Table 2. Effect of perioperative or postoperative aromatherapy on anxiety, stress, pain, nausea, vomiting, and sleep quality*.

Year	Intervention	N	Patients	Surgery	Type/quality	Results
Symptom: Anxiety and stress
2013 (e58)	Bergamot oil vs. placebo (diffuser)	109	Adults	Ambulatory ‧‧surgery	RCT, Q good	Anxiety reduction: −3 vs. −2 pts (p = 0.02)
2014 (e65)	Postoperative inhalation of lavender vs. water	60	Adults	Cardiac surgery	RCT, Q good	Anxiety reduction: −6.13 vs. −5.27 pts (immediate), −7.4 vs. 6.44 pts (3 rd postoperative day)
Symptom: Pain
2014 (e7)	Massage with eucalyptus–lemon oil vs. carrier oil vs. standard	60	Adults	Vitrectomy	RCT, Q good	Pain reduction: shoulder, −1.1 vs. −0.8 vs. 0.15 FPS; neck, −0.85 vs. −0.8 vs. 0.15 FPS; back, −0.75 vs. −0.6 vs. 0.3 FPS; waist, −0.9 vs. −1 vs. 0.1 FPS; arms, −0.85 vs. −0.05 vs. −0.05 FPS
Symptom: Nausea and vomiting
2018 (e1)	Perioperative inhalation of diverse aromatic oils vs. placebo	402	Mixed	Mixed	SR, Q high	Nausea: SMD = −0.22 (95% CI: [−0.63; 0.18]; p = 0.28), antiemetic reduction: RR = 0.60 (95% CI: [0.37; 0.97], p = 0.04)
2016 (e37)	Inhalation of ginger/lavender/menthol vs. NaCl	80	Children (4–16 years)	Ambulatory surgery	RCT, Q good	Reduction of retching: 90% vs. 78%; reduction of antiemetics: 52% vs. 44%; reduction of vomiting: 9% vs. 11%

* The complete table is available on the internet as eTable 2 CI, confidence interval; FPS, Faces Pain Scale; N, sample size; NaCl, sodium chloride saline solution; pts, points; Q, quality determined by AMSTAR score (for SR) or Jadad score (for RCT); RCT, randomized controlled trial; RR, relative risk; SMD, standardized mean difference; SR, systematic review