Paradoxical Respirations in SCI?

[jelly221,RN, MSN]

OK, so I understand that with a spinal cord injury above T1, you'll have loss of innervation of the intercostal muscles, and so they'll be flaccid and collapsed, impeding breathing. What I'm confused about is why breathing is harder sitting? My book says

"The sitting position allows the abdomen to protrude and thus accentuates these paradoxical respirations. Many patients initially breathe more effectively in the supine position, although abdominal binders can be used to improve respiratory function when the patient is upright."

It seems like an abdominal binder would impede respiration further? Is it that it forces one to sit up straighter, increasing room for the viscera and allowing the diaphragm to descend further?

Please help me understand this!! =)

[Richard_Head]

This is a good question. I am not certain but I think a non-obese patient with a T1 lesion in the supine position will have difficulty generating a diaphragmatic excursion (thus creating a tidal volume) because the abdominal viscera will pull down on the diaphragm (gravity pulling down the organs that are unsupported by any skeletal muscle tone will act like an anchor on the diaphragm). While the innervation of the diaphragm (C3-4-5) is intact and thus functional, the abdominal skeletal muscle inervation (T7 at the xyphiod process, T10 at the umbilicus) is absent leaving only the diaphragm to provide the work of breathing. I would think an abdominal binder would mitigate the effects of gravity on the abdominal viscera and subsequentally prevent the diaphragm from being anchored in largely immobile position. Placing the patient supine would make the problem with the abdominal viscera a non-issue, unless they were obese which would lead to a new set of problems.