Surface Electrical Myography, Oxygen Consumption (VO2), Effort, and Weaning in the Mechanically Ventilated Patient in the Intensive Care Unit (ICU)

In patients mechanically ventilated for more than 72 hours weaning from the
ventilator and successful extubation can be problematic. The spontaneous
breathing trial (SBT) is a tool to predict successful extubation. However
re-intubation withing 48 hours occurs in 15-20% of the patients after a
successful SBT. The key parameter of the SBT is the rapid shallow breathing
index (RSBI). Since the rate of extubation failure is still high the search for
a better parameter than the RSBI is warranted.
Recently measurement of the surface electromyography of the respiratory
muscles has become available with the Surface Electromyography Respiratory
Assist (SERA), which has been developed by Demcon-Macawi. The device is
currently investigated in neonates in search of an apnea detection algorithm
(protocol ID NL83937.000.23). The device gives an estimate of the magnitude of
the electric activity of the diaphragm which has a good correlation with the
force the diaphragm generates. It is known that the diaphragm is the key
respiratory muscle and that dysfunction of the diaphragm has a strong
association with weaning failure. We think that this signal could be of great
value in detecting weaning and extubation failure therefore we want to
investigate if the sEMG signal derived from the SERA device has an association
with weaning failure, defined as an unsuccessful SBT, or extubation failure,
defined as the need for re-intubation for respiratory reasons within 48 hours
after a successful SBT and subsequent extubation.

Primary objective is to investigate if the sEMG signal derived from the SERA
device has an association with weaning failure, defined as an unsuccessful SBT,
or extubation failure, defined as the need for re-intubation for respiratory
reasons within 48 hours after a successful SBT and subsequent extubation.
Secondary objectives are to investigate if the sEMG signal has an association
with other measurements of effort (pressure time product (PTP), Work of
breathing (WOB), Transpulmonary pressure swings, oesophageal pressure swings,
and oxygen consumption

A single center prospective cohort feasibility/pilot study performed on
patients undergoing a spontaneous breathing trial. Measurements will commence
10 minutes before the planned SBT, will continue during the SBT until 10
minutes after the termination of the SBT. Measurement data will be derived from
the SERA, the mechanical ventilator (Hamilton C6), and the Masimo ISA OR+. The
SBT will done according to the ruling protocol.

The collection of data will not affect the standard of care. Therefore, the
patient*s risk is negligible and the burden is minimal.