A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery on Patient Satisfaction
Phase: NA
Conditions: Patient Satisfaction
Sponsor: Tufts Medical Center

PROTOCOL TITLE: A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery 
on Patient Satisfaction  
VERSION DATE: Oct 16, 2017 
 
Page 1 of 14 
 
 
STUDY TITLE: 
 
A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery on Patient Satisfaction  
 
 
STUDY SPONSOR: 
 
Department of Anesthesiology and Perioperative Medicine, Tufts Medical Center 
 
PRINCIPAL INVESTIGATOR  
 
Dan Drzymalski, MD 
Assistant Professor 
Tufts University School of Medicine 
Department of Anesthesiology and Perioperative Medicine 
Tufts Medical Center 
Phone: 617-913-8168 
Email: ddrzymalski@tuftsmedicalcenter.org 
 
 
CO-INVESTIGATORS 
 
Mohammad Dahlawi, MD 
Post Doctoral Research Fellow 
Tufts University School of Medicine 
Department of Anesthesiology and Perioperative Medicine 
Tufts Medical Center 
Phone: 202-285-6420 
Email: mdahlawi@tuftsmedicalcenter.org 
 
 
       
 
 
 
 
 
 
 
 
Tufts Health Sciences IRB 
Protocol Template 
Template Revised: 08/16/2016 
 
 
 
 
 

PROTOCOL TITLE: A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery 
on Patient Satisfaction  
VERSION DATE: Oct 16, 2017 
 
Page 2 of 14 
 
 
Table of Contents  
 
1. 
Study Schema 
4 
2. 
Introduction 
5 
2.1. 
Background and Rationale 
5 
2.2. 
Risks to Subjects 
5 
2.3. 
Potential Benefits to Subjects 
5 
2.4. 
Alternatives 
6 
The alternative is not participating in the study. 
6 
3. 
Objectives 
6 
4. 
Enrollment and Withdrawal 
6 
4.1. 
Inclusion Criteria 
6 
4.2. 
Exclusion Criteria 
6 
4.3. 
Withdrawal of Subjects 
6 
4.4. 
Recruitment and Retention 
6 
4.4.1. 
Local Recruitment Methods 
6 
4.4.2. 
Study-Wide Recruitment Methods 
6 
 
6 
4.4.3. 
Payment 
7 
4.4.4. 
Reimbursement 
7 
5. 
Study Design 
7 
5.1. 
Study Timelines 
7 
5.2. 
Procedures 
7 
5.3. 
Evaluations 
7 
5.4. 
Collection and Storage of Human Biological Specimens (Tissue Banking) 
7 
6. 
Ethics and Protection of Human Subjects 
8 
6.1. 
Informed Consent Process 
8 
6.2. 
Waiver or Alteration of Consent Process 
8 
6.3. 
Confidentiality 
8 
6.4. 
Provisions to Protect the Privacy Interests of Subjects 
8 
6.5. 
Provisions to Monitor the Study to Ensure the Safety of Subjects 
8 
6.6. 
Compensation for Research-Related Injury 
9 
6.7. 
Economic Burden to Subjects 
9 
 
6.10 Vulnerable Populations 
9 
7. 
Adverse Event Monitoring 
10 
7.1. 
Definitions 
10 
7.2. 
Reporting Procedures 
10 

PROTOCOL TITLE: A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery 
on Patient Satisfaction  
VERSION DATE: Oct 16, 2017 
 
Page 3 of 14 
 
8. 
Statistical Considerations 
10 
8.1. 
Study Endpoints 
10 
8.2. 
Statistical Analysis 
10 
8.3. 
Number of Subjects 
10 
8.4. 
Data Management 
10 
8.5. 
Randomization 
10 
9. 
Drugs or Devices 
11 
10. 
Study Administration 
11 
10.1. 
Setting 
11 
10.2. 
Registration 
11 
 
11 
10.3. 
Resources Available 
11 
10.4. 
IRB Review 
11 
10.5. 
Multi-Site Research 
11 
10.6. 
Community-Based Participatory Research 
11 
10.7. 
Sharing Results with Subjects 
12 
References 
12 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

PROTOCOL TITLE: A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery 
on Patient Satisfaction  
VERSION DATE: Oct 16, 2017 
 
Page 4 of 14 
 
 
1. Study Schema 
 
 
 
Prior to 
Enrollment
• Total N, obtain informed consent if no 
contraindication to epidural analgesia
Randomize
• Arm 1: Control (no music)
• Arm 2: Intervention - Mozart Sonata Music
At the Time of 
the Procedure
• Evaluate the effect of music on patient vital 
signs
Post-Procedure
• Evaluate the effect of music on patient 
satisfaction

PROTOCOL TITLE: A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery 
on Patient Satisfaction  
VERSION DATE: Oct 16, 2017 
 
Page 5 of 14 
 
2. Introduction 
 
2.1. 
Background and Rationale 
 
Several studies have demonstrated that music can improve various outcomes during labor and delivery. 
However, many of these studies suffer from severe methodological flaws. In particular, patient 
satisfaction is often measured on a simple VAS scale, where 0 is no satisfaction and 10 is the highest 
satisfaction. However, patient satisfaction is a complex parameter to measure, and may be affected by a 
number of different factors. This will be the first study performed on the labor and delivery unit to assess 
patient satisfaction with a validated, reliable, 22-question survey developed by Morgan et al. (Morgan 
1999), in the setting of music or no music during the cesarean delivery.  
 
Although “music” is an all-encompassing term that describes sound with different pitches and rhythms 
that comes together as a harmonious whole, not all music is the same. Using “music” for therapeutic 
purposes would be the equivalent of using “antibiotics” to cure an infection; it is too general of a term, 
and unlikely that such a general use of music would show a valid therapeutic benefit. However, Conrad et 
al. demonstrated that specific selections of Mozart piano sonatas, which have a specific rhythm and mode, 
improve patient anxiety through a biochemical mechanism (changing the plasma levels of IL-6 and 
epinephrine). Therefore, in this study, when we refer to “music,” we will specifically plan on using the 
same Mozart sonatas as described in Conrad’s prior studies.  
 
 
2.2. 
Risks to Subjects 
 
Participation in this study will include a risk that if the music is too loud, injury to the tympanic 
membrane may occur. This complication will be avoided with the patient’s active participation at all 
times to report if the music is too loud, and volume will be adjusted according to the patient’s preference.    
 
Psychosocial (non-medical) risks include the concern for coercion to participate. To minimize this risk, 
the co-investigator of the study, who is an anesthesia research fellow, will recruit all participants greater 
than or equal to one hour prior to participation in the study.    
 
Other risks may include the unintentional loss of patient confidentiality. In order to minimize that risk, all 
paperwork will be stored in a secure location. Furthermore, all electronic data will be held in a Tufts 
Medical Center provided, password protected, encrypted, Box storage account. 
 
2.3. 
Potential Benefits to Subjects 
 
There is no direct benefit for participation in the study.  
 
Subjects being randomized to the intervention arm, Mozart music, may receive  greater overall 
satisfaction with their delivery experience. 
 
2.4. 
Alternatives 
 
The alternative is not participating in the study.  
 
 

PROTOCOL TITLE: A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery 
on Patient Satisfaction  
VERSION DATE: Oct 16, 2017 
 
Page 6 of 14 
 
3. 
Objectives 
 
The objective of this study is to determine the effect of music on patient satisfaction and anxiety during 
cesarean delivery. We will evaluate this objective by studying the following outcomes: 
• 
The primary outcome of this study is patient satisfaction. This outcome will be measured using 
Morgan’s “Maternal Satisfaction Scale for Cesarean Section” (MSSCS) on post-operative day 
one during the hours of 8am-1pm.  
• 
The secondary outcome will include anxiety at several time points (immediately prior to and after 
neuraxial technique placement as well as at the end of surgery). This will be evaluated using a 
simple numeric rating score from 0-10, where 0 is no anxiety and 10 is the greatest anxiety.  
 
We hypothesize that parturients exposed to music during cesarean delivery will have greater overall 
satisfaction and less anxiety. 
 
4. 
Enrollment and Withdrawal  
4.1. 
Inclusion Criteria 
• 
Age: 18-50 years old 
• 
Scheduled for elective cesarean delivery 
• 
Nulliparity 
• 
Singleton pregnancy 
• 
Planning cesarean delivery 
• 
Full term fetus (≥37.0 weeks gestational age) 
• 
Healthy fetus (no known congenital diseases at the time of surgery) 
• 
Requesting neuraxial anesthesia for the procedure 
• 
Able to provide informed consent 
• 
Spontaneous labor 
 
4.2. 
Exclusion Criteria 
• 
Patient refusal 
• 
Prior history of extensive abdominal surgery 
• 
Active labor 
• 
Contraindication to neuraxial anesthesia 
• 
Uncorrected coagulopathy 
• 
Infection at the skin site of epidural placement 
• 
Increased intracranial pressure 
• 
Untreated hemodynamic instability 
• 
Known hypersensitivity to local anesthetics (a.k.a. amide or ester allergy) 
• 
Patients with impaired hearing 
• 
Patient on anti-anxiolytic medication 
 
4.3. 
Withdrawal of Subjects 
 
● Withdrawal of study subjects without their consent may occur in parturients who consent to the study 
but do not undergo neuraxial placement. 
● Patients who decide to withdraw prematurely will be withdrawn and provided the standard of care at 
Tufts Medical Center. 
 

PROTOCOL TITLE: A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery 
on Patient Satisfaction  
VERSION DATE: Oct 16, 2017 
 
Page 7 of 14 
 
4.4. 
Recruitment and Retention 
4.4.1. 
Local Recruitment Methods 
Faculty in the Obstetrics and Gynecology Department at Tufts Medical Center will be informed about 
the study at one of the departmental meetings. They will be asked to inform their patients about this 
study in their clinic visits. The co-investigator, Dr. Dahlawi will review medical records and 
schedule of medical procedures to know their time and date. Once the patients arrive to the labor 
and delivery unit, he will meet with the patients and discuss the study with them further. If they agree to 
participate, informed consent will be obtained. 
4.4.2. 
Study-Wide Recruitment Methods 
Is this is a multicenter study where subjects will be recruited by methods not under the control of the 
local Tufts site (e.g., call centers, national advertisements)?  
 
4.4.3. 
Payment  
Will subjects receive money, gifts, or any other incentive for participating in this study?  
This does not include reimbursement for expenses, which is considered in the next section.                    
     
4.4.4. 
Reimbursement   
Will subjects be reimbursed for their expenses, such as travel, parking, meals, or any other study related 
costs? 
   
                                  
5. 
Study Design 
5.1. 
Study Timelines 
● Participation begins at the time of consultation for cesarean delivery on the day of surgery, where the 
co-investigator Dr. Dahlawi will approach the participants and ask them to sign the ICF, and it ends 
after the post-anesthesia check on postoperative day 1. After recruitment and consent, patients will be 
randomized using a computer-generated randomization scheme will be used to allocate patients to one 
of the arms of the study.  
● The two arms of the study are as follows:  
o 
Control group: baseline hemodynamics and anxiety screen; no music 
o 
Intervention group – Mozart: A study investigator will turn on a playlist of pre-selected 
Mozart music. 
● Given our sample size calculation and that not all women who are approached will consent to the 
study, we expect recruitment to take 12 months. 
● The estimated date for primary analyses will be November 2018 
● We estimate that it will take an additional 12 months to complete the study, including statistical 
analysis and manuscript preparation. 
 
5.2. 
Procedures 
● Is there a placebo control arm?  
 
After reviewing their medical records, the co-investigator, Dr. Dahlawi, will approach parturients meeting 
inclusion criteria on the day of admission for scheduled cesarean delivery at Tufts Medical Center. The 

PROTOCOL TITLE: A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery 
on Patient Satisfaction  
VERSION DATE: Oct 16, 2017 
 
Page 8 of 14 
 
research study will be explained and parturients will be given an informed consent form to read. After the 
parturient read through the informed consent form, think about the risks and benefits, and ask questions, 
she will be asked to sign the form if she wishes to participate in the study. The informed consent form 
will then be stored in the principal investigator’s locked office. Once a study subject is enrolled, the 
anesthesia provider, obstetric provider, as well as the nurse will be informed that this parturient is part of 
the study.  
 
Once the subject is recruited, patient demographic data and baseline vitals signs (including anxiety levels) 
will be collected. All parturients will receive a standardized spinal technique using 1.6 mL of 0.75% 
hyperbaric bupivacaine with 15mcg fentanyl and 200mcg morphine, which is the typical standard dose at 
Tufts Medical Center in nulliparous parturients.  
 
Upon entry into the operating room, parturients who are randomized to music will start to listen to the 
Mozart piano sonatas during the entire procedure, while those randomized to no music will not listen to 
any music. After at least 5 minutes of listening to music and immediately after the spinal anesthetic is 
placed, anxiety levels and vitals signs will be assessed again. At the end of surgery, after coming into the 
PACU, anxiety and vitals will be assessed. Finally, on postoperative day 1, during the hours of 8AM – 
1PM, patient satisfaction will be assessed by administering the MSSCS, which should take about 10 
minutes to complete. After that, her participation in the study will end. 
 
5.3. 
Evaluations 
Will you perform any laboratory tests for this study?  
 
5.4. 
Collection and Storage of Human Biological Specimens (Tissue Banking) 
Will biological specimens be stored for future, unspecified, research?   
 
 
6. 
Ethics and Protection of Human Subjects 
6.1. 
Informed Consent Process 
Will subjects be required to provide informed consent? 
  
● The parturients will be informed about the study during a clinic visit before being admitted for 
surgery.  
● The informed consent will be taken in a private room in the labor and delivery unit on the day of the 
procedure.  
● The patient will have one hour before the start of the procedure to make a decision regarding 
enrollment. 
● The consent will be obtained in person and documented in writing following “SOP: Informed 
Consent Process for Research (HRP-090)”. 
● Non-English speakers will be enrolled using interpreters and IRB approved Short Forms per the 
IRB’s Short Form policy 
 
 
 

PROTOCOL TITLE: A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery 
on Patient Satisfaction  
VERSION DATE: Oct 16, 2017 
 
Page 9 of 14 
 
6.2. 
Waiver or Alteration of Consent Process 
 
● Is a waiver or alteration of the consent process being requested for this study?  
 
● Is a waiver of the consent process being requested for parents for research involving children?  
 
 
● Is a waiver of the consent process for planned emergency research being requested?  
 
 
6.3. 
Confidentiality 
 
In order to maintain confidentiality, the following measures will be taken: 
● All study related materials, including consent forms and data collection forms, will be stored in 
the principal investigator’s locked office 
● The principal investigator and co-investigators will have exclusive access to the forms 
● Digital data will be stored in a hospital provided, password protected, Box account 
● Data will not be coded, as it will be stored in a protected online account.  
● Records will be stored for 7 years after the study is closed with the IRB, as per IRB policy. 
● A certificate of confidentiality will not be obtained. 
 
6.4. 
Provisions to Protect the Privacy Interests of Subjects 
 
Subjects will be assured that their interaction with any member of the research team is optional, as well as 
the information they share. 
 
6.5. 
Provisions to Monitor the Study to Ensure the Safety of Subjects 
 
● The standard of care at Tufts Medical Center is to collect safety information on all patients 
undergoing surgery through an established computerized system called Anesthesia Touch. Safety 
information and adverse events that will be collected includes failure of spinal analgesia. For the 
purposes of this study, the principal investigator will periodically (every 6 months) evaluate the safety 
data and assess the risks and benefits to assess subject safety. The purpose of obtaining this 
information is to ensure that no untoward events are occurring. This information will be obtained 
after signing the ICF. The statistical tests that will be performed on the safety data to determine 
whether harm is occurring will include a chi-squared test, to compare proportions between groups. 
● Stopping rule: we do not anticipate a stopping rule to this study. 
● No Data and Safety Monitoring Board will be used in this study.  
 
6.6. 
Compensation for Research-Related Injury 
Does the research involve greater than minimal risk to subjects? 
 
6.7. 
Economic Burden to Subjects 
Does the research involve any costs to subjects? 

PROTOCOL TITLE: A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery 
on Patient Satisfaction  
VERSION DATE: Oct 16, 2017 
 
Page 10 of 14 
 
 
 
6.8.      Vulnerable Populations 
            Will pregnant women be enrolled?   
 
● The procedure in the study is not a part of the standard care at Tufts Medical Center for parturients. 
However, it is not uncommon for music to be played in the operating room during cesarean delivery, 
at the patient’s request. 
● This study’s risk to the fetus is NOT greater than Minimal Risk. 
● No inducements, monetary or otherwise, will be offered to terminate a pregnancy and that in the case 
of a fetus; the fetus is not the subject of a planned abortion. 
● Research team will have no part in any decisions as to the timing, method, or procedures used to 
terminate a pregnancy or in determining the viability of a neonate. 
 
Will the research involve neonates of uncertain viability or non-viable neonates?  
 
 
Will subjects who are not yet adults (neonates, children, teenagers) be enrolled?  
 
 
      Will minors who are:  
i) 
married, widowed, divorced; or  
ii) 
the parent of a child; or  
iii) 
a member of any of the armed forces; or  
iv) 
pregnant or believes herself to be pregnant; or  
v) 
living separate and apart from his/her parent or legal guardian, and is managing his/her own 
financial affairs  
      be approached for study participation for either themselves or their child?  
      
 
 
      Will wards of the state and/or children at risk of becoming wards of the state be enrolled (this includes 
foster children or any child that is in state custody)?            
      
 
 
Will cognitively impaired adults (adults with impaired-decision making capacity) or adults who may lose 
the capacity to consent be enrolled?  
 
 
Will prisoners be enrolled?  
 
Will students and/or employees be enrolled in this research?  
 

PROTOCOL TITLE: A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery 
on Patient Satisfaction  
VERSION DATE: Oct 16, 2017 
 
Page 11 of 14 
 
 
 
 
7. 
Adverse Event Monitoring 
7.1. 
Definitions 
 
The study does not carry a higher risk of adverse events than typically expected. Also, there is a risk of injury 
to the tympanic membrane if the music is too loud. The risks to the infant, which will initially be intra-uterine 
during the study and eventually delivered by the end of the study will be minimal.  
 
Unanticipated problems: any incident, experience, or outcome that meets all of the following criteria: 
unexpected; related or possibly related to participation in the research; and suggests that the research places 
subjects at a greater risk of harm than was previously known or recognized.  
 
7.2. 
Reporting Procedures 
 
The co-investigator, Dr. Dahlawi, will be responsible for contacting the principal investigator to report the 
occurrence of adverse events. The principal investigator will then complete any necessary safety forms, 
include the Anesthesia Department’s Quality Assurance form. Reportable new information will be reported to 
the IRB per the Tufts Health Sciences IRB’s Reportable New Information policy within 5 business days of an 
event. 
 
 
8. 
Statistical Considerations 
8.1. 
Study Endpoints 
● Primary endpoint: measurement of patient satisfaction  
● Secondary endpoint: measurement of patient anxiety levels, hemodynamics, and postpartum 
analgesics requirement. 
8.2. 
Statistical Analysis 
● Given that our primary outcome is the satisfaction between two groups, we will use a statistical test to 
compare proportions (the Chi-squared test).  
● Given that our secondary outcomes include mean patient anxiety levels and mean blood pressure, we 
will use a statistical to compare means (Student’s t-test).  
8.3. 
Number of Subjects 
● A previous study demonstrated that the total satisfaction score in parturients who get midazolam pre-
operatively vs. those who do not is 130.3 ± 10.5 vs. 113.6 ± 11.9, respectively. Although we do not 
have similar data for music, we expect that the effect of Mozart music will be similar to that of 
midazolam because both music and midazolam work as anxiolytics and may play an important role in 
patient satisfaction. Therefore, we will expect to see a similar difference in patient satisfaction.  
● Using G*Power 3.1, we determined that in order to detect a difference between the two groups using 
a two-tailed T-test with power of 80% and alpha of 0.05, the total number of subjects needed is 18. In 
order to account for 20% attrition rate, the total number of subjects that would be required to 
complete study aims is 22.  

PROTOCOL TITLE: A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery 
on Patient Satisfaction  
VERSION DATE: Oct 16, 2017 
 
Page 12 of 14 
 
8.4. 
Data Management 
● Data collection forms and an excel spreadsheet with all of the analyzed data will be stored during the 
study period in the PI’s private locked office and hospital approved Box account, where access is 
exclusive to the research team.  
● Name, date of birth and medical record number, vital signs and dates of service will be 
collected. Data sheets used in the collection of PHI and generation of the database will be 
destroyed after generation of the database. 
 
8.5. 
Randomization 
Will subjects be randomized?  
 
In order to randomly allocate study subjects to one of three arms entirely by chance, we will use the on-
line randomization tool “Research Randomizer Version 4.0, www.randomizer.org,” which is a computer-
based "random number generators," the numbers are generated by use of a complex algorithm (seeded by 
the computer's clock) that gives the appearance of randomness. This tool has been studied and validated 
as an adequate randomization tool, to generate a randomization list. Allocation concealment will be 
maintained by preparing sequentially numbered, sealed, opaque envelopes, which will contain the 
randomization assignment consistent with the generated randomization list. The study is not blinded. 
 
9. 
Drugs or Devices 
Will the research involve drugs?   
  
Will the research involve devices?   
 
10. 
Study Administration 
10.1. 
Setting 
Tufts Medical Center will be the sole research site. 
 
10.2. 
Registration 
The co-investigator, Dr. Dahlawi, will ensure the eligibility of subjects and obtain their consent before 
receiving any study related interventions.  
 
10.3. 
Resources Available 
The research team is composed of the following members: 
● Principal Investigator: Dan Drzymalski, MD Assistant professor of Anesthesiology. Primary 
investigator responsible for the preparation, design, conduct, and administration of the study.  
● Co-investigator: Mohammad Dahlawi, MD Research fellow. Responsible for writing the study’s 
protocol under the PI guidance, obtaining the informed consent, managing data collection and coding 
and coordinating various sectors in the study. 
● Tufts Medical Center facilities provide medical resources that might be needed by study subjects. 
 

PROTOCOL TITLE: A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery 
on Patient Satisfaction  
VERSION DATE: Oct 16, 2017 
 
Page 13 of 14 
 
10.4. 
IRB Review 
● An appropriate IRB registered with the OHRP, will review and approve this study.  
● Any amendments to the protocol or informed consent documents will be reviewed and approved by 
the IRB prior to use, unless required to eliminate an apparent immediate hazard to subjects. 
10.5. 
Multi-Site Research 
Is this a multi-site study where Tufts is the sponsor, primary grant recipient, or coordinating site?: 
 
 
10.6. 
Community-Based Participatory Research 
Will this study involve community-based participatory research?  
 
10.7. 
Sharing Results with Subjects  
Will results (overall study results or individual subject results, such as results of investigational diagnostic 
tests, genetic tests, or incidental findings) be shared with subjects or others (e.g., the subject’s primary 
care physician or the subject’s treating physician)?   
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

PROTOCOL TITLE: A Randomized Controlled Trial of Music vs. No Music During Cesarean Delivery 
on Patient Satisfaction  
VERSION DATE: Oct 16, 2017 
 
Page 14 of 14 
 
 
 
 
 
 
 
References 
 
• 
Morgan PJ, Halpern S, Lo J. The development of a maternal satisfaction scale for caesarean section. Int J 
Obstet Anesth 1999;8:165-70. 
• 
Drzymalski, DM, Tsen, L, Palanisamy, A, Zhou, J, Huang, CC, Kodali, B. “A Randomized Controlled 
Trial of Music Use during Epidural Catheter Placement on Laboring Parturient Anxiety, Pain and 
Satisfaction.” Anesth Analg. 2017 Feb;124(2):542-547. 
• 
Koch ME, Kain ZN, Ayoub C, Rosenbaum SH. The sedative and analgesic sparing effect of music. 
Anesthesiology 1998;89:300-6. 
• 
Barnett SF, Alagar RK, Grocott MP, Giannaris S, Dick JR, Moonesinghe SR. Patient-satisfaction 
measures in anesthesia: qualitative systematic review. Anesthesiology 2013;119:452-78. 
• 
Conrad C, Niess H, Jauch KW, Bruns CJ, Hartl W, Welker L. Overture for growth hormone: requiem for 
interleukin-6? Crit Care Med 2007;35:2709-13.