Listening to music may relax mechanically ventilated patients, but there are limitations to the quality of the available evidence
- Correspondence to Ulrica Nilsson
Department of Nursing, Umeå University, SE-901 87 Umeå, Sweden;
Implications for practice and research
▪ Music interventions may have a beneficial effect on heart rate, respiratory rate and state anxiety in mechanically ventilated patients.
▪ Randomised controlled trials (RCTs) following the CONSORT statement with sufficient sample size and well-established outcome measures are needed in testing music interventions.
The intensive care unit (ICU) environment is a strange place with its noises, equipment, constant activity and bright lights. The demands of critically ill patients in this environment often keep the care providers from recognising the hostility of the environment from the patient's perspective. Patients are often scared, confused and uncomfortable, and the ICU environment does little to provide comfort. Enhancing comfort leads to increased perceptions of well-being and decreased perception of stress.1 The majority of ICU patients are mechanically ventilated. Mechanical ventilation often causes major distress and anxiety in patients, putting them at greater risk for complications. Side effects of analgesia and sedation may lead to the prolongation of mechanical ventilation and, subsequently, to a longer length of hospitalisation and increased cost. One way to lower the stress level is to provide distractions for the patient. Music intervention is one form of distraction that can be performed in the ICU with minimal intrusion into environment.
In this systematic review, Bradt and colleagues conducted a methodological search for RCTs and quasi-RCTs with no language restriction published from first available date to January 2010. Systematic searches were performed in Cochrane Central Register of Controlled Trials, MEDLINE, CINAHL, AMED, EMBASE, PsycINFO, LILACS, Science Citation Index, http://www.musictherapyworld.net, CAIRSS for Music, Proquest Digital Dissertations, ClinicalTrials.gov, Current Controlled Trials, the National Research Register and NIH CRISP databases. The authors also hand searched music therapy journals and reference lists and contacted relevant experts to identify unpublished manuscripts. Studies were included if they compared music interventions and standard care with standard care alone for mechanically ventilated patients.
A total of eight RCTs and quasi-RCTs published in English between 1995 and 2007 were included, with a total of 213 participants. Seven studies included prerecorded sedative or calming music and one study used live music, offered in one 20–60 min session to patients. Seven studies used patient-selected music. Where patients were unable to select music, the patient's family or friends performed the selection. One study used researcher-selected music. In general, the quality of the included studies was poor because of small sample size, methods of randomisation and allocation concealment and level of blinding. The authors had to contact the chief investigators of most of the studies for methodological and statistical information. Despite this additional information, five studies received a high risk of bias rating, two a moderate risk and only one a low risk. However, the findings of the present review suggested that music listening has a beneficial effect on heart rate, respiratory rate and state anxiety in mechanically ventilated patients. No evidence of effect was found for blood pressure or oxygen saturation level.
In this well-conducted systematic review, the studies included were concisely and accurately summarised, and the data synthesis was accurately reported. For nurses and other health professionals, this review does provide evidence that sedative and calming music has a beneficial effect on heart rate, respiratory rate and state anxiety in mechanically ventilated patients. Florence Nightingale proposed that it was the responsibility of nursing to control the patient's environment in order for healing to take place, and she recognised the power of music as a part of the healing process. Descriptions of music perceived as relaxing are as follows: ‘quiet’, ‘peaceful’, ‘soft’, ‘dreamy’, ‘soothing’, ‘serene’, ‘undramatic’, ‘slow speed’, ‘regular rhythm’, ‘pleasant combination of instruments’ and ‘low volume’.2 There is currently no evidence regarding which genre is superior or whether researcher-selected versus patient-selected music is most beneficial. In the present review, seven out of eight patients used patient-selected music. The mechanism behind the effect of relaxing music is not clearly understood. It has been reported that the relaxing effect of music is related to an increased release of plasma oxytocin3 and a reduction in plasma cytokine and catecholamine levels.4 Evidence also suggests that music listening modulates emotional arousal as indexed by changes in cardiovascular and respiratory activity5 as well as directs attention away from negative experiences, thus helping an individual to cope with emotional stress.6
Although the present review finds a small effect of sedative and calming music, music listening is a nursing intervention that has an obvious role in the care of mechanically ventilated patients. Music intervention is an inexpensive technique, which does not require the use of extra staffing and resources, and it provides the patient with distraction from the stressful ICU environment. Essential elements of music intervention are a quiet environment, a comfortable position, dimed lights and a willingness to participate in this type of distraction. It is desirable that a music therapist collaborates with staff in providing music interventions, in addition to performing an accurate assessment of patients' musical preferences. Furthermore, there is a need to assess, evaluate and document the effect of the intervention.
In conclusion, the results of this review are consistent with previous systematic reviews on music interventions, which have also found some improvements in stress reduction including heart rate, respiratory rate, anxiety, pain, analgesic use and sedative use. Unfortunately, the quality of the available studies has been poor. Although the authors scrutinised their search, including 15 databases and hand searching, only eight studies were found. This emphasises that testing of music intervention needs to continue, particularly through RCTs with sufficient sample size and well-established outcome measures and, last but not least, following the CONSORT statement.7