Effects of hyperoxia on the dynamics of skeletal muscle oxygenation at the onset of heavy-intensity exercise in patients with COPD

Siqueira, Ana Cristina B.; Borghi‐Silva, Audrey; Bravo, Daniela M.; Ferreira, Eloara Vieira Machado; Chiappa, Gaspar R.; Neder, J. Alberto

doi:10.1016/j.resp.2010.04.020

Cited by 19 publications

(12 citation statements)

References 35 publications

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“…4). These results extend those reported previously during high-intensity whole body exercise (8,10,11,46) Note that COPD patients demonstrated higher ⌬deoxy-[Hb/Mb]/torque values (i.e., increased fractional O2 extraction to produce torque) relative to control subjects and as a function of NMES intensity. P Ͻ 0.05: *intragroup difference vs. the previous value; †intergroup differences at a given NMES intensity.…”

Section: Discussionsupporting

confidence: 89%

Oxygen delivery-utilization mismatch in contracting locomotor muscle in COPD: peripheral factors

Medeiros

Fernandes

Azevedo

et al. 2015

American Journal of Physiology-Regulatory, Integrative and Comp

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Central cardiorespiratory and gas exchange limitations imposed by chronic obstructive pulmonary disease (COPD) impair ambulatory skeletal muscle oxygenation during whole body exercise. This investigation tested the hypothesis that peripheral factors per se contribute to impaired contracting lower limb muscle oxygenation in COPD patients. Submaximal neuromuscular electrical stimulation (NMES; 30, 40, and 50 mA at 50 Hz) of the quadriceps femoris was employed to evaluate contracting skeletal muscle oxygenation while minimizing the influence of COPD-related central cardiorespiratory constraints. Fractional O₂ extraction was estimated by near-infrared spectroscopy (deoxyhemoglobin/myoglobin concentration; deoxy-[Hb/Mb]), and torque output was measured by isokinetic dynamometry in 15 nonhypoxemic patients with moderate-to-severe COPD (SpO2 = 94 ± 2%; FEV₁ = 46.4 ± 10.1%; GOLD II and III) and in 10 age- and gender-matched sedentary controls. COPD patients had lower leg muscle mass than controls (LMM = 8.0 ± 0.7 kg vs. 8.9 ± 1.0 kg, respectively; P < 0.05) and produced relatively lower absolute and LMM-normalized torque across the range of NMES intensities (P < 0.05 for all). Despite producing less torque, COPD patients had similar deoxy-[Hb/Mb] amplitudes at 30 and 40 mA (P > 0.05 for both) and higher deoxy-[Hb/Mb] amplitude at 50 mA (P < 0.05). Further analysis indicated that COPD patients required greater fractional O₂ extraction to produce torque (i.e., ↑Δdeoxy-[Hb/Mb]/torque) relative to controls (P < 0.05 for 40 and 50 mA) and as a function of NMES intensity (P < 0.05 for all). The present data obtained during submaximal NMES of small muscle mass indicate that peripheral abnormalities contribute mechanistically to impaired contracting skeletal muscle oxygenation in nonhypoxemic, moderate-to-severe COPD patients.

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Section: Discussionsupporting

confidence: 89%

Oxygen delivery-utilization mismatch in contracting locomotor muscle in COPD: peripheral factors

Medeiros

Fernandes

Azevedo

et al. 2015

American Journal of Physiology-Regulatory, Integrative and Comp

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“…This overshoot in deoxygenation has also been reported in patients with type 2 diabetes (5), pulmonary arterial hypertension (3), and chronic obstructive pulmonary disease (50), as well as in young men following prolonged bed rest (40). Whether this overshoot in muscle deoxygenation presents a limitation to O 2 diffusion between the capillary and mitochondrion or whether it contributes to slowing V O 2 kinetics in CHF is unclear.…”

mentioning

confidence: 81%

The intramuscular contribution to the slow oxygen uptake kinetics during exercise in chronic heart failure is related to the severity of the condition

Bowen

Cannon²,

Murgatroyd³

et al. 2012

Journal of Applied Physiology

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Bowen TS, Cannon DT, Murgatroyd SR, Birch KM, Witte KK, Rossiter HB. The intramuscular contribution to the slow oxygen uptake kinetics during exercise in chronic heart failure is related to the severity of the condition. J Appl Physiol 112: 378 -387, 2012. First published October 27, 2011 doi:10.1152/japplphysiol.00779.2011The mechanism for slow pulmonary O2 uptake (V O2) kinetics in patients with chronic heart failure (CHF) is unclear but may be due to limitations in the intramuscular control of O2 utilization or O2 delivery. Recent evidence of a transient overshoot in microvascular deoxygenation supports the latter. Prior (or warm-up) exercise can increase O2 delivery in healthy individuals. We therefore aimed to determine whether prior exercise could increase muscle oxygenation and speed V O2 kinetics during exercise in CHF. Fifteen men with CHF (New York Heart Association I-III) due to left ventricular systolic dysfunction performed two 6-min moderate-intensity exercise transitions (bouts 1 and 2, separated by 6 min of rest) from rest to 90% of lactate threshold on a cycle ergometer. V O2 was measured using a turbine and a mass spectrometer, and muscle tissue oxygenation index (TOI) was determined by near-infrared spectroscopy. Prior exercise increased resting TOI by 5.3 Ϯ 2.4% (P ϭ 0.001), attenuated the deoxygenation overshoot (Ϫ3.9 Ϯ 3.6 vs. Ϫ2.0 Ϯ 1.4%, P ϭ 0.011), and speeded the V O2 time constant (V O2; 49 Ϯ 19 vs. 41 Ϯ 16 s, P ϭ 0.003). Resting TOI was correlated to V O2 before (R 2 ϭ 0.51, P ϭ 0.014) and after (R 2 ϭ 0.36, P ϭ 0.051) warm-up exercise. However, the mean response time of TOI was speeded between bouts in half of the patients (26 Ϯ 8 vs. 20 Ϯ 8 s) and slowed in the remainder (32 Ϯ 11 vs. 44 Ϯ 16 s), the latter group having worse New York Heart Association scores (P ϭ 0.042) and slower V O2 kinetics (P ϭ 0.001). These data indicate that prior moderate-intensity exercise improves muscle oxygenation and speeds V O2 kinetics in CHF. The most severely limited patients, however, appear to have an intramuscular pathology that limits V O2 kinetics during moderate exercise. muscle oxygenation; near-infrared spectroscopy; prior exercise CHRONIC HEART FAILURE (CHF) is a syndrome characterized by exercise intolerance due to breathlessness and fatigue in the presence of cardiac dysfunction. A treadmill or cycle-based symptom-limited peak exercise test, with pulmonary gas exchange measurement to determine peak O 2 uptake (V O 2peak ), is the most widely used measure of physiological limitation in CHF and provides objective information on aerobic capacity, symptomatology, and prognosis (35). However, activities of daily living rarely occur at or around V O 2peak . Therefore, the rate at which aerobic energy transfer adapts [O 2 uptake (V O 2 ) kinetics] to changing energy demands may provide an assessment that is more appropriate to daily exercise limitations in CHF than traditional measures (1, 52). Accordingly, initial evidence indicates that V O 2 kinetics are more strongly correlated to disease s...

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“…Such studies have investigated the impact of the pulmonary system limitations on locomotor muscle fatigue in patients with COPD (490)(491)(492). Collectively, these studies (491)(492)(493) have shown that respiratory muscle unloading (via oxygen and/or heliox breathing, bronchodilation, and proportional-assist ventilation) improves leg muscle oxygen availability during exercise in patients with COPD. Recently, NIRS has been used in combination with the light-absorbing tracer indocyanine green dye to quantify regional blood flow in muscle and connective tissue during dynamic exercise in patients with COPD (352).…”

Section: Assessment Of Muscle Oxygenation Using Near-infrared and Magmentioning

confidence: 99%

An Official American Thoracic Society/European Respiratory Society Statement: Update on Limb Muscle Dysfunction in Chronic Obstructive Pulmonary Disease

Maltais¹,

Decramer²,

Casaburi³

et al. 2014

Am J Respir Crit Care Med

887

1,033

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Effects of hyperoxia on the dynamics of skeletal muscle oxygenation at the onset of heavy-intensity exercise in patients with COPD

Cited by 19 publications

References 35 publications

Oxygen delivery-utilization mismatch in contracting locomotor muscle in COPD: peripheral factors

Oxygen delivery-utilization mismatch in contracting locomotor muscle in COPD: peripheral factors

The intramuscular contribution to the slow oxygen uptake kinetics during exercise in chronic heart failure is related to the severity of the condition

An Official American Thoracic Society/European Respiratory Society Statement: Update on Limb Muscle Dysfunction in Chronic Obstructive Pulmonary Disease

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