In defence of Respiratory Physiotherapy – Frankland & McWilliams
Introduction
Respiratory dysfunction is one of the most common causes of critical illness necessitating ICU admission (Gosselink et al 2008). Treatment for these patients may include physiotherapy. These treatments may include clearance of secretions, recruitment of collapsed airways, and ventilation/perfusion matching. The definition of chest physiotherapy in the context of critical care generally involves a combination of endotracheal suction, manual hyperinflation and positioning (Barker & Adams 2002). There is substantial literature which supports the role of physiotherapy respiratory management and rehabilitation of critically ill patients although there is a paucity of randomised controlled trials in this area and trials examining patient outcomes (Denehy & Berney 2006). This can lead to questions being raised regarding the effectiveness of physiotherapy within critical care. Added to this a recent article by Templeton & Palazzo (2007) suggested that chest physiotherapy appeared to prolong the duration of mechanical ventilation. This has led to an increase call for physiotherapists to prove the effectiveness of their interventions and justify their role within critical care across the UK. The efficacy of physiotherapy in acute and critical care has been studied extensively and there is moderate to strong evidence in support of its role (Denehy & Berney 2006).The physiotherapist is skilled in a multi-system patient assessment including the management of neurological, orthopaedic and musculoskeletal complications. This makes the role of the physiotherapist unique and extremely highly specialised in comparison with the nurse and the respiratory therapist. A snapshot appraisal of some of the more recent evidence will now be reviewed. A more detailed literature review was done by Denehy & Berney (2006) and Gosselink et al (2008).
Search strategy
The data bases Medline/ Cinahl/ Embase/ Chest/ Respiratory Medicine/ Thorax and European Respiratory Journal were searched using the search terms “Physiotherapy” “Critical Care” “Intensive Care” “Chest Physio” “Manual Hyperinflation” “Positioning” “Physical therapy”.
The search was limited to articles published in English to ensure accessibility to the authors and to articles published after 2000. The strength of the evidence will be evaluated using the system proposed by McIntyre et al (2000) (appendix 1).
Literature review
Physiotherapy and respiratory care
The aim of physiotherapy is to decrease the patient’s dependency on the ventilator to improve residual function, assist in airway clearance, and restore his/her respiratory and physical independence (Gosling et al 2008). This includes minimising post-operative pulmonary complications thereby reducing patient morbidity and preventing a prolonged hospital admission (Clini & Ambrosino 2005). To achieve this objective, physiotherapists use a variety of techniques some of which are discussed here.
Manual Hyperinflation
One of the techniques used is manual hyperinflation (MHI). This is used by physiotherapists with the aim of increasing alveolar oxygenation, reversing atelectasis or mobilising pulmonary secretions (Jones 1997). Patman et al (2000) completed a randomised controlled trial which investigated the effects of MHI on lung compliance (CL) and arterial oxygen to fraction of inspired oxygen ratio (Pao2:FIO2) and alveolar-arterial oxygen tension difference (A-a) PO2 in (n=100) medically stable mechanically ventilated patients who had undergone coronary artery surgery (CAS). The results showed that MHI increased lung compliance and improved gas exchange.
Randomisation procedure was described and sample characteristics confirmed homogeneity, both of which illustrated rigour of methodology and internal validity of its findings. Within this study, the dose for MHI was set at four minutes in the intervention group. In the author’s clinical practice MHI may be used to assess compliance, mobilise secretions in various positions, then could be followed by recruitment. This treatment would undoubtedly vary and sometimes take more than four minutes therefore the positive result from this study could possibility be further enhanced with some patients. In addition, duration and frequency of MHI cannot be prescribed generally as all patients present with different treatment needs. The study did not investigate the improvements/changes after 60 minutes therefore MHI for long term results remains unclear.
Patman et al (2000) provides good level 1 evidence, suggesting that MHI following surgery on ventilated subjects can have significant effects. In clinical practice MHI is not done routinely on all patients, patients have to be carefully selected; this requires a therapist who has had significant training and competence checking to perform this treatment.
To continue the theme, a prospective, randomised, controlled double cross over study by Berney & Denehy (2002),was completed using ventilated subjects (n=20) with 2 groups over 2days. Treatments were performed twice daily, with 2 hour rest periods in between. On the following day the sequence was reversed (Table 1). They concluded that MHI and ventilator hyperinflation (VHI) both improved static lung compliance and helped to clear similar amounts of secretions, although it is acknowledged a relatively small sample size was used (n=20) which would limit the significance and generalisation of these findings
Day 1 / am / Pm / Day 2 / Am / PmSide lying / MHI / VHI / Side lying / VHI / MHI
VHI / MHI / MHI / VHI
Table 1 Berney and Denehy (2002)
The study advocates that VHI or MHI could be used to produce the same yield of sputum. In clinical practice the risks and benefits would have to be assessed for each patient. For example, a patient on a high PEEP who is sensitive to disconnection from the ventilator may require VHI, alternatively the use of MHI by the physiotherapist allows for a proprioceptive feel of the compliance and also allows for different techniques to mobilise secretions and recruit which would not be regimented to a set procedure as on a ventilator.
Assessing the strengths and limitations, it appears to be a level II study and provides good evidence highlighting that patients have shown improvements however, only an experienced physiotherapist should carry out this treatment as evaluation of the risks versus the benefits cannot be ignored. The results of the Berney and Denehy (2002) study is consistent with previous finding by Patman et al (2000).Other authors have also demonstrated that MHI may prevent, or when present re-expand atelectasis (Stiller et al,1990; Rothen et al, 1995)increase secretion clearance (Hogson et al, 1999) and reduce the incidence of nosocomial pneumonia in ventilated patients (Ntoumenopoulos et al, 2002) adding further evidence to the results.
Ventilator Acquired Pneumoniais common within the critically ill adult population and is defined as pneumonia which develops at least 48 hours after initiation of ventilation. Incidence rates have been reported in the region of 25% and when present, are associated with prolonged hospital stays and mortality rates between 33-50% (Niederman, 2006). As well as treating pneumonia, there is evidence to suggest physiotherapy is effective in preventing the onset of VAP. In astudy by Ntoumenopoulos et al (2002), subjects receiving chest physiotherapy (table 2) had a significantly reduced incidence of VAP (8%) compared to controls (39%). Despite this no significant differences were observed in terms of ICU length of stay (LOS), period of mechanical ventilation or mortality, although the study may not have been appropriately powered to assess these additional variables. It was however identified those patients who developed VAP patients had a significantly longer duration of mechanical ventilation (p=0.02) and a higher incidence of tracheostomy (p=0.04). Despite the relatively small sample size (n=60) the study was appropriately powered to detect a 20% reduction in VAP levels and subjects were well matched and confirmed homogeneity. This study provides level II evidence with physiotherapy reducing the incidence of VAP.
Table 2
Physiotherapy group / Control “sham” physiotherapyChest physiotherapy = gravity assisted drainage, chest wall vibrations, and airway suctioning twice per day / “sham” physiotherapy = cardiopulmonary assessment and musculoskeletal movements
Within Critical Care, not only do patients present with VAP, they also can develop acute lung injury (ALI). Baker and Adams (2002) undertook a randomised controlled trial (n=18) to understand and quantify the effects of 3 modes of single treatment in chest physiotherapy in an acute lung injury patient group. Group 1- suction only, group 2- positioned and suctioned, group 3- positioned, manually hyperinflated and suctioned. The outcome measures were PaCO2, PaO2: FiO2 ratio SvO2, BP and HR. Baseline and 10, 30, and 60 minutes post treatment data were recorded.
Table 3
Group 1- suction only / Group 2-positioned and suctioned / Group 3- positioned, MHI and suctionedPaCO2 / Increase with a return to normal in 1 hour / Increase with a return to normal in 1 hour / Increase with a return to normal in 1 hour
PaO2:FiO2 ratio / No significance was demonstrated / No significance was demonstrated / No significance was demonstrated
SvO2 / Baseline = 74.4.
mean values
10 mins =73
30 mins = 73
60 mins = 72 / Baseline = 62.6mean value
10 mins is = 63.2
30 mins = 61
60 mins = 59.6 / Baseline= 71.8
10 mins = 73.3
30 mins = 70.2
60 mins = 70.9
BP / No difference / No difference / No difference
HR / No difference / No difference / No difference
The main study findings did not reveal any major significant differences in intervention from the single physiotherapy treatment.
Within the Baker and Adams (2002) limitations are identified as a small sample size and that only a single treatment within a series of potential treatments was investigated. This makes it difficult to extrapolate too widely the findings. This also questions ethics; the physiotherapists should provide the necessary treatment for that patient, not a regimented application to match a study. For example, a patient may only be appropriate for suction due to high pressures or instability but may have been randomised to group 3. This would affect results as the study is looking at single physiotherapy treatment and not researching effects with appropriate treatment making it difficult to generalise to clinical practice.
Within this study all variables remained constant within the hour following physiotherapy which improves the reliability and validity of the study. Approval from the ethics committee was also used.
Within the authors’ clinical practice the physiotherapy team adhere to practice guidelines which advise caution with ALI or Acute Respiratory distress Syndrome (ARDS) as evidence, and experience confirms the de-recruitment effect. This can be explained by the loss of PEEP on disconnection from the ventilator and the sheer stresses following manual hyperinflation (MHI) causing further damage. However the clinician has to balance the risks/benefits and clinically evaluate each patient for safety and effectiveness. It is possibly the techniques and frequency at which secretions are cleared that becomes important - this highlights the clinical reasoning skills physiotherapists possess to bring about a safe outcome.
The importance and skill required in assessing patients individually at each stage of the episode of care including onset of illness to rehabilitation, then modifying their treatments accordingly cannot be overstated.
Within critical care patients present with numerous different diagnoses and complications. Spinal cord injuries are one of the more challenging scenarios a physiotherapist may be presented with. With cord injuries approx 36%-83% present with respiratory complications (Berney et al 2002). The physiotherapist can be heavily involved as respiratory concerns and pneumonias are common (Ledsome and Sharpe 1981).
A retrospective case control design (n=7) was undertaken by Berney et al (2002) to determine which course of treatment resulted in a difference in length of stay in critical care foracute quadriplegic patients, in addition to see if an on-call physiotherapy service for critical care patients was cost effective.
The 2 differing types of treatment were group (A), extubation and intensive physiotherapy including an overnight on-call service, or group (B).just tracheostomy. Berney et al (2002) concluded that if extubation and intensive physiotherapy is undertaken for suitable patients, the length of stay in intensive care can be significantly reduced.
Results Table 4. Berney et al (2002)
Group (B) Tracheostomy / Group (A) Extubation and intensive physiotherapyOnce daily physiotherapy, composed of gravity-assisted positioning, MHI and suctioning / Received physiotherapy consisting of IPPB, gravity-assisted positioning and assisted coughing as required over a 24 hour period
5 of the 7 patients received on call overnight physiotherapy treatment, with an average of 5 sessions over a total of three nights
Mechanical ventilation was significantly longer in the tracheostomy group (p=0.006) / Decrease length of stay (LOS) (P=0.02)
This study provides level III evidence which shows a decrease in bed occupancy with intensive physiotherapy and on-call. In clinical practice, the amount of staffing and time to provide what is required for patients in critical care is an on going problem. However if considerable cost saving for critical care is made by the use of more physiotherapy expertise,this couldsignificantly reduce any added cost of providing an after hours on-call service.
An extremely controversial study was published by Templeton & Palazzo (2007). This was to examine if chest physiotherapy prolongs the duration of ventilation in the critically ill ventilated patient. This was a single centre, single blind prospective randomised controlled trial with (n=180) patients. The results showed that there wasa significant prolongation of median time to become ventilator free among patients receiving physiotherapy.
Within this study criticisms can be made, for example only 5 of the 44 references are within the 5 year relevance bracket- 39 references being very old. This lack of significant up to date evidence in this study questions the very relevance and validity of this study. Questions could also be asked why was the study started in 1997 and not published for 10years, this would question the papers relevance to modern clinical practice.The study fails to address the potential for differences between the 2 groups analysed, in fact 1 it appears that the physiotherapy group had much “sicker” patients in allocation, for example an increased number of smokers, emergency surgical admissions, higher APACHE II scores on admission and far more respiratory failure patients (22 compared to 16). This would make the study biased and flawed as the homogeneity illustrates no rigour questioning internal validity.
Within the Templeton & Palazzo (2007) study, the article failed to clarify the term “chest physiotherapy” with confusion around the actual definition of this treatment, with some treatments actually being performed by nursing staff. This could therefore question the quality of interventions being delivered and may represent an analysis of the effectiveness of nurses in delivering chest care, not the effectiveness of physiotherapy. . Further questions are raised regarding the results of the study, which were presented on an interim analysis basis(cant remember what was meant by this bit) The study claims that physiotherapy had no effect on mortality and length of stay however it can be assumed that the study is not robust enough to make this claim. This study is a level 1 but due to the methodological flaws it drops to a level III.
Conclusion
The exact role of physiotherapy varies across critical care units, although there are common themes in which they play a part. Specific areas include respiratory assessment and treatment, joint care, exercise and rehabilitation and more recently early mobility programmes. In certain areas physiotherapists have also developed more extended roles such as weaning, extubation and decannulation, performing bronchoscopies and supplementary prescribing to name but a few. Despite a long history of physiotherapy within critical care there remains a lack of high quality evidence supporting many of these interventions. To address this issue the European Respiratory Society (2008) recently published recommendations for physiotherapy interventions for critically ill adult patients. This paper aims to explore some of these specific issues further to provide evidence for the important role physiotherapists play in this area. They also recommend studies on the journey or episode of the patient through illness to rehab to home as this is more pertinent to the patient and family rather than studies that are plagued with variables and ethics.
Due to the demand for rigorous and reproducible protocols it has proven extremely difficult to fully evaluate the effect of ‘chest physiotherapy’ interventions. In fact, the term chest physiotherapy itself has seen numerous definitions in the literature over the years. These have ranged from simple positioning and suctioning to programmes of alternate side lying, manual hyperinflation, manual techniques and suction. This automatically reduces the quality of any evidence, as physiotherapy delivered within the UK does not follow any such prescription, instead being individual patient specific and adaptable both between and within treatment sessions. Physiotherapists are highly trained professionals and perhaps part of the problem is the realisation from other professionals what training we possess. We rely on finely tuned skills in respiratory assessment and clinical reasoning to allow this adaptability and specificity of there interventions. Nonetheless, there are numerous studies demonstrating the effectiveness of individual components used by physiotherapists within their treatments. In recent years there has also been an increased emphasis placed on the importance of rehabilitation within critical care, an area physiotherapists are perfectly placed to lead and drive forward. This has subsequently led to a specific focus on studies into early and structured rehabilitation interventions. Although this further enhances the evidence base for physiotherapy within critical care, it is important not to forget the vital role they still have within respiratory care and the need for more evidence to prove the effectiveness of these interventions. It is understandable for physiotherapists to feel aggrieved by a flawed article questioning there effectiveness within critical care, the Templeton and Palazzo article does serve as a warning and sign of the modern NHS, where more questions are being asked and there is an increased demand for evidence, not just for allied health professionals but for all health care professionals is all settings.