Citation

Nakagawa K, Hills NK, Kamel H, Morabito D, Patel PV, Manley GT, Claude Hemphill J. Neurocrit. Care 2011; 15(1): 101-106.

Affiliation

Department of Neurovascular Service, University of California San Francisco, 505 Parnassus Avenue, M-830, San Francisco, CA, 94143-0114, USA, kazuma.nakagawa@ucsfmedctr.org.

Copyright

(Copyright © 2011, Holtzbrinck Springer Nature Publishing Group)

DOI

10.1007/s12028-010-9446-y

PMID

21061187

Abstract

BACKGROUND: Animal studies have shown that even a small temperature elevation of 1°C can cause detrimental effects after brain injury. Since the skull acts as a potential thermal insulator, we hypothesized that decompressive hemicraniectomy facilitates surface cooling and lowers brain temperature. METHODS: Forty-eight patients with severe brain injury (TBI = 38, ICH = 10) with continuous brain temperature monitoring were retrospectively studied and grouped into "hemicraniectomy" (n = 20) or "no hemicraniectomy" (n = 28) group. The paired measurements of core body (T (Core)) and brain (T (Br)) temperature were recorded at 1-min intervals over 12 ± 7 days. As a surrogate measure for the extent of surface heat loss from the brain, ∆T (Core-Br) was calculated as the difference between T (Core) and T (Br) with each recording. In order to accommodate within-patient temperature correlations, mixed-model regression was used to assess the differences in ∆T (Core-Br) between those with and without hemicraniectomy, adjusted for core body temperature and diagnosis. RESULTS: A total of 295,883 temperature data pairs were collected (median [IQR] per patient: 5047 [3125-8457]). Baseline characteristics were similar for age, sex, diagnosis, incidence of sepsis, Glasgow Coma Scale score, ICU mortality, and ICU length of stay between the two groups. The mean difference in ∆T (Core-Br) was 1.29 ± 0.87°C for patients with and 0.80 ± 0.86°C for patients without hemicraniectomy (P < 0.0001). In mixed-model regression, accounting for temperature correlations within patients, hemicraniectomy and higher T (Core) were associated with greater ∆T (Core-Br) (hemicraniectomy: estimated effect = 0.60, P = 0.003; T (Core): estimated effect = 0.21, P < 0.0001). CONCLUSIONS: Hemicraniectomy is associated with modestly but significantly lower brain temperature relative to core body temperature.

Language: en