TITLE Is it feasible to use essential oils to reduce perioperative patient anxiety? Experience from a randomised trial. OR Can Essential Oils reduce perioperative patient anxiety Prof GILLIAN RAAB Prof BETH ALDER PhD C Psychol LAURA STIRLING MSc RGN RSCN RNT LLSA Lecturer Napier University School of Nursing, Midwifery and Social Care 74 Canaan Lane EDINBURGH EH9 2TB 0131 455 5665 l.stirling@napier.ac.uk 1 ABSTRACT Aim This paper reports a study examining the effectiveness of essential oils in reducing anxiety in thoracic patients awaiting the results of investigative and staging surgery. Background Patient anxiety is expected during the perioperative period. Evidence suggests that anxiety places the patient at greater risk of adverse clinical outcomes. Nurses are not unfamiliar with this but are limited in therapeutic options that can be used to address anxiety in the limited time available. Complementary therapies have been tested for therapeutic benefit but the evidence is weak. Method Patients admitted to a thoracic unit for bronchoscopy/mediastinoscopy (BS/MS) were invited to participate in this double-blind controlled trial and randomised to receive study oil (A), neutral oil (B) or no intervention (C). Intervention was controlled by the patient at home after BS/MS. State Trait Anxiety Inventory (STAI) and Hospital Anxiety and Depression Scale (HADS) tools measured baseline and periodic anxiety status (Day 3, 21). Results Of the 142 patients approached to take part in the study, 71 (50%) agreed to take part. There were high levels of perioperative anxiety in the thoracic 2 patient group, but no evidence that it was reduced by the absorption and inhalation of essential oils. Conclusion The study did not provide evidence that the essential oils could reduce anxiety in this group of patients. Both recruitment rates and compliance rates were lower than anticipated. Logistic factors in the setting of diagnostic process for an acute condition may have contributed to these results. Key Words: Surgical Nursing; Anxiety; Anxiety measurement; Clinical Effectiveness; Complementary Therapies; Essential oils 3 SUMMARY STATEMENT What is already known about this topic: Failure to reduce perioperative anxiety can lead to physical and psychological problems Time to address patient anxiety effectively in clinical practice is often limited Essential oils are a popular form of complementary therapy with nurses and patients, but evidence of their effectiveness is weak What this paper adds: Patients undergoing investigative surgery have high levels of anxiety. Scientifically rigorous research, both in the field of nursing and aromatherapy is required to improve the patient experience. 4 REDUCTION OF PERIOPERATIVE ANXIETY USING ESSENTIAL OILS INTRODUCTION Traditionally, anxiety management has involved the amalgamation of medical intervention and communication strategies. Anxiety has been shown to place the patient at increased surgical risk (Kanto 1996), delay wound healing (Glaser et al 1999), prolong hospitalisation (Boeke et al 1992) and increase morbidity and mortality (Frazier et al 2003). Complementary therapies have been tested for therapeutic benefit in the relief of anxiety/stress, but the evidence is weak. Recommendation to develop research in this area was made in the House of Lords report on complementary and alternative medicine (CAM) (DoH 2001) and scientifically rigorous research is now increasing. In 1996, Trevelyan reported that 50% of nurses used at least one form of CAM in their practice and since then, their popularity has continued to increase across the professional population (Godfrey 2003) as well as amongst the general public (Avis 1999). Nurses have documented the use of aromatherapy or essential oil (EO) use with patients (Ersser 1995; Cole and Shanley 1998), yet this, in many cases, has been in conjunction with massage and the effectiveness of oils alone has not been widely researched. EOs have the potential to alleviate anxiety in a variety of ways, but this potential might equally well have the opposite effect. As chemicals, essential oils carry risks if used by the inappropriately educated and qualified. The study oils selected have chemical profiles that determine antidepressant, anxiolytic and tonic properties. Citrus Aurantium (neroli/orange blossom), with high 5 proportions of terpenic alcohols, hydrocarbons and esters and Santalum album (Sandalwood), with sesquiterpenic alcohols and esters (Harris, 2006) between them also form a blend posing little, if any irritant potential. Patients awaiting the results of investigative bronchoscopy/mediastinoscopy (BS/MS) for whom inoperable cancer is a possible diagnosis, are highly anxious (Shearer and Davidhizar 1998). They contend not only with the worry of waiting for results, but with the chance that they may have inoperable cancer. Some will also worry about the risks of major surgery and anaesthesia, should future surgery become an option. Nurses will be in a better position to offer advice to the patient on the use of essential oils at home, if the evidence of safety and effectiveness is available to inform their practice. This paper describes a Chief Scientist Office funded feasibility study of a nurse-led intervention for patients with lung lesions who awaited the results of investigative BS/MS. The proposed treatment evaluated in the study was the inhalation and absorption of an essential oil blend of neroli (Citrus Aurantium) and Sandalwood (Santalum Album), both considered to have anxiolytic properties. Literature review Hollaus et al (2003) reflect that pre-operative anxiety is inherent to surgical patients, irrespective of diagnosis. According to Salmon (1993), it is normal to view anxiety as an unwanted patient problem despite the fact that it is a human behaviour necessary to prepare the body psychologically and physically to face a threat or challenge. In his view, anxiety should not be so 6 far reduced that a patient loses his ability to cope with the challenge. Yet, anxiety has proven disadvantages for the patient, which can cause poorer outcomes of various types (Johnston 1986). There is ample evidence that anxiety in the perioperative patient puts them at greater anaesthetic or surgical risk (Kanto, 1996; McCleane and Cooper, 1990). Anaesthetic and intra-operative requirement can be influenced by anxiety (Williams et al, 1972; Lindgren et al 1980; Kindler et al, 2000;) and trait anxiety specifically has been shown to predict intra-operative needs (Maranets and Kain 1999). Boeke et al (1991) and Kindler et al (2000) found that post-operative recovery can be hampered in a number of ways as a result of high preoperative anxiety. These might include reduced ability to resist infection (Fyfe 1999), increased need for post operative analgesia ( Linn et al 1988; Munafo and Stevenson 2001), delayed wound healing (Kiecolt-Glaser et al, 1995) influences on patient mood (Munafo and Stevenson, 2001), and increased stay in hospital (Boeke et al, 1992; Linn et al, 1988). From the evidence, it appears that there is considerable rationale for trying to relieve anxiety in the surgical patient. In Mitchell’s (2000) opinion, psychological care remains a lesser priority than physical assessment both pre and post-operatively. Modern technology and services have meant that many patients are suitable for short term surgery. Cahill (1999) suggests that this increased patient turnover has put physical care demands higher on the nursing care agenda than the management of psychological needs. The pace of work, whether within ward or community settings and the lack of time to address emotional needs, frustrates nurses (Avis 1999). Kain et al (2000) argue that interventions to reduce patient 7 anxiety are diminishing for mainly financial reasons, yet it remains an aim of most nurses (Mitchell 2000) to promote well-being and independence in their patients. Few alternative strategies for the management of pre-operative patient anxiety reduction are documented within nursing texts. Strategies such as music therapy (Lepage et al 2001; Cooke et al 2005), watching television and the use of relaxation tapes have been considered as alternatives to medication or face to face communication, but little reliable evidence exists that they work effectively. THE STUDY Aim To carry out a pilot study for single centre randomised double blind, parallel group controlled trial of the effectiveness of essential oils in reducing anxiety in patients with lung lesions who awaited the results of diagnosis and staging from bronchoscopy/mediastinoscopy. Design Patients admitted for BS/MS were approached by a research assistant (RA) on the day of admission and given information about the study. Those who had taken anxiolytic or antidepressant medication within the last two weeks were excluded. Consenting patients were randomly allocated to receive either the essential oil (neroli/sandalwood) blend (a), a neutral oil (B; Linden flower oil) or to receive no intervention (C). Randomised treatment allocations were placed on cards in sealed envelopes which were opened after 8 measurement of baseline anxiety levels using the STAI and HADS tools. Where there was assignment to an oil intervention, the card indicated the number of the bottle to use, with the bottle containing the oil corresponding to the randomisation sequence. No oil bottle was opened in the presence of the research assistant to preserve ‘blindness’. Participants receiving oil were given simple safety and usage information before going home. A minimum amount of oil to use (application to skin) per day was advised as 5mls twice daily, but the control over the actual usage was the participants’. Oils were to be used for 21 days after discharge from BS/MS where possible. The primary outcome measure was the change in the score on the State component of the State Trait Anxiety Inventory (STAI). Power calculations were based on data from breast cancer patients where the standard deviation of changes in the STAI scores was found to be 1.3 points (Gray et al 1999). With these assumptions, a sample size of 30 in each study arm would give 85% power to detect a 1 point difference in the change in score between two arms of the trial. Ethical approval to conduct the study was granted by the Lothian Research and Ethics Committee and by the research and development committee of the study hospital. Data Collection At recruitment, demographic data and experience and knowledge about essential oils was recorded and the patient completed their first STAI measure and the HADS. The latter was used to assess the severity of anxiety and depression without contamination of scores by physical symptom reports. 9 Participants were asked to complete further Trait component questionnaires (STAI-S) on day 3 and day 21 and return them to the RA in pre-paid envelopes from home. As a measure of compliance, participants were asked to complete a one-page diary (outlining oil use and any free comments each day) and to return the bottle at the end of 21 days. Data Analysis Comparisons between randomised groups were carried out on an intention to treat basis. The analysis of the main outcome (STAI-S at follow up) was by analysis of covariance adjusted for covariates measured at baseline, including the baseline level of STAI-S. Results are presented as adjusted differences between treatments. This approach is known to be more efficient in analysing differences from baseline. Comparisons of means were carried out by t-tests and proportions were compared with chi squared tests, with Yates correction. Results Recruitment began in February 2005 and within 12 months 146 patients were approached, of which, 71 ( male n = 42; female n = 29) consented to participate (Figure 1). Significantly more participants were younger patients (p <0.01), but there were no gender differences in participation (Table 1). Baseline data were well balanced by allocated treatment. Forty participants completed the study. Of the 31 who did not, 22 had surgery close to receiving the BS/MS results (3 died post-operatively) and 6 were referred for oncology treatment. Two others withdrew within 2 days of recruitment without 10 explanation and one remaining participant withdrew because of dislike of the oil aroma. Group C had a slightly higher return rate but there were no significant differences by treatment (Figure 1). Age and gender did not influence the probability of the STAI-S return. Table 3 gives the means and differences of the STAI-S scores for all patients from whom results were obtained at any time. Those patients who returned day 3 and day 21 results did not differ significantly in STAI-S from those who did not. Mean values were similar to the norm for surgical patients (42.68; Spielberger 1983) in 47 of the participants and higher than the stated norm for working adults aged 50 – 69 years (male 34.51; female 32.20). The values and differences of the STAI-S scores were highly variable between patients. Figure 2 shows the relationship between day 3 scores and day 0 scores. Although there is a clear relationship (r = 0.66, p<0.001) there were also many patients with large differences between the scores on the two occasions. Table 4 compares the main outcome at days 3 and 21 by randomised group. There were no significant differences between treatments and all the confidence intervals for the treatment differences were very wide. As expected, the confidence intervals for the adjusted values, the main analysis specified, were narrower than for the unadjusted differences, but they were still much wider than was expected at the time of planning the study. All the baseline measures (STAI and HADS) were predictive of the outcome taken one at a time, but in a multivariate analysis only STAI-S was significantly predictive at day 3, while STAI-S, HADS-A and HADS-D were predictive of outcome at day 21. Forty eight of the 71 participants were allocated an oil (A or B), of which 34 returned bottles containing the remaining contents at the 11 end of their participation. Of those received, six contained the full 300ml volume. Of these, one participant had liked the aroma, two had not (and withdrew because of this) and three reported inability to detect the aroma due to a poor sense of smell. Twenty eight participants had used oil, of which nineteen used between 10 and 100 mililitres (mls). Seven used between 101 – 200 mls and two used over 200mls. Of the oil users, 17 liked the aroma, 4 disliked it and 7 could not detect an aroma or were ambivalent about it. Of those who did not return bottles (n =14), two did go on to complete the study and return diaries. Eight participants had liked the aroma; six had been unable to detect any aroma or were ambivalent about it. It might be concluded that it is unlikely that aroma was an influence in completion of the study. Eleven of these participants had surgery and five were referred to oncology because of inoperable diagnosis. Discussion Summary points This study was unable to show any differences because of Poor recruitment Poor follow up Poor compliance Volatility of outcome measures over this difficult period, hence reduced power compared to planning. 12 The primary aim of the study was to investigate whether a randomised controlled trial to test the effectiveness of essential oils in reducing anxiety would be feasible. It was anticipated that about 200 patients would be available for approach in the thoracic ward, with the goal to recruit 100 consenting participants. One of the four Consultant surgeons refused access to his patient group and the potential was reduced. The refusal rate of possible participants was higher than expected. This might have been because of already heightened anxiety levels or because many were over 60 years old (91% female; 85% male). There were no differences in gender distribution between participants and non-participants. During the recruitment process, no information about who was to be admitted for BS/MS was available until the Friday of the preceding week. Patients arriving on a Sunday, for Monday procedure, had no time to receive and read the study information sent by post on the Friday and thus had less time to reflect upon their decision to participate once the Research Assistant had spoken with them in the ward. Patients admitted Monday to Wednesday had received postal information and had had time to consider their participation. As the turn around from the invitation to attend for BS/MS and the actual admission is so short, there is no ideal recruitment solution. Completion of both study questionnaires (STAI and HADS) proved difficult for a few participants and formed the longest part of the recruitment process. Even with clear instructions, many required additional assistance. Telephone calls to participants served as reminders to them to complete the STAI-S at days 3 and 21. Although recruitment was healthy during the Christmas fortnight, drop-out was high. Given the time of year, many recruited were 13 brought from results of BS/MS stage to admission for surgery more quickly. This perhaps accounts for some of the drop-out. Forty participants completed the study. Amongst those who did not, 22 had had major surgery between the day 3 and day 21 period and 6 had had to face the reality that surgery was not feasible (associated with poorer longterm outcome). Either or both of these issues may have influenced drop-out rate. In terms of aroma, the project oils were aesthetically acceptable to most of the participants. Of 48 who received an oil, 26 said that they liked it, whilst 14 declined to comment. Eight disliked the oil. Although bottle return and the amount of oil used was taken as a measure of compliance with the study, this may not have been reliable. A participant was free to return any amount of oil. The return of full bottles of oil may not be explained completely in terms of dislike of aroma as of those who did so, more liked than disliked the aroma. STAI-S scores were similar to the norm for surgical patients (42.68; Spielberger 1983) in 47 of the participants and higher than the stated norm for working adults aged 50 – 69 years (male 34.51; female 32.20) (Table 3). As found in other studies, this demonstrates that these patients are very anxious in the pre-operative period. State anxiety score for day 0 was a strong predictor of state anxiety scores on day 3 and in half of the sample, day 21. The day 3 STAI-S scores show a slight but significant increase in STAI-S score. It is suggested that the assessment of state anxiety at day 3 is too early and on day 21, based on the drop-out rate, is too late. Selection of day 3 for STAI-S completion was considered appropriate as no patient would have yet received their results and therefore were at a similar stage of experience. However, in that 3 day period, a patient is post-operative and may have pain 14 or sleep disturbance, both factors that might influence perceived anxiety. It could be said then that a rise in anxiety scores between baseline and day 3 might be expected. In the period between day 3 and day 21, participants had received results of BS/MS and many were imminently pre-operative ( 1 – 5 days) or were post-operative (1 – 15 days). It is possible that, some who consented to participate in December had not taken Christmas into account. Choosing an appropriate point for collection of data beyond 3 days in this participant group was difficult and the results confirm that 21 days was not suitable. Conclusions The study results were not able to show that essential oils reduce anxiety for the reasons discussed above. However, given that this target population has a high baseline anxiety score, the potential for such an intervention to reduce anxiety in such a short time-span may be limited. Using this data collection method, a larger clinical trial to test the effectiveness of essential oils in reducing anxiety in this patient population might not be feasible. The study identifies that perioperative surgical patients are anxious and that there are difficulties in using them within clinical studies. A different patient population with anxiety scores that are more stable would be more suitable for evaluating the effectiveness of essential oils at reducing anxiety. 15 All By age group Number Total agreed % 145 71 49.0% pvalue 59 and under 60-69 70-75 75 and over By gender male 29 45 43 28 22 20 19 10 82 42 51.2% 0.53# female * mantel-haenzel test for trend # chi square test 63 29 46.0% Table 1 Participation rates by age and gender 16 75.9% <0.01* 44.4% 44.2% 35.7% Table 2 : Baseline comparisons, all randomised Groups No Oil (C) (n=23) Gender Baseline Scores Male Female Smokers Age STAI anxiety State STAI anxiety Trait HADS-A HADS-D Oil Blend (A) (n=24) Neutral Oil (B) (n=24) n 15 8 19 % n 14 10 15 % n 13 11 17 % Mean 66.0 SD 9.5 Mean 62.0 SD 8.9 Mean 66.0 SD 9.5 44.4 13.1 41.4 14.6 44.2 13.3 36.6 9.2 36.7 9.1 36.6 6.9 9.4 4.3 4.9 2.9 9.0 4.5 5.2 3.6 9.7 4.4 4.7 3.2 17 Table 3 : Mean scores and differences for STAI-S All patients (n=71) Day 0 Day 3 Day 21 differences Day 3 – day 0 Day 21 – day 0 mean 43.28 SD 13.57 Patients with STAI-S at day 3 (n=52) mean SD 42.17 12.50 43.87 11.79 1.69 10.03 Patients with STAI-S at day 21 (n=38) mean SD 41.76 12.65 43.71 11.53 43.95 11.83 1.95 2.18 9.67 10.70 Table 4 : STAI-S treatment comparisons Treatments n STAI-S Day 3 mean 95% CI n STAI-S Day 21 mean 95% CI No oil (C) Oil blend (A) Neutral oil (B) 19 17 42.26 46.06 17.7 21.83 67.36 70.29 16 11 43.13 44.45 12.68 28.00 73.57 60.91 16 43.44 21.66 32.66 11 44.64 24.53 30.16 3.80 2.62 1.17 -4.16 -5.68 -6.91 11.75 10.92 9.26 1.33 -0.18 1.51 -8.18 -10.54 -8.00 10.84 10.18 11.03 0.89 1.40 -0.52 -5.20 -4.93 -6.25 6.97 7.74 5.21 -2.09 2.52 -4.61 -8.14 -4.20 -10.23 3.97 9.25 1.01 Differences between treatments A–C A–B B-C Adjusted* differences between treatments A–C A–B B-C * Adjustment for baseline STAI-S STAI-T HADS age and gender 18 REFERENCES Avis, A (1999) When is an aromatherapist not an aromatherapist? 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