Comparison of airway responses in sheep of different age in precision-cut lung slices (PCLS).

Background: Animal models should display important characteristics of the human disease. Sheep have been considered particularly useful to study allergic airway responses to common natural antigens causing human asthma. A rationale of this study was to establish a model of ovine precision-cut lung slices (PCLS) for the in vitro measurement of airway responses in newborn and adult animals.

Time and volume dependence of dead space in healthy and surfactant-depleted rat lungs during spontaneous breathing and mechanical ventilation.

Volumetric capnography is a standard method to determine pulmonary dead space. Hereby, measured carbon dioxide (CO2) in exhaled gas volume is analyzed using the single-breath diagram for CO2. Unfortunately, most existing CO2 sensors do not work with the low tidal volumes found in small animals.

A method to measure mechanical properties of pulmonary epithelial cell layers.

The lung has a huge inner alveolar surface composed of epithelial cell layers. The knowledge about mechanical properties of lung epithelia is helpful to understand the complex lung mechanics and biomechanical interactions. Methods have been developed to determine mechanical indices (e.

Mechanostimulation, electrostimulation and force measurement in an in vitro model of the isolated rat diaphragm.

In an in vitro model of the entire rat diaphragm, diaphragmatic contraction forces at defined preload levels were investigated. A total of 24 excised rat diaphragms were electrically stimulated inside a two-chamber strain-applicator. The resulting contraction forces were determined on eight adjusted preload levels via measuring the elicited pressure in the chamber below the diaphragm.

Pressure support improves oxygenation and lung protection compared to pressure-controlled ventilation and is further improved by random variation of pressure support.

Objectives: To explore whether 1) conventional pressure support ventilation improves lung function and attenuates the pulmonary inflammatory response compared to pressure-controlled ventilation and 2) random variation of pressure support levels (noisy pressure support ventilation) adds further beneficial effects to pressure support ventilation.

Design: Three-arm, randomized, experimental study.

Setting: University hospital research facility.

Variable tidal volumes improve lung protective ventilation strategies in experimental lung injury.

Rationale: Noisy ventilation with variable Vt may improve respiratory function in acute lung injury.

Objectives: To determine the impact of noisy ventilation on respiratory function and its biological effects on lung parenchyma compared with conventional protective mechanical ventilation strategies.

Methods: In a porcine surfactant depletion model of lung injury, we randomly combined noisy ventilation with the ARDS Network protocol or the open lung approach (n = 9 per group).

Detrimental role of CC chemokine receptor 4 in murine polymicrobial sepsis.

CC chemokine receptor 4 (CCR4) and its two ligands, CCL17 and CCL22, are critically involved in different immune processes. In models of lipopolysaccharide-induced shock, CCR4-deficient (CCR4(-/-)) mice showed improved survival rates associated with attenuated proinflammatory cytokine release. Using CCR4(-/-) mice with a C57BL/6 background, this study describes for the first time the role of CCR4 in a murine model of polymicrobial abdominal sepsis, the colon ascendens stent peritonitis (CASP).

Pumpless extracorporeal lung assist for protective mechanical ventilation in experimental lung injury.

Objective: To test the hypothesis that ventilation with 3 mL/kg tidal volume combined with extracorporeal CO2 removal by arteriovenous interventional lung assist reduces ventilator-associated organ injury in experimental acute lung injury when compared with ventilation with 6 mL/kg tidal volume without interventional lung assist.

Design: Prospective, randomized, controlled trial.

Setting: A university research laboratory.