To investigate whether computed tomography chest (CTC) obtained with neuroimaging during stroke evaluation is superior to a single anteroposterior chest x-ray (CXR) in detecting occult aspiration secondary to neurological aspiration pneumonia (NAP).

Ventilator Associated Pneumonia (VAP), occurring 48-hours after endotracheal intubation, is a national benchmark for quality care in intensive care units (ICU). Patients with severe, acute neurological injury admitted to neurological ICU (NeuroICU) have higher VAP rates than other ICUs, with causation poorly understood. Patients with dysphagia or impaired level of consciousness at stroke ictus often aspirate. CTC, within 48-hours of admission, could identify occult aspiration earlier than CXR, thereby classifying infiltrates as NAP rather than VAP.

We conducted a prospective, observational, quality improvement study (NAP-VAP) of stroke patients (ischemic/hemorrhagic) admitted to one academic hospital NeuroICU and intubated within 24-hours. Admission CXR and CTC were obtained at time of neuroimaging, either as an adjunctive study or part of stroke evaluation, and dichotomously graded “positive” or “negative” for infiltrate by a radiologist blinded to the patients' clinical condition and diagnosis.

A convenience sample of 30 stroke patients (17 male; 13 female; mean age 53.5 years [range 23-82]) was comprised of aneurysmal subarachnoid hemorrhage (19), intraparenchymal or intraventricular hemorrhage (7), acute ischemic stroke (3), and sagittal venous sinus thrombosis (1), with CXR/CTC both positive for infiltrate (4), CXR/CTC both negative (10), CXR positive and CTC negative (1), CXR negative and CTC positive (15). Sensitivity and specificity of identifying infiltrates on CTC were 21% and 90%, respectively. Positive and negative predictive values were 80% and 40%, respectively. Accuracy of identifying infiltrates on CTC was 46.7%.

CTC obtained simultaneously with neuroimaging during stroke evaluation appears to reveal occult aspiration compared to a single anteroposterior CXR. These preliminary results have significant implications on classification of a later developing pneumonia as NAP rather than VAP.