BACKGROUND: The effects of different modes of mechanical ventilation in the same ventilatory support level on ventilator-induced diaphragm dysfunction onset were assessed in healthy @entity95 . METHODS: Twenty @entity95 were randomly assigned to 4 groups (n = 5 in each group). Group 1: no mechanical ventilation; group 2: controlled mechanical ventilation ( @entity2834 ) for 24 hours; group 3: assist/control ventilation ( @entity6407 ) mode for 24 hours; group 4: high-level pressure support ventilation (PSV) mode for 24 hours. Heart rate, mean arterial blood pressure, PH, partial pressure of arterial @entity26 /fraction of inspired @entity26 and partial pressure of arterial @entity544 were monitored and diaphragm electrical activity was analyzed in the 4 groups. @entity522 was evaluated by protein analysis and diaphragm ultra structure was assessed by electron microscopy. RESULTS: The centroid frequency and the ratio of high frequency to low frequency were significantly reduced in the @entity2834 , A/C and PSV groups (P < 0.001). The percent change in centroid frequency was significantly lower in the PSV group than in the @entity2834 and A/C groups (P = 0.001 and P = 0.028, respectively). Electromyography of diaphragm integral amplitude decreased by 90%    1.48%, 67.8%    3.13% and 70.2%    4.72% in the @entity2834 , A/C and PSV groups, respectively (P < 0.001). @entity522 protein activation was attenuated in the PSV group compared with the @entity2834 and A/C groups (P = 0.035 and P = 0.033, respectively). Irregular swelling of mitochondria along with @entity174 and fuzzy cristae was observed in the @entity2834 group, whereas mitochondrial cristae were dense and rich in the PSV group. The mitochondrial injury scores (Flameng scores) in the PSV group were the lowest among the 3 ventilatory groups (0.93    0.09 in PSV versus 2.69    0.05 in the @entity2834 [P < 0.01] and PSV versus A/C groups [2.02    0.08, P < 0.01]). CONCLUSIONS: The diaphragm myoelectric activity was reduced in the PSV group, although excessive oxidative stress and ultra-structural changes of diaphragm were found. However, partial diaphragm electrical activity was retained and @entity130 was minimized using the PSV mode.

High-Level Pressure Support Ventilation Attenuates Ventilator-Induced Diaphragm Dysfunction in XXXX .

@entity522 :: ('836', 'Gene') :: ['Caspase-3'] @entity174 :: ('MESH:D050723', 'Disease') :: ['fractured'] @entity26 :: ('MESH:D010100', 'Chemical') :: ['oxygen'] @entity95 :: ('9986', 'Species') :: ['rabbits', 'New Zealand rabbits'] @entity2834 :: ('12305', 'Species') :: ['CMV'] @entity544 :: ('MESH:D002245', 'Chemical') :: ['carbon dioxide'] @entity6407 :: ('c|SUB|A||C', 'DNAMutation') :: ['A/C'] @entity130 :: ('MESH:D014947', 'Disease') :: ['diaphragm injury']
@entity95 :: (9986,Species) :: ['Rabbits']
