Table 2 Comparison of respiratory parameters at 08.00 h (after NIPPV) and 20.00 h (before NIPPV) in group 4 patients with evening breathlessness
08.00 h20.00 h
VC (ml)*704 (195) (573 to 835)642 (153) (539 to 745)
RR (breaths/min)**19.6 (2.5) (17.9 to 21.2)25.8 (8.1) (20.4 to 31.2)
Ti/Ttot0.44 (0.04) (0.41 to 0.47)0.44 (0.05) (0.4 to 0.47)
MIP (cm H2O)14 (5.6) (10.2 to 17.7)13.6 (6.1) (9.5 to 17.7)
TT0.1**0.046 (0.021) (0.031 to 0.06)0.081 (0.035) (0.58 to 0.1)
Tlim (s)*202 (197) (70 to 334)149 (183) (26 to 172)
Tcco2 (mm Hg)45.5 (7.8) (40.3 to 50.8)46.3 (7.9) (40.9 to 51.6)

  • Data are presented as mean (SD) with 95% confidence intervals.

  • VC, vital capacity; RR, respiratory rate; Ti, inspiratory time; Ttot, total breath time; Ti/Ttot, duty cycle; MIP, maximum inspiratory pressure; TT0.1, tension-time index; Tlim, muscle endurance time; Tcco2, transcutaneous carbon dioxide tension.

  • *p<0.05; **p<0.01 (paired t test 08.00 vs 20.00 h).