1. Practice Guidelines for the Prevention, Detection, and Management of Respiratory Depression Associated with Neuraxial Opioid Administration
Troy Tada, DO
October 21, 2009

2. Overview
This article was chosen to review the updated from previous ASA practice guidelines in 2007 for prevention, detection and management of respiratory depression associated with neuraxial opioid administration.
The updated includes new survey data and recommendation pertaining to monitoring for respiratory depression
The purpose of these guidelines are to improve patient safety and enhance quality of anesthetic care

3. Overview
These guidelines focus on the treatment of all patients receiving epidural or spinal opioids in inpatient or ambulatory settings
They do not apply to chronic or cancer pain, patients with preexisting implantable drug delivery systems

4. Overview Surveys given to two groups:
Task Force-appointed expert consultants
ASA member

5. Overview
The 2009 guidelines includes more specific recommendations in 4 areas:
Identification of patients at increased risk of respiratory depression (specific recommendations for focused history and physical examination);
Preventive strategies for respiratory depression after neuraxial opioid depression (recommendations for noninvasive positive pressure ventilation, drug selection, and dose selection);
Detection of respiratory depression and management (recommendations for monitoring for adequacy of ventilation, oxygenation, and level of consciousness);
Management and treatment of respiratory depression when it occurs (recommendations for supplemental oxygen, reversal agents, and noninvasive positive pressure ventilation).

6. Guidelines: Prevention
Identify pts at increased risk
Focused H/P
Literature suggests certain pt or clinical characteristics
Obesity, OSA, neuromuscular disease
Prior opioid administration

7. Guidelines Prevention
Noninvasive PPV: no agreement of its effectiveness
However, pts who already utilizes these devises are encouraged to bring their own equipment to the hospital
Single-injection VS Parenteral opioids
Both groups disagree that single injections increase the occurrence of RD when compared to parenteral
Single injection neuraxial opioids may be safely used in place of parenteral opioids without altering the risk of RD or hypoxemia

8. Guidelines: Drug selection
Prevention
Fentanyl-sufentanil VS morphine-hydromorphone
Single injection
Both groups agree that RD increase with morphine/hydromorphone
May be safely used in place of parenteral opioids without altering risk of RD or hypoxia
Continuous
Literature reports no difference in epidural adm.
However, ASA members agree that RD increase with morphine/hydromorphone
consultants are equivocal regarding this issue
Appropiate doses of continuous epidural fentanyl/sufentanil may be used in place of morphine/hydromorphone without increasing risk of RD

9. Guidelines: Drug selection
Prevention
Extended release morphine
Both groups equivocal regarding it increasing RD compared with either parenteral opioid or conventional epidural morphine
May be used in place of intravenous or conventional epidural morphine
Extended monitoring may be required

10. Guidelines: Drug selection
Prevention
Continuous epidural VS parenteral opioids
Meta-analysis of literature indicates less RD with continuous epidural
Both groups disagree that continuous epidural increase the occurrence of RD
Continuous epidurals preferred to parenteral for reducing the risk of RD

11. Guidelines: Drug selection
Prevention
Based on duration of action, morphine and hydromorphone should not be given to outpatient surgical patients

12. Guidelines: Dose selection
Prevention
Low VS high dose
Literature indicates RD reduced with low doses of single injections
However, no difference in RD or sedation when used in continuous epidural
Both groups strongly agrees RD increased with higher doses for intrathecal or epidural, in addition to continuous epidural
Recom: lowest efficacious dose should be administered to minimize RD
Neuraxial combined with parenteral
Literature is insufficient
Both groups strongly agree that it increases occurrence of RD
Recom: Parenteral opioids should be cautiously administered, requires increased monitoring (intensity, duration, methods)

13. Literature on Detection of RD
Insufficient to examine the efficacy of pulse oximetry or ETCO2 monitoring to diagnose RD for pt receiving neuraxial opioids
Comparative studies show
Pulse oximetryeffective in detecting hypoxemia in pt receiving a variety of anesthetic techniques
ETCO2 monitoring is effecting in detecting hypercapnia for parenteral opioids
Insufficient regarding using pulse oximetry, EKG, or ventilation is associated with improved detection of RD or hypoxemia for patients with neuraxial opioid

14. Pulse Oximetry/ETCO2/Level of Consciousness
Both groups disagree that pulse oximetry monitoring is more likely to detect RD than are clinical signs.
Both groups agree that continuous pulse oximetry monitoring is more likely to detect RD than periodic pulse ox monitoring
Both agree that ETCO2 monitoring is more likely to detect hypercapnia and RD than clinical signs
Both agree that checking level of alertness will identify pts at increased risk of RD

15. Guidelines: Detection
Monitoring
All patients receiving neuraxial opioids should be monitored for adequacy of ventilation RR
Depth or respiration
Oxygenation
Level of consciousness
In cases with concerning signs, it is acceptable to awaken a sleeping patient to assess level of consciousness

16. Guidelines: Detection
Detection: Single-Injection neuraxial
lipophilic opioid
Continual monitoring should be performed for the first 20 minutes after adm., followed by monitoring at least once/hour until 2 hours has passed
hydrophilic opioid
Monitoring should be performed for a minimum of 24 hours
First 12 hours: once per hour
Next 12 hours: once per 2 hours

17. Guidelines: Detection
Detection: Continuous infusion or PCEA
lipophilic /hydrophilic opioid
Monitoring should be performed during the entire time the infusion is in use
First 12 hours: Once per hour
Next 12 hours: once per 2 hours
After 24 hours: should be performed at least once every 4 hours
After discontinuation, monitoring should be dictated by the patient’s overall clinical condition and concurrent medications
Lipophilic opioid only
necessitates continual monitoring for the first 20 minutes

18. Guidelines: Detection
Detection: Sustained- or extended-release epidural morphine
First 12 hours: once per hour
Next 12 hours: once per 2 hours
After 24 hours: at least every 4 hours for a minimum of 48 hours

19. Guidelines: Management & Treatment
Supplemental O2: literature
Literature is insufficient to assess whether it will reduce the frequency or severity of hypoxia or hypoxemia
Literature does support use when non-neuraxial anes. Utilized

20. Guidelines: Management & Treatment
Supplemental O2: guidelines
Both groups agree on all three of following:
Should be available for any use of neuraxial opioids
Administer when, respiratory depression develops, hypoxemia, altered mental status
Routine use may increase duration of apneic episodes and hinder detection of atelectasis, transient apnea, and hypoventilation

21. Guidelines: Management & Treatment
Reversal agents
Literature: insufficient comparative studies to assess the efficacy with the use of naloxone or naltrexone
IV access should be established and/or maintained
Agents should be available
Administer when clinical signs of RD develop and initiate resuscitation

22. Guidelines: Management & Treatment
Non-invasive positive pressure ventilation
Should be considered for improving ventilation status
Should consider to utilize if frequent or severe airway obstruction or hypoxemia occurs during postoperative monitoring