ICU-Acquired Weakness

Critical Care Cycling to Improve Lower Extremity Strength (CYCLE): protocol for an international, multicentre randomised clinical trial of early in-bed cycling for mechanically ventilated patients

INTRODUCTION

In-bed leg cycling with critically ill patients is a promising intervention aimed at minimising immobility, thus improving physical function following intensive care unit (ICU) discharge. We previously completed a pilot randomised controlled trial (RCT) which supported the feasibility of a large RCT. In this report, we describe the protocol for an international, multicentre RCT to determine the effectiveness of early in-bed cycling versus routine physiotherapy (PT) in critically ill, mechanically ventilated adults.

METHODS AND ANALYSIS

We report a parallel group RCT of 360 patients in 17 medical-surgical ICUs and three countries. We include adults (≥18 years old), who could ambulate independently before their critical illness (with or without a gait aid), ≤4 days of invasive mechanical ventilation and ≤7 days ICU length of stay, and an expected additional 2-day ICU stay, and who do not fulfil any of the exclusion criteria. After obtaining informed consent, patients are randomised using a web-based, centralised system to either 30 min of in-bed cycling in addition to routine PT, 5 days per week, up to 28 days maximum, or routine PT alone. The primary outcome is the Physical Function ICU Test-scored (PFIT-s) at 3 days post-ICU discharge measured by assessors blinded to treatment allocation. Participants, ICU clinicians and research coordinators are not blinded to group assignment. Our sample size estimate was based on the identification of a 1-point mean difference in PFIT-s between groups.

ETHICS AND DISSEMINATION

Critical Care Cycling to improve Lower Extremity (CYCLE) is approved by the Research Ethics Boards of all participating centres and Clinical Trials Ontario (Project 1345). We will disseminate trial results through publications and conference presentations.

TRIAL REGISTRATION NUMBER

NCT03471247 (Full RCT); NCT02377830 (CYCLE Vanguard 46 patient internal pilot).

Chronic pain in critical care survivors: a narrative review

Chronic pain is an important problem after critical care admission. Estimates of the prevalence of chronic pain in the year after discharge range from 14% to 77% depending on the type of cohort, the tool used to measure pain, and the time point when pain was assessed. The majority of data available come from studies using health-related quality of life tools, although some have included pain-specific tools. Nociceptive, neuropathic, and nociplastic pain can occur in critical care survivors, but limited information about the aetiology, body site, and temporal trajectory of pain is currently available. Older age, pre-existing pain, and medical co-morbidity have been associated with pain after critical care admission. No trials were identified of interventions to target chronic pain in survivors specifically. Larger studies, using pain-specific tools, over an extended follow-up period are required to confirm the prevalence, identify risk factors, explore any association between acute and chronic pain in this setting, determine the underlying pathological mechanisms, and inform the development of future analgesic interventions.

Sepsis induced denervation-like changes at the neuromuscular junction

BACKGROUND

The aim of this study was to determine the functional and biochemical changes at the neuromuscular junction (NMJ) induced by sepsis.

MATERIALS AND METHODS

Male Sprague-Dawley rats were divided into three groups as follows: control, denervation, and sepsis. The rats were subjected to cecal ligation and puncture (CLP) or tibias nerve transection. NMJ function and the area of end plates were assessed, and the protein level of acetylcholine receptors and axonal neuregulin-1 was evaluated on postoperative days 1, 7, and 14.

RESULTS

In the control group, the amplitude of compound muscle action potential (CMAP) was 16.51 ± 2.53 mV. In the sepsis group, the amplitude of CMAP decreased, and duration was prolonged on postoperative days 7 and 14 (P < 0.01). Meanwhile, motor conduction velocity decreased significantly (P < 0.01). CMAP was lost in the denervation group. The twitch tension magnitude gradually declined (P < 0.05) in the sepsis group, although it could not be recorded after lesion. Sepsis and denervation upregulated the expression of γ-nicotinic acetylcholine receptor (nAChR) and α7-nAChR in muscle membrane, compared with those in normal NMJ (261.4 ± 26.5 μm(2)). The NMJ area decreased from 254.6 ± 23.8 μm(2) (1 d after CLP) to 275.4 ± 22.6 μm(2) (7 d after CLP) to 322.7 ± 34.4 μm(2) (14 d after CLP). The postsynaptic NMJ had more discrete fragments (3.84 ± 0.6) compared with the control group (2.13 ± 0.4; P < 0.01). After denervation, NMJ underwent fragmentation and the number of discrete fragments increased (5.57 ± 1.2; P < 0.01). NMJ area increased from 254.6 ± 23.8 μm(2) (1 d after CLP) to 275.4 ± 22.6 μm(2) (7 d after CLP) to 322.7 ± 34.4 μm(2) (14 d after CLP). Sepsis induced neuregulin-1 to decrease from 1 d up to 2 wk compared with the control group (P < 0.05).

CONCLUSIONS

Chronic sepsis has a denervation-like effect on the NMJ, which was indicated by upregulation of heterogeneous nAChRs, the increased area of end plates, and demyelination of the motoneuron axon.

ICU early mobilization: from recommendation to implementation at three medical centers

OBJECTIVE

To compare and contrast the process used to implement an early mobility program in ICUs at three different medical centers and to assess their impact on clinical outcomes in critically ill patients.

DESIGN

Three ICU early mobilization quality improvement projects are summarized utilizing the Institute for Healthcare Improvement framework of Plan-Do-Study-Act.

INTERVENTION

Each of the three ICU early mobilization programs required an interprofessional team-based approach to plan, educate, and implement the ICU early mobility program. Champions from each profession-nursing, physical therapy, physician, and respiratory care-were identified to facilitate changes in ICU culture and clinical practice and to identify and address barriers to early mobility program implementation at each institution.

SETTING

The medical ICU at Wake Forest University, the medical ICU at Johns Hopkins Hospital, and the mixed medical-surgical ICU at the University of California San Francisco Medical Center.

RESULTS

Establishing an ICU early mobilization quality improvement program resulted in a reduced ICU and hospital length of stay at all three institutions and decreased rates of delirium and the need for sedation for the patients enrolled in the Johns Hopkins ICU early mobility program.

CONCLUSION

Instituting a planned, structured ICU early mobility quality improvement project can result in improved outcomes and reduced costs for ICU patients across healthcare systems.

Small nerve fiber pathology in critical illness

BACKGROUND

Degeneration of intraepidermal nerve fibers (IENF) is a hallmark of small fiber neuropathy of different etiology, whose clinical picture is dominated by neuropathic pain. It is unknown if critical illness can affect IENF.

METHODS

We enrolled 14 adult neurocritical care patients with prolonged intensive care unit (ICU) stay and artificial ventilation (≥ 3 days), and no previous history or risk factors for neuromuscular disease. All patients underwent neurological examination including evaluation of consciousness, sensory functions, muscle strength, nerve conduction study and needle electromyography, autonomic dysfunction using the finger wrinkling test, and skin biopsy for quantification of IENF and sweat gland innervation density during ICU stay and at follow-up visit. Development of infection, sepsis and multiple organ failure was recorded throughout the ICU stay.

RESULTS

Of the 14 patients recruited, 13 (93%) had infections, sepsis or multiple organ failure. All had severe and non-length dependent loss of IENF. Sweat gland innervation was reduced in all except one patient. Of the 7 patients available for follow-up visit, three complained of diffuse sensory loss and burning pain, and another three showed clinical dysautonomia.

CONCLUSIONS

Small fiber pathology can develop in the acute phase of critical illness and may explain chronic sensory impairment and pain in neurocritical care survivors. Its impact on long term disability warrants further studies involving also non-neurologic critical care patients.

Exercise rehabilitation for patients with critical illness: a randomized controlled trial with 12 months of follow-up

INTRODUCTION

The purpose of this trial was to investigate the effectiveness of an exercise rehabilitation program commencing during ICU admission and continuing into the outpatient setting compared with usual care on physical function and health-related quality of life in ICU survivors.

METHODS

We conducted a single-center, assessor-blinded, randomized controlled trial. One hundred and fifty participants were stratified and randomized to receive usual care or intervention if they were in the ICU for 5 days or more and had no permanent neurological insult. The intervention group received intensive exercises in the ICU and the ward and as outpatients. Participants were assessed at recruitment, ICU admission, hospital discharge and at 3-, 6- and 12-month follow-up. Physical function was evaluated using the Six-Minute Walk Test (6MWT) (primary outcome), the Timed Up and Go Test and the Physical Function in ICU Test. Patient-reported outcomes were measured using the Short Form 36 Health Survey, version 2 (SF-36v2) and Assessment of Quality of Life (AQoL) Instrument. Data were analyzed using mixed models.

RESULTS

The a priori enrollment goal was not reached. There were no between-group differences in demographic and hospital data, including acuity and length of acute hospital stay (LOS) (Acute Physiology and Chronic Health Evaluation II score: 21 vs 19; hospital LOS: 20 vs 24 days). No significant differences were found for the primary outcome of 6MWT or any other outcomes at 12 months after ICU discharge. However, exploratory analyses showed the rate of change over time and mean between-group differences in 6MWT from first assessment were greater in the intervention group.

CONCLUSIONS

Further research examining the trajectory of improvement with rehabilitation is warranted in this population.

TRIAL REGISTRATION

The trial was registered with the Australian New Zealand Clinical Trials Registry ACTRN12605000776606.

Strategies for post ICU rehabilitation

PURPOSE OF REVIEW

As numbers of patients who survive a critical illness increase, often within a context of comorbidities and acquired physical, mental or cognitive sequelae [postintensive care syndrome (PICS)], identifying effective recovery and rehabilitation strategies is paramount. In this review, we discuss recent studies that inform our developing understanding for improving the recovery trajectory for survivors of a critical illness during the postintensive care and posthospital periods.

RECENT FINDINGS

New studies, although at this stage often presented as pilot work, provide important beginning messages for improving recovery from a critical illness. Some pilot studies demonstrate promise of effective interventions, whereas other studies offer useful baseline information for improving the power of tested interventions.

SUMMARY

Innovative rehabilitation and recovery strategies during the postintensive care and posthospital periods are now being published. Further research with larger sample sizes, well-documented usual care and intervention arms and in different critical illness cohorts is required to demonstrate the optimal approaches for screening, implementation, outcome assessment and follow-up periods for rehabilitation interventions in the postintensive care phase of a patient's recovery.

Active rehabilitation during extracorporeal membrane oxygenation as a bridge to lung transplantation

BACKGROUND

Patients with end-stage lung disease often progress to critical illness, which dramatically reduces their chance of survival following lung transplantation. Pre-transplant deconditioning has a significant impact on outcomes for all lung transplant patients, and is likely a major contributor to increased mortality in critically ill lung transplant recipients. The aim of this report is to describe a series of patients bridged to lung transplant with extracorporeal membrane oxygenation (ECMO) and to examine the potential impact of active rehabilitation and ambulation during pre-transplant ECMO.

METHODS

This retrospective case series reviews all patients bridged to lung transplantation with ECMO at a single tertiary care lung transplant center. Pre-transplant ECMO patients receiving active rehabilitation and ambulation were compared to those patients who were bridged with ECMO but did not receive pre-transplant rehabilitation.

RESULTS

Nine consecutive subjects between April 2007 and May 2012 were identified for inclusion. One-year survival for all subjects was 100%, with one subject alive at 4 months post-transplant. The 5 subjects participating in pre-transplant rehabilitation had shorter mean post-transplant mechanical ventilation (4 d vs 34 d, P = .01), ICU stay (11 d vs 45 d, P = .01), and hospital stay (26 d vs 80 d, P = .01). No subject who participated in active rehabilitation had post-transplant myopathy, compared to 3 of 4 subjects who did not participate in pre-transplant rehabilitation on ECMO.

CONCLUSIONS

Bridging selected critically ill patients to transplant with ECMO is a viable treatment option, and active participation in physical therapy, including ambulation, may provide a more rapid post-transplantation recovery. This innovative strategy requires further study to fully evaluate potential benefits and risks.

Critical illness polyneuropathy and myopathy: a major cause of muscle weakness and paralysis

Critical illness polyneuropathy (CIP) and myopathy (CIM) are complications of critical illness that present with muscle weakness and failure to wean from the ventilator. In addition to prolonging mechanical ventilation and hospitalisation, CIP and CIM increase hospital mortality in patients who are critically ill and cause chronic disability in survivors of critical illness. Structural changes associated with CIP and CIM include axonal nerve degeneration, muscle myosin loss, and muscle necrosis. Functional changes can cause electrical inexcitability of nerves and muscles with reversible muscle weakness. Microvascular changes and cytopathic hypoxia might disrupt energy supply and use. An acquired sodium channelopathy causing reduced muscle membrane and nerve excitability is a possible unifying mechanism underlying CIP and CIM. The diagnosis of CIP, CIM, or combined CIP and CIM relies on clinical, electrophysiological, and muscle biopsy investigations. Control of hyperglycaemia might reduce the severity of these complications of critical illness, and early rehabilitation in the intensive care unit might improve the functional recovery and independence of patients.