Aromatherapie beim vollständigen Knieersatz

This is the interventional group. Participants in this group will receive aromatherapy tabs in the scent of lavender-peppermint. Tabs will be worn on a badge for a total of 72 hours, and participants will replace the aroma tabs every 12 hours.

100% pure essential oils Lavender-peppermint aromatabs purchased through Beekley Medical

This is the placebo group. Participants in this group will receive aromatherapy tabs in the scent of almond oil. Tabs will worn on a badge for a total of 72 hours, and participants will replace the aroma tabs every 12 hours.

100% pure essential oils Almond-oil aromatabs purchased through Beekley Medical

To assess the change in participants' anxiety level before and each individual day after surgery. Measured using the State-Trait Anxiety Inventory (STAI).

STATE anxiety, with higher scores being worse:

For calm, at ease, relaxed, steady:

4 = not at all 3 = somewhat 2 = moderately so

1 = very much so

For tense, worrying over misfortunes, frightened, nervous, jittery, worried:

1. = not at all
2. = somewhat
3. = moderately so
4. = very much so

TRAIT anxiety, with higher scores being worse:

For self satisfaction, feeling secure, being steady:

4=almost never 3=sometimes 2=often

1=almost always

For nervous/restless, wishing to be happier, feeling like a failure, worrying too much, lacking self confidence, feeling inadequate, feeling tension:

1. almost never
2. sometimes
3. often
4. almost always

STAI is scored as a sum of the scores for state and trait, with 20 being the lowest score (better outcome) and 80 being the highest score (worse outcome).

To assess participants' preoperative (cumulative 7 days before surgery) and postoperative (cumulative 7 days after surgery) anxiety. Measured using the PROMIS anxiety short form 8a Version 1.0. Scored on the following scale:

1. = never
2. = rarely
3. = sometimes
4. = often
5. = always with 1 being the lowest score and 5 being the highest scores.

PROMIS anxiety short form 8a Version 1.0 is scored by calculating the sum of the scores for each question, and using the PROMIS conversion matrix to report the T-score (The T-score is a standardized metric where the United States general population mean is set to 50 with a standard deviation (SD) of 10. Higher T-scores indicate greater levels of anxiety.)

To assess the average pain score of participants after surgery. Measured using the numerical rating scale (NRS). Measured on a 11-point numeric scale from '0' representing one pain extreme (e.g. "no pain") to '10' representing the other pain extreme (e.g. "pain as bad as you can imagine" or "worst pain imaginable").

To assess participants' post-operative emotional distress. Measured using the PROMIS depression short form 8a. Scored on the following scale:

1. = never
2. = rarely
3. = sometimes
4. = often
5. = always with 1 being the lowest score and 5 being the highest scores.

Scored by calculating the sum of the scores for each question, and using the PROMIS conversion matrix to report the T-score. (The T-score is a standardized metric where the United States general population mean is set to 50 with a standard deviation (SD) of 10. Higher T-scores indicate greater levels of anxiety.)

The Pain Catastrophizing Scale is made up of 13 phrases that describe various thoughts and sensations that people may have while they are in pain. The items are assessed on a 5-point scale and are grouped into three categories: rumination (4 questions), magnification (3 questions), and helplessness (6 questions). Scored on the following scale:

0 = Not at all

1. = To a slight degree
2. = To a moderate degree
3. = To a great degree
4. = All the time with 0 being the lowest and 4 being the highest score.

Scored as the sum of all questions, and the sum of the scores for each question within each subscale. The range for Total Sum: 0 to 52, Rumination: 0 to 16, Magnification: 0 to 12, Helplessness: 0 to 24

The PROMIS SF v1.1 Pain Interference instruments (adult) measure the self-reported consequences of pain on relevant aspects of a person's life and may include the extent to which pain hinders engagement with social, cognitive, emotional, physical, and recreational activities. Pain Interference also incorporates items probing sleep and enjoyment in life, though the item bank only contains one sleep item. The Pain Interference items utilize a 7-day recall period (items include the phrase "the past 7 days"). Scored on the following scale:

1. = Not at all
2. = A little bit
3. = Somewhat
4. = Quite a bit
5. = Very much With 1 being the lowest and 5 being the highest

Scored by calculating the sum of the scores for each question, and using the PROMIS conversion matrix to report the T-score. (The T-score is a standardized metric where the United States general population mean is set to 50 with a standard deviation (SD) of 10. Higher T-scores indicate greater levels of anxiety.)

Self-reported measure of medication, dosage, and time of opioid consumption. Reported as Morphine Milligram equivalents.

To assess if participants experience post-operative nausea. Measured using the Opioid Related Symptom Distress Scale question: In the past 24 hours, I had nausea (yes/no).

To assess if participants experience post-operative vomiting. Measured using the Opioid Related Symptom Distress Scale question: In the past 24 hours, I had vomiting (yes/no).

To assess the incidences of post-operative complications such as need for ICU admission, DVT/PE, MI, stroke.

To be measured in the number of patients who reported adverse events.

The Opioid-Related Symptom Distress Scale (ORSDS) assesses opioid-related symptoms across the dimensions of frequency, severity, and bothersomeness. According to the scoring manual, Clinically Meaningful Events (CMEs) are calculated using the symptom severity items only. Severity is rated on a 5-point scale ranging from 0 (did not have symptom) to 4 (very severe). Therefore, scores range from 0 to 4, with higher scores indicating greater symptom severity.

Self-reported responses on a survey of 7-items to assess participants' level of satisfaction with the aromatherapy they received.

Measured on the following scales:

1. = Not satisfied/no prior knowledge or experience/ not at all/ no
2. = A little bit/a little knowledge or experience/to a slight degree
3. = Moderately/moderate knowledge or experience/to a moderate degree
4. = Quite a bit/considerable knowledge or experience/to a great degree
5. = Extremely satisfied/expert knowledge or regular application/all of the time/ yes with 1 being the lowest and 5 being the highest.

Feasibility was assessed as the number of Participants that reported "Yes" to wearing each aromatab.

Hospital length of stay was measured as hours elapsed from post anesthesia care unit entry to discharge, assessed up to 7 days.

The Bang Blinding Index ranges from -1 to 1, where index of 0 indicates random guessing (perfect blinding, better outcome), 1 indicates complete unblinding (all guesses are correct, worse outcome), and -1 indicates complete opposite guessing (all guesses are incorrect, worse outcome). Patients were asked to guess whether the patient was given the intervention (Lavender-Peppermint) or Control (Almond Oil) Aromatherapy. For each arm, calculation of the index score involves subtracting the proportion of respondents assigned to that arm who guess incorrectly from the proportion that guessed correctly.