Respiratory Muscle Unloading during Mechanical Ventilation

  • J. Beck
  • J. Spahija
  • C. Sinderby
Conference paper


Mechanical ventilation is aimed at unloading the respiratory muscles and maintaining adequate ventilation. Webster’s dictionary states that ‘unloading’ is “to remove or discharge a load”; however, the aim in mechanical ventilation may just be to reduce the load. Unloading can be complete, as with controlled ventilation where the ventilator assumes all work and the respiratory muscles are inactive, or partial, where the ventilator assumes a portion of the workload and the respiratory muscles are active and contribute to the work performed. The ‘load’ to the respiratory muscles can be quantified as the force (pressure) that is required to displace the respiratory system in order to generate flow and volume. In patients with respiratory failure, this load is usually increased due to abnormal respiratory mechanics and intrinsic positive end-expiratory pressure (PEEPi) [1]. Also in such patients, the force generating capacity can be severely reduced [2], and therefore, what may appear to be a ‘normal’ load may actually represent an increased relative load.


Mechanical Ventilation Respiratory Muscle Respir Crit Pressure Support Ventilation Inspiratory Flow Rate 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • J. Beck
  • J. Spahija
  • C. Sinderby

There are no affiliations available

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