Is One Anesthetic Technique Associated with Faster Recovery?

1. Is One Anesthetic Technique Associated with Faster Recovery? Or “Time Equals Money” Trey Bates, MD

2. The Case • 60 year-old Woman • HTN (controlled on beta blocker) • Tobacco (17 pack-year history) • Right Inguinal Hernia Repair • Allergic to Amide and Ester Local Anesthetics

3. The Catch • You work at a busy surgical center • Prefer to bypass PACU and take patients directly to outpatient surgery.   • Is that possible in this case?   • How would you accomplish this?

4. The Article • Emphasis on rapid postoperative recovery and early discharge • PACU stay is questioned • There is evidence that the choice of general anesthetic technique is associated with faster recovery • The most important aspect of an anesthetic technique is its ability to consistently achieve rapid recovery after termination of surgery

5. Premedication Your Thoughts?

6. Premedication • Benzodiazepines often used to provide anxiolysis and reduce incidence of intraoperative awareness • Recent evidence suggests that recovery, particularly in the elderly, may be prolonged

7. Premedication • However, significant reduction in stress hormone levels after diazepam premedication found by Duggan (2002) using Diazepam 0.1 mg/kg 60 or 90 minutes preoperatively) • Benzodiazepine premedication only in high-risk (e.g., cardiac patients) undergoing ambulatory surgery

8. Induction Your Thoughts?

9. Induction • Propofol versus Sevoflurane • Thwaites, 1997 • Induction with Propofol then 2% Sevo Maintenance • Induction with 8% Sevo then 2% Sevo Maintenance

10. Induction • Time to emergence (eye opening to command) was shorter in patients with Sevoflurane induction (5.2 minutes versus 7 minutes) • However, incidence of PONV was higher after Sevoflurane induction • Significantly more patients rated induction with Sevoflurane as unpleasant • Since Propofol induction is associated with higher perioperative patient satisfaction, Sevoflurane ahould be reserved for selected patients

11. Maintenance Your Thoughts?

12. Maintenance • Ease of titratability and a rapid emergence from anesthesia favor inhaled anesthetic techniques • In addition, inhaled anesthetics potentiate neuromuscular blockade, thereby reducing the requirements of muscle relaxants • Desflurane and Sevoflurane allow for more rapid emergence than Isoflurane

13. Maintenance • Desflurane versus Sevoflurane versus Propofol • Song, 1998 • Inhaled anesthetic resulted in shorter times to awakening, tracheal extubation, and orientation compared to Propofol TIVA • 90% of Desflurane patients were considered fast-track eligible (Sevo – 75%, Propofol – 26%)

14. Maintenance • However, there was no difference between the groups with respect to the times to oral intake and home-readiness. • Faster emergence does not translate into an earlier discharge from the PACU

15. Maintenance • Propofol TIVA is consistently associated with a lower incidence of PONV as compared with inhaled anesthetic technique • However, PONV incidence is equivalent when prophylactic antiemetics are used with inhalation anesthesia and Nitrous Oxide • Propofol TIVA is preferable in high risk PONV patients

16. Nitrous Oxide Your Thoughts?

17. Nitrous Oxide • Amnestic and Analgesic Properties • Lower the requirement of costly anesthetic drugs • Some studies report a higher incidence of PONV with Nitrous Oxide • A meta-analysis of randomized controlled trials found that the emetic effect of Nitrous Oxide was not significant

18. Nitrous Oxide • Arellano, 2000 • 740 women • Outpatient gynecologic surgery • Incidence of PONV and time to home-readiness • Propofol-Nitrous Oxide versus Propofol alone • Nitrous Oxide reduced propofol requirements 20% to 25% without increasing adverse events

19. Nitrous Oxide • Most studies assessing the feasibility of fast-tracking have used nitrous oxide as part of their technique • Overall, there is no convincing evidence to avoid Nitrous Oxide

20. Supralaryngeal Airway Devices Your Thoughts?

21. Supralaryngeal Airway Devices • Do not require NMB • Generally tolerated at lower anesthetic levels than a tracheal tube • Opiod requirements can be based on respiratory rate • Desflurane has irritant properties but can be safely used in patients breathing spontaneously through an LMA

22. Opiods Your Thoughts?

23. Opioids • Nausea, vomiting, and sedation contribute to delayed recover and discharge home • Use sparingly in ambulatory surgery • Remifentanil • Rapidly Metabolized = Very short duration of action • Independent of duration of infusion • Reliable and Rapid emergence • Because of its short duration of action, plan for longer-acting analgesics before discontinuation

24. Areas of Uncertainty • Does the use of a small dose (2 mg)of midazolam protect against awareness or delay recovery from anesthesia? • Does the use of nitrous oxide reduce intraoperative and/or postoperative opioid requirements? • Are longer-acting opioids (morphine and hydromorphone) suitable for anesthesia practice?

25. Author’s Recommendations • Intravenous induction is preferable • Maintenance with Sevo or Des • Des may be associated with faster emergence • Optimal Technique = intravenous propofol induction, inhalation anesthesia with Nitrous Oxide for maintenance, and an LMA