Comparison of changes in heart rate variability and sacral skin perfusion in response to postural changes in people with spinal cord injury

Archives of Physical Medicine and Rehabilitation

Jones

et al. 2013

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Objective To compare the efficacy of various durations of wheelchair tilt-in-space and recline on enhancing skin perfusion over the ischial tuberosity in people with spinal cord injury (SCI). Design Repeated measures, intervention and outcomes measure design. Setting University research laboratory. Participants Power wheelchair users with SCI (N=9). Interventions Three protocols of various durations (3 min, 1 min and zero) of wheelchair tilt-in-space and recline were randomly assigned to the participants. Each protocol consisted of a baseline 15 min sitting, a duration of zero to 3 min reclined and tilted, a second 15 min sitting, and a 5 min recovery. The position at the baseline and second sitting was no tilt/recline of the participant and at the reclined and tilted and recovery was at 35° tilt-in-space and 120° recline. Main Outcome Measures Skin perfusion response to tilt and recline was assessed by laser Doppler and was normalized to mean skin perfusion at the baseline sitting. Results The results showed that mean skin perfusion during recovery at the 3 min duration was significantly higher compared to the 1 min duration (P<.017), and mean skin perfusion was not significantly different between the 1 min and zero durations (N.S.). Skin perfusion during the second sitting was significantly higher at the 3 min duration compared to the 1 min and zero durations (P<.017). Conclusions Our findings suggest that performing the 3 min duration of wheelchair tilt-in-space and recline is more effective than the 1 min duration on enhancing skin perfusion of weight bearing soft tissues.

Section: Discussionsupporting

confidence: 58%

Effect of Durations of Wheelchair Tilt-in-Space and Recline on Skin Perfusion Over the Ischial Tuberosity in People With Spinal Cord Injury

Archives of Physical Medicine and Rehabilitation

Jones

et al. 2013

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“…Physiological factors regulating microvascular responses include local metabolic and myogenic controls and central sympathovagal function over the cardiovascular system. 31, 40–42 The impaired microvascular reactivity in people with SCI is largely due to the sympathetic dysfunction over the cardiovascular system. 31, 42 To overcome sitting-induced tissue ischemia, local metabolic and/or myogenic controls need to cause a vasodilatory response to increase blood flow.…”

Section: Discussionmentioning

confidence: 99%

Comparison of Muscle and Skin Perfusion Over the Ischial Tuberosities in Response to Wheelchair Tilt-in-Space and Recline Angles in People With Spinal Cord Injury

Crane

Archives of Physical Medicine and Rehabilitation

et al. 2013

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Objective To compare the efficacy of wheelchair tilt-in-space and recline on enhancing muscle and skin perfusion over the ischial tuberosities in people with spinal cord injury (SCI). Design Repeated measures and before-after trial design. Setting University research laboratory. Participants Power wheelchair users with SCI (N=20). Interventions Six combinations of wheelchair tilt-in-space and recline angles were presented to participants in a random order. The testing protocol consisted of a baseline 5 min sitting with no tilt/recline and 5 min positioned in tilted and reclined position at each of 6 conditions, including: (1) 15° tilt-in-space and 100° recline, (2) 25° tilt-in-space and 100° recline, (3) 35° tilt-in-space and 100° recline, (4) 15° tilt-in-space and 120° recline, (5) 25° tilt-in-space and 120° recline, and (6) 35° tilt-in-space and 120° recline. Main Outcome Measures Muscle and skin perfusion was assessed by near-infrared spectroscopy and laser Doppler flowmetry, respectively. Results Muscle perfusion was significantly increased at 25° and 35° tilt-in-space when combined with 120° recline and skin perfusion was significantly increased at 3 tilt-in-space angles (15°, 25°, 35°) when combined with 120° recline and at 35° tilt-in-space when combined with 100° recline (P<.05). Even in the positions of increased muscle perfusion and skin perfusion (25° and 35° of tilt-in-space combined with 120° of recline), the amount of muscle perfusion change was significantly lower than the amount of skin perfusion change (P<.05). Conclusions Our results indicate that a larger angle of tilt-in-space and recline is needed to improve muscle perfusion compared to skin perfusion. A position of 25° tilt-in-space combined with 120° recline is effective in enhancing muscle and skin perfusion of weight-bearing soft tissues at the ischial tuberosities.

“…In addition, spectral and nonlinear complexity analyses of blood flow oscillations (BFO) have been performed to investigate the influences of the metabolic, neurogenic, and myogenic activities on cutaneous microvascular regulation [6, 30–32]. To date, impaired mechanisms for skin blood flow regulation have been found in the normal aging process [6, 33], as well as a variety of pathological conditions such as hypertension [21, 34], diabetes [23, 35, 36], and spinal cord injury [27, 37, 38]. …”

Section: Introductionmentioning

confidence: 99%

Skin blood flow dynamics and its role in pressure ulcers

Burns

Journal of Tissue Viability

2013

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Pressure ulcers are a significant healthcare problem affecting the quality of life in wheelchair bounded or bed-ridden people and are a major cost to the healthcare system. Various assessment tools such as the Braden scale have been developed to quantify the risk level of pressure ulcers. These tools have provided an initial guideline on preventing pressure ulcers while additional assessments are needed to improve the outcomes of pressure ulcer prevention. Skin blood flow function that determines the ability of the skin in response to ischemic stress has been proposed to be a good indicator for identifying people at risk of pressure ulcers. Wavelet spectral and nonlinear complexity analyses have been performed to investigate the influences of the metabolic, neurogenic and myogenic activities on microvascular regulation in people with various pathological conditions. These findings have contributed to the understanding of the role of ischemia and viability on the development of pressure ulcers. The purpose of the present review is to provide an introduction of the basic concepts and approaches for the analysis of skin blood flow oscillations, and present an overview of the research results obtained so far. We hope this information may contribute to the development of better clinical guidelines for the prevention of pressure ulcers.