Table. 3—

Recovery from acute exacerbations of chronic obstructive disease as indicated by changes in measurements from study entry (day 0) during follow-up visits

VariableDay 7Day 14Day 30Day 60Final visit
Subjects n817151520
Days post study entry7±115±130±163±360±5 (14–92)
Symptoms
 CRQ dyspnoea0.1±0.41.5±0.3**1.4±0.4**1.8±0.5**1.6±0.4**
 Modified MRC−0.8±0.3*−0.8±0.3**−0.9±0.4**-1.0±0.4**−0.8±0.3*
 TDI3.0±0.7**2.7±0.7**2.4±1.0*3.3±0.9*2.8±0.8**
 Dyspnoea at rest Borg−0.2±0.6−0.7±0.3-1.4±0.5*-1.1±0.5-1.6±0.4**
Pulmonary function
 FEV1 L0.00±0.090.12±0.06*0.13±0.06*0.24±0.06**0.19±0.05**
 FEV1/FVC %-2.5±2.4−0.2±2.11.2±1.82.0±1.91.4±1.8
 FEF25–75% L·s−1−0.07±0.040.01±0.040.04±0.030.04±0.040.03±0.03
 PEFR L·s−10.09±0.140.70±0.22**0.65±0.25**0.64±0.18**0.60±0.14**
 FVC L0.15±0.120.30±0.11**0.23±0.09**0.40±0.11**0.35±0.10**
 IC L0.06±0.070.26±0.06**0.27±0.07**0.30±0.06**0.30±0.05**
 SVC L0.27±0.10*0.34±0.11**0.32±0.07**0.47±0.12**0.38±0.10**
 TLC L0.07±0.15−0.00±0.090.12±0.070.13±0.070.09±0.06
 FRC L0.00±0.12−0.28±0.09**−0.16±0.10*−0.17±0.07*−0.20±0.06**
 RV L−0.21±0.11−0.41±0.11**−0.20±0.11*−0.34±0.12*−0.31±0.10*
sRaw % pred-15±50-133±57*-67±57-128±51*-102±43*
DL,CO/VA % pred6±1**2±3-2±31±32±3
Steady-state rest (room air)
Sa,O2 %0.4±0.21.6±0.81.5±0.52.8±0.9*2.1±0.9**
VO2 L·min−1−0.00±0.020.02±0.020.02±0.020.02±0.020.01±0.02
VCO2 L·min−10.00±0.010.01±0.020.02±0.020.02±0.020.01±0.02
VE L·min−1-1.8±1.1−0.7±0.6−0.1±0.5−0.3±0.7−0.3±0.6
VT L0.05±0.040.01±0.040.02±0.050.04±0.060.03±0.05
f breaths·min−1-4.0±0.7**-1.3±1.0−0.8±1.3-1.6±1.1-1.1±1.0
tI/tTOT−0.01±0.02−0.02±0.02−0.00±0.01−0.00±0.02−0.02±0.02
  • Data are presented as mean±sem. CRQ: Chronic Respiratory Disease Questionnaire; MRC: Medical Research Council dyspnoea score; TDI: transition dyspnoea index; FEV1: forced expiratory volume in one second; FVC: forced vital capacity; FEF25–75%: forced mid-expiratory flow; PEFR: peak expiratory flow rate; IC: inspiratory capacity; SVC: slow vital capacity; TLC: total lung capacity; FRC: functional residual capacity; RV: residual volume; sRaw: specific airway resistance; DL,CO: carbon monoxide diffusing capacity of the lung; VA: alveolar volume; Sa,O2: arterial oxygen saturation; VO2: oxygen consumption; VCO2: carbon dioxide arterial tension; VE: minute ventilation; VT: tidal volume; f: breathing frequency; tI: inspiratory time; tTOT: total breathing cycle. *: p<0.05 significant improvement from day 0 by paired t-test once a significant f ratio was obtained by ANOVA for repeated measures across all visit days; **p<0.01.