UCSF

Background

Patients admitted to an intensive care unit (ICU) with a primary neurologic disorder often receive multiple radiation-based diagnostic studies of the head and neck. Although radiation exposure puts them at risk of intracranial and neck tumors, the amount of radiation received is largely unknown.

Methods

We sought to accurately collect cumulative radiation exposure data from radiation-based studies in a retrospective cohort of patients admitted to the neuroscience ICU (NICU) at a single institution. Radiation doses of studies were converted to estimated effective doses in mSv via literature-published formulas. To impact ordering practices, we piloted an educational initiative on patient radiation exposure to a cohort of physicians caring for patients with a diagnosis of acute subarachnoid hemorrhage. Patients were randomized to have radiation exposure data posted at the bedside for physician viewing.

Results

We identified 641 patients from July 2010 to March 2011 who had received at least 1 computed tomography-based study of the head. Patients received on average 18.4 mSv of radiation from head and neck imaging. Patients with subarachnoid hemorrhage received the highest average levels of radiation exposure (37.1 mSv). Attributable risk of carcinogenesis was estimated to be low. A pilot educational initiative did not reduce the total estimated effective dose per patient.

Conclusions

Accurate reporting of estimated effective doses for NICU patients is feasible and can be provided to ordering physicians to assist with clinical decision making and potentially lower exposure risk. Further strategies are needed to reduce unnecessary radiation exposure at the physician ordering level.