Logo Medical Science Monitor

Call: +1.631.470.9640
Mon - Fri 10:00 am - 02:00 pm EST

Contact Us

Logo Medical Science Monitor Logo Medical Science Monitor Logo Medical Science Monitor

01 January 2005

Effect of lower-body negative pressure on cerebral blood fl ow velocity during 21 days head-down tilt bed rest

Xi-Qing Sun, Yong-Jie Yao, Chang-Bin Yang, Shi-Zhong Jiang, Chang-Lin Jiang, Wen-Bin Liang

Med Sci Monit 2005; 11(1): CR1-5 :: ID: 13868

Abstract

Background: The purpose of this study was to investigate cerebral blood fl ow (CBF) velocity in humans during 21 days of head-down tilt (HDT) bed rest with and without lower-body negative pressure (LBNP). Material/Methods: Twelve healthy male volunteers were exposed to –6° HDT bed rest for 21 days. Six subjects received –30 mmHg LBNP sessions for 1 h per day from the 1[sup]st[/sup] to the 7[sup]th[/sup] day and from the 15[sup]th[/sup] to the 21st day of HDT, and six others served as controls. CBF velocity was measured by use of the transcranial Doppler technique in the right middle cerebral artery before and during HDT. Results: In the control group, mean and systolic CBF velocities decreased on day 1 of HDT compared with the pre-HDT value, and dropped further on day 3 of HDT, then remained signifi cantly below the pre-HDT baseline on days 7 and 10 of HDT, and reached a minimum value on day 21 of HDT. In the LBNP group, mean and systolic CBF velocities decreased signifi cantly on day 1 of HDT compared with the pre-HDT value, and remained lowered throughout HDT. Diastolic CBF showed no signifi cant change throughout HDT in both groups. There were no signifi cant differences in these parameters between the two groups. Conclusions: The results of this study suggest that CBF velocity is reduced during 21 days of HDT, and brief daily LBNP sessions used in the fi rst and last weeks of 21-day HDT bed rest does not improve CBF velocity.

Keywords: Head-Down Tilt - adverse effects, Bed Rest, Blood Pressure, Cerebrovascular Circulation, Head-Down Tilt - adverse effects, Lower Body Negative Pressure, Ultrasonography, Doppler, Transcranial, Weightlessness

Add Comment 0 Comments

Editorial

01 November 2024 : Editorial  

Editorial: Artificial Intelligence (AI), Digital Image Analysis, and the Future of Cancer Diagnosis and Prognosis

Dinah V. Parums

DOI: 10.12659/MSM.947038

Med Sci Monit 2024; 30:e947038

0:00

In Press

Clinical Research  

Clinical Outcomes of Talus Bone Marrow Edema: Comparing Plaster Cast, Crutches, and Walking Boot Treatments

Med Sci Monit In Press; DOI: 10.12659/MSM.946072  

Review article  

Comprehensive Insights into Arecoline Hydrobromide: Pharmacology, Toxicity, and Pharmacokinetics

Med Sci Monit In Press; DOI: 10.12659/MSM.945582  

Clinical Research  

Iliac Periosteal Bone Autografting vs Talus Non-Weight-Bearing Surgery in Hepple V Talus Osteochondral Inju...

Med Sci Monit In Press; DOI: 10.12659/MSM.944912  

Clinical Research  

Impact of Different Orthodontic Appliances on Mandibular Condyle, Anterior Region of Mandibular, and Maxill...

Med Sci Monit In Press; DOI: 10.12659/MSM.946265  

Most Viewed Current Articles

17 Jan 2024 : Review article   6,335,406

Vaccination Guidelines for Pregnant Women: Addressing COVID-19 and the Omicron Variant

DOI :10.12659/MSM.942799

Med Sci Monit 2024; 30:e942799

0:00

14 Dec 2022 : Clinical Research   1,908,931

Prevalence and Variability of Allergen-Specific Immunoglobulin E in Patients with Elevated Tryptase Levels

DOI :10.12659/MSM.937990

Med Sci Monit 2022; 28:e937990

0:00

16 May 2023 : Clinical Research   695,409

Electrophysiological Testing for an Auditory Processing Disorder and Reading Performance in 54 School Stude...

DOI :10.12659/MSM.940387

Med Sci Monit 2023; 29:e940387

0:00

07 Jan 2022 : Meta-Analysis   260,542

Efficacy and Safety of Light Therapy as a Home Treatment for Motor and Non-Motor Symptoms of Parkinson Dise...

DOI :10.12659/MSM.935074

Med Sci Monit 2022; 28:e935074

Your Privacy

We use cookies to ensure the functionality of our website, to personalize content and advertising, to provide social media features, and to analyze our traffic. If you allow us to do so, we also inform our social media, advertising and analysis partners about your use of our website, You can decise for yourself which categories you you want to deny or allow. Please note that based on your settings not all functionalities of the site are available. View our privacy policy.

Medical Science Monitor eISSN: 1643-3750
Medical Science Monitor eISSN: 1643-3750