The Effects of Respiratory Training with Inspiratory Flow Resistive Loads in Premature Infants

Abstract

ABSTRACT. Respiratory training of premature infants was performed to determine whether improved respiratory muscle strength and/or endurance would result. Twentytwo premature infants were randomized into control and training groups for 2 wk, using inspiratory flow-resistive loads for training (75 cm H 2 0 . L-' . s in wk 1 and 90 cm H20. L-' . s in wk 2). Respiratory endurance was assessed by the time interval required for the development of a 5-torr rise in transcutaneous C02 tension during the hypoventilation induced by loaded breathing, using a moderately severe resistive load (250 cm H 2 0 . L-' . s at 1 L. mine').Respiratory strength was assessed by the maximum negative airway pressure generated during occluded breaths, a pressure-time integral, and an effort index. Results revealed that respiratory muscle endurance, which was not initially different between control and trained groups, increased significantly after 2 wk in the trained group by 137% (median value, p < 0.05), whereas it remained unchanged in the control group (-24%). The trained group of infants also showed a significant decrease in baseline breathing frequency between the initial and final measurements taken 2 wk apart when compared with controls ( p < 0.05) and a lesser increase in inspiratory time with loading in the final measurement as compared with the initial value ( p < 0.05). There was no significant difference between the control and trained groups in initial or subsequent measures of respiratory muscle strength. Inspiratory flow-resistive load training appears to improve the respiratory endurance of premature infants in whom respiratory muscle fatigue has been described to play a role in the development of respiratory failure. (Pediatr Res 31: 613-618,1992) Abbreviations VT tidal volume VE, minute ventilation EI, effort index ET, endurance time IRL, inspiratory flow-resistive load MNAP, maximum negative airway pressure PTI, pressure-time integral TcPco2, transcutaneous C02 tension Ti, inspiratory time

Physical Properties of Bedding That May Increase Risk of Sudden Infant Death Syndrome in Prone-Sleeping Infants

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Mechanical ventilation, diaphragm weakness and weaning: A rehabilitation perspective

“…Other investigators followed the rationale for specific, voluntary exercises with uncontrolled case reports. They found that patients tolerated IMT, and many patients who had previously failed to wean were liberated from MV (Aldrich and Karpel, 1985; Aldrich and Uhrlass, 1987; Tan et al, 1992). Some of these studies used inspiratory resistance devices placed on the end of the endotracheal or tracheal tubes to provide the training stimulus and training was typically conducted for 10 – 15 minutes, twice a day with uncontrolled airflows and breathing frequencies (Aldrich and Karpel, 1985; Aldrich et al, 1989).…”