Essential monitoring strategies to detect clinically significant drug- induced respiratory depression in the postoperative period Anesthesia Patient Safety Foundation (APSF)
These Conclusions and Recommendations are intended to facilitate
detection of clinically significant drug-induced respiratory
depression in non-ambulatory adult patients receiving parenteral
opioids for management of acute postoperative pain while being
cared for in a healthcare facility.
Conclusions and Recommendations
Future technology developments may improve the ability to
more effectively utilize continuous electronic monitoring of
oxygenation and ventilation in the postoperative period.
However, maintaining the status quo while awaiting newer
technology is not acceptable.
Intermittent “spot checks” of oxygenation (pulse oximetry)
and ventilation (nursing assessment) are not adequate for
reliably recognizing clinically significant evolving drug-induced
respiratory depression in the postoperative period.
Continuous electronic monitoring of oxygenation and
ventilation should be available and considered for all patients
and would reduce the likelihood of unrecognized clinically
significant opioid-induced depression of ventilation in the
Continuous electronic monitoring should complement and not
replace traditional intermittent nursing assessment and
All patients should have oxygenation monitored by continuous
pulse oximetry (see Observation 1).
Capnography or other monitoring modalities that measure the
adequacy of ventilation and airflow is indicated when
supplemental oxygen is needed to maintain acceptable oxygen
Although careful preoperative screening for conditions that
may be associated with an increased risk of postoperative
respiratory insufficiency (obstructive sleep apnea, obesity,
chronic opioid therapy) is recommended and may be part of a
graduated continuous monitoring adoption plan, applying
electronic monitoring selectively based upon perceived increased
risk is likely to miss respiratory depression in patients without
risk factors (see Observation 2).
Monitoring continuous oxygenation and ventilation from a
central location (telemetry or comparable technologies) is
desirable. This information needs to be reliably transmitted to
the healthcare professional caring for the patient at the
Structured assessment of the level of sedation/consciousness
is a critical component of the nurse’s routine postoperative
patient assessment for detecting respiratory depression.
Nurse and physician education is critical to ensure an (1)
understanding of the physiology and pharmacology of drug-induced
respiratory depression, (2) the potential obscuring impact of
patient arousal on respiratory depression during clinical
assessment and (3) the interference of supplemental oxygen
administration on detection of progressive hypoventilation when
pulse oximetry is the only continuous electronic monitor.
Continuous electronic monitoring systems should integrate
multiple physiologic parameters to identify clinically
significant changes earlier and more reliably.
Threshold-based alarm limits on individual physiologic
parameters may result in the caregiver failing to recognize early
signs of progressive hypoventilation by either being too
sensitive (excess false alarms) or insufficiently sensitive.
Impediments to continuous electronic monitoring of
oxygenation and ventilation in the postoperative period are
multifaceted. Among attendees categorizing their responses to the
written questions as Caregivers orCorporate the
two greatest impediments were (1) initial investment cost in
instituting existing technology and (2) failure of caregivers to
recognize (inadequate education) the true risk of drug-induced
APSF is aware of hospital systems that have adopted
continuous capnography in combination with pulse oximetry, or in
lieu of pulse oximetry.
APSF acknowledges that, due to limited healthcare resources,
implementation of these conclusions and recommendations may be
part of a graduated continuous electronic monitoring adoption
plan. However, institution of these conclusions and
recommendations must not be delayed while awaiting newer
APSF advocates increased public and private investment in
research to develop monitors with high reliability and ease of
APSF strongly encourages research and continuous quality
improvement (CQI) to evaluate the impact and cost effectiveness
of these Conclusions and Recommendations.
APSF believes that multimodal analgesia techniques need to be
used more often to decrease the use of opioids alone for
postoperative pain management.