Regional cerebral pulsatile hemodynamics during isocapnic and poikilocapnic hyperthermia in young men.

• Tác giả: Philip N Ainslie, Anthony R Bain, Brooke R Shepley, Spencer J Skaper, Kurt J Smith, Ibrahim Amr Wafai
• Ngôn ngữ: eng
• Thông tin xuất bản: United States : Physiological reports , 2025
• Bộ sưu tập: NCBI
• ID: 646069

Tóm tắt

 Hyperthermia is known to induce hypocapnia-driven reductions in cerebral blood flow
  however, it is unknown if it causes changes in hemodynamic pulsatility that negatively influence cerebrovascular function. This retrospective analysis aimed to assess cerebrovascular hemodynamic pulsatile buffering (damping factor
  DFi) during poikilocapnic (HT) and isocapnic (HT-C) hyperthermia. We hypothesized that HT would reduce cerebral DFi, while HT-C would attenuate the reduction in DFi by limiting increases in resistance. Ten healthy males were passively heated +2°C from normothermia (BL). Blood flow through the internal carotid artery (ICA) and vertebral artery (VA) was measured using vascular ultrasound. Blood velocity through the middle cerebral artery (MCA) and the posterior cerebral artery (PCA) was measured using transcranial ultrasound. DFi was calculated as the ratio of proximal to distal pulsatility index (PI): Anterior cerebral DFi = PI