眼球 perfusion 压力不会因下体负压力而降低
Eric A Hall1,2, Richard S Whittle3,4, Ana Diaz-Artiles5,6
1Department of Biomedical Engineering, Texas A&M University, College Station, TX, USA.
NPJ microgravity
|June 8, 2024
概括
身体下部负压 (LBNP) 在模拟太空飞行期间降低眼内压 (IOP). 然而,LBNP并没有在所有测试姿势中一致降低眼球 perfusion 压力 (OPP).
科学领域:
- 空间生理学空间生理学
- 心血管研究的心血管研究.
- 眼科医生 眼科 眼科
背景情况:
- 太空飞行导致头部的液体转移,可能导致太空飞行相关的神经眼综合征 (SANS).
- 身体下部负压 (LBNP) 是一种拟议的对策,以减轻脑流体转移.
- 了解LBNP对眼睛压力的影响对于宇航员健康至关重要.
研究的目的:
- 量化LBNP对眼内压力 (IOP) 的影响,眼睛水平的平均动脉压 (MAPeye) 和眼球输液压 (OPP).
- 为了研究这些效应,无论是在0°仰卧还是15°俯仰 (HDT) 姿势中.
- 评估LBNP作为SANS相关眼部变化的对策的有效性.
主要方法:
- 24名健康受试者 (12名男性,12名女性) 接受了从0到-50毫米升级的LBNP,每次增加10毫米升.
- 测量是在0°仰卧位置和15°高垂直位置进行的.
- 在整个LBNP协议中,IOP,MAP和OPP都被持续监测.
主要成果:
- 在0°仰卧姿势和15° HDT姿势中,LBNP显著降低了IOP.
- MAPeye与卧卧的LBNP显著下降,但在HDT中保持稳定.
- 在仰卧姿势下,OPP降低,但在15°高位姿势下显著增加.
- 性别没有显著影响IOP,MAP或OPP对LBNP的反应.
结论:
- LBNP有效地降低了IOP,这是缓解SANS的潜在好处.
- LBNP对OPP的影响取决于姿势,在15° HDT时增加.
- 虽然LBNP减少了IOP,但其在所有模拟太空飞行条件中正常化OPP的整体有效性需要进一步调查.
相关概念视频
Measurement of Blood Pressure
910
Assessing blood pressure is a standard procedure executed in virtually all medical environments. The method utilized today was established over a hundred years ago by an innovative Russian doctor, Dr. Nikolai Korotkoff. The soft ticking noise, known as Korotkoff sounds, heard while taking blood pressure readings results from turbulent blood flow within the vessels. The apparatus required for this procedure includes a sphygmomanometer, a blood pressure cuff attached to a gauge, and a...
910
Disorders of the Autonomic Nervous System
625
The autonomic nervous system (ANS) is an intricate network of nerves that controls functions such as the regulation of heart rate, digestion, and blood pressure regulation. When this system malfunctions, it can lead to various disorders that affect multiple bodily functions. One common feature of many autonomic disorders is the involvement of smooth blood vessels, which play a crucial role in regulating blood flow throughout the body.
Raynaud's disease, also known as Raynaud's...
Raynaud's disease, also known as Raynaud's...
625
Pressure Relationships in Thoracic Cavity
2.2K
Breathing, otherwise known as pulmonary ventilation, is the process of air movement into and out of the lungs. The main mechanisms propelling pulmonary ventilation are atmospheric pressure (Patm), intra-pulmonary (Ppul ) or intra-alveolar pressure (Palv) within the alveoli, and intrapleural pressure (Pip) within the pleural cavity.
Breathing Mechanisms
Both intra-alveolar and intrapleural pressures rely on specific lung properties. The ability to breathe—allowing air to enter the lungs...
Breathing Mechanisms
Both intra-alveolar and intrapleural pressures rely on specific lung properties. The ability to breathe—allowing air to enter the lungs...
2.2K
Autoregulation of Blood Flow
2.3K
Autoregulation mechanisms are characterized by their inherent capacity for self-regulation without necessitating specific nervous stimulation or endocrine control. These mechanisms facilitate the adjustment of blood flow and, therefore, perfusion specific to each tissue region. This self-regulation encompasses chemical signals and myogenic controls.
Chemical Signaling in Autoregulation
Chemical signaling operates at the precapillary sphincter level, inciting either contraction or relaxation....
Chemical Signaling in Autoregulation
Chemical signaling operates at the precapillary sphincter level, inciting either contraction or relaxation....
2.3K
Sites for measruring blood pressure
1.7K
Blood pressure measurement is a fundamental clinical procedure, providing crucial data for assessing cardiovascular health. Among the various sites for this measurement, the brachial and popliteal arteries are predominantly utilized due to their accessibility and the reliability of their readings. This lesson delves into the anatomical significance, methodology, and considerations of measuring blood pressure at these locations.
The Brachial Artery: Primary Site for Blood Pressure Measurement
The Brachial Artery: Primary Site for Blood Pressure Measurement
1.7K
Capillary Exchange
4.2K
The cardiovascular system's chief role is to disseminate gases, nutrients, waste, and other substances to the body's cells. Small molecules like gases, lipids, and lipid-soluble substances directly diffuse through capillary wall endothelial cell membranes. Glucose, amino acids, and ions, including sodium, potassium, calcium, and chloride, use transporters for facilitated diffusion via membrane-specific channels. Glucose, ions, and bigger molecules may also pass through intercellular...
4.2K


