Ventilatory parameters in heart failure patients with 0, 250 and 500 mL of additional dead space.

Data are presented as means ± SD; VE = ventilation; RR = respiratory rate; VT = tidal volume; VD = dead space volume; VCO2 =  carbon dioxide production; PaCO2 =  arterial carbon dioxide pressure; PETCO2 = End-tidal carbon dioxide pressure; bpm =  breaths per minute;
$: p<0.05 vs. 250 mL; μ: p<0.001 vs. 500 mL; *: p<0.001 vs. 250 mL; &: p<0.01 vs.500 mL; #<0.01 vs. 250 mL.