Mid-cervical spinal cord contusion causes robust deficits in respiratory parameters and pattern variability

TY - JOUR

T1 - Mid-cervical spinal cord contusion causes robust deficits in respiratory parameters and pattern variability

AU - Warren, Philippa M.

AU - Campanaro, Cara

AU - Jacono, Frank J.

AU - Alilain, Warren J.

PY - 2018/8/1

Y1 - 2018/8/1

N2 - Mid-cervical spinal cord contusion disrupts both the pathways and motoneurons vital to the activity of inspiratory muscles. The present study was designed to determine if a rat contusion model could result in a measurable deficit to both ventilatory and respiratory motor function under “normal” breathing conditions at acute to chronic stages post trauma. Through whole body plethysmography and electromyography we assessed respiratory output from three days to twelve weeks after a cervical level 3 (C3) contusion. Contused animals showed significant deficits in both tidal and minute volumes which were sustained from acute to chronic time points. We also examined the degree to which the contusion injury impacted ventilatory pattern variability through assessment of Mutual Information and Sample Entropy. Mid-cervical contusion significantly and robustly decreased the variability of ventilatory patterns. The enduring deficit to the respiratory motor system caused by contusion was further confirmed through electromyography recordings in multiple respiratory muscles. When isolated via a lesion, these contused pathways were insufficient to maintain respiratory activity at all time points post injury. Collectively these data illustrate that, counter to the prevailing literature, a profound and lasting ventilatory and respiratory motor deficit may be modelled and measured through multiple physiological assessments at all time points after cervical contusion injury.

AB - Mid-cervical spinal cord contusion disrupts both the pathways and motoneurons vital to the activity of inspiratory muscles. The present study was designed to determine if a rat contusion model could result in a measurable deficit to both ventilatory and respiratory motor function under “normal” breathing conditions at acute to chronic stages post trauma. Through whole body plethysmography and electromyography we assessed respiratory output from three days to twelve weeks after a cervical level 3 (C3) contusion. Contused animals showed significant deficits in both tidal and minute volumes which were sustained from acute to chronic time points. We also examined the degree to which the contusion injury impacted ventilatory pattern variability through assessment of Mutual Information and Sample Entropy. Mid-cervical contusion significantly and robustly decreased the variability of ventilatory patterns. The enduring deficit to the respiratory motor system caused by contusion was further confirmed through electromyography recordings in multiple respiratory muscles. When isolated via a lesion, these contused pathways were insufficient to maintain respiratory activity at all time points post injury. Collectively these data illustrate that, counter to the prevailing literature, a profound and lasting ventilatory and respiratory motor deficit may be modelled and measured through multiple physiological assessments at all time points after cervical contusion injury.

KW - Cervical contusion

KW - Minute volume

KW - Respiration

KW - Respiratory EMG

KW - Tidal volume

KW - Ventilatory pattern variability

UR - http://www.scopus.com/inward/record.url?scp=85047087182&partnerID=8YFLogxK

U2 - 10.1016/j.expneurol.2018.04.005

DO - 10.1016/j.expneurol.2018.04.005

M3 - Article

C2 - 29653187

AN - SCOPUS:85047087182

SN - 0014-4886

VL - 306

SP - 122

EP - 131

JO - Experimental Neurology

JF - Experimental Neurology

IS - 0

ER -