Temporary application of lower body positive pressure improves intracranial velocities in symptomatic acute carotid occlusion or tight stenosis: A pilot study

2021 ◽  
pp. 174749302110080
Author(s):  
Isabelle Crassard ◽  
Karine Berthet ◽  
Philippa Lavallée ◽  
Marion Houot ◽  
Didier Payen ◽  
...  
Keyword(s):  
Blood Flow ◽  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Carotid Occlusion ◽  
Positive Pressure ◽  
Lower Body ◽  
Lower Body Positive Pressure ◽  
Body Positive ◽  
Blood Flow Velocities ◽  
Flow Velocities

Background Patients with isolated cervical carotid artery occlusion not eligible to recanalization therapies but with compromised intracranial hemodynamics may be at risk of further clinical events. Apart from lying flat until spontaneous recanalization or adjustment of the collateral circulation hopefully occurs, no specific treatment is currently implemented. Improving collateral flow is an attractive option in this setting. Lower body positive pressure (LBPP) is known to result in rapid venous blood shift from the lower to the upper body part, in turn improving cardiac preload and output, and is routinely used in acute hemorrhagic shock. We report here cerebral blood flow velocities measured during LBPP in this patient population. Methods This is a retrospective analysis of the clinical, physiological, and transcranial Doppler monitoring data collected during and 15 min after LBPP in 21 consecutive patients (10 females, median age: 54 years) with recently symptomatic isolated carotid occlusion/tight stenosis (unilateral in 18) mostly due to atherosclerosis or dissection. LBPP was applied for 90 min at a median 5 days after symptom onset. Results At baseline, middle-cerebral artery velocities were markedly lower on the symptomatic, as compared to asymptomatic, side. LBPP significantly improved blood flow velocities in both the symptomatic and asymptomatic middle-cerebral artery as well as the basilar artery, which persisted 15 min after discontinuing the procedure. LBPP also resulted in mild but significant increases in mean arterial blood pressure. Conclusions LBPP improved intracranial hemodynamics downstream recently symptomatic carotid occlusion/tight stenosis as well as in the contralateral and posterior circulations, which persisted after LBPP deflation. Randomized trials should determine if this easy-to-use, noninvasive, nonpharmacologic approach has long-lasting benefits on the intracranial circulation and improves functional outcome.

Middle cerebral artery blood flow velocity in response to lower body positive pressure

2013 ◽  
pp. n/a-n/a ◽  
Author(s):  
Blake G. Perry ◽  
Zachary J. Schlader ◽  
Aaron Raman ◽  
Darryl J. Cochrane ◽  
Samuel J. E. Lucas ◽  
...  
Keyword(s):  
Blood Flow ◽  
Middle Cerebral Artery ◽  
Flow Velocity ◽  
Cerebral Artery ◽  
Blood Flow Velocity ◽  
Positive Pressure ◽  
Lower Body ◽  
Artery Blood Flow ◽  
Lower Body Positive Pressure ◽  
Body Positive

Effects of posture on peripheral vascular responses to lower body positive pressure

2007 ◽  
Vol 293 (1) ◽  
pp. H670-H676 ◽  
Author(s):  
Takeshi Nishiyasu ◽  
Shigeko Hayashida ◽  
Asami Kitano ◽  
Kei Nagashima ◽  
Masashi Ichinose
Keyword(s):  
Heart Rate ◽  
Blood Flow ◽  
Forearm Blood Flow ◽  
Positive Pressure ◽  
Upper Limbs ◽  
Lower Body ◽  
Peripheral Vascular ◽  
Vascular Responses ◽  
Lower Body Positive Pressure ◽  
Body Positive

We tested the hypothesis that peripheral vascular responses (in the lower and upper limbs) to application of lower body positive pressure (LBPP) are dependent on the posture of the subjects. We measured heart rate, stroke volume, mean arterial pressure, leg and forearm blood flow (using the Doppler ultrasound technique), and leg (LVC) and forearm (FVC) vascular conductance in 11 subjects (9 men, 2 women) without and with LBPP (25 and 50 mmHg) in supine and upright postures. Mean arterial pressure increased in proportion to increases in LBPP and was greater in supine than in upright subjects. Heart rate was unchanged when LBPP was applied to supine subjects but was reduced in upright ones. Leg blood flow and LVC were both reduced by LBPP in supine subjects [LVC: 4.8 (SD 4.0), 3.6 (SD 3.5), and 1.4 (SD 1.8) ml·min−1·mmHg−1 before LBPP and during 25 and 50 mmHg LBPP, respectively; P < 0.05] but were increased in upright ones [LVC: 2.0 (SD 1.2), 3.4 (SD 3.4), and 3.0 (SD 2.0) ml·min−1·mmHg−1, respectively; P < 0.05]. Forearm blood flow and FVC both declined when LBPP was applied to supine subjects [FVC: 1.3 (SD 0.6), 1.0 (SD 0.4), and 0.9 (SD 0.6) ml· min−1·mmHg−1, respectively; P < 0.05] but remained unchanged in upright ones [FVC: 0.7 (SD 0.4), 0.7 (SD 0.4), and 0.6 (SD 0.5) ml·min−1·mmHg−1, respectively]. Together, these findings indicate that the leg vascular response to application of LBPP is posture dependent and that the response differs in the lower and upper limbs when subjects assume an upright posture.

Ambulation in simulated fractional gravity using lower body positive pressure: cardiovascular safety and gait analyses

2006 ◽  
Vol 101 (3) ◽  
pp. 771-777 ◽  
Author(s):  
Adnan Cutuk ◽  
Eli R. Groppo ◽  
Edward J. Quigley ◽  
Klane W. White ◽  
Robert A. Pedowitz ◽  
...  
Keyword(s):  
Heart Rate ◽  
Blood Flow ◽  
Ambient Pressure ◽  
Cardiovascular Responses ◽  
Microvascular Blood Flow ◽  
Positive Pressure ◽  
Lower Body ◽  
Lower Body Positive Pressure ◽  
Body Positive ◽  
Gait Mechanics

The purpose of this study is to assess cardiovascular responses to lower body positive pressure (LBPP) and to examine the effects of LBPP unloading on gait mechanics during treadmill ambulation. We hypothesized that LBPP allows comfortable unloading of the body with minimal impact on the cardiovascular system and gait parameters. Fifteen healthy male and female subjects (22–55 yr) volunteered for the study. Nine underwent noninvasive cardiovascular studies while standing and ambulating upright in LBPP, and six completed a gait analysis protocol. During stance, heart rate decreased significantly from 83 ± 3 beats/min in ambient pressure to 73 ± 3 beats/min at 50 mmHg LBPP ( P < 0.05). During ambulation in LBPP at 3 mph (1.34 m/s), heart rate decreased significantly from 99 ± 4 beats/min in ambient pressure to 84 ± 2 beats/min at 50 mmHg LBPP ( P < 0.009). Blood pressure, brain oxygenation, blood flow velocity through the middle cerebral artery, and head skin microvascular blood flow did not change significantly with LBPP. As allowed by LBPP, ambulating at 60 and 20% body weight decreased ground reaction force ( P < 0.05), whereas knee and ankle sagittal ranges of motion remained unaffected. In conclusion, ambulating in LBPP has no adverse impact on the systemic and head cardiovascular parameters while producing significant unweighting and minimal alterations in gait kinematics. Therefore, ambulating within LBPP is potentially a new and safe rehabilitation tool for patients to reduce loads on lower body musculoskeletal structures while preserving gait mechanics.

Blood Flow Velocities in Middle Cerebral Artery Branches After Subarachnoid Hemorrhage

2000 ◽  
Vol 10 (3) ◽  
pp. 157-161 ◽  
Author(s):  
Kay Mursch ◽  
Ahmad Bransi ◽  
Hartmut Vatter ◽  
Gregor Herrendorf ◽  
Julianne Behnke-Mursch ◽  
...  
Keyword(s):  
Blood Flow ◽  
Subarachnoid Hemorrhage ◽  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Blood Flow Velocities ◽  
Flow Velocities

scholarly journals Lower-body positive pressure diminishes surface blood flow reactivity during treadmill walking

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Junichi Tajino ◽  
Akira Ito ◽  
Yusuke Torii ◽  
Koji Tsuchimoto ◽  
Hirotaka Iijima ◽  
...  
Keyword(s):  
Blood Flow ◽  
Applied Pressure ◽  
Treadmill Walking ◽  
Positive Pressure ◽  
Lower Body ◽  
Rehabilitation Treatment ◽  
Blood Flows ◽  
Lower Body Positive Pressure ◽  
Orthopedic Rehabilitation ◽  
Body Positive

Abstract Objective The purpose of this study was to determine the effects of the lower-body positive pressure on surface blood flow during standing still and treadmill walking to explore cardiovascular safety for application to rehabilitation treatment. Thirteen healthy volunteers participated in the experiment and surface blood flows were measured in the forehead, thigh, calf, and the top of the foot during standing still and walking under various pressure conditions (0 kPa, 5 kPa, and 6.7 kPa). Results Lower-body positive pressure decreased the blood flow in the forehead and the thigh during walking (p < .05 for each), whereas an increasing trend in blood flow was observed during standing still (p < .05). Furthermore, in the forehead and thigh, the extent of blood flow increase at the onset of walking was found to decrease in accordance with the applied pressure (p < .01 for each). These findings suggest that during walking, lower-body positive pressure modulates the blood flow, which implies safeness of this novel apparatus for use during orthopedic rehabilitation treatment.

Sign in / Sign up

Export Citation Format

Share Document