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. 2001 Mar 15;531(Pt 3):677–691. doi: 10.1111/j.1469-7793.2001.0677h.x

Table 3.

Mean relationships between Pepi and GG, and flow and GG in individual subjects

Pepivs. GG Flow vs. GG
r regression slope (% max EMG (% max EMG cmH2O−1)) r regression slope (% max EMG (ls−))
Experiment A
 1. Eucapnia, spontaneous breathing −0.76 ± 0.06 −0.71 ± 0.27 0.74± 0.06 2.70 ± 0.98
 2. Eucapnia,medium neg. press. vent. short Ttot −0.87 ± 0.03 −0.56 ± 0.26 0.86± 0.03 4.40 ± 1.79
 3. Hypocapnia, medium neg. press. vent. short Ttot −0.89 ± 0.03 −0.84 ± 0.45 0.88± 0.02 4.55 ± 1.97
 4. Eucapnia, high neg. press. vent. short Ttot −0.87 ± 0.03 −0.55 ± 0.18 0.83± 0.07 4.84 ± 1.61
 5. Hypocapnia, high neg. press. vent. short Ttot −0.89 ± 0.02 −0.51 ± 0.15 0.89± 0.02 4.24 ± 1.17
 6. Hypocapnia, medium neg. press. vent. long Ttot −0.88 ± 0.02 −0.60 ± 0.24 0.88± 0.02 3.75 ± 1.50
 7. Hypocapnia, high neg. press. vent. long Ttot −0.86 ± 0.04 −0.39 ± 0.15 0.88± 0.03 3.13 ± 1.01
Experiment B
 8. Eucapnia, spontaneous breathing −0.86 ± 0.03 −1.32 ± 0.36 0.85± 0.04 5.16 ± 1.69
 9. Hypercapnia, spontaneous breathing −0.83 ± 0.03 −0.95 ± 0.22 0.83± 0.04 4.89 ± 1.18
10. Eucapnia, medium neg. press. vent. −0.77 ± 0.09 −0.65 ± 0.19* 0.78± 0.08 6.06 ± 2.31
11. Hypercapnia, medium neg. press. vent. −0.79 ± 0.09 −0.73 ± 0.15 0.84± 0.06 7.25 ± 1.93

There was a significant relationshipbetween negativePepi and GG EMG,andbetweenflow and GG EMG in almost all subjects in all conditions (92of 95 individual correlations were significant). The means (±s.e.m.) of these relationships areshown. Thus,negative Pepi and flow were equally good predictors of GG EMG during spontaneous breathing at variouslevels of Pet,co2, andduring passive mechanical ventilation at various tidal volumes, breathing frequencies and levels of Pet,co2. There were no significant differences in r between conditions ineach experiment. Within each experiment there were no significant differences among conditions in theslope of therelationships between flow andGG EMG,or between Pepi and GG EMG, with the single exceptionof conditions 8vs. 10 in experiment B

*

(P <0.05).