System for automated adjustment of a pressure set by a ventilation device

Inventors

Novotni, Dominik • Laubscher, Thomas

Abstract

A system for automated adjustment of a pressure set by a ventilation device, in particular a positive and-expiratory pressure and/or a maximum airway pressure, the system comprising a pressure detection arrangement for detecting a transpulmonary pressure at the end of an expiration phase and/or for detecting a transpulmonary pressure at the end of an inspiration phase, and a device for automated adjustment of the pressure set by the ventilation device on the basis of the transpulmonary pressure detected at the end of the expiration phase and/or the transpulmonary pressure detected at the end of the inspiration phase.

Core Innovation

The invention relates to an automated ventilation control system that detects a transpulmonary pressure at an end of an expiration phase and/or at an end of an inspiration phase. A ventilation device sets a positive end-expiratory pressure based on the transpulmonary pressure detected at the end of the expiration phase, and a further ventilation setting includes setting a maximum airway pressure based on the transpulmonary pressure detected at the end of the inspiration phase. The pressure detection arrangement determines the respective transpulmonary pressure based on a difference between the respective alveolar pressure and the respective esophageal pressure.

The system determines the positive end-expiratory pressure in a subsequent breathing cycle using deviation of a transpulmonary pressure at the end of an expiration phase detected in m preceding breathing cycles from a normalized transpulmonary pressure at the end of an expiration phase, with m≥1. In addition, the system compares a positive end-expiratory pressure determined for the subsequent breathing cycle with a positive end-expiratory pressure set for the current breathing cycle, and changes the positive end-expiratory pressure only if the difference between the two values exceeds a predetermined threshold value.

The same threshold-based approach is used for comparing and changing a maximum airway pressure between subsequent and current breathing cycles, where applicable. The invention also defines control of maximum airway pressure by determining a maximum airway pressure in the subsequent breathing cycle based on a difference between an airway pressure at the end of an inspiration phase determined in m preceding breathing cycles and a positive end-expiratory pressure applied in m preceding cycles, with m≥1. The document further describes control based on transpulmonary pressure at end inspiration, positive end-expiratory pressure, and transpulmonary pressure at end expiration, including a predetermined maximum transpulmonary pressure at end inspiration and a starting value for the maximum airway pressure.

Claims Coverage

Independent claims cover at least two distinct control objectives: setting positive end-expiratory pressure (PEEP) based on transpulmonary pressure at end expiration, and setting maximum airway pressure based on transpulmonary pressure at end inspiration, using cycle-to-cycle control with memory across m preceding breathing cycles. Across the independent claims, the inventive features explicitly include transpulmonary pressure determination from alveolar and esophageal pressure differences, subsequent-cycle determination using m≥1, and threshold-based conditional updating for both PEEP and maximum airway pressure.

Overall claim coverage centers on calculating transpulmonary pressure as a difference between alveolar and esophageal pressure and using that detected transpulmonary pressure at end expiration and/or end inspiration to control ventilation pressures across breathing cycles. The independent claims further require subsequent-cycle determination using m≥1 and include cycle comparison with conditional updating based on a predetermined threshold for PEEP and/or maximum airway pressure.

Stated Advantages

Documented Applications