What should a technician do if they do not feel the "thrill" during a fistula site assessment?

When assessing a fistula, the presence of a "thrill" is crucial because it indicates that blood is flowing adequately through the access site. If a technician does not feel the thrill, it suggests that there may be an issue with blood flow, such as a clot or occlusion. In this context, an absent thrill indeed implies that the vascular access may be clotted, and attempting cannulation could lead to complications such as damage to the access site or further clotting.

Therefore, the most appropriate action when the thrill is absent is to refrain from cannulation and recognize the need for further assessment to ensure patient safety. This is critical as proceeding with cannulation without adequate blood flow can jeopardize the integrity of the vascular access and the patient's health. Hence, understanding the importance of the thrill and the implications of its absence helps in making informed decisions about patient care.