volume delivered [6], it did facilitate faster
weaning when compared with PSV [7] However,
it could be argued that COPD patients are usually
difficult to wean and should be carefully managed
to prevent any iatrogenic harms such as air leaks
which might occur as a result due to their highly
compliant lung.And although the mode minimizes
clinician's intervention which might minimize errors and prevent
delay in weaning, their intervention might be needed when the
ventilator provides more/less support needed when it is used as an
initial mode of ventilation.Acute Respiratory Distress Syndrome (ARDS)
and Acute Lung Injury (ALI) hence, one research
indicated that ASV could provide more than
10ml/kg in such case [8] which does not follow
lung protective strategies currently recommended
for such lung abnormality [9].The patient is weaned from sedation, oriented with
adequate level of consciousness
Comparison with Other Weaning Modes
A literature search on comparative studies between ASV and
other weaning modes were conducted, for the aim of identifying the
advantages of ASV over any of them if any.And although this time the
ASV mode showed no superiority over SIMV followed by PS in the
length of tracheal intubation, ICU stay, and amounts of postoperative
sedation, the advantages of less clinician intervention needed might
considered as an advantage for the ASV mode.However,
the major concern within the weaning protocol was edited; by
depending on the normalization of the PaCO2 value instead of taking
extra 6 spontaneous breaths, which might be considered as a more
reliable indicator for the patients allocated to the SIMV group to be
eligible for the next phase of weaning.Interestingly, they stated that ASV
delivered significantly higher tidal volumes, which might be beneficial
for post open heart surgery patients who are prone to derecrutment,
but it might be against the current recommendation about protective
lung strategies using less volume.And although, their protocol for the PC group
stated that once there was detected spontaneous breaths it was their
indicator to switch the patients to PSV, the mandatory breaths on
PC was set at 12-15 BPM which might be satisfactory for stable post-
operative patients.In one study compared
between ASV and Synchronised Intermittent Mandatory Ventilation
(SIMV) followed by Pressure Support (PS) following a three phases
protocol ASV group were extubated faster than SIMV followed by PS
group [10].Furthermore, it would
be interesting to investigate the differences between ASV mode and
SIMV+PS mode, since most of the current ventilators provide SIMV
+ PS as a single mode.When the targeted ABG values is reached which includes
acceptable oxygenation PaO2>60 on FiO2