Service evaluation of an outpatient exercise class after critical illness

Introduction

Every year approximately 200,000 people are admitted to critical care units in the United Kingdom (UK) (ICNARC 2017) many presenting with ongoing weakness, loss of energy, physical impairments, anxiety, depression, post-traumatic stress and other difficulties after hospital discharge (Dowdy et al. 2005; NICE 2009). This group is largely heterogenous; an estimated 58% are over 65’s and 13% over 80’s (Groeger et al. 1993; Bagshaw et al. 2009). However, commonality can be found in their struggle to recover, which can take up to 12 years for some individuals. This journey has a profound impact on the quality of life, healthcare utilisation and economic productivity of individuals (Dowdy et al. 2005; Mhyren et al. 2010; Lone et al. 2018). Exercise-based interventions are well evidenced to increase physical activity levels in other chronic disease populations, with studies in critical care populations showing some promise (McWilliams et al. 2009; Jones et al. 2015; McWilliams et al. 2016). Current guidelines for critical care rehabilitation following discharge from hospital (CG83) recommends patients with rehabilitation needs are reviewed 2–3 months after discharge from critical care including functional assessment (NICE 2009). However, research shows that few hospitals meet this requirement, most of whom offer follow up in a clinic format (Connolly 2014). This service evaluation explored the experiences of patients who have completed a novel outpatient exercise class following critical illness and analysed outcome measures to consider how physical and psychological measures of health were impacted after participation. A behaviour change model (Cane et al. 2012) was used to contextualise findings within the scope of a complex intervention and guide recommendations for improving the current service.

Research questions

• What are the main concerns and challenges faced by critical care survivors after hospital discharge?
• What are patients’ experiences of an exercise intervention and how does this impact their recovery?
• Do exercise capacity, quality of life, anxiety and depression measures change before and after attending the intervention?

Methods

Setting

An outpatient exercise-based group class runs once a week in a District General Therapy department for the benefit of people who have overcome critical illness. The class includes strengthening, balance, and cardiovascular exercises designed to improve the physical function of participants. It is structured in a circuit format and includes 40 minutes of activity followed by a 20 minute education session. The education component includes topics from the multidisciplinary team aimed at informing participants of challenges often faced when recovering from critical illness. These include chronic pain, weakness, fatigue, psychological stress and the use of exercise, diet, and wider support structures in coping with these challenges. A physiotherapist and rehabilitation assistant facilitate the delivery of the class which is run over 6 weeks. No formal training is provided for group facilitators and no formal facilitation style is stipulated. Individuals are identified by a specialist critical care nurse once discharged from the intensive care unit and then followed up via telephone to confirm their attendance for an initial assessment. The initial assessment includes completion of outcome measures and screening for suitability for the class. These measures are then repeated upon completion of the class after 6 weeks.

Design

This service evaluation used a mixed-method design to capture the complex nature of this population. Outcome measures were paired with interview data to elaborate on the quantitative findings and give insight to the mechanisms of participation in the intervention. A grounded theory approach was used for the design of the qualitative arm of the evaluation with a realist epistemological perspective (Lomborg & Kirkevold 2003). The University of East Anglia Health Sciences Department supported the conduct of the project and provided faculty ethics approval (reference 2017/18 98). The reporting of this intervention adheres to the Medical Research Council’s guidance for conducting process evaluations (Moore et al. 2015). NHS research ethics approval was deemed not to be required as this was structured as a service evaluation.

Participants

Participants for the qualitative element were recruited face to face using convenience sampling from a local critical care support group hosted by the national charity, ICU Steps.

These patients had attended and completed the exercise group in the year preceding the evaluation and gave consent to discuss their experiences after meeting the research team.

Inclusion criteria for interviews

• Adults >18 years.
• Previously admitted to critical care.
• Completed the 6-week physical rehabilitation programme between June 2016–2018.

Exclusion criteria

• Any ongoing conflicting treatment.

All participants gave informed consent to take part. Interviews were organised in the participant’s own homes as determined convenient for them.

Data collection procedures

The main method of data collection for this evaluation were the interviews with participants which were conducted using a semi-structured format, audio-recorded and transcribed verbatim. This method of data collection was used to explore the views, experiences, beliefs and motivations of individual participants recovering from critical illness as is supported in current literature (Gill et al. 2008). Author S. Wilson carried out interviews as part of an MSc thesis; and has a clinical background as a physiotherapist with special interest in critical care. A relationship was not established prior to the evaluation commencement; however, patients were familiar with the relevance of the professional role of physiotherapists within critical care. Using a mixed methodology design in this service evaluation shaped the emerging conceptual theory during analysis and informed the structure of interviews to further refine this theory. The researcher was able to question and analyse specific elements of recovery relating to the quantitative outcome measures and explore the context of these areas for participants.

Outcome measures were analysed retrospectively from class records by the author for the two years preceding the evaluation (June 2016–2018). This included basic demographic information and Health related outcome measures detailed below.

Outcome measures

Measures are taken by a physiotherapist at two timepoints; prior to commencing the rehabilitation programme and at the 6th or final session. Outcome measures were chosen to reflect outcomes that are important to patients (Dinglas et al. 2018).

6-minute walk test

The 6-minute walk test (6MWT) is a validated, standardised, self-paced test of exercise capacity (ATS Committee 2002; Brooks et al. 2003) which has previously been used for assessing exercise capacity in the critical care population (McWilliams et al. 2016).

Hospital anxiety and depression questionnaire

The Hospital anxiety and depression (HADS) questionnaire is a widely used, validated (Zigmond & Snaith 1983), appropriate measure for assessing the symptom severity of anxiety disorders and depression in primary care patients and the general population (Bjelland et al. 2002).

Short form 36 questionnaire

The Short form 36 (SF-36) questionnaire classifies quality of life (QOL) and has 36 questions evaluating 8 separate domains:

• Physical functioning.
• Physical role.
• Bodily pain.
• General health.
• Vitality.
• Social functioning.
• Emotional role.
• Mental health.

The responses for each domain are scored and transformed to a 0–100 scale, with higher scores reflecting better QOL (Mahler & Mackowiak 1995).

Analysis

Statistical analysis of outcome measures was conducted using SPSS software. A p-value <0.05 with a 95% confidence interval (CI) was deemed significant.

Interviews were transcribed and analysed using a Grounded theory methodology, which involves coding and comparing transcripts for similarities and concepts (Glaser 1996). The researcher compared transcripts of interviews organising excerpts into codes. These were then reanalysed and compared to reveal an overarching main concern. Results were interpreted using a framework for behaviour change theory (Cane et al. 2012; Michie et al. 2011) which incorporated qualitative and quantitative results to contextualise findings and guide recommendations for promoting engagement with the service.

Using a mixed methodology design in this service evaluation shaped the emerging conceptual theory during analysis and informed the structure of interviews to further refine this theory. The researcher was able to question and analyse specific elements of recovery relating to the quantitative outcome measures and explore the context of these areas for participants. Using this iterative process during analysis gave participants the opportunity to clarify some of the interpretations made by the researcher and add detail to areas not previously considered.

Results

Table 1 shows the demographic information for participants. Data included was limited due to the scope of the service evaluation.

Table 1: Cohort characteristics.

Characteristics	Interviews (n = 8)                              Cohort (n = 25)
Age in years, mean (SD)	73 (11.8)	71.2 (10.2)
Gender (%) Male Female	3 (37.5) 5 (62.5)	14 (56) 11 (44)
Admitting condition (%) Post-operative admission Exacerbation of COPD Respiratory insufficiency Pleural effusion Pulmonary embolism Trauma Not documented	4 (50) 2 (25) 0 (0) 0 (0) 0 (0) 1 (12.5)                      1 (12.5)	6 (24) 4 (16) 4 (16) 2 (8) 1 (4) 0 (0)  8 (32)

Interview data

Following in-depth analysis of interview transcripts, the data revealed a range of challenges faced by participants during recovery from critical illness. By discussing the various elements of these challenges, participants explored the coping mechanisms they used to navigate their recovery journey. Data showed an identification with losing independence during recovery as a main concern, which was multifaceted and included various physical, psychological and social aspects. Parry et al. (2017) suggested that behaviour change research models may help identify solutions which can be used to increase physical activity levels in critical care survivors. They discussed the use of the Behaviour Change Wheel COM-B Model in this population and felt this framework could be helpful in identifying specific strategies to solidify behaviour change based on individual barriers to engagement. For this evaluation, generated themes were mapped onto the COM-B model, illustrated in Table 2, to highlight the key discussion points and guide recommendations for service improvement. No participants withdrew from this phase of the evaluation.

Table 2: Interview results mapped to BCW COM-B Model.

COM-B component	Sub-themes	Quotes
Capability: Physical restrictions	Fatigue	‘I still do get very tired at times’ ‘I did sleep an awful lot’ 507. ‘I wanted to do some housework, and I did one room and I was shattered, and I thought I’d be able to do more’ 506.
	Weakness	‘I became very handicapped with the fact that I was weak’ 501
	Frustration	‘Sometimes I get very frustrated, because I can’t get on my feet’ (502).
	Impact on confidence	‘I’m so very nervous about slipping over’ (503). ‘Previously I could get in the car and drive wherever I want to be, I could get in the car and go. Now I can’t’ (505).
Opportunity: Accessibility	Practicalities	‘If they’d been around the corner we might’ve gone, but they’re a fair way away’ (502) pp. 8.
	Social isolation	‘I did feel a bit on my own in the end’ ‘I stay at home, these are my four walls’ (504).
	Support structures	‘It was causing my husband a bit of hassle to get there so I just decided not to do it anymore’ (504). ‘To get there you need to be taken’ (505).
Motivation: Peer support	Group cohesion	‘It’s having the people that are in the class as well that help you’ (504). ‘With the company, it’s easier and nicer because you have people to talk to. Sometimes when you’re doing the exercises, you can do a bit more’ (506).
	Milestones	‘They couldn’t sometimes see it, but I said: well last week you couldn’t walk across that side, you only did half. They couldn’t remember that, and they were quite surprised’ (506).

Capability

Participants identified challenges with managing weakness and fatigue with daily functional tasks such as cooking, washing, dressing and walking. Participants described how simple tasks would need careful planning and regular breaks to complete.

‘I wanted to do some housework, and I did one room and I was shattered, and I thought I’d be able to do more’ (506).

‘I couldn’t get up the stairs, so I slept downstairs. I couldn’t lift a kettle up or make cups of tea. I couldn’t do the normal things that everybody does like hoover or clean. I couldn’t even wash myself properly. It was down to my husband to do that. My husband took over all the chores really. I still struggle with things now. Like the hoovering. I do it, but it’s not as good as I used to be able to do it’ (504).

Individuals found the class helpful in improving some of their daily tasks and described a sense of achievement with making progress, however small.

‘I must admit when I started (the class) it was exhausting. I’d come home and I’d have a lie down for an hour. Of course, as I grew stronger, I was out with the dog, and I gained the strength. Setting off, yeah, it was difficult, but I was determined to do it, you know. And it was, good, I enjoyed it’ (501).

Participants found the programme useful for regaining functional ability. They described the physical benefit of the sessions but also revealed how weakness and fatigue could act as barriers to participation.

Opportunity

Qualitative data revealed some of the challenges faced by participants gaining access to the rehabilitation programme; the main concerns being related to practicalities, such as parking, transport and personal expense. 1 participant described his worry at paying the bills and felt he could not continue with rehabilitation due to the expense of travelling there:

‘To get to (the hospital) is a 30-mile round trip’ ‘There’s other things I need to pay for’ ‘Everything goes up; gas, electricity, telephone’ (503).

These factors describe the environmental context and resources available to the individual, which reflects the physical construct of the opportunity aspect of the COM-B model (Cane et al. 2012).

Motivation

Participants in this evaluation explained how the group structure of the programme enhanced their drive to regain function, and how they were able to act as a motivator for others. Participants described how patients in the group shared their experiences and how this facilitated a cohesion within the class.

‘Some people told us their story, how ill they were, and you do encourage each other’ (506).

‘When I first went, I was in a wheelchair, and I was exhausted, you know. I thought, “Oh I’m never going to do that”. And there was a lady there, (she) came over to me and she said, “Oh I was just like you” I said, but you are probably a lot younger than me. She said: “Well I don’t know how old you are but I’m 80 next year”. And I said, what! She really gave me confidence because she was 80 and she was really so good. And I thought, blimey, if she can do that at 80, I can. She gave me confidence to move on when I saw what she could do.’ (501)

By facilitating an open, supportive environment, participants could relate to each-other’s experiences. There was a sense of group cohesion and encouragement from staff and other patients, which facilitated participants’ own motivation to progress.

Rehabilitation class data

Within the hospital between June 2016–June 2018, 787 adult patients survived critical illness with a survival rate of 82%. Of the patients who survived, 55 patients (7%) were referred for rehabilitation and 25 subsequently attended an initial assessment and were included in this dataset. 16 patients completed the full 6-week course and submitted complete data for at least one outcome measure.

Table 3 shows descriptive statistics for outcome measures before and after the rehabilitation programme. Short form 36 and HADS outcomes had 13 complete sets of data, and the 6MWT had 8 complete sets of data.

Table 3: Descriptive statistics.

	N	Pre-hoc	Post-hoc
Short form 36, mean (SD) Physical functioning Physical health Emotional stresses Energy Emotional wellbeing Social functioning Pain levels General health	13 13 13 13 13 13 13 13	37.4 (27.2) 19.2 (38.4) 46.2 (51.9) 46.8 (22.3) 71.7 (19.1) 53.8 (31.6) 66.2 (31.1) 56.2 (25.6)	53.5 (23.8) 32.7 (38.7) 53.8 (48.2) 69.2 (20.6) 80.0 (16.7) 72.1 (24.0)  75.2 (29.8) 64.6 (20.3)
6-minute walk distance (m), mean (SD)		228.5 (161.5)	406.2 (162.4)
Hospital anxiety and depression scale Anxiety Depression	13 13	6.8 (4.7) 5.8 (4.3)	4.2 (2.8) 3.9 (3.9)

Table 4 shows the results of statistical analysis using the Wilcoxon non-parametric test for differences between groups. The unadjusted p-values, mean differences, and 95% confidence intervals are included in the table. This is to test whether there was a significant difference between the measures taken before the rehabilitation programme, compared to afterwards.

The 6-minute walk test scores increased by 177.8m on average following the rehabilitation programme compared to before (CI 121.8, 233.7). This difference was statistically significant (p = 0.012) and is more than the minimally clinically important increase of 54–80m.

Table 4: Paired outcomes pre- and post rehabilitation.

	n	Mean difference (SD)	95% CI	p-value
Short form 36
Physical functioning	13	16.1 (22.6)	2.5, 29.7	0.026
Physical health	13	13.5 (19.4)	1.7, 25.2	0.038
Emotional stresses	13	7.7 (45.5)	-19.8, 35.2	0.581
Vitality	13	22.5 (20.1)	10.3, 34.6	0.003
Emotional wellbeing	13	8.3 (10.9)	1.7, 14.9	0.021
Social functioning	13	18.3 (30.5)	-0.1, 36.7	0.07
Pain levels	13	9.0 (15.4)	-0.3, 18.3	0.063
General health	13	8.5 (13.9)	0.1, 16.8	0.046
6-minute walk test (m)	8	177.8 (66.9)	121.8, 233.7	0.012
Hospital anxiety and depression scale
Anxiety	13	2.6 (3.9)	0.3, 5.0	0.035
Depression	13	1.9 (3.0)	0.1, 3.7	0.021

Discussion

Significant improvements in the Hospital anxiety and depression scale were seen following rehabilitation compared to before. Likewise, components of the Short form 36 also improved significantly, including physical health, physical functioning, vitality, emotional wellbeing, and general health.

The evaluation was designed with the aim of identifying components of current practice that require attention to improve the user experience and to better meet the complex needs of this population. Significant improvements were seen in all outcome measures analysed however the clinical relevance of these findings was limited by the small sample size and low adherence to the programme. Qualitative interviews provided insight into the barriers and facilitating factors affecting participation and highlighted the complex needs of this population during recovery.

The benefits of physical activity in regaining physical function are well supported by evidence in other clinical areas but remain limited in the critical care population (Connolly et al. 2015). The difficulties with physical function and capability described by participants was substantiated by current evidence, with a systematic review by Parry et al. (2017) emphasising concerns regarding participants’ physical capability to perform daily tasks. Significant improvements in outcome measures from this evaluation may well be attributable to the normal recovery trajectory of this population, however, this continues to highlight the challenges faced by this population. As suggested by current evidence, clinicians need to consider how physical restrictions may impact capability to participate in physical rehabilitation and adjust activities accordingly (Cane et al. 2012). The evidence gathered for this service evaluation supported the role of a rehabilitation programme in recovering independent function and meeting NICE recommendations. Evidence for enhanced physical rehabilitation in this population remains conflicting (Taito et al. 2019) and there is further need for studies to confirm the efficacy of physical rehabilitation interventions for this population. The literature available to guide clinical practice remains insufficient; this evaluation hopes to guide local changes in this service and inform future studies in this population.

Accessing the programme was identified as a main barrier to participation in the programme. Extensive research has been done regarding the impact of socioeconomic factors on individuals engaging with physical activity programmes in the community (Lindström & Rosvall 2018; Salvo et al. 2018). These concerns combined with the poor uptake to the programme highlight the need to review recruitment strategies to better engage patients and families in physical rehabilitation. Future improvements to the service need to consider the barriers to engagement with rehabilitation and determine how best to address this using evidenced behaviour change theory.

Motivation has been defined in the context of behaviour change theory as all the brain processes that energise and direct behaviour; these can be automatic or reflective (Michie et al. 2011b). Participants in this evaluation identified barriers to motivation during their recovery period, including challenges with their self-esteem, confidence, identity, and emotions. Well evidenced behaviour change concepts such as goal setting may be applicable in this regard, as evidenced by previous research in this population (Corner et al. 2019). Losing independence was difficult to quantify emotionally, with participants describing an extensive mix of feelings which were often difficult to manage. Agard et al. (2012) found that training, perseverance, and continued hope for recovery were the vehicles that moved the process of struggling for independence forward for critical care survivors. This was echoed in the experiences of participants in this evaluation who felt that the service provided an environment conducive to meeting realistic milestones by means of physical activity in the form of exercise training. It has been suggested that recovery in other disease processes can be facilitated by peer support (Davis et al. 2014; Mikkelsen et al. 2016), which could apply to some of the dynamics described by participants in this evaluation. Cane et al. (2012) outlines how a group setting can enhance motivation by developing an individual’s social role and identity as part of that group. The sense of empathy from fellow patients resonated with participants in this evaluation and supports the argument for group-based interventions in this population.

Limitations

As previously discussed, the findings of this evaluation are limited by several important factors. The samples in both the qualitative and quantitative elements are limited in both size and diversity and therefore may not reflect the experiences of the wider population. The inclusion of individuals who had either not completed or chosen not to take part in the programme may have provided valuable insight regarding barriers to participation and provided a balanced perspective to inform recommendations. It is acknowledged that this evaluation is designed to impact change locally, and therefore any wider conclusions must be drawn with caution.

This evaluation used a retrospective before and after design for the quantitative element of the project. It is therefore impossible to make any inferences about the impact of this intervention or make comparisons with the natural recovery trajectory of this population. In addition to this the evaluation method could have been better focused on a single element as opposed to dividing resources between qualitative and quantitative elements. Furthermore, there was variation in quantitative data collection in terms of outcome measure administration and incomplete measures due to changes in staffing over time. This then finally leads to questionable rigour of the data collected and the relevance to wider clinical practice. It is acknowledged that this evaluation is designed to impact change locally, and therefore any wider conclusions must be drawn with caution.

Conclusions

The long-term effects of critical illness were far-reaching and life-changing for participants. From this evaluation it is clear this is a population which faces a range of challenges on their road to recovery, showing great resilience and perseverance to continue improving. The main concern for participants in this evaluation emerged as their loss of independence, which was multifaceted and posed a range of physical, social, and psychological challenges. The interviewees’ perceptions echoed existing research while offering novel insight into the complex challenges faced by this population. This work explores how these challenges impacted their capability, opportunity, and motivation to engage with the intervention. The service was found to help improve physical function and vitality, enhancing the motivation of participants by means of group cohesion and peer support, although findings should be interpreted with caution due to limitations. Behaviour change theory may be helpful in guiding recommendations and implementing changes to the service to respond to the complex needs of this population.

The findings of this evaluation will inform local changes and engage stakeholders to target engagement strategies to mitigate barriers to participation. Future research needs to consider the complex and multifaceted nature of recovery for this population while using participant samples that better reflect the demographic of this group. Current guidelines do not specify how best to support this population, highlighting the need to continue engaging patients and families in future research and intervention development.

Key points

• Participants struggled for independence and described challenges with physical, psychological, and social functioning.
• It was difficult to engage with the outside world after discharge from hospital and participants described feelings of isolation and poor self-confidence.
• An outpatient exercise class may improve physical function, anxiety, depression, and health-related quality of life in people recovering from critical illness.

Acknowledgements

The author would like to thank the participants who volunteered their time to take part in this evaluation. Also, the NIHR (National Institute for Health Research) and UEA (University of East Anglia) for providing the resources and opportunities to complete this project. Thanks to Dr Jane Cross who provided a balance of clinical and academic support to guide me through the many phases to reach completion. Additionally, thanks to West Suffolk NHS Foundation Trust, UK, specifically the therapy department, critical care department, and the Embedded Librarian Service.

Contributors

Suzahn Wilson is first author. Jane Cross is senior author. Helen Else contributed significantly to the study design and writing or revision of the manuscript. All authors contributed to the revision of the manuscripts and approved the final manuscript for submission.

Funding

This project was funded by the National Institute for Health Research/HEE (Health Education England) Integrated Clinical Academic Programme.

Competing interests: None declared.

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