A comparison of pressure- and volume-controlled ventilation at different inspiratory to expiratory ratios.

Background: Inverse ratio ventilation (IRV) is frequently used in severe acute respiratory failure. IRV may lead to intrinsic positive end-expiratory pressure (PEEP) and is thought to improve oxygenation and to have advantageous effects on lung mechanics. Published data to support the use of IRV are scarce.

Volume-controlled inverse ratio ventilation in oleic acid induced lung injury. Effects on gas exchange, hemodynamics, and computed tomographic lung density.

Study Objective: To compare volume-controlled inverse ratio ventilation (VCIRV) with volume-controlled ventilation with conventional inspiratory to expiratory (I:E) ratio (VCV PEEP) at equal levels of end-expiratory pressure.

Design: Animal study using an oleic acid lung injury model with random application of VCV PEEP and VCIRV.

Setting: Experimental investigation at the Department of Clinical Physiology at Uppsala University.

Clinical application of differential ventilation with selective positive end-expiratory pressure in adult respiratory distress syndrome.

Differential ventilation in the lateral position with positive end-expiratory pressure (PEEP) selectively applied to the dependent lung (DVSP) has been shown to reduce venous admixture and improve oxygenation without compromising cardiac output in short term studies of patients with acute respiratory failure. We have applied this ventilation technique as a long-term treatment in severe adult respiratory distress syndrome (ARDS) in an open clinical trial. Eleven patients with ARDS of varying aetiology were treated with DVSP for a total of 34 days.

A functional and morphologic analysis of pressure-controlled inverse ratio ventilation in oleic acid-induced lung injury.

Study Objective: To compare volume-controlled ventilation (VCV PEEP) with pressure-controlled inverse ratio ventilation (PCIRV) at equal levels of end-expiratory pressure.

Design: Animal study using an oleic acid lung injury model with random application of VCV PEEP and PCIRV.

Setting: Experimental laboratory investigation at the Department of Clinical Physiology at Uppsala University.