Influence of head-over-body and body-over-head posture on craniospinal, vascular, and abdominal pressures in an acute ovine in-vivo model

Fluids and Barriers of the CNS

Research

Margarete Arras¹  Nina Eva Trimmel¹  Miriam Weisskopf¹  Anthony Podgoršak²  Fabian Flürenbrock²  Marianne Schmid Daners²  Markus Florian Oertel³ 

[1] Center for Surgical Research, University Hospital Zurich, University of Zurich, Zurich, Switzerland;Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland;Department of Neurosurgery, University Hospital Zurich, University of Zurich, Zurich, Switzerland;

关键词: Arterial blood pressure;    Cerebrospinal fluid;    Hydrocephalus;    Intracranial pressure;    Sheep model;    Transfer function;    Tilt testing;   

DOI  :  10.1186/s12987-023-00458-9

 received in 2023-01-25, accepted in 2023-07-13,  发布年份 2023

来源: Springer

【 摘 要 】

IntroductionOptimal shunt-based hydrocephalus treatments are heavily influenced by dynamic pressure behaviors between proximal and distal ends of shunt catheters. Posture-dependent craniospinal, arterial, venous, and abdominal dynamics thereby play an essential role.MethodsAn in-vivo ovine trial (n = 6) was conducted to evaluate communication between craniospinal, arterial, venous, and abdominal dynamics. Tilt-testing was performed between –13° and + 13° at 10-min intervals starting and ending at 0° prone position. Mean pressure, pulse pressure, and Pearson correlation (r) to the respective angle were calculated. Correlations are defined as strong: |r|≥ 0.7, mild: 0.3 <|r|< 0.7, and weak: |r|≤ 0.3. Transfer functions (TFs) between the arterial and adjacent compartments were derived.ResultsStrong correlations were observed between posture and: mean carotid/femoral arterial (r = − 0.97, r = − 0.87), intracranial, intrathecal (r = − 0.98, r = 0.94), jugular (r = − 0.95), abdominal cranial, dorsal, caudal, and intravesical pressure (r = − 0.83, r = 0.84, r = − 0.73, r = 0.99) while mildly positive correlation exists between tilt and central venous pressure (r = 0.65). Only dorsal abdominal pulse pressure yielded a significant correlation to tilt (r = 0.21). TFs followed general lowpass behaviors with resonant peaks at 4.2 ± 0.4 and 11.5 ± 1.5 Hz followed by a mean roll-off of − 15.9 ± 6.0 dB/decade.ConclusionsTilt-tests with multi-compartmental recordings help elucidate craniospinal, arterial, venous, and abdominal dynamics, which is essential to optimize shunt-based therapy. Results motivate hydrostatic influences on mean pressure, with all pressures correlating to posture, with little influence on pulse pressure. TF results quantify the craniospinal, arterial, venous, and abdominal compartments as compliant systems and help pave the road for better quantitative models of the interaction between the craniospinal and adjacent spaces.

【 授权许可】

CC BY   
© The Author(s) 2023

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