Nav: Home

Long duration weightlessness in space induces a blood shift

January 14, 2015

In a study published today in The Journal of Physiology, researchers found that in space, the shift of blood and fluid from the lower to the upper body caused by weightlessness is much higher and the blood pressure much lower than previously thought.

Researchers measured the volume of blood ejected by the heart into the blood vessels and monitored the blood pressure in eight astronauts aged between 45-53 years during a 24 h period with portable equipment. Recordings were taken before, during and after 3-6 months of spaceflight. A blood sample was also collected to analyse the nervous regulation of the cardiovascular system.

The team of researchers found that the shift of blood and fluid from the lower to the upper body caused by weightlessness was much higher than previously thought. The blood volume burden to the heart was also more than expected despite the heart rate remaining the same. At the same time, blood pressure was considerably reduced by 10 mmHg, which corresponds to the effect of normal blood pressure medication against high blood pressure.

Dr Peter Norsk, lead author of the study says: "The discovery is important because during long duration missions, the blood volume burden to the heart could constitute a health problem during future long duration missions. We know that some astronauts experience vision problems some months into spaceflight and this may in fact be caused by the augmented fluid and blood volume shift to the upper body.

Although the blood volume burden to the heart is higher than expected, blood pressure is lower because the blood vessels are more relaxed (dilated). This is actually good for the body and the blood vessels.Thus, there are one or more spaceflight factors leading to these changes, which haven't been identified yet. In the future, the spaceflight factors that induce the fluid shifts and relaxation (dilatation) of the blood vessels should be identified."
-end-
Notes to Editors

1. Full paper title: Norsk P, Asmar A, Damgaard M & Christensen NJ (2015) Fluid Shifts, Vasodilatation and Ambulatory Blood Pressure Reduction during Long Duration Spaceflight. J Physiol DOI: 10.1113/jphysiol.2014.284869

2. The Journal of Physiology publishes advances in physiology that increase our understanding of how our bodies function in health and disease. http://.jp.physoc.org

3. The Physiological Society brings together over 3000 scientists from over 60 countries and promotes physiology with the public and parliament alike. It supports physiologists by organising world-class conferences and offering grants for research and also publishes the latest developments in the field in its two leading scientific journals, The Journal of Physiology and Experimental Physiology. http://www.physoc.org

Wiley

Related Blood Pressure Articles:

Do you really have high blood pressure?
A study by researchers at the University of Montreal Hospital Research Centre (CRCHUM) shows that more than half of family doctors in Canada are still using manual devices to measure blood pressure, a dated technology that often leads to misdiagnosis.
Why do we develop high blood pressure?
Abnormally high blood pressure, or hypertension, may be related to changes in brain activity and blood flow early in life.
For some, high blood pressure associated with better survival
Patients with both type 2 diabetes and acute heart failure face a significantly lower risk of death but a higher risk of heart failure-related hospitalizations if they had high systolic blood pressure on discharge from the hospital compared to those with normal blood pressure, according to a study scheduled for presentation at the American College of Cardiology's 66th Annual Scientific Session.
$9.4 million grant helps scientists explore how cell death from high blood pressure fuels even higher pressure
It's been known for decades that a bacterial infection can raise your blood pressure short term, but now scientists are putting together the pieces of how our own dying cells can fuel chronically high, destructive pressure.
Blood pressure diet improves gout blood marker
A diet rich in fruits, vegetables, low-fat dairy and reduced in fats and saturated fats (the DASH diet), designed decades ago to reduce high blood pressure, also appears to significantly lower uric acid, the causative agent of gout.
New tool to improve blood pressure measurement
Oxford University researchers have developed a prediction model that uses three separate blood pressure readings taken in a single consultation and basic patient characteristics to give an adjusted blood pressure reading that is significantly more accurate than existing models for identifying hypertension.
Blood vessels sprout under pressure
It is blood pressure that drives the opening of small capillaries during angiogenesis.
Better blood pressure control -- by mobile phone
An interactive web system with the help of your mobile phone can be an effective tool for better blood pressure control.
Time to reassess blood-pressure goals
High blood pressure or hypertension is a major health problem that affects more than 70 million people in the US, and over one billion worldwide.
With help from pharmacists, better blood pressure costs $22
A pharmacist-physician collaboration in primary-care offices effectively and inexpensively improved patients' high blood pressure.

Related Blood Pressure Reading:

The High Blood Pressure Hoax
by Sherry A. Rogers (Author)

Blood Pressure Down: The 10-Step Plan to Lower Your Blood Pressure in 4 Weeks--Without Prescription Drugs
by Janet Bond Brill PhD RD (Author)

The Magnesium Solution for High Blood Pressure (The Square One Health Guides)
by Jay S. Cohen (Author)

Thirty Days to Natural Blood Pressure Control: The No Pressure Solution
by MPH, David DeRose MD (Author), MPH, Greg Steinke MD (Author), Trudie Li FNP (Author), Clifford Goldstein (Editor)

Lower Your Blood Pressure: A 21-Day DASH Diet Meal Plan to Decrease Blood Pressure Naturally
by Jennifer Koslo PhD RDN CSSD (Author)

Reversing Hypertension: A Vital New Program to Prevent, Treat, and Reduce High Blood Pressure
by Julian Whitaker (Author)

Blood Pressure Log Book: Daily Personal Record and your health Monitor Tracking Numbers of Blood Pressure, Heart Rate, Weight, Temperature, Notes With ... Monitoring Health Diary Notebook) (Volume 1)
by Holly Journals (Author)

Blood Pressure Solution: The Path to Naturally Lower and Control your Blood Pressure, Without Medication
by Margaret Schmitt (Author)

Diabetes Journal and Blood Pressure Log Book: Daily Blood Pressure and Blood Sugar Levels, Keep Track Monitoring for Gestational, Tracking BP, ... and Blood Pressure Log Book) (Volume 2)
by Mary W. Publishing (Author)

Blood Pressure: 40 Super-food that will naturally lower your blood pressure
by Arnold Yates (Author)

Best Science Podcasts 2018

We have hand picked the best science podcasts for 2018. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

The Story Behind The Numbers
Is life today better than ever before? Does the data bear that out? This hour, TED speakers explore the stories we tell with numbers — and whether those stories portray the full picture. Guests include psychologist Steven Pinker, economists Tyler Cowen and Michael Green, journalist Hanna Rosin, and environmental activist Paul Gilding.
Now Playing: Science for the People

#486 Volcanoes
This week we're talking volcanoes. Because there are few things that fascinate us more than the amazing, unstoppable power of an erupting volcano. First, Jessica Johnson takes us through the latest activity from the Kilauea volcano in Hawaii to help us understand what's happening with this headline-grabbing volcano. And Janine Krippner joins us to highlight some of the lesser-known volcanoes that can be found in the USA, the different kinds of eruptions we might one day see at them, and how damaging they have the potential to be. Related links: Kilauea status report at USGS A beginner's guide to Hawaii's otherworldly...