scholarly journals A comparison of different modes of pneumatic compression on muscle tissue oxygenation: An intraparticipant, randomised, controlled volunteer study

2019 ◽  
Vol 47 (1) ◽  
pp. 23-31 ◽  
Author(s):  
Sanat K Nandwana ◽  
Kwok M Ho

Intermittent pneumatic compression (IPC) to the lower limbs is widely used as a mechanical means to prevent deep vein thrombosis in hospitalised patients. Due to a theoretical concern about impairing blood flow, thromboembolic-deterrent stockings and IPC are considered contraindicated for patients with peripheral vascular diseases by some clinicians. This study assessed whether IPC would alter peripheral limb muscle tissue oxygenation (StO2), and whether such changes were different during 10 minutes of sequential and single-compartment compressions. Twenty volunteers were randomised to have their left or right arm treated with a sequential or single-compartment IPC for 10 minutes, using the contralateral arm without compression as an intraparticipant control. After a five-minute wash-out period, the procedure was repeated on the same arm using the alternative mode of IPC. Both hands’ thenar muscles StO2 was monitored every two minutes for 10 minutes using the same near-infrared spectroscopy StO2 monitor. Both sequential (3.5%, 95% confidence intervals (CI) 2.7–4.2; p < 0.001) and single-compartment IPC (1.6%, 95% CI 0.4–2.8; p = 0.039) significantly increased muscle StO2 within 10 minutes compared to no compression; and the increments were higher during sequential compressions compared to during single-compartment compressions (2.1%, 95% CI 0.7–3.5; p = 0.023). This mechanistic study showed that both modes of IPC increased upper limb muscle StO2 compared to no compression, but the StO2 increments were higher with the multiple-chamber sequential compressions mode. Contrary to the theoretical concern that IPC may impair peripheral limb tissue oxygenation, our results showed that IPC actually increases oxygenation of the peripheral limb muscles, especially during the sequential compressions mode.

2021 ◽  
Vol 12 ◽  
Author(s):  
Janne Bouten ◽  
Sander De Bock ◽  
Gil Bourgois ◽  
Sarah de Jager ◽  
Jasmien Dumortier ◽  
...  

Introduction: Acute apnea evokes bradycardia and peripheral vasoconstriction in order to conserve oxygen, which is more pronounced with face immersion. This response is contrary to the tachycardia and increased blood flow to muscle tissue related to the higher oxygen consumption during exercise. The aim of this study was to investigate cardiovascular and metabolic responses of dynamic dry apnea (DRA) and face immersed apnea (FIA).Methods: Ten female volunteers (17.1 ± 0.6 years old) naive to breath-hold-related sports, performed a series of seven dynamic 30 s breath-holds while cycling at 25% of their peak power output. This was performed in two separate conditions in a randomized order: FIA (15°C) and DRA. Heart rate and muscle tissue oxygenation through near-infrared spectroscopy were continuously measured to determine oxygenated (m[O2Hb]) and deoxygenated hemoglobin concentration (m[HHb]) and tissue oxygenation index (mTOI). Capillary blood lactate was measured 1 min after the first, third, fifth, and seventh breath-hold.Results: Average duration of the seven breath-holds did not differ between conditions (25.3 s ± 1.4 s, p = 0.231). The apnea-induced bradycardia was stronger with FIA (from 134 ± 4 to 85 ± 3 bpm) than DRA (from 134 ± 4 to 100 ± 5 bpm, p &lt; 0.001). mTOI decreased significantly from 69.9 ± 0.9% to 63.0 ± 1.3% (p &lt; 0.001) which is reflected in a steady decrease in m[O2Hb] (p &lt; 0.001) and concomitant increase in m[HHb] (p = 0.001). However, this was similar in both conditions (0.121 &lt; p &lt; 0.542). Lactate was lower after the first apnea with FIA compared to DRA (p = 0.038), while no differences were observed in the other breath-holds.Conclusion: Our data show strong decreases in heart rate and muscle tissue oxygenation during dynamic apneas. A stronger bradycardia was observed in FIA, while muscle oxygenation was not different, suggesting that FIA did not influence muscle oxygenation. An order of mechanisms was observed in which, after an initial tachycardia, heart rate starts to decrease after muscle tissue deoxygenation occurs, suggesting a role of peripheral vasoconstriction in the apnea-induced bradycardia. The apnea-induced increase in lactate was lower in FIA during the first apnea, probably caused by the stronger bradycardia.


1995 ◽  
Author(s):  
Benoit Vallet ◽  
Jacques Mangalaboyi ◽  
Patrick Menager ◽  
Scott E. Curtis ◽  
Claude Chopin ◽  
...  

2021 ◽  
Vol 12 ◽  
Author(s):  
Jui-Lin Fan ◽  
Tian Yi Wu ◽  
Andrew T. Lovering ◽  
Liya Nan ◽  
Wang Liang Bang ◽  
...  

The Tibetans’ better aerobic exercise capacity at altitude remains ill-understood. We tested the hypothesis that Tibetans display better muscle and brain tissue oxygenation during exercise in hypoxia. Using near-infrared spectrometry (NIRS) to provide indices of tissue oxygenation, we measured oxy- and deoxy-hemoglobin ([O2Hb] and [HHb], respectively) responses of the vastus lateralis muscle and the right prefrontal cortex in ten Han Chinese and ten Tibetans during incremental cycling to exhaustion in a pressure-regulated chamber at simulated sea-level (air at 1 atm: normobaric normoxia) and 5,000 m (air at 0.5 atm: hypobaric hypoxia). Hypoxia reduced aerobic capacity by ∼22% in both groups (d= 0.8,p&lt; 0.001 vs. normoxia), while Tibetans consistently outperformed their Han Chinese counterpart by ∼32% in normoxia and hypoxia (d= 1.0,p= 0.008). We found cerebral [O2Hb] was higher in Tibetans at normoxic maximal effort compared Han (p= 0.001), while muscle [O2Hb] was not different (p= 0.240). Hypoxic exercise lowered muscle [O2Hb] in Tibetans by a greater extent than in Han (interaction effect:p&lt; 0.001 vs. normoxic exercise). Muscle [O2Hb] was lower in Tibetans when compared to Han during hypoxic exercise (d= 0.9,p= 0.003), but not during normoxic exercise (d= 0.4,p= 0.240). Muscle [HHb] was not different between the two groups during normoxic and hypoxic exercise (p= 0.778). Compared to Han, our findings revealed a higher brain tissue oxygenation in Tibetans during maximal exercise in normoxia, but lower muscle tissue oxygenation during exercise in hypoxia. This would suggest that the Tibetans privileged oxygenation of the brain at the expense of that of the muscle.


2010 ◽  
Vol 36 (11) ◽  
pp. 1882-1889 ◽  
Author(s):  
Jean-François Georger ◽  
Olfa Hamzaoui ◽  
Anis Chaari ◽  
Julien Maizel ◽  
Christian Richard ◽  
...  

2010 ◽  
Vol 30 (3) ◽  
pp. 463-471 ◽  
Author(s):  
Sam J. Thomson ◽  
Matthew L. Cowan ◽  
Daniel M. Forton ◽  
Sarah J. Clark ◽  
Saif Musa ◽  
...  

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