The relationship of the blood-brain-barrier (BBB) and the clinical diagnosis of delirium have not been established. The aim of the study was to assess the association between delirium using the confusion assessment method for the intensive care unit (CAM-ICU) and a serum marker of BBB integrity (protein S100β)in a group of surgical patients.
Prospective, observational, cohort study. Patients who underwent lung transplantation were included. The CAM-ICU was obtained at baseline and daily for 4 days after transplant. Serum S100β;protein and interleukin-6 (IL-6) were measured. Comparison was made for patients with delirium (D) and without delirium (ND) diagnosed by the CAM-ICU.
21 patients were enrolled from 07/06 to 09/07. Twelve patients were female; the mean age was 52 years (19–65). COPD was the most common indication for lung transplant (38%). No patient had delirium at baseline but 19% (4/21) were diagnosed at some point during the study time. S100β was increased in all patients after transplant. By day 4, the D group had a higher level of S-100β, compared with the ND group (0.420ug/L vs. 0.189ug/L; p=0.0009). In the ND patients, serum S100β returned to baseline four days after transplant and in the D group remained elevated. IL-6 was significant higher in the D group at 48hrs (p=0.022) and the trend remained by day 4. There was a tendency for higher WBC count in the D group at 96hrs post transplant (p=0.082) and a significant neutrophilia (p=0.014). The D group had a higher rate of acute renal failure (BUN, p=0.058; creatinine, p=0.052).
We found an important association between the clinical diagnosis of delirium and elevations of the serum S100β, suggesting a possible disruption of the BBB. We hypothesize that such disruption may be related to the inflammatory response, as indicated by the higher IL-6 levels, WBC and neutrophil counts.
Delirium may be related to a disturbance in the BBB. Such situation may be detected by elevated levels of s100β in serum.
Jose Santacruz, No Financial Disclosure Information; No Product/Research Disclosure Information