Biomaterial Database

[Countermeasuring effect of lower body negative pressure against orthostatic intolerance induced by 21 d -6 degrees head down tilt in humans]. 1999

Y J Yao, and X Y Wu, and X Q Sun, and W Y Hao, and Z L Qiao, and S Z Jiang

Department of Aerospace Medicine, The Fourth Military Medical University, Xi'an, China.

Objective. To investigate whether LBNP during 21 d -6 degrees head-down tilt (HDT) would modify orthostatic tolerance. Method. 12 healthy males, age 23.7 +/- 5.0, were exposed to -6 degrees HDT for 21 d. 6 of them received -4.0 kPa LBNP sessions for 1 h/d from 15th day to 21st day of HDT. The other 6 served as control. HUT + 75 degrees, 20 min orthostatic tolerance test were done before, on day 10 and on day 21 of HDT. Result. During HUT + 75 degrees, 20 min orthostatic tolerance test on day 10 of HDT, 5 subjects of the control group and 4 of the LBNP group presented presyncopal or syncopal signs and symptoms, the average standing time of both groups were shorter than those of the pre-HDT (p<0.05). During HUT + 75 degrees, 20 min orthostatic tolerance test on day 21 of HDT, 5 subjects of the control group and one subject of the LBNP group presented presyncopal or syncopal signs and symptoms, the average standing time of control group reduced significantly as compared with those of pre-HDT(P<0.05), also significantly shorter than those of LBNP group (P<0.05). Conclusion. The present study clearly shows that the use of LBNP could alleviate the bed rest-induced orthostatic intolerance.

UI	MeSH Term	Description	Entries
D007024	Hypotension, Orthostatic	A significant drop in BLOOD PRESSURE after assuming a standing position. Orthostatic hypotension is a finding, and defined as a 20-mm Hg decrease in systolic pressure or a 10-mm Hg decrease in diastolic pressure 3 minutes after the person has risen from supine to standing. Symptoms generally include DIZZINESS, blurred vision, and SYNCOPE.	Hypotension, Postural,Orthostatic Hypotension,Postural Hypotension
D008150	Lower Body Negative Pressure	External decompression applied to the lower body. It is used to study orthostatic intolerance and the effects of gravitation and acceleration, to produce simulated hemorrhage in physiologic research, to assess cardiovascular function, and to reduce abdominal stress during childbirth.	Abdominal Decompression,Decompression, Abdominal,LBNP
D008297	Male		Males
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D001510	Bed Rest	Confinement of an individual to bed for therapeutic or experimental reasons.	Bedrest,Bed Rests,Bedrests,Rest, Bed,Rests, Bed
D013575	Syncope	A transient loss of consciousness and postural tone caused by diminished blood flow to the brain (i.e., BRAIN ISCHEMIA). Presyncope refers to the sensation of lightheadedness and loss of strength that precedes a syncopal event or accompanies an incomplete syncope. (From Adams et al., Principles of Neurology, 6th ed, pp367-9)	Drop Attack,Fainting,Presyncope,Syncope, Postural,Syncopal Episode,Syncopal Vertigo,Syncope, Cardiogenic,Syncope, Carotid Sinus,Syncope, Convulsive,Syncope, Deglutitional,Syncope, Effort,Syncope, Hyperventilation,Syncope, Micturition,Syncope, Situational,Syncope, Stokes-Adams,Syncope, Tussive,Attack, Drop,Cardiogenic Syncope,Cardiogenic Syncopes,Carotid Sinus Syncope,Carotid Sinus Syncopes,Convulsive Syncope,Convulsive Syncopes,Deglutitional Syncope,Deglutitional Syncopes,Drop Attacks,Effort Syncope,Effort Syncopes,Episode, Syncopal,Hyperventilation Syncope,Hyperventilation Syncopes,Micturition Syncope,Micturition Syncopes,Postural Syncope,Postural Syncopes,Presyncopes,Situational Syncope,Situational Syncopes,Stokes-Adams Syncope,Stokes-Adams Syncopes,Syncopal Episodes,Syncope, Stokes Adams,Syncopes,Syncopes, Cardiogenic,Syncopes, Carotid Sinus,Syncopes, Convulsive,Syncopes, Deglutitional,Syncopes, Effort,Syncopes, Hyperventilation,Syncopes, Micturition,Syncopes, Postural,Syncopes, Situational,Syncopes, Stokes-Adams,Syncopes, Tussive,Tussive Syncope,Tussive Syncopes,Vertigo, Syncopal,Vertigos, Syncopal
D018474	Weightlessness Simulation	Condition under normal Earth gravity where the force of gravity itself is not actually altered but its influence or effect may be modified and studied. (From ASGSB Bull 1992;5(2):27)	Microgravity Simulation,Models, Weightlessness,Simulation, Microgravity,Simulation, Weightlessness,Weightlessness Model,Weightlessness Models
D018475	Head-Down Tilt	Posture while lying with the head lower than the rest of the body. Extended time in this position is associated with temporary physiologic disturbances.	Trendelenburg Position,Head Down Tilt,Position, Trendelenburg,Tilt, Head-Down
D018493	Cardiovascular Deconditioning	A change in cardiovascular function resulting in a reduction in BLOOD VOLUME, and reflex DIURESIS. It occurs frequently after actual or simulated WEIGHTLESSNESS.	Deconditioning, Cardiovascular