PIC 1:The pressure-time scalar exhibits pressure drops varying in amplitude beneath the baseline. Smaller pressure drops (0.5 cm H2O) and larger pressure drops (2 cm H2O) arise from cardiac pulsations and patient's inspiratory efforts, respectively. PIC 2: False trigger (also known as auto trigger) Opting for a pressure trigger sensitivity threshold of 0.5 cm H2O can lead to both cardiac oscillations and inspiratory efforts meeting this threshold, leading to a situation wher

Work shifting: During the initial phase of inspiration, the pressure is lower than the set Positive End-Expiratory Pressure (PEEP) because of the large inspiratory efforts (strong Pmus). Late cycling (delayed cycling): As the inspiratory muscles relax and expiratory muscles contract, the pressure waveform rises above the baseline. The patient completes a breath (inspiration and expiration) and begins another breath within the set inspiratory time. This can be identified by

Pic 1: The first image shows an upward deformation of the early portion of expiratory flow-time scalar (decreased expiratory flow) becuase of continuation of neural inspiration afte the end of mechanical inflation.  Pic 2: There are two breaths separated by a small gap (incomplete expiration) which is known as double trigger. Early cycle can lead to double trigger if neural inspiration continues beyond mechanical inspiratory phase and reaches the trigger sensitivity threshold

A failed trigger occurs when a patient's inspiratory effort fails to generate pressure or flow changes required to reach the trigger sensitivity threshold of a ventilator, and as a result, the ventilator does not initiate the delivery of a breath.  This can happen for various reasons, including: a) Respiratory muscle weakness: The first example illustrates a failed trigger due to muscle weakness. On the left side of the image, you can observe a pressure-time scalar with a no

Early cycling: Ventilator ends inspiratory phase before the end of neural inspiration.  Early cycling leads to an upward deformation of the expiratory flow time scalar. The application of inspiratory pause results in a flat line in the pressure-time scalar when the respiratory muscles remain inactive during that phase. In this scenario, the plateau is not seen as the inspiratory muscles remain engaged, resulting in reduced pressures. Suspect early cycling if there is an upwar

Work shifting: During early inspiratory phase, the pressure-time scalar is deviated towards the baseline indicating strong inspiratory effort  Late Cycling: with relaxation of inspiratory muscles and contraction of expiratory muscles the pressure rises above the baseline. Patient completes one breath and starts another breath during the same inspiratory phase (identified by the pressure drop during late inspiratory phase). This pressure drop is sensed by the ventilator and