Altered Mental Status in ICU Patients: Diagnostic Yield of Noncontrast Head CT for Abnormal and Communicable Findings. (Stulce)

Chokshi FH, et al. Altered Mental Status in ICU Patients: Diagnostic Yield of Noncontrast Head CT for Abnormal and Communicable Findings. Crit Care Med. 2016 Dec;44(12):e1180-e1185.

OBJECTIVE: To evaluate the diagnostic yield of noncontrast head CT for acute communicable findings in ICU patients specifically scanned for altered mental status.

DESIGN: Retrospective observational cohort study.

SETTING: University Hospital Neuroscience, Medical, and Surgical ICUs.

PATIENTS: ICU patients with new-onset altered mental status.

INTERVENTION: Noncontrast head CT.

MEASUREMENTS AND MAIN RESULTS: Reports on head CTs from two university hospitals performed for the sole indication of altered mental status in ICU patients between July 2011 and June 2013 were reviewed for 1) acute (new or worsening) hemorrhage, 2) mass effect/herniation, 3) infarction, and 4) hydrocephalus. Subgroup analyses of positive findings were performed by 1) ICU group type, 2) age, and 3) race. A total of 2,486 head CTs were performed in 1,357 patients whose age ranged from 14 to 116 years (median, 59; mean, 57.6 ± 16). Acute communicable findings in at least one of four categories were present in 22.8% (566/2,486) of examinations, with hydrocephalus being most common (11.5% [286/2,486]). The frequency of any acute communicable findings in neuroscience, medical, and surgical ICUs was 28.6% (471/1,648), 9.8% (43/440), and 13.1% (52/398), respectively. Neuroscience ICU head CTs had significantly higher rates of acute communicable findings in all categories, except for acute infarction, compared with the other two ICUs (p < 0.001). Acute hydrocephalus (13.6% vs 7.4%; p < 0.001) and mass effect (6.7% vs 4.3%; p = 0.01) were more common in patients less than 65 years. For other acute categories, no significant difference was noted by age. There was no significant difference in the likelihood of a positive examination by race.

CONCLUSIONS: Almost one in four head CTs in a university ICU patient population performed for primary indication of altered mental status yields abnormal communicable findings. In this patient population, utilization management barriers to examination ordering should be minimized.

Cognition and brain structure following early childhood surgery with anesthesia. (Betters)

Backeljauw B, et al. Cognition and brain structure following early childhood surgery with anesthesia. Pediatrics. 2015 Jul;136(1):e1-e12.

Full-text for Children’s and Emory users.

BACKGROUND: Anesthetics induce widespread cell death, permanent neuronal deletion, and neurocognitive impairment in immature animals, raising substantial concerns about similar effects occurring in young children. Epidemiologic studies have been unable to sufficiently address this concern, in part due to reliance on group-administered achievement tests, inability to assess brain structure, and limited control for confounders.

METHODS: We compared healthy participants of a language development study at age 5 to 18 years who had undergone surgery with anesthesia before 4 years of age (n = 53) with unexposed peers (n = 53) who were matched for age, gender, handedness, and socioeconomic status. Neurocognitive assessments included the Oral and Written Language Scales and the Wechsler Intelligence Scales (WAIS) or WISC, as appropriate for age. Brain structural comparisons were conducted by using T1-weighted MRI scans.

RESULTS: Average test scores were within population norms, regardless of surgical history. However, compared with control subjects, previously exposed children scored significantly lower in listening comprehension and performance IQ. Exposure did not lead to gross elimination of gray matter in regions previously identified as vulnerable in animals. Decreased performance IQ and language comprehension, however, were associated with lower gray matter density in the occipital cortex and cerebellum.

CONCLUSIONS: The present findings suggest that general anesthesia for a surgical procedure in early childhood may be associated with long-term diminution of language abilities and cognition, as well as regional volumetric alterations in brain structure. Although causation remains unresolved, these findings nonetheless warrant additional research into the phenomenon’s mechanism and mitigating strategies.