Breathing with additional negative pressure during inhalation significantly decreased median respiratory rate from 16.4 to 6.9 min-1 and increased tidal volume in healthy volunteers.
Does breathing with additional negative pressure during inhalation affect respiratory rate and gas exchange in healthy volunteers in the antiorthostatic position?
Breathing with additional negative pressure during inhalation in the antiorthostatic position decreases respiratory rate and minute ventilation while increasing tidal volume and respiratory exchange ratio, suggesting increased gas exchange efficiency.
Absolute Event Rate: 6.9% vs 16.4%
The paper examines the effect of breathing with additional negative pressure during inhalation (NPBin, –20 cm H 2 O) on breathing and gas exchange in a healthy person in the antiorthostatic position (‒8° relative to the horizontal). It was found that with NPBin, the respiratory rate significantly decreased. Median (M), 1st (Q1) and 3rd (Q3) quartiles were: before NPBin M = 16.4 min –1 , Q1 = 13.4 min –1 and Q3 = 18.5 min –1 ; during NPBin M = 6.9 min –1 , Q1 = 5.7 min –1 and Q3 = 10.2 min –1 . In individual volunteers, the respiratory rate decreased to 4−5 cycles per minute. With NPBin, tidal volume increased: before NPBin M = 0.50 L, Q1 = 0.43 L, Q3 = 0.56 L; during NPBin M = 0.66 L, Q1 = 0.56 L, Q3 = 1.07 L. Changes in respiratory rate and tidal volume were accompanied by a decrease in the minute volume: before NPBin M = 9.6 L/min, Q1 = 7.8 L/min, Q3 = 10.0 L/min; during NPBin M = 6.7 L/min, Q1 = 5.7 L/min, Q3 = 8.2 L/min. Also, with NPBin, the respiratory exchange ratio increased: before NPBin M = 0.777, Q1 = 0.722, Q3 = 0.817; during NPBin M = 0.875, Q1 = 0.818, Q3 = 0.916. Despite the decrease in minute ventilation, there are signs of СО 2 washout from the body tissues during NPBin, which indirectly indicates an increase in the efficiency of gas exchange in the lungs during NPBin.
Yu. S. Semenov (Mon,) conducted a other in Healthy. Breathing with additional negative pressure during inhalation (NPBin) vs. Before NPBin (baseline) was evaluated on Respiratory rate (min-1). Breathing with additional negative pressure during inhalation significantly decreased median respiratory rate from 16.4 to 6.9 min-1 and increased tidal volume in healthy volunteers.