a Institute of Health and Caring Sciences. Sahlgrenska Academy, University of Gothenburg, Swedenb Occupational and Environmental Medicine, Sahlgrenska Academy, University of Gothenburg, Swedenc Woodruff School of Mechanical Engineering, Georgia Institute of Technology, USAd Borås University College, School of Health Sciences, Sweden
Accepted 28 March 2012
KEYWORDSSound;Environment;ICU delirium;Intensive care unit
Summary This study had two aims: first to describe, using both descriptive statistics andquantitative content analysis, the noise environment in an ICU patient room over one day,a patient’s physical status during the same day and early signs of ICU delirium; second, todescribe, using qualitative content analysis, patients’ recall of the noise environment in theICU patient room. The final study group comprised 13 patients. General patient health statusdata, ICU delirium observations and sound-level data were collected for each patient over a 24-hour period. Finally, interviews were conducted following discharge from the ICU. The soundlevels in the patient room were higher than desirable and the LAF max levels exceed 55 dB70—90% of the time. Most patients remembered some sounds from their stay in the ICU andwhilst many were aware of the sounds they were not disturbing to them. However, some also
∗ Corresponding author at: Institute of Health and Caring Sciences, University of Gothenburg, Arvid WallgrensBacke, Box 457, SE-405 30Sweden. Tel.: +46 31 786 6108; fax: +46 31 786 6110.
Implications for clinical practiceThis study illustrates the need to improve the physical environment in the ICU patient room.It also indicates that intervention strategies are needed that include:
• Acoustical improvements• Reduction of noise• Reducing the volumes of technical alarms
On-going research seeks to describe and understand the existing conditions of the ICU patient room and find connectionsbetween noise and health. However, until the phenomenon is better understood nurses in ICU must work with the toolsavailable. It is vital for the nurses caring for persons in ICU to have proficient knowledge of the patients’ experiencesof sounds and noises.
ntroduction
he high level of noise in hospital intensive care unitsICUs) is a well-documented reality and previous studiesave shown mean levels of between 55—66 dB LAeq (equiva-ent continuous level) during the daytime in patients’ rooms,ith maximum levels reaching 80 dB LAFmax (maximum
evel with time weighting FAST) (Akansel and Kaymakci,008; Bailey and Timmons, 2005; Christensen, 2007; Ryherdt al., 2008; Tsiou et al., 1998). This far exceeds theecommendations in the World Health Organisation (WHO)‘guidelines for community noise’’, stating that for goodleep, the sound level should not exceed 30 dB (LAeq) bothor continuous background noise and individual noise (WHO,999). The highest noise levels in the ICU are related tohe staff conversation, continuous treatment and the usef advanced technical equipment (Akansel and Kaymakci,008; Xie et al., 2009).
Noise as a concept is often defined as any sound that isnwanted, undesirable or without musical quality (Hilton,985). This means that sound and noise are complex phe-omena and how they are experienced depends on theound level, the nature of the sound and the subjectivexperience which is influenced by a number of aspectsuch as cultural and social factors, individual personal-ty and attitudes (Belojevic et al., 2003). Unfortunately,ost research has focussed on sound levels and few stud-
es describe the patients’ own experience of noise andounds in the ICU. There are some examples of studieshere patients have mentioned the sound environment. Inne qualitative study, some patients described the environ-ent as chaotic, with a lot of noise, beeps and rattling
ounds (Lof et al., 2006) and in a questionnaire studyhe patients themselves scored noise from other patientsn the same room as the most disturbing (Akansel andaymakci, 2008). Additionally, in another qualitative studyatients reported that the noise made it impossible forhem to sleep (Granberg et al., 1998). It is unclear to whategree the sounds and noises influence the ICU patient. Wenow from other areas that hospital noise influences themmune, the cardiovascular and the endocrine systems neg-tively (Christensen, 2002; Hagerman et al., 2005; Ising and
in ICUs suffer from physical and psychological disorders insome way. Unfortunately these effects are poorly investi-gated.
One of these distressing patient disorders that maybe related to the sound environment is the high rate ofintensive care delirium (ICU delirium) amongst patients inICUs (Van Rompaey et al., 2008). ICU delirium denotesa state of acute confusion and change in cognition or aperceptual disturbance that develops over a short period(hours to days) and fluctuates over time (Granberg et al.,1996; Delirium and Cognitive Impairment Study Group, 2010(www.icudelirium.org)). Two different states of deliriumhave been identified, hyperactive delirium, characterisedby agitation, restlessness and emotional instability andhypoactive delirium, characterised by apathy and lack ofresponsiveness (Girard et al., 2008; Granberg-Axell et al.,2001; Liptzin and Levkoff, 1992). Patients have reportedthat noise or a sudden loud sound triggered the devel-opment of so-called unreal experiences (Granberg et al.,1999). ICU delirium is a severe condition that must betaken seriously since various studies have shown that it isa predictor of higher mortality and a longer ICU stay (Elyet al., 2001a, 2004; Girard et al., 2008; Thomason et al.,2005). Many physical risk factors have been identified butthe main cause of ICU delirium remains unknown (Ouimetet al., 2007). The unique sound environment with high levelsthat fluctuate over time, potentially affecting the patient’sbiorhythm, might be a precipitating factor, but knowledgeis limited and more research is needed. In summary, it isobvious that the patients’ perceptions of sound in ICUs arenot just a matter of sound levels but also depend on thesonic characteristics and individual circumstances at theparticular moment. It is therefore of great importance toelucidate the phenomenon of sound as a whole, including thepatient’s own experiences together with measured soundlevels. Moreover, there is a lack of knowledge regardingthe negative effects of the high sound level and disturb-ing noises in the ICU, particularly when it comes to ICUdelirium.
This study had two aims: first to describe, using a quanti-tative approach, the noise environment in an ICU patientroom during one day, a patient’s physical status during
raun, 2000). We also know that the sounds and disturb-ng noise in ICUs affect the sleep cycle in a negative wayHonkus, 2003). It is therefore also probable that patients
tdt
he same day and early signs of ICU delirium; second, toescribe, using a qualitative approach, patients’ recall ofhe noise environment in an ICU patient room.
Observa�ons curvesand pa�ent recor ds24 ho urs13 pa� ents
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Figure 1
Method
Participants and settings
This study is to be seen as a pre-study for the planning anddesign of a larger study where the aim is to investigatethe relationship between sound (objective and subjective)and the occurrence of ICU delirium and/or other factorsof interest. The present study was carried out in a gen-eral medical—surgical ICU in a county/regional hospitallocated in South-Western Sweden, which treats adults andsometimes children but not infants. Between 700 and 800patients are admitted annually and the unit is the only ICUin the hospital. The mean acute physiology and chronichealth evaluation II (APACHE II) (Knaus et al., 1985) score forthe unit is 17.0 (2009). The unit was built to accommodate13 beds and was often filled to capacity but at the timeof the study treatment was limited to eight patient beds.This means that the study setting should be considereda high-tech environment with a heavy workload puttingpressure on the professionals working there. The patientrooms were shared rooms for two or three patients. Thenursing staff consisted of 70 registered nurses (RNs) with aone-year special education in intensive care and 30 enrollednurses (ENs). One RN and one EN normally work together,where the former is responsible for the planning, deliveryand evaluation of the nursing care. Generally two patientsare allocated to each pair. The ICU has one chief physicianand two other anaesthetists responsible for the intensivecare treatment. In addition there are junior physiciansworking emergency duty hours.
Nineteen patients were recruited using convenience sam-pling. Exclusion criteria were head injury, known hearingimpairment and dementia. Patients for whom surgery wasplanned were invited in advance to participate in the studyby a ward nurse during a planned pre-operative assessmentvisit. In cases of acute admission to the ICU, the patientswere recruited by their allocated ICU nurse. In cases wherethe patient was unable to communicate, the allocated ICUnurse asked the patients’ next of kin for vicarious informedconsent. The patient was then asked for his/her personalinformed consent after the acute phase when he/she wasno longer influenced by drugs or the medical condition. Data
were destroyed if the patient declined to participate ordied.
The Regional University Ethics Research Committeeapproved the study.
dy plan.
ata collection
ultiple categories of data were simultaneously collectedor each patient over a 24-hour period: (1) general patientealth status data, (2) notes of signs of possible ICU deliriumobservations) and (3) sound level data. All three categoriesf data were quantitative as described in the Aims sectionf this paper. This 24-hour period was chosen because bothay and night sound was of interest and the particular dayhosen was judged to be an ‘‘ordinary ICU day’’. Finally,4) qualitative interviews were conducted with the patientsollowing discharge from the ICU. See Fig. 1.
1) General patient health statusData were collected from protocols describing nurs-
ing treatment and observations together with medicaldocumentation comprising data concerning the fulfil-ment of the patient’s physiological needs (e.g. bloodpressure, breathing and heart rate, regimen for seda-tion and ventilation, etc.). In addition, data concerningthe patient’s ordinary physiologically monitored mea-surements and medications were printed and collectedfor further analysis.
2) ICU delirium observationsStructural observations were made every hour using
a protocol for registrations of early signs of the devel-opment of ICU delirium. The protocol, developed byGranberg-Axell et al. (2001), is based on observations ofICU patients in connection with and following extuba-tion/decanulation, according to the Statistical Manualof Mental Disorders Criteria (DSM-IV). The protocol hasnot yet been analysed regarding validity or reliabil-ity since is not an assessment tool for diagnosing ICUdelirium but is designed as an aid to help nurses tobe aware of and register early signs of ICU delirium.The protocol was chosen as the purpose was to reg-ister changes of behaviour every hour without wakingthe patient. This time period was chosen as it is knownthat delirium can fluctuate over time (Granberg et al.,1999). The registrations concerned the patient’s motoractivity, mimicry, wakefulness/contact and whether thepatient was calm or anxious and was able to communi-cate. The observations were carried out by an EN or theRN who was allocated to the patient and were made
continuously over 24 hours (both as frequency and/oras an on-going occurrence). Demographic data such asgender, age, current pharmacological treatment, causeof treatment and length of ICU stay were registered.
272 L. Johansson et al.
Table 1 Subject demographics.
Patient nr. Sex Age Diagnosis ICU lengths of stay (days)
1 M 63 Pneumonia 52 M 63 Sepsis 93 F 81 Thrombosis 34 M 57 Pneumonia 35 M 57 Aortic aneurysm 16 F 60 Pain treatment 17 M 67 Aortic aneurysm 18 F 86 Rectal cancer surgery 19 M 77 Pulmonary embolism 1
10 F 51 Guillain—Barré 3311 M 77 Aortic aneurysm 412 F 63 Whipples surgery 1
Pa
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tsamSaC
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R
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13 F 60
3) Sound level dataParallel with the registrations and collection of proto-
cols, measurements of dB(A)sound pressure levels witha one-minute average interval were carried out using aBruel & Kjaer 2260 sound level meter. The data wereanalysed using B & K Evaluator software and the A-weighted equivalent levels sampled during 24 hours(LAeq24h) and A-weighted maximum levels (LAFmax)are given in this paper. The ‘‘A’’ implies that a fre-quency filter, ‘‘A-weighting network’’, was used. Thisfilter reduces the contribution of low frequency soundenergy, increasing its similar to the response of thehuman ear (Speaks, 1999). The recording device wasclose to the patient’s beds and took place over the same24-hour periods as the patient’s physical status data col-lection and ICU delirium observation.
4) Qualitative follow-up interviewsThe final part of the data collection process was a
tape-recorded unstructured interview held after thepatient had moved out of the ICU. The interviews werecarried out at a time and place that the patients them-selves determined. The open-ended interview questionsfocussed on memories of sounds and of the ICU environ-ment in general (Fig. 1).
ata analysis
ontent analysis is an established method used in the analy-is of textual material and aims to provide new insights andlarify and describe an actual target as broadly as possibleKrippendorff, 2004). It can be used as both a qualitative and
quantitative method. Qualitative content analysis focussesn the subjective interpretation of the content of the textHsieh and Shannon, 2005) and is a systematic process ofoding and identifying themes or patterns, whilst the pur-ose of quantitative content analysis is to code text datand describe the findings by means of statistics.
In this study data were subjected to both qualitative and
uantitative content analysis. Descriptive analyses of demo-raphic variables (age, length of stay (LOS)) are presented.ecause of the small sample data are presented descrip-ively using non-parametric statistics (medians) except for
ttapm
ncreatitis 65
he sound levels which were analysed using parametrictatistics (means). Level of significance was set to 0.05. Tonalyse possible relationships between sound levels (LAF-ax and LAeq) and number of early signs of ICU delirium, the
pearman correlation test was used. The Statistical Pack-ge for the Social Sciences for Windows 18.00 (SPSS Inc.,hicago, IL, USA) was used for all analyses.
The interviews were analysed using qualitative conven-ional manifest content analysis (Hsieh and Shannon, 2005)nd followed the process of organising and integrating textsnto emerging codes, subcategories and categories. First,he whole interview text was read through several timespen-mindedly and considered before an overall view of theext was reached. From this careful reading, key words oroncepts were identified and organised as codes, that is,ords and phrases related to the purpose of the study. Theodes were then sorted into subcategories and categories,ccording to differences and similarities. Finally definitionsor each category were developed.
esults
ll data were collected between May 2007 and July 2008. Ofhe 19 patients who participated in the study, three died inhe ICU, one refused to participate further and two could note contacted for an interview. The sound measurements ofne patient are missing (pat nr 1) due to technical problems.he final study group consisted of 13 patients, six women andeven men, with a median age of 63 years (range 51—86).he median LOS in the ICU was three days (Table 1). One ofhe patients suffered from tinnitus (nr 5) and one needed aearing aid in one ear (nr 3).
indings from the measurement day
he data concerning ventilator treatment, enteral nutri-ion regimens, sedation and opioids for each patient forhe sound-measurement day are presented in Table 2. Seda-
ion denotes treatment with benzodiazepines or propolipidsnd opioids means pharmacological treatment with mor-hine, fentanyl or similar compounds. Enteral nutritioneans that the patient was fed through a tube and that
The sound environment in an ICU patient room 273
Table 2 Ventilator treatment, enteral nutrition, midazolam, propofol and opioids at the time of sound measurement. The ‘‘X’’means that the patient has received the treatment some time during the ICU stay.
Patient ID Ventilator Enteral nutrition Midazolam Propofol Opioids
1 X2 X X34 X X X X5 X X X6 X X7 X8 X9 X X X
10 X X X X1112
(1((
Ip1
13 X X
the nutrition was connected to a pump next to the bed. Sixof the patients stayed only one day in the ICU (Table 1),meaning that these patients described their experiencesfrom the sound measurement day. As the other sevenpatients had an ICU LOS of between three and 66 daystheir sound experiences could be from the measurementday but also from any of the other days spent in theICU.
Table 3 presents the results from the sound measure-ments and a summary of the number of early signs of ICUdelirium for each patient. The overall mean sound levelfor all the 12 patients over the 24-hour period was 53 dB
issf
Table 3 Number of early signs of ICU delirium, disturbing soundsLAFmax for each patient.
Patient ID Early signs ofICU delirium
Disturbing sounds b
1 2 Not disturbed3 0 Not disturbed
5 0 Not disturbed
7 0 Not disturbed
11 7 Not disturbed
2 2 Technical equipmentPatients in the same roomStaff
4 8 Staff
6 1 Sounds in dreamsStaff
8 3 Patient in the same room10 6 Technical equipment
12 0 Patient in the same roomStaffTechnical equipment
9 8 No sound memories
13 7 No sound memories
a Value is missing due to technical problems.b According to interviews.
X X
LAeq) (SD = 1.11) with maximum levels ranging from 82 to01 dB (LAmax) and minimum levels ranging from 31 to 47 dBLAmin). LAF max levels exceeded 55 dB 68—89% of the timeTable 3).
Four patients showed seven or more early signs ofCU delirium, according to the early signs of deliriumrotocol (Table 3) and Tables 4 and 5 present all the3 patients’ signs in more detail. No patient exhib-
ted a behaviour that indicated hyperactive delirium,uch as plucking behaviour, motor restlessness or aggres-ion. A majority of the patients (nine patients) wereully awake at some time during the day and responded
, percent of the time that LAFmax exceeded 55 dB, LAeq and
% Of the timethat LAFmaxexceeded 55 dB
dB (LAeq) dB (LAFmax)
a a a
79% 55 8978% 53 10182% 52 8882% 53 9779% 54 88
83% 54 8879% 51 87
87% 52 8477% 53 9489% 53 93
86% 53 9468% 51 82
274 L. Johansson et al.
Table 4 Number of patients (n = 13) showing according the ‘‘early signs of ICU delirium’’ protocol. The ‘‘X’’ means that a nursehas observed the sign sometimes during the 24 hours of measurement.
ID Never fullyawake
No clearsentences
Did not restpeacefully
No calm andpeaceful look
No period withcalm sleep
Do not respondsadequately
1 X2 X X34 X X X X56 X78 X X X9 X X X X X
10 X X X11 X X12
X
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tticwatwsha
13 X X
dequately to the staff’s requests (10 patients) and aajority (12 patients) also had periods of calm sleep. In
he statistical analysis we found no connection betweenigh number of early signs of ICU delirium and highound levels (LAeq p = 0.63, r = −0.15 and LAmax p = 0.99,
= −0.004).
indings from the interview data
able 3 presents a summary of the disturbing sounds men-ioned by each interviewee. Two (nr 9 and nr 13) did notecall anything concerning sounds or other events from theirime in the ICU. Five were not disturbed by noise, butemembered sounds in different ways. The interviews areresented in categories and subcategories (underlined in theext) (Table 6).
ounds related to the settinghe environment in the patient room was experienced asalm and peaceful by some of the interviewees and quietnough for them to rest and sleep at night. But the envi-onment could also be too calm. In one case, one of thenterviewees described how, on some occasions, he wokep in the middle of the night and found the room too quietnd this silence really scared him. When he woke up, heould not orientate himself at all and he did not know wheree was or what time it was, nor could he contact the staffince he was intubated and tired. He did not see the staffnd no one saw that he was awake. At that moment heelt very lonely and abandoned. Only two patients recalledearing sounds from outside. They heard sounds both from aelicopter landing and explosions related to a buildingroject. Neither of these two interviewees was disturbedy these sounds.
ounds related to the staff
wo of the patients said that they hado memories of sounds related to the staff. However, aajority of the interviewees recalled low sounds as
omething necessary and continuous and that they were
SApr
X
ware but not disturbed by the staff’s presence. Even inases when they did not actually see the staff, they couldear them quietly moving about, carrying out their dutiesnd talking to one another, which made the intervieweeseel safe and secure. This background noise also some-imes helped the patient to distinguish between day andight since the sound level from the staff decreased atight. However, there were times when the intervieweesere disturbed by sounds related to the staff. In theseases they felt helpless and they realised that they hado possibility of escaping from the noise. On some of theseccasions the sound level was important, for examplehen nurses with distinctive voices talked or laughed.
n other cases there were other factors that made theound disturbing and uncomfortable, for example whenhe conversations were too quiet to understand but loudnough to hear. One patient described the experience asollows:
(nr 4)‘‘Then sometimes when you lie there, halfasleep. . .. the staff stand in the door way and joking witheach other, then I thought, are they talking about meor.?’’
Some of the sounds that the patients recalled fromhe ICU concerned dialogues and conversations aboutheir own treatment and care. For example, one of thenterviewees remembered how she heard fragmentary dis-ussions and conversations about her blood pressure whichas too low and ongoing treatment, but she was too tired tosk anything. Other interviewees remembered how the staffalked directly to them, asking if they needed anything oranted help. One patient recalled how the physician once
topped the anaesthesia for a short period and told him whatad happened and about the treatment, which he reallyppreciated.
ounds related to other patients in the same room.ll the interviewees shared rooms with one or two otheratients and the space was divided only by thin fab-ic curtain. It was impossible not to hear what was
The sound environment in an ICU patient room
Tabl
e
5
Num
ber
of
pati
ents
(n
=
13)
show
ing
acco
rdin
g
to
the
‘‘ea
rly
sign
s
of
ICU
delir
ium
’’
prot
ocol
.
The
‘‘X’
’
mea
ns
that
a
nurs
e
has
obse
rved
the
sign
som
etim
es
duri
ngth
e
24
hour
s
of
mea
sure
men
t.
ID
Tens
e
body
posi
tion
Betw
een
cons
ciou
s-ne
ss
and
wak
eful
ness
Wak
ing
wit
han
xiet
yD
iffic
ulti
esin
answ
erin
gM
umbl
ing
spee
chFe
arfu
l loo
k
Tens
e,w
atch
ful l
ook
No
eye
cont
act
Apat
heti
clo
okPa
ssiv
ebe
havi
our
1X
2 3 4X
XX
X5 6 7 8 9
X
X
X10
X
X
X11
X
X
X
X
X12 13
X
X
X
gocpnbnprtouitthfiio
wwaitssb
tcr
SErtufdauf
275
oing on and the patients who recalled such episodesften commented in the interview about the soundsoming from the patients beside them. Some were sim-ly aware but not disturbed by the sounds and they onlyoticed the appearance of the others. Thus, sometimes theyecame involuntary listeners, whether they wanted to orot. Two patients described how several times they heardarts of conversations concerning the other patient in theoom. These dialogues made them both curious and frus-rated since they had to listen to stories without beginningsr ends. These stories gave rise to many thoughts and spec-lations but they had no one to talk to about them. Thellness of the interviewees complicated the situation sincehey were tied to the bed with cables and sometimes a ven-ilator. In cases when there was a lot of noise around, theyad no possibility of shutting off the unwanted sound. Theyound some of this disturbing noise extremely annoying andrritating. The interviewees had to listen to coughing, snor-ng and screaming patients and no one offered them a radior ear protection. One of the participants said:
(nr 8) ‘‘but it was so annoying, this noise all the time, andI couldn’t sleep to escape the noise, it was impossible, itwas so loud it was impossible’’
In addition to the annoying sounds, some soundas experienced as scaring and frightening. One intervie-ee, who was awake and doing relatively well, lay next to
critically ill patient during the night and day she spentn the ICU. She had to listen to all the discussions abouthe progression of the other patient’s illness and hear thetaff carry out advanced treatment. For example, she heardeveral physicians come in and perform a tracheotomy, justehind the curtain. This is what she heard:
(nr 12) ‘‘and then, once, he obviously got so bad that a lotof surgeons came in, I don’t know how many there were,and they didn’t speak in low voices, they spoke loudly anda lot to each other about all these things and illnesses,I know a little about healthcare so. . . I put my fingersin my ears, I didn’t want to listen. Then I heard one ofthe surgeons say: but then we have to do a tracheotomy,then we have to do a tracheotomy. . .and, (whispering),I thought; now they will cut his throat here in the ICU.Yup, they put on operating clothes and they stood thereand discussed things loudly, they didn’t consider whetheranyone was awake.’’
She thought it was awful to lie there, surrounded by allhat noise, and felt helpless and fearful. None of the staffame to her and explained anything or offered her anotheroom and it did not occur to her to ask herself.
ounds related to the technical equipmentven if most interviewees lacked memories of soundselated to technical equipment, some were well aware ofhe sound from the machines. Some sounds were verynexpected and experienced as disturbing and annoying,or example the alarms from the food pump, the infusion
rip and the ventilator. Sometimes these sounds also neg-tively affected their night sleep. When they heard thesenfamiliar sounds, especially at the beginning, many hadrightening thoughts about the meaning of the sound. One
276 L. Johansson et al.
Table 6 Overview of categories and subcategories in relation to sound experiences.
Categories Subcategories
Sounds related tothe setting
Calm and peacefulToo quietHearing sounds from outside
Sounds related tothe staff
No memories of sounds related to the staffAware but not disturbed by the staff’s presenceNo possibility of escapingConversations about the own treatment and care
Sounds related tothe other patientsin the same room
Aware but not disturbedInvoluntary listenersNo possibility of shutting off the unwanted soundScaring and frightening sounds
Sounds related tothe technicalequipment
Lacked memories of sounds related to technical equipmentFrightening thoughts about the meaning of the soundSafe and friendly
Sounds as a part of dreams Sounds integrated into dreams
ottbbasp
tsis
SOaestt
w
S
TcSiebrapcttf
D
TptaeLsrbWttsm
f the interviewees was scared to death when she was lis-ening to the sound from the ventilator and thought thathe alarm indicated that it was about to stop and she woulde unable to breathe. Furthermore some sounds were com-ined with physical contact which made these noises morennoying, for example the automatic blood pressure mea-urement and the treatment with continuous positive airressure (CPAP). One participant remembered:
(nr 10)‘‘. . .yes, it was another sound that disturbed me,when they came in and checked my temperature, it wasso annoying, when they came in with this new machine,and just pushed it in to my ear. . .(sound). . .And it makesa noise. . .I thought that it was terrible. . . And then theyuse some sort of capsule or whatever it is, and then: ‘‘no,it must be wrong’’ and then they put it in the other ear,or so. . .’’
After a whilst, when they got used to the environment,he patients became increasingly familiar with the differentounds. If they recognised the various alarms and sounds andf they knew that the staff took care of the machines theyometimes found the sounds both safe and friendly.
ound as a part of dreamsne of the interviewees remembered sounds but they werell integrated into her dreams. There were no really fright-ning sounds, but they were disturbing and unfamiliar andhe was unable to protect herself from the noise, even if sheried. One of the sounds she heard and mentioned severalimes was a clicking sound. This is her description:
(nr 6) ‘‘and then all the time, I heard these clicks. . . fromsomeone. . . it was a slide projector or. they came back,
over and over again.’’
She never received any explanation of what the soundas or where it came from.
TetT
ummary
he results from the interviews describe the variety andomplexity of the various sounds in an ICU patient room.ometimes a similar sound could be experienced as disturb-ng on one occasion and safe and comforting on another, forxample sounds from the chatting staff or from the patienteside them. It was also obvious that all sounds were expe-ienced subjectively and that the patients had both positivend negative experiences of the sound environment. Theositive sounds, such as those from a quiet working staff,reated feelings of safety, security and familiarity, whilsthe negative sounds, such as those from a sick patient behindhe curtain or noisy technical equipment created feelings ofear, helplessness and anxiety.
iscussion
he sound environment in the ICU and its effects on theatients is a complex area and our results further illustratehat many factors influence both the level of disturbancend the patient’s experience. One factor is the noise lev-ls in the patient room. The results of our study show aAeq noise level of between 51 dB and 55 dB LAeq, which isomewhat lower than previous investigations in similar envi-onments (Akansel and Kaymakci, 2008; Ryherd et al., 2008)ut still high. This also far exceeds that recommended by theHO (WHO, 1999). Another interesting result is the fact that
he LAFmax level exceeded 55 dB between 77% and 89% ofhe measured time for 11 of the 12 patients who were mea-ured. This is alarming since it means that there are very fewinutes per day in which the patient gets peace and quiet.
he two patients (nr 8 and 12) who had the highest lev-ls, 87% and 89% of the time respectively also mentioned inhe interview that they were disturbed by different sounds.hree early signs of ICU delirium were observed in one of
‘rinttpecbTsso(Ita
L
Tafucssapitrit
pgGdloIwabaaTcssbwbdBpatients were included in this study. It is therefore impor-
The sound environment in an ICU patient room
them (nr 8). These two patients had a LOS of only one dayso what they recalled was from the measurement day.
We did not see any correlation in this study between ICUdelirium and number of high sound levels, but that does notmean that there is no such relationship. First, the sampleis small, this study is to be seen as a pre-study, and sec-ond, ICU delirium often develops over time, hours or days,and here we only registered early signs of ICU delirium con-tinuously during one day. The signs these patients showed,or did not show, could be the result from another day ornight with or without high sound levels. Thirdly, there aremany other risk factors already identified as predisposing toICU delirium (Ouimet et al., 2007) and this must be takeninto account. Thus a larger study is needed to exclude possi-ble confounders. The next important step will therefore beto follow a higher number of patients for a longer period,with reference to ICU delirium in connection with high soundlevels and disturbing sounds.
Previous studies have shown that the hospital person-nel themselves produce the majority of the noise in theICU (Akansel and Kaymakci, 2008; Xie et al., 2009). In thisstudy, the interviewees had few negative things to say aboutthe sounds related to the staff even if some gave exam-ples of negative experiences. It is important to rememberthat patients, especially those in the ICU, are completelydependent on the staff. Being a patient treated in an ICU,means being under the control of another and the pres-ence of the staff can be simultaneously both comfortingand disturbing. Almerud et al. (2007) describes how thepatients in an ICU try not to bother the staff, but striveto please and that coping in some way depends on com-pliance with the current rules. The present findings pointto the importance of an involved staff, sensitive to thepatients’ needs. Education about the effects of acousticnoise is also needed, since a previous study has shown thatsuch knowledge is limited amongst ICU staff (Christensen,2005). The results from the interviews, show the connec-tions between specific events involving high noise levels anddisturbance, for example when the staff speak loudly orunexpectedly loud alarms and loud treatments occur. Butas often as the disturbance seems to be related to eventswith high noise levels, it is just as common for other fac-tors to influence the possibility of sleep, rest and calm.Such things for example, were patients snoring, coughingand vomiting in the same room. These annoying soundsmade the whole stay very uncomfortable for the patientand some of them also created feelings of insecurity, fearand helplessness. It was also obvious that noise related tothe next-door patient together with noise from technicalequipment were two of the most annoying and disturbingelements, which is consistent with other recent quantita-tive and qualitative studies (Akansel and Kaymakci, 2008;Almerud et al., 2007). The sound environment in the ICU isunique since most patients there are suffering from severecritical illness or injuries and require advanced and noisytreatment both day and night as well as high levels ofstaff activity. These treatments and caring activities pro-duce noises, both loud and disturbing, some of which werementioned in the interviews, for example the suctioning
procedure (90 dBA) (Jang et al., 2004) and the continu-ous positive airway pressure treatment (CPAP) (57—70 dBA)(Cavaliere et al., 2008). As one of the interviewees narrated,
t‘m
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‘light’’ surgery is also sometimes performed in the patientoom. Such conditions strongly suggest the need for specificnterventions and much more must be done to protect theeighbouring patient. The goal of intensive care must beo create a basis for recovery; not only through advancedechnical and pharmacological treatment but also throughroviding a healing environment (La Torre, 2006; Lowert al., 2002), including peace and quiet. Single rooms, ofourse, would be the best option, but if that is not possi-le, a reduction in the noise level in the rooms is necessary.his can be achieved through making the ceilings and wallsound absorbent, but also through action plans concerningtaff behaviour (Monsen and Edell-Gustafsson, 2005). Sec-nd, technical equipment must be designed to be silentEdworthy and Hellier, 2006; Meredith and Edworthy, 1995).t is unacceptable for machines to be positioned just behindhe patient’s head and produce high noise levels and loudlarm signals.
imitations
he sound experience is related both to the sound levelsnd individual conditions at a specific time. It was there-ore important for us to elucidate the research questionsing both a quantitative and a qualitative approach. Theomparison of ICU delirium and high sound levels might beeen as a pre-study in view of the small sample, whilst theound level measurements and the qualitative part providesn acceptable description of what it is like to lie in an ICUatient room. To achieve good reliability the texts of thenterviews were coded by two of the authors, first by LJ andhen ‘‘reproduced’’ by BL. Reproducibility, or ‘‘intercodereliability’’ measures the consistency of shared understand-ng held by two or more coders and is necessary to ensurehe quality of a content analysis (Krippendorff, 2004).
ICU delirium remains unrecognised in 66% to 84% ofatients whether they are in an ICU, hospital ward, or emer-ency department (Delirium and Cognitive Impairment Studyroup, 2010 (www.icudelirium.org)). The ‘‘early signs of ICUelirium’’ protocol, which is under development, has someimitations since it has not yet been analysed for validityr reliability. However, it captures the signs of a developingCU delirium early on and is an efficient and easy protocol toork with. It is designed primarily to help nurses recognisend identify signs of delirium early since they work at theedside. The protocol is easy to administer and can be seens a complement to other protocols such as the confusionssessment method for the ICU (CAM-ICU) (Ely et al., 2001b).he CAM-ICU screens for signs of ICU delirium only at a spe-ific moment and moreover, the patients have to respond topecific questions, which can sometimes be hard. The ‘‘earlyigns of ICU delirium’’ protocol was developed from a studyy Granberg-Axell et al. (2001), where patients in an ICUere strictly observed for several days. All the patients hadeen mechanically ventilated but they were only observeduring the weaning process or the days after extubation.oth mechanically ventilated patients and non-ventilated
ant to take into account that some of the signs, for example‘no eye contact’’, can be connected to the sedative treat-ent as well as to ICU delirium. Another weakness of the
rotocol is that it is meant to be completed by the nurses inhe patient room. Sometimes the nurses have a great deal too and there might be a risk that they will not always havehe time to identify the signs and/or complete the protocol.
onclusion
he sound level in the patient room in an ICU is too highnd the LAF max levels exceed 55 dB 70—90% of the time.owever, it is not only the high level of sound that is aroblem for the patients. Sounds from to the neighbouringatient and from advanced medical treatments and techni-al equipment are experienced as disturbing and can createeelings of helplessness, excluding the possibilities of find-ng peace and calm which are essential for recovery andell being. In this small sample, no statistical connectionas seen between early signs of ICU delirium and high sound
evels, but more research in this area is needed. This knowl-dge is of great importance both in connection with theevelopment of new ICU units and for the staff who workn them.
onflict of interest
he author(s) declare that they have no competing interests.
cknowledgements
e would like to express our thanks to the patients thathared their experiences with us and Timothy Hsu for hisind assistance in this study.
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