ADDITIONAL SUMMARY OF FINDINGS [Explanation]
| Acupoint P6 stimulation versus sham to prevent postoperative nausea and vomiting | ||||||
| Patient or population: patients with a desire to prevent postoperative nausea and vomiting | ||||||
| Settings: Surgery | ||||||
| Intervention: Acupoint P6 stimulation versus antiemetic | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of Participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| Control | Acupoint P6 stimulation versus sham | |||||
| Nausea - All antiemetics combined | Low risk population1 |
RR 0.82 (0.6 to 1.13) |
660 (9) |
⊕⊕⊕○ moderate2 |
||
| 100 per 1000 |
82 per 1000 (60 to 113) |
|||||
| High risk population1 | ||||||
| 400 per 1000 |
328 per 1000 (240 to 452) |
|||||
| Vomiting - All antiemetics combined | Low risk population1 |
RR 1.01 (0.77 to 1.31) |
1036 (14) |
⊕⊕⊕○ moderate2 |
||
| 100 per 1000 |
101 per 1000 (77 to 131) |
|||||
| High risk population1 | ||||||
| 400 per 1000 |
404 per 1000 (308 to 524) |
|||||
| Rescue antiemetic | Medium risk population |
RR 0.82 (0.59 to 1.13) |
527 (7) |
⊕⊕⊕○ moderate2 |
||
| 180 per 1000 |
148 per 1000 (106 to 203) |
|||||
| Adverse effects3 | 633 per 1000 |
298 per 1000 (165 to 551) |
RR 0.47 (0.26 to 0.87) |
60 (1) |
||
The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).
CI: Confidence interval; RR: Risk ratio;
GRADE Working Group grades of evidance
High quality: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality: We are very uncertain about the estimate.
No risk factors for postoperative nausea and vomiting typically have control rates of 10%; most studies in this systematic review had high risk patients with two or more risk factors for postoperative nausea and vomiting, therefore we assumed a risk of 40%.
Total number of events is less than 300
Restlessness was more frequent after droperidol group than after acupuncture.