Table.

Scenario Analysis of Side-by-Side Estimated Incidences of PONV When the Consensus Guidelines Are Followed Versus the Proposed P-D-O Technique

Baseline PONV risk	Consensus-recommended intervention1	Consensus-dosed, PONV cases per 2001	P-D-O technique, PONV cases per 2002,3	PONV prevented with P-D-O, cases per 2002
10%	Wait and see	20	8	12
20%	2 antiemetics	22	16	6
40%	2 antiemetics	45	32	13
60%	3 or 4 antiemetics	25 + 19 = 44	38*	6
80%	3 or 4 antiemetics	34 + 25 = 59	51*	8
Difference in incidence (column total)		190 per 1000	145 per 1000	45 cases per 1000 prevented

P-D-O technique: perphenazine (8 mg orally before surgery) plus dexamethasone (4 mg IV after induction) plus ondansetron (4 mg IV before emergence). When the Consensus-recommended intervention involves a range of options (eg, 3 or 4 antiemetics), the Consensus-dosed PONV cases per 200 represents a weighted average (half receiving 3, the other half receiving 4), ^*but for the P-D-O technique, a fourth agent (eg, aprepitant) is what we recommend (and assume) for all cases to have a 25% further risk reduction. Further prospective study is needed to confirm this clinical impression. In this illustration, oral perphenazine 8 mg² is assumed to be a viable substitute to IV droperidol 1.25 mg³, with a ~25% risk reduction. Further prospective study is needed to confirm this clinical impression. No other multimodal techniques are assumed to have been given in either treatment arm (eg, regional or total IV anesthesia). Based on this estimate, 45 fewer patients per 1000 would encounter PONV with the P-D-O technique, representing a 24% risk reduction when compared with the Consensus guideline prophylaxis scheme using ondansetron-dexamethasone, with or without droperidol, and with or without aprepitant, based on the risk estimate category given above.

Abbreviations: IV, intravenous; P-D-O, perphenazine-dexamethasone-ondansetron; PONV, postoperative nausea and vomiting