or overestimation of the actual dose received by the patient in specific organs.

This specificity is particularly important for sentinel events, where the focus is on precise dose distribution that could lead to complications or necessitate further investigation. Therefore, while an air kerma meter provides valuable information, it falls short in situations where accurate assessment of dose spreading within the patient's anatomy is essential for determining the potential impact of radiation exposure.