the monitoring of patients in the immediate
post-anaesthesia recovery period, 13 and this
includes monitoring:
• Pulse oximeter
• NIBP
• ECG
• Capnography if an airway device is in situ or
deeply sedated
• Temperature monitoring.
Additional monitoring
Cardiac output monitoring
The most accurate cardiac output monitor is the
pulmonary artery catheter, but the AAGBI no
longer recommends the routine use of this device
anywhere but specialist cardiac surgical centres.
A plethora of less invasive devices is now
available, but the accuracy of most devices
is debatable and no single device can be
recommended over another. However, cardiac
output monitors may have a role to play in
assessing fluid responsiveness, with some
evidence supporting their application for this
purpose. The use of echocardiography is also
recognised as an alternative for estimating cardiac
function and fluid status. Whichever device or
technique is used, training of anaesthetists using
them is imperative.
Depth of anaesthesia monitoring
Although there are limited data demonstrating
a reduction of accidental awareness during
general anaesthesia (AAGA), depth of anaesthesia
monitors may supplement clinical information.
The incidence of AAGA is highest when
By implementing the
recommendations made in the
guideline, anaesthetists and
departments are best positioned
to deliver safe anaesthesia
irrespective of location
neuromuscular blocking drugs are used with
total intravenous anaesthesia (TIVA), 8 therefore
the AAGBI recommend using these monitoring
devices in this clinical setting in particular.
When used, depth of anaesthesia monitoring
should commence at induction of anaesthesia
until the end of surgery and anaesthesia.
When maintaining anaesthesia with inhalation
anaesthetic agents, end-tidal anaesthetic vapour
monitoring is recommended with low agent
alarms set. The isolated forearm technique may
also be used, 14 but care interpretation and
management must be taken.
Neuromuscular blockade monitoring
The use of neuromuscular blocking drugs
mandates monitoring from induction through
to full recovery of blockade and consciousness.
Older, qualitative peripheral nerve stimulators are
less reliable and the AAGBI encourages replacing
these older devices with more objective
quantitative monitoring devices. Ideally,
quantitative monitoring using train-of-four
assessment, with a ratio of >0.9 representing
a return of motor function, should be used.
Stimulation of the ulnar nerve in particular
is ideal, however the facial or posterior tibial
nerves are alternatives. The importance of
neuromuscular blockade monitoring can be
appreciated by the finding of residual
neuromuscular blockade in up to 40% two
hours after administration, and the high risk
of both AAGA8 and postoperative pulmonary
complications associated with their use.
Regional anaesthesia and sedation
for operative procedures
As a minimum, the AAGBI recommends that
patients having regional anaesthesia procedures
require pulse oximeter, NIBP, ECG and, if sedated,
end-tidal carbon dioxide monitoring. The AAGBI
recommends that patients be monitored with
capnography whenever an anaesthetist
administers sedation, in any situation or location
that this may occur.
Monitoring during intra-hospital transfer
As previously noted, any anaesthetised or
sedated patient should have the same standard
of monitoring throughout transfer, be it
within hospital or without. 15 Before transfer,
physiological status should be optimised,
a sufficient oxygen supply to last the entire
duration of transfer should be checked, and
a pre-transfer checklist 8 should be used. Monitors
must include pulse oximetry, NIBP and ECG for
all patients, as well as end-tidal carbon dioxide,
airway pressure, tidal volumes and respiratory
rate in anaesthetised and ventilated patients.
Although portable depth of anaesthesia monitors
are not broadly available yet, the AAGBI suggests
that if available they should also be applied as
a standard of monitoring for patient transfers
when TIVA is being used.
Anaesthesia outside the operating theatre
Irrespective of location, the AAGBI recommends
the same minimum standards of monitoring
depending on whether general anaesthesia,
regional anaesthesia or sedation.
Conclusions
The 2015 standards of monitoring during
anaesthesia and recovery is a landmark guideline
that builds upon previous recommendations. The
use of capnography in all areas of anaesthetic care,
from sedation, to intra-hospital transfer, and
during recovery/waking up from anaesthesia or
sedation, is a progressive development in response
to a number of studies demonstrating the utility of
this monitor. The data from NAP58 has stimulated
encouragement for the use of both depth of
anaesthesia monitors and a more continuous
use of neuromuscular blockade monitors.
The recommendations also outline a minimum
standard of monitoring in a wide range of clinical
scenarios (Table 1), and describes the value of
cardiac output monitors in the assessment of
fluid responsiveness. By implementing the
recommendations made in this safety guideline,
anaesthetists and departments are best positioned
to deliver safe anaesthesia irrespective of location.
218
HHE 2018 | hospitalhealthcare.com
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Can J Anaesth 1988;35:265–9.
4 Webb RK et al. The Australian
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