Course of recovery of respiratory muscle strength and exercise capacity in patients discharged home after mechanical ventilation and critical illness - an observational study

Patients who have been admitted to an intensive care unit (ICU) and have
received mechanical ventilation, are prone to long-term physical impairments.
Physical impairments described in literature are limb and respiratory muscle
weakness, fatigue, decreased aerobic capacity, joint pain and neuropathies
(Ohtake et al 2018, Herridge et al 2011, Stevens, Gosselink).
As more and more patients survive critical illness and ICU-stay, as a result of
improvement in medical interventions, there is a larger group of patients
leaving the hospital in need of aftercare in the form of rehabilitation
interventions (Elliot et al 2014, Hodgson et al 2017, Iwashyna and Netzer
2012). For the physical problems as described above, the physiotherapist is
often consulted (Van der Schaaf et al, 2009). Currently there is no scientific
evidence on the best physical therapy interventions, although an international
consensus statement was published in 2016 proposing physical therapy
interventions and a core outcome set for clinical practice (Major et al 2016).
In a project started in June 2018 and funded by SIA-RAAK ('REhabilitation after
Critical Illness and Hospital discharge - REACH) a rehabilitation intervention
for patients who survived critical illness and are discharged home, is
developed in a Community of Practice (CoP). The CoP consists of rehabilitation
professionals from several hospitals in Amsterdam and environment (OLVG
Oost/West, Amsterdam UMC locations AMC and VUMC, Bovenij Hospital, Amstelland
Hospital in Amstelveen and Spaarne Hospital in Hoofddorp) and first line
practitioners from the field of physiotherapy, occupational therapy and
dietetics working in the greater Amsterdam area. The implementation of the
jointly developed intervention for patients after critical illness and hospital
discharge will start in March 2019 and hospitals will start referring patients
to professionals within the REACH network. This feasibility of the intervention
will be evaluated through a research project for which the METC provided a
waiver in July 2018 (W18_237 # 18.282).
Ongoing studies show that during recovery after critical illness not only the
upper and lower limb muscles remain weakened, but also the respiratory muscles.
Mainly the diaphragm is affected, but also the accessory respiratory muscles
and the expiratory muscles weaken (Jonkman et al 2017). At the moment it is
unclear what the influence of these weakened respiratory muscles is on the
physical recovery of the patient. Currently, no additional interventions are
proposed for training of the respiratory muscles, other than generalized
exercise therapy. We hypothesize that the influence of weakened respiratory
muscles on physical functioning and recovery is larger, than is currently
understood and that respiratory muscle weakness might be present for a
prolonged period of time after hospital discharge, in the post-ICU population.

The aim of our study is to establish the long-term course of (recovery of)
respiratory muscle strength and exercise capacity in patients who have received
* 48 hours of mechanical ventilation and are discharged home.

An observational study

Participants will be visited at home, at 3 time points in a six month period
after hospital discharge: week 1, week 12 and week 24. During the home visit 2
physical measurements will be taken, added onto the REACH study for which a
waiver was provided. No intervention will be conducted.
There are no risks associated with participation, however the physical tests
might cause some fatigue as respiratory muscle strength and exercise capacity
are tested. Safety criteria are set up for each of the physical tests. A
risk-benefit analysis was conducted ('Risk assessment in clinical research
projects 16jan2015', AMC CRU document) and the project is determined to be of
negligible risk.