title: Effect of pressure support ventilation on breathing patterns and respiratory work.
abstract: We assessed the effect of pressure support ventilation (PSV) on breathing patterns and the work of breathing in 10 postoperative patients. Minute ventilation (VE) increased by 8% with 5 cm H2O PSV and 10% with 10 cm H2O PSV compared to 0 cm H2O PSV. The increase in VE was achieved by increased mean inspiratory flow (24% with 5 cm H2O PSV and 67% with 10 cm H2O PSV) and a decrease in duty cycle (13% with 5 cm H2O PSV and 39% with 10 cm H2O PSV). The decrease in duty cycle along with a decrease in respiratory frequency allowed a greater expiratory time including a rest period for the respiratory muscles, which might minimize the risk of muscle fatigue. Furthermore, the inspiratory work added by the ventilator was near zero with 5 cm H2O PSV and 10 cm H2O PSV. Oxygen consumption also decreased significantly with 5 cm H2O PSV. We conclude that PSV improves the breathing patterns and minimizes the work of breathing spontaneously via a ventilator.
authors.affiliation: Department of Anesthesiology and Resuscitology, Okayama University Medical School, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Tokioka
authors.forename: S
authors.initials: S
authors.lastname: Saito
authors.forename: F
authors.initials: F
authors.lastname: Kosaka
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001784:Blood Gas Analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D010101:Oxygen Consumption; D010313:Partial Pressure; D012119:Respiration / Q000502:physiology*; D012121:Respiration, Artificial; D014939:Work of Breathing / Q000502:physiology*
chemical_list: D010100:Oxygen