Cerebral pressure autoregulation is intact and is not influenced by hypothermia after traumatic brain injury in rats

被引:0
|
作者
Bedell, EA
DeWitt, DS
Uchida, T
Prough, DS
机构
[1] Univ Texas, Med Branch, Dept Anesthesiol, Galveston, TX 77555 USA
[2] Univ Texas, Med Branch, Off Biostat, Galveston, TX 77555 USA
关键词
autoregulation; cerebral blood flow; fluid percussion injury; hypothermia; laboratory animal models; laser Doppler flowmetry; traumatic brain injury;
D O I
暂无
中图分类号
R4 [临床医学];
学科分类号
1002 ; 100602 ;
摘要
In head-injured patients and experimental traumatic brain injury (TBI), important cerebrovascular abnormalities include decreases in cerebral blood flow (CBF) and impairment of cerebral pressure autoregulation. We evaluated CBF and pressure autoregulation after fluid percussion injury (FPI) and hypothermia in rats with the hypothesis that hypothermia would ameliorate changes in posttraumatic CBF. Male Sprague-Dawley rats, intubated and mechanically ventilated, were prepared for parasaggital FPI (1.8 atm) and laser Doppler CBF flow (LDF) measurement. The abdominal aorta was cannulated for rapid removal and reinfusion of blood. Baseline autoregulatory testing in all groups consisted of LDF measurements at normothermia and a mean arterial pressure (MAP) of 100 mm Hg, followed by randomly ordered changes of MAP to 80, 60, and 40 mm Hg. Animals were then randomized to one of five groups: normothermic control without FPI; normothermia with FPI; hypothermic control (32degreesC) without FPI; hypothermia initiated before FPI; and hypothermia initiated immediately after FPI injury. For each group, a complete, randomly ordered autoregulatory sequence was performed at 30 and 60 min after FPI or sham TBI. In a second study, rats were prepared identically, maintained at normothermic temperatures and autoregulation was tested before and after TBI using a set of randomly ordered levels of hypotension or using progressive reductions in MAP (i.e., 80, 60, 40 mm Hg) with the hypothesis that the technical manner and timing of decreasing of the blood pressure would effect CBF after TBI. Due to high acute mortality, the group in which hypothermia was induced before FPI was excluded from the analysis. At baseline, autoregulation was similar in all groups. There was no change in CBF or autoregulation in the normothermic control group at 30 and 60 min. In the other groups at 30 and 60 min, there was a similar, statistically significant decrease in absolute CBF (i.e., a decrease of 27-57% of baseline values), but pressure autoregulation was intact except at the lowest blood pressure tested at 60 min, where there was a slight improvement in the hypothermic group. Thus, in these experiments, absolute CBF decreased with hypothermia and FPI, while neither hypothermia nor FPI significantly altered autoregulation. In the second study, autoregulatory function was not different before TBI when comparing random and sequential blood pressure changes, but, when comparing the groups after TBI at the 60 mm Hg blood pressure level, CBF was significantly lower in the sequential group than in the random order group. This suggests that the mechanism of creating hypotension, whether random or sequential, significantly affects the measurement of CBF and autoregulation after TBI in rats.
引用
收藏
页码:1212 / 1222
页数:11
相关论文
共 50 条
  • [21] The effects of cerebral pressure autoregulation status and CPP levels on cerebral metabolism in pediatric traumatic brain injury
    Velle, Fartein
    Lewen, Anders
    Howells, Tim
    Hanell, Anders
    Nilsson, Pelle
    Enblad, Per
    ACTA NEUROCHIRURGICA, 2024, 166 (01)
  • [22] Cross-spectral analysis of cerebral autoregulation after mild traumatic brain injury
    Baglan Mustafayev
    Alina Mustafayeva
    Askar Bakhtiyarov
    Kuanysh Nikatov
    Neurosurgical Review, 46
  • [23] Cerebral pressure autoregulaton and management of cerebral perfusion pressure after traumatic brain injury
    Lang, EW
    ANASTHESIOLOGIE INTENSIVMEDIZIN NOTFALLMEDIZIN SCHMERZTHERAPIE, 1999, 34 : S45 - S47
  • [24] Static Autoregulation is Intact in Majority of Patients With Severe Traumatic Brain Injury
    Peterson, Eric
    Chesnut, Randall M.
    JOURNAL OF TRAUMA-INJURY INFECTION AND CRITICAL CARE, 2009, 67 (05): : 944 - 949
  • [25] Cross-spectral analysis of cerebral autoregulation after mild traumatic brain injury
    Mustafayev, Baglan
    Mustafayeva, Alina
    Bakhtiyarov, Askar
    Nikatov, Kuanysh
    NEUROSURGICAL REVIEW, 2023, 46 (01)
  • [26] Management of cerebral perfusion pressure after traumatic brain injury
    Robertson, CS
    ANESTHESIOLOGY, 2001, 95 (06) : 1513 - 1517
  • [27] CHALLENGING THE THRESHOLD OF IMPAIRED CEREBRAL AUTOREGULATION IN TRAUMATIC BRAIN INJURY
    Crippa, Ilaria Alice
    Creteur, Jacques
    Czosnyka, Marek
    Taccone, Fabio
    CRITICAL CARE MEDICINE, 2016, 44 (12)
  • [28] Hyperoxemia improves cerebral autoregulation in severe traumatic brain injury
    R Celis
    R Hlatky
    C Robertson
    Critical Care, 11 (Suppl 2):
  • [29] Cerebral Autoregulation Monitoring in Children With Mild Traumatic Brain Injury
    Tremlett, William
    Kanthimathinathan, Hari Krishnan
    PEDIATRIC CRITICAL CARE MEDICINE, 2019, 20 (07) : 694 - 695
  • [30] Cerebral Perfusion Pressure Directed-Therapy Modulates Cardiac Dysfunction After Traumatic Brain Injury to Influence Cerebral Autoregulation in Pigs
    William M. Armstead
    Monica S. Vavilala
    Neurocritical Care, 2019, 31 : 476 - 485