In April 2026, NASA’s Office of the Chief Health and Medical Officer (OCHMO) convened a working group to review updated venous thromboembolism (VTE) case information, additional data on altered blood flow in astronauts, and progress on research to mitigate clot risks during spaceflight. The group issued new evidence-based clinical practice recommendations.

This follows NASA’s initial working group formed in October 2024, after diagnosing VTEs - blood clots, for those not fluent in medical jargon - in astronauts aboard the International Space Station. Experts reviewed case data, updated Clinical Practice Guidelines, and pondered why zero gravity might make your blood do weird things.

The mission-enabling assessment aims to answer urgent questions for long-term space travel, because nothing says "exploration" like figuring out how to keep your blood from turning into jelly. The new Technical Standard outlines medical requirements and procedures to ensure crew health, because apparently floating in a tin can 250 miles up carries some occupational hazards.