Monitoring of Analgesia Depth During Surgery

Basic Principles of Analgesia Monitoring

The American Society of Anesthesiologists recommends continual monitoring of ventilatory function through observation of qualitative clinical signs during procedural sedation and analgesia 2
The American Society of Anesthesiologists recommends regular assessment of a patient's response to verbal commands (e.g., at 5-minute intervals) during moderate sedation to gauge consciousness level 2

Processed EEG monitoring, such as bispectral index (BIS), is strongly recommended for monitoring anesthesia depth, particularly in patients over 60 years of age 1, 3
For elderly patients (>60 years), targeting a lighter level of anesthesia with a BIS of approximately 50 can significantly reduce postoperative delirium 1, 4
Avoiding burst suppression of the EEG is critical as it increases the risk of postoperative delirium in older patients 1, 3

For patients over 60 years at risk of postoperative delirium and anesthesia-induced hypotension, depth of anesthesia monitoring is strongly recommended 3
Close monitoring of age-adjusted minimum alveolar concentration (MAC) is critical to avoid side effects such as hypotension in elderly patients 1
For patients undergoing emergency laparotomy, depth of anesthesia monitoring is particularly important due to the high incidence of frailty and old age which increases the risk of postoperative delirium 3

Processed EEG-guided anesthesia care may facilitate rapid emergence and recovery, according to recent reviews 3

The American Society of Anesthesiologists recommends that a patient's level of consciousness, ventilatory and oxygenation status, and hemodynamic variables should be recorded at a frequency dependent on medication administered, procedure length, and patient condition 2
The American Society of Anesthesiologists recommends that documentation should occur: before administration of sedative/analgesic agents, after administration, at regular intervals during the procedure, during initial recovery, and just before discharge 2
The American Society of Anesthesiologists recommends that device alarms should be set to alert the care team to critical changes in patient status 2