The purpose of this review was to evaluate literature related to the efficacy of sensory modification in relieving pain and anxiety and promoting comfort during medical procedures and hospital stays as an alternative to pharmacological management.
Methods: A single researcher conducted individual searches using OVID, CINAHL/EBSCO, and PubMed. Several keyword combinations were used, but those yielding usable results were procedure, noise, ICU, light, surgery, pain, and anxiety reduction. Inclusion criteria included English language, human subjects, free full text, clinical trial, and date range including only those articles published within the last five years. After application of criteria, 15 topic relevant studies were located. All studies reviewed were randomized controlled trials (RCTs). All but eight studies were rejected as they involved sample populations that were either children or undergoing dental procedures. These eight RCTs were retained for this review.
Of the seven RCTs examined, six reported significant reduction in pain and anxiety with sensory modifications of mixed modality. These included earplugs, eye masks, music intervention, and therapeutic touch. Two RCTs examined the addition of earplugs and eye masks to care routines in intensive care and postoperative units during nights following surgery in order to reduce anxiety and physiological stress for patients during their stay. The study by Hu et al was a prospective single-center randomized controlled parallel-group clinical trial. Using the closed envelope method, 45 patients were randomly assigned to either an intervention group or control group. Earplugs and eye masks were provided to the experimental group for three days prior to surgery. Control group received usual care. Subjective sleep perception was evaluated by self report. Nocturnal melatonin and cortisol levels were measured one day prior to surgery and for two days following surgery. Nocturnal noise and light levels were measured in the ICU beginning when patients arrived on the unit following surgery. Mean +/_ standard deviation were used to express measurement data and ratios were used to express count data. An independent samples t test was used for comparison of the intervention and control groups. The chi square was used to compare count data. One way ANOVA was used to express differences in cortisol and 6 SMT over time. Cronbach’s alpha of 0.05 was significant. This study indicated that eye masks and earplugs are effective in reducing disturbance in sleep that can lead to anxiety. In the study be Le Guen et al, 41 patients were randomized into an intervention group receiving earplugs and eye masks on the first night after surgery or a control group receiving routine care. Sleep quality was evaluated by self report, actigraph placed on nondominant wrist, and external assessment by a nurse. For this study, all data are expressed in terms of mean, median, or percentage. MANOVA with P<0.05 considered significant was used to compare each night’s data while in unit. This study suggests that eye masks and earplugs preserve sleep quality and may reduce anxiety.
Another three studies looked at the effect of music therapy via headphones and either CD or MP3 players on perceived anxiety of patients undergoing medical treatment. The study by Eckhouse et al was a pretest/posttest study in which 112 patients were randomized into three groups. One group received usual care before during and after treatment. The remaining groups received either music focused relaxation via headphones and compact disc (CD) during treatment or viewed a 20 minute music video during treatment. One way ANOVA and paired t tests were used to compare patient characteristics and pre and posttest scores. P=0.05 was considered significant. There were no statistical differences between scores of each group to suggest that audio or visual intervention was more effective in reducing anxiety. In the study by Chlan et al, 373 ICU patients were randomized into a control group receiving usual care, a group receiving noise abating headphones, or a group receiving self directed music therapy. Anxiety was measured using daily anxiety assessment and measures of sedative intensity and frequency. Repeated measures ANCOVA was used to measure anxiety and sedative exposure. Significance level was set at p</-.05. Results showed that anxiety and sedative exposure was most reduced by self directed music therapy. In the study by Palmer et al, 207 patients undergoing breast surgery were randomly assigned to receive patient directed live music preoperatively with therapist directed recorded music intraoperatively, recorded music selected by patient preoperatively and selected by therapist intraoperatively, or usual care preoperatively with noise blocking earmuffs intraoperatively. Anxiety was measured by self report and propofol required during surgery. With a significance level of p<.001, one way ANOVA showed a greater reduction in anxiety scores, but not in the amount of propofol required for anesthesia.
The remaining studies explored the impact of preoperative physical conditioning prior to surgery or therapeutic massage prior to surgery on pain and anxiety of patients undergoing surgery. The study by Rosenfeldt et al randomized 117 cardiovascular surgery patients in two groups. The first group received usual care while the second received what was termed holistic care involving physical conditioning for two weeks prior to surgery and mental stress reduction. Outcomes were measured via self report using theShort Form 36 item Health Survey Questionnaire and medical records to assess length of stay. Chi square and Fischer’s exact tests were used for continuous variables and parametric data were analyzed with the student’s t-test. Two way repeated ANOVA was used to compare variables with repeated measures. Results were not statistically conclusive, but further research was warranted. The study by Braun et al examined the effect of massage therapy on anxiety and pain levels in cardiac surgery patients. A total of 152 patients were randomized into two groups that received wither massage or rest after surgery. Visual analog scales (VAS) were employed to assess levels of pain and anxiety both before and after each intervention. Fischer’s exact test was used to examine proportional differences between groups. Repeated measures ANOVA was used to assess changes in VAS scores. Massage significantly relieved pain and anxiety when performed on day 3 or 4 postoperatively (P<.0001). The study by Peng et al also looked at the effect of massage on anxiety in patients receiving percutaneous coronary intervention. A total of 117 participants were randomized into two groups receiving either massage of head, neck, shoulders, and back for 20 minutes before surgery or usual care. Blood pressure, heart rate, and anxiety levels were assessed and compared. Anxiety levels were measured via the State Trait Anxiety Inventory (STAI). The groups were compared using the t-test for independent samples. Comparisons within groups were obtained using a paired t-test. Comparisons of indicators of pain and anxiety were compared between groups using repeated measures ANOVA. Results showed significant reduction in anxiety levels in those patients receiving massage therapy. Self reported anxiety, heart rate, and blood pressure were notably lower in the experimental group. Significance level was p<0.05.
According to studies, compared with groups of patients receiving no environmental sensory modifications, patients undergoing medical procedure in sensory controlled environments experienced more positive outcomes. These outcomes include reduction in anxiety, decreased perception of pain, and improved sleep quality. Addition of complementary therapies to usual care for those patients who are hospitalized or undergoing treatment offer an easy, inexpensive way to reduce anxiety and pain without the side effects of pharmacological management.