Jhi-Joung Wang, MD, et.al. Anesthesia and Analgesia 2000; 91:136-9.

Reviewed by: R. Prasad, MD

Conclusion:
Dexamethasone 10mg given 1 minute before induction worked better than when given after extubation, and better than placebo.
Does not answer ... optimal dose? duration of action?

Details:
Nice Study
-A randomized, double-blinded, placebo-controlled study.
-120 ASA I-II women for abdominal TAH under GA.
-Exclusion criteria: h/o motion sickness, GI disorders, or received antiemetics within 48hrs before surgery
-Randomly divided into 3 groups of 40 each. All received study drug A 1min before induction and drug B just after extubation (pts and MDs blinded). They
compared 10mg dexamethasone (Dex) and saline:
Group #)   A         B
           1) Dex     saline
           2) saline    Dex
           3) saline   saline
-Standard induction propofol, glycopyrrolate, fentanyl
-Vecuronium, isoflurane 1-2.5% inspired in oxygen
-Fentanyl supplemented prn
-Standard reversal, glycopyrrolate and neostigmine
-Observed in PACU 2hrs, then on floor 2-24 hrs
-PACU: MSO4 bolused for pain, then PCA
If Only...
-Better control of isoflurane concentration and fentanyl doses?
-Larger numbers always better. Although differences not statistically significant, Group 1 had slightly shorter surgery/anesthesia, slightly lower perioperative fentanyl,
and slightly lower VAS pain scores at 1 and 2 hours (all very small differences).

Results
-No signif demographic differences between groups (age, height, weight, last menstrual period, surgery type, anesthesia/surgery duration, total perioperative fentanyl
dose.
-Similar morphine use, VAS pain scores.
-They compared total N+V incidences between groups
Incidence   Group 1   Group 2   Group 3
0-2 hrs          15%         45%        53%
2-24 hrs        25%         28%        55%
-Also, looked are need for rescue antiemetics
Rescue    Group 1   Group 2   Group 3
0-2 hrs        8%          30%        35%
2-24 hrs     13%         15%        38%