A tetraplegic @entity1 with C4 cervical @entity1566 reported @entity1353 during episodes of spastic contraction of the abdominal muscles. To determine the mechanism, we performed electrophysiologic testing of the phrenic nerves. We measured abdominal pressure, esophageal pressure, and transdiaphragmatic pressure (Pdi) during a maximal inspiratory effort (Pdi max), a maximal sniff maneuver (sniff Pdi) during resting breathing, and during the episodes of @entity1353 . Electrophysiologic testing of the phrenic nerves showed @entity16 on the left. Sniff Pdi and Pdi max were 38cm @entity2507 and 42cm @entity2507 , respectively. Transient @entity508 of abdominal muscles were associated with an increase in abdominal pressure greater than 30cm @entity2507 , with a decrease in abdominal volume; this rise in abdominal pressure was transmitted to the esophageal pressure. Inspiration became effective only when esophageal pressure fell below the resting baseline value. Achieving this decrease required an increase in inspiratory effort, characterized by swings in esophageal pressure and Pdi of 30cm @entity2507 and 40cm @entity2507 (approximately 100% of Pdi max), respectively. During these periods, minute ventilation was markedly reduced. This is the first report that spastic abdominal muscle contractions can impose a significant load on the diaphragm, uncovering moderate @entity425 . This has important clinical implications; abolition of the spastic abdominal muscle contraction in this @entity1 completely resolved her intermittent respiratory symptoms.

Breathlessness associated with @entity508 in a XXXX with C4 tetraplegia: a case report.

@entity1 :: ('9606', 'Species') :: ['patient'] @entity1353 :: ('MESH:D004417', 'Disease') :: ['breathlessness'] @entity16 :: ('MESH:D009422', 'Disease') :: ['axonal neuropathy'] @entity508 :: ('MESH:D009128', 'Disease') :: ['spastic contractions'] @entity425 :: ('MESH:D018908', 'Disease') :: ['diaphragmatic weakness'] @entity2507 :: ('CHEBI:33813', 'Chemical') :: ['H(2)O'] @entity1566 :: ('MESH:D013119', 'Disease') :: ['cord injury']
@entity1 :: (9606,Species) :: ['patient']
