Disease relevance of Inspiratory Capacity

• We correlated preoperative PFT (forced expired volume in 1 sec, FEV1; vital capacity, VC; inspiratory capacity, IC; maximal inspiratory pressure, MIP; total lung capacity, TLC; and residual volume, RV) and postoperative MV days in 125 patients who had scoliosis surgery (aged 13.7 +/- 3.0 (SD) years) from January 1990-July 2001 [1].

High impact information on Inspiratory Capacity

• We measured the change in inspiratory capacity (Delta IC) during exercise to reflect changes in DH [2].
• Salbutamol induced an improvement of 0.16 +/- 0.02 L (mean +/- SD) in FEV(1), 0.36 +/- 0.04 L in forced inspiratory volume in one second (FIV(1)), 0.30 +/- 0.04 L in inspiratory capacity (IC), and -0.34 +/- 0.07 L in intrathoracic gas volume; the mean VAS score was 36.4 +/- 3 [3].
• In response to IB (n = 58): FEV(1), FVC, and inspiratory capacity (IC) increased by 7 +/- 1%pred, 10 +/- 1%pred, and 14 +/- 2%pred, respectively (p < 0.001), with no change in the FEV(1)/FVC ratio [4].
• The inspiratory capacity (IC) maneuver is increasingly used to monitor exercise-induced dynamic hyperinflation in patients with COPD [5].
• Under fresh (i.e., nonfatigue) conditions, aminophylline significantly increased Pdi,T at lung volumes above 75% of the inspiratory capacity (IC) [6].

Biological context of Inspiratory Capacity

• Spirometric parameters, slow vital capacity (SVC), inspiratory capacity (IC), and NEP were measured seated, before and after nebulised saline, and at intervals after 5 mg nebulised salbutamol and 500 microg nebulised ipratropium bromide [7].
• Using a stepwise regression analysis, percentage predicted functional residual capacity (FRC), the activity of CS, oxygen desaturation during exercise, age, and inspiratory capacity (% pred) were found to be significant determinants of peak VO(2) [8].
• Physiological responses to hyperoxia were characterized by decreases in total lung capacity and inspiratory capacity at 80 and 110 h [9].
• We also compared the effect of an inspiratory capacity (IC) breath of 8% CO2 with that of two tidal volumes (TV) at the same concentration (Protocol 2) [10].
• We used three different VT's (15 and 20 ml/kg and inspiratory capacity) under control conditions and a VT of 15 ml/kg after methacholine-induced bronchoconstriction [11].

Anatomical context of Inspiratory Capacity

• By day II, forced expiratory volume in 1 s (FEV1), inspiratory capacity (IC), PEF or VAS values and variability, sputum eosinophils and eosinophilic cationic protein (ECP) had improved [12].

Associations of Inspiratory Capacity with chemical compounds

• Compared with placebo, albuterol produced an increase in inspiratory capacity (1.87 +/- 0. 71 to 2.26 +/- 0.74 L, p = 0.002), which accounted for the increases in maximal and twitch transdiaphragmatic pressures [13].
• For secondary end points, patients receiving salmeterol had significant improvement in lung hyperinflation measured by inspiratory capacity which was evident at 4 weeks and maintained over 12 months (p = 0.035), and a significant improvement in health status measured by the St George's Respiratory Questionnaire at 12 months (p = 0.002) [14].
• Lung function testing showed reduction of the inspiratory capacity and the single-breath carbon monoxide transfer factor (TLCO) [15].
• In series II, each of the other 7 subjects performed 12 single breath N2 tests in which the subject inspired both 1 L and an inspiratory capacity (IC) of O2 from FRC with without 10 sec breath-holding [16].
• We used single inspiratory capacity breaths of 5, 6 or 8% CO2 in air to obtain ventilatory responses in normal subjects, with ensemble averaging of repeated runs to define stimulus and response (Protocol 1) [10].

Gene context of Inspiratory Capacity

• PATIENTS: Twenty-seven subjects with severe COPD (mean [+/- SD] age, 65 +/- 5 years of age; mean FEV1, 43 +/- 8% predicted; and mean inspiratory capacity [IC]; 74 +/- 14% predicted) [17].
• Dyspnoea was assessed using the Borg scale, FL by the negative expiratory pressure (NEP) method and hyperinflation in terms of decrease in inspiratory capacity (IC) [18].
• Adjusted mean pre-exercise inspiratory capacity (IC) on day 42 was 2.41 +/- 0.03 L (tiotropium) vs 2.19 +/- 0.03 L (placebo) at 2.25 h after dosing (p < 0.001), and 2.31 +/- 0.03 L (tiotropium) vs 2.16 +/- 0.03 L (placebo) at 8 h after dosing (p < 0.001) [19].
• Twenty-two patients with CF were studied (FEV1 17 to 112% of predicted) during progressive bicycle exercise, and changes in EELV were determined by repeat measures of inspiratory capacity [20].
• After the therapy, inspiratory capacity (IC) and vital capacity (VC) in both the 4 weeks-and 6 weeks-treated groups, and the forced expiratory volume in 1 second (FEV 1.0) in the 6 weeks-treated group were significantly increased, and CO2 retention had also improved [21].

Analytical, diagnostic and therapeutic context of Inspiratory Capacity

• Breathlessness (Borg scale), spirometry, and inspiratory capacity (IC) were measured after each dose during methacholine bronchoprovocation to a maximal change (delta) in FEV1 of 50% [22].

References