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Journal of Neuroscience Nursing:
doi: 10.1097/JNN.0b013e3182029778

Use of Music and Voice Stimulus on Patients With Disorders of Consciousness

Giesbrecht Puggina, Ana Cláudia; Paes da Silva, Maria Júlia; Ferreira Santos, Jair Lício

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Author Information

Maria Júlia Paes da Silva, PhD RN, is a full professor at the School of Nursing, University of São Paulo (EE-USP), São Paulo, Brazil.

Jair Lício Ferreira Santos, PhD B, is a biostatistician and a full professor at the Social Medicine Department, Faculty of Medicine of Ribeirão Preto, University of São Paulo (FMRP-USP), São Paulo, Brazil.

Questions or comments about this article may be directed to Ana Cláudia Giesbrecht Puggina, MBS RN, at She is a postgraduate student at the School of Nursing, University of São Paulo (EE-USP), and a professor at the Faculty of Medicine of Jundiaí, São Paulo, Brazil.

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ABSTRACT: The objectives of this study were to check music and voice message influence on vital signs and facial expressions of patients with disorders of consciousness and to connect the existence of patient's responses with the Glasgow Coma Scale or with the Ramsay Sedation Scale. The method was a single-blinded randomized controlled clinical trial with 30 patients, from two intensive care units, being divided into two groups (control and experimental). Their relatives recorded a voice message and chose a song according to the patient's preference. The patients were submitted to three sessions for three consecutive days. Significant statistical alterations of the vital signs were noted during the message playback (oxygen saturation-Day 1 and Day 3; respiratory frequency-Day 3) and with facial expression, on Day 1, during both music and message. The conclusion was that the voice message was a stronger stimulus than the music.

Disorders of consciousness are clinical diagnostic entities where there are diffused psychological losses, most of the time being followed by a generalized reduction or alteration of the consciousness content, added to deficiencies for awakening. Coma, vegetative state, and sedated patients are disorders of consciousness with major clinical differences. Coma and vegetative state occur generally because of brain damage, intoxication, endocrine, and metabolic problems, of which, depending on the severity, the vital functions are maintained in a higher or lower degree (Plum & Posner, 1977). Without centrally acting drugs or sedation, the patient can be measured through the Glasgow Coma Scale (GCS), and with sedation through the Ramsay Sedation Scale (RSS).

The GCS has been used to grade individual levels of consciousness and to compare effectiveness of treatment and as a prognostic indicator (Sternbach, 2000). The scale has three evaluation indicators-ocular opening, verbal response, and motor response, with the total score being derived from the sum of these indicators, which can vary from a minimum of 3 points to a maximum of 15 points. A score lower than 8 points is generally accepted as the critical point of changes in consciousness level and as the score that defines an individual in the state of coma (Koizume, 1990, 2000; Muniz, Thomaz, Kubota, Cianci, & Souza, 1997).

The RSS is a resource applied to evaluate the agitation and the efficiency of the sedation in critically ill patients. There are six stages in total divided into two main levels: awake levels-(1) patient anxious or agitated or both; (2) patient cooperative, orientated, and tranquil; and (3) patient responds to commands only; and asleep levels-(4) a brisk response to a light glabellar tap, (5) a sluggish response to a light glabellar tap, and (6) no response. The last two scores (5 and 6) are related to sedation with small reply and deep sedation (De Jonghe et al., 2000; Schell & Puntilho, 2005).

The responses of patients with disorders of consciousness, in relation to the verbal communication, have always been a subject of controversy, despite the advances in medicine and neuroscience. We still do not have a precise answer to what actually takes place in the mind of the patients during the experience of being in consciousness altered state; however, more studies need to be done to determine other available methods of measuring the responses to auditory stimuli of patients with disorders of consciousness (Ferreira, 2000; Puggina, Silva, Gatti, Graziano, & Kimura, 2005).

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The purposes of this study were (a) to verify the influence of music and voice message on the vital signs and the patients' facial expressions with disorders of consciousness and (b) to relate the existence of the patients' responses using the GCS or the RSS in what refers to music and voice stimuli.

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For verification of the proposed objectives, a single-blinded randomized controlled clinical trial was accomplished (Fletcher, Fletcher, & Wagner, 1996), having as intervention a patient's favorite music and a voice message (independent variables), and as indicators of results, the alterations in vital signs and in facial expressions (dependent variables) were used.

The sample group consisted of 30 patients hospitalized from March to September 2005 in two intensive care units (ICUs) of a hospital school in the city of São Paulo (Brazil) and met the following inclusion criteria: (a) to be with disorders of consciousness; (b) to be evaluated according to one of the scales and to have a score in the study range-without centrally acting drugs or sedation, score between 3 and 8 GCS; with sedation, one of the last two scores of RSS, R5 or R6; (c) to have hearing function preserved according to family; and (d) to have written consent from the family or responsible party for the patient's participation in the research.

After the approval of the ethics committee, the collection of data began (protocol number 1079/04). A family member, for each patient included in the research, received a full explanation of the objective and signed the informed consent.

The selected patients were randomly allocated in two groups, experimental and control, and only the experimental group received the intervention of both music and voice stimuli.

The voice message henceforth referred to as only message was used with two basic objectives: to expose the patient to familiar language stimuli and to attempt to get the patient's attention. Some standardization criteria were used, such as (a) elaboration of the message by a significant relative of the patient because the person who was accompanying them at that moment did not necessarily have a strong bond with them; (b) duration of 3 minutes maximum; (c) to say who is talking at the beginning and repeat it at the end of the message; (d) say at least three times the patient's name during the message; (e) inform the patients where they are and what is happening to them; and (f) tell a message of affection and with an optimistic perspective, saying something about their family life.

The music used in this study was selected by a relative, considering the patient's musical preferences, to offer a stimulus with an affectionate bond and to provide comfort as well.

Two compact discs (CDs) were recorded for each patient; however, only one was used because the study was single blinded to the data collector:

* The CD with the stimuli (preferred music and message-always in this sequence).

* The CD without stimuli (silence and silence-with the same time of chosen music and recorded message). The CD without stimuli was obtained through the recording of silence accomplished with the digital voice tape recorder and later recorded on CD.

Because recording time varied according to the chosen music and the message for each patient, there was no standard time in the research for the duration of the CDs between the patients.

On the basis of this, patients were randomized into two groups, experimental and control. The method used to select patients for this study was a simple random selection. In the experimental group, the CD with stimuli was played, and in the control group, the CD without stimuli (silence) was played. During the sessions, headphones were placed on the patients. The advisor was responsible for the random distribution of the groups, without the data collector's awareness of which CD was chosen, to avoid bias in the interpretation during data collection (single-blinded study). The stimuli volume was between 60 and 70 dB. The evaluation according to GCS and RSS was always accomplished before each session and before any stimulus was applied.

The patients were submitted to three sessions, being accomplished one time per day for three consecutive days. Consecutive days improved the chance of the data being collected with the patient in the same clinical state. The number of sessions was important to evaluate the stimuli influence over the patient's mental state. During the intervention, any manipulation or touch in the patient was avoided.

A data collection form was elaborated. The vital signs were evaluated in three times in each session: (a) baseline, (b) after 60 seconds of music or silence, and (c) after 60 seconds of message or silence. The following were logged in a preestablished sequence as well: pulse, axillary temperature, blood pressure, oxygen saturation, and respiratory frequency. This sequence was established with the practical criteria. All patients, in this research, were monitored with homodynamic monitors.

The facial expressions were evaluated in baseline and during the interventions with video recordings so that no information was lost during data collection. The recordings were accomplished by digital camera for future visualization.

The data analysis was made in the STATA® program, with the intent of comparing the two groups. Comparison of the variables was done by using the Fisher's exact test, the Mann-Whitney test, and the t test. The probability of occurrence in the tests statistics (p) was classified as follows: the difference was considered significant if p is less than .05 or .10, significant tendency if p is between .10 and .20, and not significant if p is more than to .20.

The level of significance on accepting indications for the tests was 5%. However, given the size of the sample and being a novelty study in Brazil, the level of significance of 10% and significant tendency of 20% were considered and showed.

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Comparing the two groups, experimental and control, according to the Fisher's exact test, in relation to age group (p = 1.00), causes of the lowering of consciousness level (p = .46), and days of internment (p = .81), these groups do not differ statistically between themselves; in other words, they can be considered homogeneous. The experimental group had 44.7 years average (18.7 deviation pattern) and 12 days of hospitalization. The control group had 47.7 years average (21.8 deviation pattern) and 22.2 days of hospitalization. As for the causes of the lowering of the consciousness level in general, sedation (11% or 36%) and cranial encephalic trauma (11% or 36%) were the main factors.

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Because the song was selected by a relative and because any song could be chosen, thus the chosen songs were of various types and styles. The age groups, the social levels, and even the ethnic origins of the patients were very different; therefore, these songs related to significant moments in their different lives, personalities, and positive experiences.

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Each of the messages recorded by relatives has displayed in one way or another longing and affection for the patients. In most of them, 27 (90%) of the 30 messages, words such as God, Jesus, and prayer, were frequently used independently of the relatives' religion, and there was a strong expression (Puggina, Silva, & Araújo, 2008).

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Vital Signs

The Mann-Whitney test compared the differences in separate values before and during each stimulus (or silence in the controls) between the control and the experimental groups for the 3 days. Despite the averages of the vital signs in the experimental group being altered most the time in relation to the basal average during both the music and the message, when compared with the control group, there was a statistically significant difference at only some moments (Tables 1 and 2).

Table 1
Table 1
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Table 1
Table 1
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Table 2
Table 2
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Table 2
Table 2
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Comparing the groups, statistically significant alterations were found in the following vital signs: oxygen saturation-Day 1; oxygen saturation-Day 3; and respiratory frequency-Day 3, all occurring during the message. Significant tendencies were as follows: temperature-Day 3 during the message; systolic blood pressure-Day 3 during the music; diastolic blood pressure-Day 3 during the message; and respiratory frequency-Day 2 during both the music and the message.

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Facial Expression

The patients' facial expressions, during each session, were collected in the following way: patients were observed immediately before the intervention, and their basal facial expressions were documented so that these preexisting expressions could be disregarded during the data collection.

Alterations to the patient's baseline expressions were registered (head, mouth movements, eyebrow movements, facial tension and relaxation, tears, unspecific ocular opening, etc.). However, with the great diversity of data, it was not possible to group them; therefore, a simplified analysis was done: if there was presence or absence of alteration in facial expressions during intervention when compared with basal expressions.

The facial alterations registered were only those not previously presented by the patient. The exact number of movements was not considered, but only if there were any new movements in the facial expression. For example, if the patient, before data collection, moved their mouth, as a reflected movement caused by discomfort from the endotracheal tube, this alteration of facial expression was not considered.

When comparing the groups, two statistically significant alterations and two significant tendencies for this variable were found (Table 3). For the variable facial expression, statistically significant alterations were found in Day 1 during the music employment as well as through the message. Significant tendencies were found in Day 2 during the music and the message execution.

Table 3
Table 3
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Analysis by Scales of Statistically Significant Alterations Patients

For a better analysis of the patients with statistically significant alterations and mainly for a better understanding of the influence of the GCS and RSS, the alterations in relation to vital signs and facial expression statistically significant in each of the patients in experimental group were summed together. One or two alterations, at random, were disregarded, and the remainders of these patients were divided into two groups-patients with three alterations and patients with four or five alterations (Table 4)-and described separately.

Table 4
Table 4
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Patients who had three statistically significant alterations also had GCS scores in each of the levels from 3 to 8. As for RSS, only one of the patients was evaluated with this scale, making the analysis more difficult. Patients with four and five statistically significant alterations in the GCS, regarding Days 1 and 3, varied among 5, 7, and 8, such scores that refer to different states of response because of the size of the sample; considering this, we did not feel comfortable with further analyses.

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In our study, the voice message was a stronger stimulus than the music. In another study (Jones, Hux, Morton-Anderson, & Knepper, 1994), the result was similar. During the application of four different auditory stimuli (relatives' voices, classical music, preferable music, and nature sounds), the stimulus of family voices resulted in a larger stimulation of the patient over the other stimuli, and that increase was demonstrated in by physiological measures (pulse and respiratory frequency) as well as by behavioral responses.

The message content was affectionate and meaningful to the patient. A special experience was felt during data collection when direct contact with the patient's relative took place. As the process of how to elaborate their message and music selection was explained to the relative, an insight into the patient's history as a human being became known. The chosen music showed that a special moment in the history of that patient's life meant times of happiness. The wording of the message not only demonstrated affection but also told of the everyday life of the patient. The time spent between the researcher and the relatives was always quite emotional; the relatives remembered various things and special times passed with the patient and many times shed tears of sadness.

The messages have also revealed something very interesting: the attachment to something divine to help overcome the situations, even if that attachment had been weak for a long time. This research, for many relatives, seemed to represent a new opportunity to talk to their loved ones; many were emotionally touched and cried (Puggina et al., 2008).

As found in another study, relatives and patients use religion as a form of feeling safe inside an unknown climate, bringing closer faith and deity, involving someone that they look to for support during these times (Baker & Melby, 1996).

The family members of patients in the ICU feel many things. This is a difficult, painful, and speechless experience. They approach the patient's suffering, break up their daily routines, and feel the constant fear of having a family member die. An approach to these experiences of the relatives, of patients hospitalized in an ICU, can provide the support for health professionals to reflect on their practices, involving welcoming, incorporating relatives as an important focus of healthcare, with a view of surpassing the prevailing biological model. This implies rethinking the relationship established with the family and the work conditions, involving institutional management and policies as well as professional training (Urizzi & Corrêa, 2007).

We found patients with statistically significant alterations in different states of response in the GCS.

When applying auditory stimuli (popular music) in patients in coma state and collecting data considering GCS, electroencephalogram (EEG), and the patients' behavioral response, the researcher (Sisson, 1990) affirms that the level of the coma apparently did not have any relation to the behavioral response.

We also found that the statistically significant alterations were in the variables oxygen saturation, breathing frequency, and facial expression. Some studies (Aldridge, Gustorff, & Hannich, 1990; Sisson, 1990; Walker, Eakes, & Siebelink, 1998) applied different auditory stimuli and evaluated the general response of patients through this procedure.

A researcher that studied music therapy in five coma patients, through a song vocalized by a therapist, evaluated the respiratory frequency, heart frequency, and physical reactions. A variety of reactions were noted: changes in breathing (which became slower and deeper), fine motor movements, opening or closing the hands, head turning, or opening of the eyes for conscience recovery (Aldridge et al., 1990).

Two popular preselected songs were used as stimulus and evaluated through the EEG the effect of the specific sensorial entry in the cortical activity of five patients in state of coma. Two patients showed a response in the EEG and the other three responded by opening the eyes or moving an extremity (Sisson, 1990).

The effects of the intervention through voices of family members were evaluated in 10 patients in the state of coma with brain damage. The physiological parameters (intracranial pressure, blood pressure, pulse, respiratory frequency, medium blood pressure, and oxygen saturation) were observed. No significant statistical differences were found between the average of the measures before, during, or after the message. However, the pulse was a measure that had a bigger change in reference to the other physiological parameters (Walker et al., 1998).

Another study researched the detection integrity of the person's own name in patients with disorders of consciousness. The results suggested that partially preserved semantic processing could be observed in noncommunicative brain-damaged patients, notably for the detection of salient stimuli, such as the subject's own name (Perrin et al., 2006).

Exactly how much these patients are capable of hearing cannot be confirmed, but considering these results, we need to be concerned with what is said in their presence. Studies (Baker & Melby, 1996; Cardim, Costa, Nascimento, & Figueiredo, 2004; Elliott & Wright, 1999) reveal that they have been researching verbal communication with the comatose patient, and they show the problem: The health team, despite recognizing the importance of communication with these patients, still cannot talk to them in a natural way; a few do it, and the ones who do it frequently limit themselves to only informing about healthcare procedures.

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The following variables were evaluated: pulse, temperature, systolic blood pressure, diastolic blood pressure, oxygen saturation, respiratory frequency, and facial expressions. Statistically significant alterations found were in the variables oxygen saturation, breathing frequency, and facial expression.

In this study, the message was a stronger stimulus than the music.

Responses to the auditory stimuli were observed in all of the GCS marks of the patients of the experimental group when statistically significant differences were obtained; therefore, it can be concluded that this variable had little influence to the responses in this study.

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Limits of the Research

Despite the groups being statistically homogeneous, it would be interesting for a future study to work with experimental and control groups together, in other words, for each patient of the experimental group to select one or more controls with common characteristics to the experimental.

Because of the available time, the difficulties found in data collection, and the patients' allocation into two groups (control and experimental), the number of patients made the accomplishment of deeper analyses of the data more difficult.

The nonexistent possibility of a longitudinal study makes some conclusions more difficult; we do not know if the patients who responded more intensely to the incentives remember anything or if they showed improvement of the clinical picture after the research.

It was not possible to evaluate in this study if the song dynamics, harmony, rhythm, or lyrics influenced patients' responses.

The difference between medication regimens of patients, included in this study, could be a limitation of the research. It was not possible to affirm if indeed these medications were similar and did not present some influence on the final results.

The instrument used to measure vital signs had limits. The observation and the data collection of vital signs were performed using hemodynamic monitors to perform this at the same time each patient would have had to have their own individual monitor; therefore, the data collection did not occur at the same time in relation to vital signs.

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Final Considerations

With regard to the response capabilities of patients with disorders of consciousness, there are many questions to be asked and many of them still remain unanswered. This theme is a concept rarely studied in Brazil, and most definitely more research is necessary. Health professionals must remain conscious of the fact that research has clearly indicated that a certain amount of perception by these patients does in fact exist and thoughtless or inadequate comments should never be spoken in their presence; at the same time, taking precautions to always be ethical by their bedside is of utmost importance and the overall purpose of this study.

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