Endotracheal Pressure Changes Research Articles

Effect of residual leaning force on intrathoracic pressure during mechanical ventilation in children

Aim Determine the effect of residual leaning force on intrathoracic pressure (ITP) in healthy children receiving mechanical ventilation. We hypothesized that application of significant residual leaning force (2.5 kg or 20% of subject body weight) would be associated with a clinically important change in ITP. Methods IRB-approved pilot study of healthy, anesthetized, paralyzed mechanically ventilated children (6 months to 7 years). Peak endotracheal pressure (ETP), a surrogate of ITP, was continuously measured before and during serial incremental increases in sternal force from 10% to 25% of the subject's body weight. A delta ETP of ≥2.0 cmH 2O was considered clinically significant. Results 13 healthy, anesthetized, paralyzed mechanically ventilated children (age: 26 ± 24 m, range: 6.5–87 m; weight: 13 ± 5 kg, range: 7.4–24.8 kg) were enrolled. Peak ETP increased from baseline for all force applications (10% body weight: mean difference of 0.8 cmH 2O, p < 0.01; 15% body weight: mean difference of 1.1 cmH 2O, p < 0.01; 20% body weight: mean difference of 1.5 cmH 2O, p < 0.01; 25% body weight: mean difference of 1.89 cmH 2O, p < 0.01). Residual leaning force of ≥2.5 kg was associated with a 2.0 cmH 2O change in peak ETP (odds ratio 7.5; CI 95 1.5–37.7; p = 0.014) while sternal force ≥20% body weight was not (odds ratio 2.4; CI 95 0.6–9.2; p = 0.2). Conclusion In healthy anesthetized children, changes in ETP were detectable at residual leaning forces as low as 10% of subject body weight. Residual leaning force of 2.5 kg was associated with increases in ETP ≥2.0 cmH 2O.

Effects of capsaicin, potassium and histamine on the endotracheal pressure changes and neuropeptides release from gulnea-pig lung in vitro

Effects of capsaicin, potassium and histamine on the endotracheal pressure changes and neuropeptides release from gulnea-pig lung in vitro

An evaluation of the performance of minimal resistance non-rebreathing systems.

Minimal resistance to spontaneous respiration has been proposed as a safe method for reducing operative bleeding. The Magill, Bullough, and Gilston T-piece non-rebreathing systems have been tested for resistance in steady-state conditions of pressure gradient and gas flow. The slope of the lines on the graph of the pressure gradient within an endotracheal tube against the squared value of the simulated expiratory flow rate illustrated the low resistance characteristics of the Gilston T-piece compared with the Magill and Bullough systems. In a within-patient trial, the resistance characteristics of the Gilston T-piece and Magill systems were confirmed by measuring the patterns of airway flow and endotracheal pressure changes with rapidly responding transducers. In conclusion, the Gilston T-piece system offers the least resistance to respiration of those tested, and provides the greatest opportunity for assessment of reduced operative bleeding in a clinical trial.