Cerebral perfusion alterations and cognitive decline in critically ill sepsis survivors

We investigated the association between cerebral perfusion perturbations in sepsis with possible cognitive decline (CD) after patients' discharge from the intensive care unit (ICU).

We studied 28 patients with sepsis and Lawton's Instrumental Activities of Daily Living scale (IADL) scores ≥5 who were discharged from a university ICU institution. We evaluated cerebral circulatory parameters (pulsatility index (PI) and cerebral blood flow index (CBFi) was calculated based on the measured velocity of the middle cerebral artery. Use of the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) test was performed daily, and either the Mini Mental State Examination test (MMSE) or Clock Drawing test was performed at ICU discharge. CD was categorized as persistent coma, positive CAM-ICU test at discharge, MMSE <24, or an abnormal Clock test.

Patients had a median pre-ICU IADL score of 6.3 (95% CI 5.9-6.7). Fourteen patients (50%) had CD at discharge. Two were in persistent coma despite sepsis resolution. Information recall was the most affected mental function of the other 12 patients. Only on the first day, patients with CD had higher PI and lower CBFi compared to those without CD (2.2 ± 0.7 vs. 1.4 ± 0.5, p = 0.02; 363 ± 170 vs. 499 ± 133, p = 0.03, respectively). Multivariable analysis revealed delirium, but not PI, as an independent prognostic factor for CD (OR: 29.62, 95%CI 1.91-458.01, p = 0.01).

Delirium, but not cerebral perfusion alterations, is an independent risk factor for cognitive impairment in septic patients who were discharged from the ICU.