NASA expert reviews detail health risk recommendations

NASA expert reviews have set out recommendations on spaceflight health risks. The work addresses venous thromboembolism and patent foramen ovale in connection with decompression sickness.

The effort was meant to bring together experts to examine recent data, and its recommendations were designed to incorporate earlier results.

The recommendations emphasize steps to reduce risk, including PFO closure, which is identified as one risk-mitigation intervention.

The PFO assessment related to DCS is dated 2024-09, and the NASA working group on venous thromboembolism in spaceflight is dated 2026-04. The review considered an updated DCS prevention standard in NASA-STD-3001 Volume 2.

Ground-based studies should not exclude participants only because of LVGE, while protocols should weigh subject safety against how representative the population is. Participants must receive full information about LVGE status and related risks.

PFO is not viewed as a major risk factor for forming VTE or for complications from an embolism, and no changes to astronaut selection criteria are recommended concerning PFOs and VTE.

Bubble grades have no established link to altitude DCS risk, and bubble scores have uncertain predictive value, though reducing bubbles is considered desirable. A small PFO is not seen as a significant risk, while opinions are mixed on whether closure or screening reduces VGE risk for large PFOs.

Universal screening or exclusion is not recommended for astronauts with large PFOs; instead, assessed crew members should be told their status and offered closure when a large PFO is found. Risk mitigation is emphasized through protocol design and continued data collection.

Clinical guidance is required for medication use before EVAs, and protocols must address aspirin for DCS prevention and pain relief. Guidance is also needed for analgesics before and after EVAs because they may hide DCS symptoms.

For readers tracking the lunar industry, these facts show NASA's approach to crew-health issues that can affect astronaut selection, ground-study design, and EVA operations. NASA is also the organization associated with Artemis, making its human-spaceflight standards relevant to lunar program tracking.