PHYSIOTHERAPY IN THE INTENSIVE CARE UNIT

Physiotherapy  is  reported  to  be  an  integral  part  of  patient  management  in  the  intensive  careunit  (ICU)  of  hospitals  in  industrialised  countries.  There  is  substantial  literature  whichsupports  the  role  of  respiratory  management  and  rehabilitation  of  critically  ill  patients,although  there  is  a  paucity  of  randomised  controlled  trials  in  this  area  and  trials  examiningpatient  outcomes.  The  aims  of  this  review  are  to  present  the  current  evidence  for  the  role  ofphysiotherapists in the adult ICU. The efficacy of ‘chest physiotherapy’ on short-term patientphysiological outcomes has been studied extensively and there is moderate-to-strong evidencein  support  of  its  role.  The  safety  of  physiotherapy  treatment  in  ICU  has  also  recently  beenestablished.  In  addition,  there  is  growing  evidence  for  the  role  of  exercise  rehabilitationbeginning  in  ICU  and  extending  to  beyond  ICU  discharge.  Urgent  research  is  required  byphysiotherapists to establish the effectiveness of such treatments.

Keywords:Chest physiotherapy, exercise, intensive care, non-invasive ventilation, rehabilitation

Intensive care is a dynamic environment where phys-iotherapists are  vital  members of  the multidiscipli-nary  team providing  a  spectrum of  care from acuterespiratory to rehabilitation.The education and training of physiotherapists andtheir  role  in  relation  to  other  health  professionalssuch   as   nurses   and   respiratory   therapists   variesgreatly. This withstanding, physiotherapy is reportedto  be an integral  part of patient  management  in  theintensive care unit (ICU) of hospitals in industrialisedcountries.1The aims of this review are to present thecurrent evidence for the role of physiotherapists in theadult  ICU  in  relation  to  respiratory  managementincluding  non-invasive  ventilation  (NIV),  exercise,and  short  and  longer  term  rehabilitation  of  patients.Literature  searches  were  performed  using  the  data-bases MEDLINE and CINAHL (cumulated index tonursing and allied health literature) with appropriatesubject headings including intensive care, rehabilita-tion,  physiotherapy, physical  therapy, critical care,critical  illness, chest physiotherapy, manual  hyperin-flation and exercise; searches were limited to English language. The reference lists of extracted articles werealso reviewed.Several surveys report on specific  physiotherapypractice  in  the  ICU;2–4generally,  these  are  limited  torespiratory  management.  However,  the  assessmentand management of neurological and musculoskeletalcomplications form an important part of the physio-therapist’s role.1,5It is this individualised, multisystempatient assessment and treatment that defines the roleof physiotherapists compared with respiratory thera-pists  and  nurses.  Physiotherapists  may  be  involvedwith  specific patient positioning,  suction,  mobilisa-tion,  exercise,  passive  movements,  manual  airwayclearance  techniques,  manual  (MH) and ventilatorhyperinflation (VH), NIV and weaning.1,6–8The coun-try of origin of published research reflects differencesin  types  of  healthcare  professionals  employed  in  theICU, with research from the US predominatelyreporting respiratory therapist roles. In the UK, partsof Europe and Canada, South Africa, and Australia,the  role  of  physiotherapists  encompasses  respiratoryas  well  as  neurological  and  musculoskeletal  patient management.1,8Factors influencing   physiotherapyrepresentation in the ICU also include the size of theunit, levels of expertise and staffing, and educationalprofile of physiotherapists.8,9Additionally, the percep-tions of physiotherapy and referral attitudes of inten-sivists  may  also  impact  upon  their  role.7Rationaleand  evidence for the  role of physiotherapy in refer-ence to the techniques listed above follows withreview under specific subheadings.

CARDIORESPIRATORY MANAGEMENT

The  goals  of  respiratory  physiotherapy  managementare to promote secretion clearance, optimise oxygena-tion,  improve  lung  volume  and  prevent  respiratorycomplications  in  both  the  intubated  and  sponta-neously  breathing  ICU  patient.10The  rationale  fortreatment  of  intubated  patients  is  based  upon  theeffects  of positive  pressure  ventilation  on  respiratoryand  cardiovascular  systems  and  the  impaired  func-tion of the mucociliary escalator.11The resultant dis-turbance  of  normal  secretion  clearance  potentiallyleads to sputum retention with a subsequent increasein airways’  resistance  and  work  of  breathing. Thesepatients are at particular risk as the incidence of ven-tilator-associated  pneumonia  increases  substantiallyfollowing 24 h of mechanical ventilation.12The efficacy of ‘chest physiotherapy’, defined vari-ously as combinations of positioning, MH, VH, andpercussion  and vibrations, on  short-term patientphysiological outcomes has been studied   exten-sively.13–17Table 1 summarises this research for studiesperformed  in  the  last  5  years.  There  is  moderate-to-strong  evidence  (NHMRC  level  II  and  III)18to  sug-gest   that  physiotherapy treatment is effective in:recruiting  alveoli;16,19improving secretion clear-ance;13,14compliance;13,14,20airway   resistance;21gasexchange;22and  reducing  the  incidence  of  ventilator-acquired pneumonia.23The technique which has beenincluded  in  the  majority  of  this  research  is  manualhyperinflation. The most significant finding in rela-tion to ‘chest physiotherapy’ treatment in the ICU isthat it has been found to be safe, with adverse physio-logical changes (APCs) reported in only 29 of 12,800physiotherapy  treatments  from  five  Australian  ter-tiary hospitals (0.22%).24Several studies have examined the effects of MH onsecretion removal, oxygenation and static pulmonarycompliance.  The  results  have  been  difficult  to  inter-pret  and  compare  due  to  variations  in  definition  ofMH, different circuits that have been used, and incon-sistency  in  therapists’  technique and treatmentdosage.5,25,26In  the  last  5  years,  several  authors  have contributed to defining further the technique of MHas  used  by  physiotherapists  and  added  considerableknowledge to the body of literature in this area.13,27–31Summaries and recommendations from their findingsare  given  in  Table  2.  For  an  evaluation  of  researchprior  to  2000,  readers  are  referred  to  an  extensivereview of MH published in 1999.5Beyond this, the use of VH has been compared withMH,  and  effects  on  static  lung  compliance and wetweight of sputum produced have been found to be simi-lar. The use of VH allows the operator to control airwaypressure  limits,  monitor  delivered  volumes,  and  main-tain  positive  expiratory  pressure.  This  research  offerssupport to the use of VH as an alternative to MH, anddescribes the technique of VH.20There is consensus inthe  critical  care  literature  supporting  the  protectiveproperties of positive end expiratory pressure (PEEP) inpreventing ventilator-induced lung injury;32as VH canbe performed without disconnection from PEEP, phys-iotherapists must now consider the potential risks asso-ciated with delivering large tidal volume breaths using amanual  resuscitation  bag,  when  potentially  the  samebenefits can be achieved by using the ventilator.Ntoumenopolous and colleagues23compared phys-iotherapy  treatment  versus  a  sham  treatment  in 60intubated and ventilated critically ill patients. Physio-therapy  treatment  comprised  chest  wall  vibrationsand specific positioning (no MH). The authors foundthat the incidence of nosocomial pneumonia was 31%less in the group who received physiotherapy,although no difference in time on mechanical ventila-tion or time  in  the  ICU  was  found.  This  is  the  firststudy  to  compare  outcomes  for  patients  of  receivingphysiotherapy treatment in the ICU.23This research follows on from previous work by thesame  author examining  the effect of physiotherapytreatment  on  nosocomial  pneumonia  in  46  patients,which   found   that   the   more   severely   ill   patients(APACHE 2 score > 15), and those ventilated longerthan 7 days,  showed  a  trend  toward  benefiting  fromphysiotherapy; however, the relatively small  samplesize limited the generalisability of this work.17Evidence  relating  to  the  cardiovascular  and  meta-bolic effects of physiotherapy treatment in the ICU isconflicting.  Berney  and  Denehy33found  that  chestphysiotherapy  including  ventilator  hyperinflation  inside-lying  did  not significantly  increase VO2in  20intubated adult ICU patients. This result was not con-sistent  with  previous  similar  work;34however,  theeffects of physiotherapy  treatment  on  VO2had  notpreviously been isolated from those of positioning thepatient and airway suctioning.  Providing effectivephysiotherapy management without additional stresson  the cardiorespiratory  and  metabolic  systems isvital in critically ill patients.

In several studies performed examining ‘chest phys-iotherapy’ in patient populations, no adverse cardio-vascular consequences have been encountered:13,14,16,33measures of heart rate (HR), cardiac output (CO) andmean  arterial  blood  pressure  (MAP)  were  recordedduring  and  after  physiotherapy  including  MH  inthese studies. Conversely, others  have recordedchanges in HR, MAP and pulmonary vascular resis-tance in patients following coronary artery surgery,22and in an animal model.35Comprehensive reviews ofhaemodynamic responses to some aspects of physio-therapy  in  the ICU are available.36Based  upon  thefindings outlined above, care must to taken to moni-tor the patient at all times and to treat only if the sta-bility of the cardiovascular system can be maintained.In a recent audit of APC during 12,800 physiotherapytreatments, changes to blood pressure (BP) in patientson  inotropes  was  the  most  common  finding  in  thesmall number of treatments where APC occurred.24It  is  important to note that  patient  demographics  inthe studies discussed above did not include acute respi-ratory  distress  syndrome (ARDS).  Recent  evidence  toprovide  lung  protective  strategies, including  moderate-to-high PEEP and  low  tidal  volumes  for  patients  with ARDS  also  supports  the use of  periodic  recruitmentmanoeuvres to improve oxygenation and reduce mortal-ity.32However, currently,  the  efficacy of  such  strategiesmay be limited to patients with non-pulmonary ARDS.37There  is  an  abundance  of  evidence  to  support  therole of NIV in the ICU in the management of patientswith  acute  hypercapnic  respiratory  failure  and  acutecardiogenic  pulmonary oedema;  however, contro-versy  exists  regarding  its  role  in  the  management  ofhypoxaemic respiratory failure.38Recent research sup-ports  the  use  of  NIV  in  the  prevention,  rather  thanthe   treatment, of  hypoxaemic  respiratory  failure,where  failure  to intubate  patients may lead  toincreased mortality  in  the  NIV  group.39Synthesis  offindings from the NIV research to date is confoundedbydiffering treatment regimens and the ability of staffto apply the technique effectively. NIV is an evolvingspecialty in ICU which requires specific training andapplication  by  professionals  skilled  in  patient  man-agement. Although the role of physiotherapists in thedecision-making  process  and  application  of  NIVvaries world-wide, physiotherapists are ideally suited tothis role through their  combined  skills  in physiology,knowledge of equipment and clinical management.

The use of continuous  positive airway pressure(CPAP)  in preventing   intubation in  hypoxaemicpatients  following  abdominal  surgery  was  comparedwith  administration  of  50%  oxygen  in  209  patients:those who received CPAP had a lower intubation andpneumonia   incidence and a shorter ICU stay.40Findings from  this  randomised, controlled   trial(RCT)  support  the work  of previous  authors55andextends   the effectiveness of CPAP in influencingimportant outcomes  in  hypoxaemic  patients follow-ing abdominal surgery.In order to contribute further to this growing area,physiotherapists need to become involved in researchinto  the  role  of  NIV  (including  CPAP)  in patientmanagement,  and to be  strong  advocates  for  theirknowledge  and  ability in its application. Further-more, physiotherapy undergraduate education shouldinclude the principles of management associated withNIV, which can be built upon at postgraduate level

EXERCISE AND REHABILITATION

Rehabilitation in the ICU has been defined in a posi-tion paper by The European Respiratory Society as aprocess  to  achieve  optimal  daily  functioning  andhealth-related quality of life of individual patients asmeasured by clinically and/or physiologically relevantoutcome  measures.41The  methods  by  which  thesebroad  aims  are  achieved  vary  significantly  betweenand  even  within  countries.  There  is  substantial  pub-lished literature which supports the role of rehabilita-tion  of  critically  ill  patients,  although  there  is  apaucity  of  both  randomised  controlled  trials  in  thisarea and research examining patient outcomes.25Theprogress  of  intensive  care  medicine  has  dramaticallyimproved  survival  in  critically  ill  patients;32,42suchimprovement  is,  however,  associated  with  decondi-tioning, muscle weakness, dyspnoea, depression, anda  reduction  in  quality  of  life.  Ultimately,  the  goal  ofintensive care is quality long-term, rather than short-term  survival, but  international  literature reportspoor  quality  of  life  and  physical  outcomes  in  ICUsurvivors compared to age-matched controls.43Changes  in  patient  conditions  result  from  pro-longed  periods  of  inactivity,  catabolism  and  drugadministration   (e.g.   sedative   and  neuromuscularblocking  agents, corticosteroids);  these  factors  con-tribute to weakness that can last for months followingICU   discharge.44Severe   and   prolonged   weakness(critical  illness  neuromyopathy)  is  present  in  up  to25%  of  patients  mechanically  ventilated  for  greaterthan 7  days.45Critical  illness  neuromuscular  abnor-mality (CINMA) is also an independent predictor of prolonged  weaning  from  mechanical  ventilation.46Among  treatment  strategies  including  intravenousimmunotherapy, normalising blood glucose and min-imising  exposure  to  drug  therapy,  physiotherapy  hasbeen   advocated.45Exercise   in   the   ICU   aims   tomobilise patients early and facilitate weaning,47opti-mise oxygenation,48and improve function by increas-ing     strength     and     endurance.49The     role     ofphysiotherapists  in  the  application  of  exercise  varieswidely  in  response  to  scant  evidence.  Primarily,  noreliable and valid exercise outcome measure has beendeveloped  to  aid  exercise  prescription  and  measurepatient  outcomes,  making  research  in  the  area  diffi-cult. As a result, there are currently no guidelines forrehabilitation  of  ventilated  patients  and  few  trialsinvestigating   effectiveness.   Jones   and   colleagues44studied 69 ICU patients at discharge provided with a6-week  self-help  rehabilitation  manual  (including  aself-directed  exercise  programme)  compared  to  con-trols  (n=  57),  and  found  that  scores  on  the  SF-36weresignificantly  better  for  the  intervention  groupthan controls. There is an urgent need for research byphysiotherapists  into  the  long-term  benefits  in  theterms  of  physical  function  and  quality  of  life  out-comes  of  ICU  survivors  using  specifically  designedexercise  programmes  in  ICU  survivors.  Despite  thepaucity  of  evidence,  the  general  consensus  is  thatrehabilitation  should  commence  as  soon  as  possibleduring ICU admission.For ventilated patients in the ICU, the efficacy anduse of physiotherapy interventions to improve decon-ditioning  and  weakness  is  variable.  There  is  limitedevidence  that  passive  stretching  is  effective  in  main-taining muscle length or joint range of motion, mostworkhaving  been  performed  using  animal  models.Furthermore,  there  are  no  data  reporting  the  effec-tiveness of splinting to achieve the same aims of treat-ment.  Despite  this,  there  is  anecdotal  evidence  thatphysiotherapists  still  use  these  techniques:  furtherresearch  is,  therefore,  required.  The  use  of  the  tilttable in long-stay and neurological patients has beenreported  by  67%  of  Australian  ICU  physiotherapistssurveyed;50the  aim  of  using  a  tilt  table  in  rehabilita-tion is to re-introduce patients to the vertical position,especially following prolonged immobility. In the sur-vey  by  Chang  and  colleagues,5061%  of  physiothera-pist respondents used tilting less than once per monthor once a year. Reasons given for this were that othertechniques  were  used  in  preference  (46%  of  respon-dents), or that it was not clinically indicated (32% ofrespondents).   Physiotherapists   in   high-level   ICUs(level 3) used tilting more than in other units, reflect-ing  the  longer  term  patient  demographics.  Theseresults highlight the lack of sound evidence for tiltingcurrently available, and the preference for use of early mobilisation such as assisted standing or marching onthe spot exercise.Mobilisation  can  refer  to  many  different  activities,the  exact  definition  of  which  are  difficult  to  find.Commonly, there is a hierarchy in accepted mobilisa-tion  exercises  in  the  ICU51and  this  may  include  bedexercises,  sitting  over  the  edge  of  the  bed,  standing,transferring,  and  walking  on  the  spot.52These  exer-cise strategies reflect specificity of training for futurefunctional   tasks.   Mobilising   critically   ill   patientsrequires  an  initial  comprehensive  assessment  of  thepatient’s cardiorespiratory status. Until recently, therehave  been  no  published  guidelines  for  patient  safetyand  readiness  for  mobility.  Stiller  and  Phillips51rec-ommend  cardiovascular  and  respiratory  parametersto be assessed prior to mobilisation (Table 3) in con-junction with a full patient assessment and use of clin-ical  reasoning.  The  authors  subsequently  used  theseguidelines  to  study  the  effects  of  mobilisation  onphysiological  parameters  in  31  ICU  patients  andfound   that   significant   increases   in   HR   and   BPoccurred during exercise while non-significant reduc-tions  in  oxyhaemoglobin  saturations  were  recorded.The authors concluded that, using the guidelines pre-viously developed, they were able to institute mobili-sation  safely  and  effectively  in  the  population  ofpatients  studied.  Monitoring  during  and  after  exer-cise  is  vital  and  recommendations  are  to  observepatient  appearance,  excessive  changes  in  HR,  BPSpO2, ECG arrhythmias, and patient appearance.51Active exercise (including muscle training) has beenshown  to  improve  6-min  walking  distance  signifi-cantly  more  than  standard  care  in  80  patients  withchronic obstructive pulmonary disease and acute respiratory  failure.53The  work  of  Nava53supports  theprescription of specific exercises such as bilateral armelevation,  hip/knee  flexion,  and  knee  extension  exer-cises, in addition to functional activities such as sit-to-stand,   and   walking   on   the   spot,   for   intubatedcritically ill patients.Whilst  the  need  for  exercise  rehabilitation  in  ICUhas been recognised,47there is no clinical research thatidentifies  the  most  effective  mode,  intensity  or  fre-quency of exercise prescription. As a result, exercise isapplied by physiotherapists in the ICU using physio-logical  principles,  underpinned  by  clinical  trainingand a comprehensive understanding of pathophysiol-ogy.Physiotherapists are well placed to provide exer-cise  but,  again,  there  is  an  urgent  need  for  researchinto exercise outcome measurement and the value ofspecific  exercise  regimens,  particularly  in  intubatedand  ventilated  patients.  In  the  acutely  ill  patient,  forexample, the value of upper and lower limb strength-ening  exercise  should  be  measured  together  withpatient oxygen demands during and after exercise.

CONCLUSIONS AND RECOMMENDATIONS

Rationalisation  of the  limited  government  resourcesto  critical  care  has  demanded  that  physiotherapistsprovide  evidence  for  their  continued  role  in  patientmanagement.54Physiotherapy  in  the  ICU  needs  todemonstrate  cost-effective  returns.  In  reviewing  theliterature,  a  lack  of  randomised  clinical  trials  is  evi-dent. Previously,  physiotherapists  have  concentratedon  examining  the  effects  of  their  treatment  interven-tions  on  short-term  physiological  outcomes:  authors attempting  to  determine  the  effects  of  treatment  onlonger  term  outcomes  have  been  limited  by  smallpatient numbers. The benefits of physiotherapy treat-ment may be better evaluated as a part of a packageof  care  that  includes  mobilisation,  positioning,  andvariable  nurse-to-patient  ratios.  It  is  plausible  thatphysiotherapy  treatment  as  a  part  of  a  multidiscipli-nary  approach  to  care  is  integral  in  promoting  lungrecruitment,  reducing  the  incidence  of  ventilator-acquired  pneumonia,  facilitating  weaning,  and  pro-moting safe discharge from the ICU.Obtaining   evidence   and   implementing   practiceremain a major barrier for physiotherapists who workin  the  ICU.  Ntoumenopoulos  and  colleagues23haveprovided sound evidence for the role of physiotherapyin  reducing  the  incidence  of  nosocomial  pneumoniain  60  ICU  patients:  this  research  was  published  in  ajournal  with  a  high  impact  factor.  It  would  be  inter-esting  to  know  whether  the  results  have  influencedintensivist physiotherapy referral attitudes. Certainly,physiotherapy referral in the unit where this researchwas undertaken has not changed (personal communi-cation)  highlighting  that  implementing  change  ofpractice based on evidence can be difficult. Given thatnearly 60% of ICU directors from five different coun-tries  felt  that  certain  aspects  of  physiotherapy  work(predominately airway clearance) could be covered bynursing  staff,  it  is  imperative  that  physiotherapistspromote their broader clinical role.7Research  measuring  outcomes  will  become  moreavailable as  physiotherapy  students  embrace  a  grow-ing research   culture  in   university physiotherapyschools  and  clinical  training  facilities,54and  morephysiotherapists  undertake  postgraduate  degrees  incardiorespiratory  specialty  areas.  Research  shouldfocus  on  the  broad  aspects  of  physiotherapy  servicedelivery  in  the  ICU  as  a  part of  a multidisciplinaryteam using outcomes such as time on mechanical ven-tilation,  time  in  ICU,  re-admission  to  ICU,  and  dis-charge  destination,  together  with  quality  of  life  andmeasures  of  physical  function.  Multicentre  researchin the form of a randomised controlled trial evaluat-ing the effectiveness of ‘chest physiotherapy’ would beideal, but extremely costly and virtually impossible toimplement  due  to  differences in  both  medical  andphysiotherapy clinical practices and disparity in rolesand  autonomy of  therapists  within ICU  environ-ments. In addition,  the  numbers  of  patients  requiredto find a statistical difference in such a study mean itmost  likely  will  never  be  performed.  Physiotherapymembership  of,  or  recognition  by,  local  critical  caresocieties would enhance support and infrastructure toundertake  research  and help  to  facilitate  changes  tophysiotherapy practice in critical care, based upon thebest available evidence.