ArticlePhysiological reports2021
Proposed mechanism for reduced jugular vein flow in microgravity.
Article in Physiological reports, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers.
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Who cites it
14 citing papers in PubMed, 25 citations in OpenAlex.
- Spaceflight-associated neuro-ocular syndrome (SANS): expert consensus on diagnosis and management.Eye (London, England) · 2026Review
- A computational model for retinal haemodynamics under gravitational and postural variations.The Journal of physiology · 2026Article
- Neck-vein thrombosis during spaceflight.British journal of clinical pharmacology · 2026Review
- [Risks, mechanisms, and prevention strategies for cerebrovascular diseases in lunar astronauts under deep].Zhong nan da xue xue bao. Yi xue ban = Journal of Central South University. Medical sciences · 2025Review
- Spatial and Temporal Changes in Choroid Morphology Associated With Long-Duration Spaceflight.Investigative ophthalmology & visual science · 2025Article
- Spaceflight Associated Neuro-ocular Syndrome (SANS) and its countermeasures.Progress in retinal and eye research · 2025Review
- Numerical analysis of blood flow in the abdominal aorta under simulated weightlessness and earth conditions.Scientific reports · 2024Article
- Modeling the impact of thoracic pressure on intracranial pressure.NPJ microgravity · 2024Article
- Linking cerebral hemodynamics and ocular microgravity-induced alterations through an in silico-in vivo head-down tilt framework.NPJ microgravity · 2024Article
- Gravitational effects on carotid and jugular characteristics in graded head-up and head-down tilt.Journal of applied physiology (Bethesda, Md. : 1985) · 2023Article
- Why central venous pressure falls below supine levels in weightlessness.Journal of applied physiology (Bethesda, Md. : 1985) · 2022Article
- A theory for why the spaceflight-associated neuro-ocular syndrome develops.Journal of applied physiology (Bethesda, Md. : 1985) · 2022Article
- Going against the flow: are venous thromboembolism and impaired cerebral drainage critical risks for spaceflight?Journal of applied physiology (Bethesda, Md. : 1985) · 2022Article
- Does Long-Duration Exposure to Microgravity Lead to Dysregulation of the Brain and Ocular Glymphatic Systems?Eye and brain · 2022Review
Corrections and comments
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Authors and funding
10 authors at 5 institutions in 1 country.
Funding
Abstract
Internal jugular flow is reduced in space compared with supine values, which can be associated with internal jugular vein (IJV) thrombosis. The mechanism is unknown but important to understand to prevent potentially serious vein thromboses on long duration flights. We used a novel, microgravity-focused numerical model of the cranial vascular circulation to develop hypotheses for the reduced flow. This model includes the effects of removing hydrostatic gradients and tissue compressive forces - unique effects of weightlessness. The IJV in the model incorporates sensitivity to transmural pressure across the vein, which can dramatically affect resistance and flow in the vein. The model predicts reduced IJV flow in space. Although tissue weight in the neck is reduced in weightlessness, increasing transmural pressure, this is more than offset by the reduction in venous pressure produced by the loss of hydrostatic gradients and tissue pressures throughout the body. This results in a negative transmural pressure and increased IJV resistance. Unlike the IJV, the walls of the vertebral plexus are rigid; transmural pressure does not affect its resistance and so its flow increases in microgravity. This overall result is supported by spaceflight measurements, showing reduced IJV area inflight compared with supine values preflight. Significantly, this hypothesis suggests that interventions that further decrease internal IJV pressure (such as lower body negative pressure), which are not assisted by other drainage mechanisms (e.g. gravity), might lead to stagnant flow or IJV collapse with reduced flow, which could increase rather than decrease the risk of venous thrombosis.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.