Neuromuscular sequelae of critical illness

Foot drop in critically ill patients: a narrative review of an elusive complication with intricate implications for recovery and rehabilitation

Foot drop is a condition characterized by the inability to lift the foot upwards towards the shin bone. This condition may affect a proportion of critically ill patients, impacting on their recovery after the acute phase of the illness. The occurrence of foot drop in critical care patients may result from various underlying causes, including neurological injuries, muscular dysfunction, nerve compression, or vascular compromise. Understanding the etiology and assessing the severity of foot drop in these patients is essential for implementing appropriate management strategies and ensuring better patient outcomes. In this comprehensive review, we explore the complexities of foot drop in critically ill patients. We search for the potential risk factors that contribute to its development during critical illness, the impact it has on patients' functional abilities, and the various diagnostic techniques adopted to evaluate its severity. Additionally, we discuss current treatment approaches, rehabilitation strategies, and preventive measures to mitigate the adverse effects of foot drop in the critical care setting. Furthermore, we explore the roles of critical care physical therapists, neurologists, and other healthcare professionals in the comprehensive care of patients with foot drop syndrome and in such highlighting the importance of a multidisciplinary approach.

Survey of sensory impairment in critically ill patients after intensive care unit discharge: An ambidirectional cohort study

BACKGROUND

Sensory impairment affects the quality of life after intensive care. However, no studies have comprehensively examined sensory impairment after intensive care.

OBJECTIVES

This study aimed to investigate sensory impairment in critically ill patients.

METHODS

This ambidirectional cohort study was conducted in the intensive care unit (ICU) of a university hospital between April 2017 and January 2020. Patients who survived despite invasive mechanical ventilation for >48 h, with a discharge period of >6 months, participated in the study. A questionnaire was sent to consenting patients to investigate the presence or absence of sensory impairment at that time, and treatment-related data were collected from their medical records.

RESULTS

Of 75 eligible patients, 62 responded to our survey. Twenty-seven (43.6%) patients had some sensory impairment. Nine (14.5%) patients had chronic pain after ICU discharge, 4 (6.5%) had chronic pain and visual impairment, 3 (4.8%) had visual impairment only, and 3 (4.8%) had chronic pain and taste impairment. The most common overlapping symptom was a combination of chronic pain.

CONCLUSIONS

Critically ill patients who survived and were discharged from the ICU accounted for 43.6% of patients with complaints of sensory impairment in the chronic phase. The results of this study suggest the need for follow-up and treatment of possible sensory impairment following ICU discharge.

Illness Weakness, Polyneuropathy and Myopathy: Diagnosis, treatment, and long-term outcomes

BACKGROUND

Severe weakness associated with critical illness (CIW) is common. This narrative review summarizes the latest scientific insights and proposes a guide for clinicians to optimize the diagnosis and management of the CIW during the various stages of the disease from the ICU to the community stage.

MAIN BODY

CIW arises as diffuse, symmetrical weakness after ICU admission, which is an important differentiating factor from other diseases causing non-symmetrical muscle weakness or paralysis. In patients with adequate cognitive function, CIW can be easily diagnosed at the bedside using manual muscle testing, which should be routinely conducted until ICU discharge. In patients with delirium or coma or those with prolonged, severe weakness, specific neurophysiological investigations and, in selected cases, muscle biopsy are recommended. With these exams, CIW can be differentiated into critical illness polyneuropathy or myopathy, which often coexist. On the general ward, CIW is seen in patients with prolonged previous ICU treatment, or in those developing a new sepsis. Respiratory muscle weakness can cause neuromuscular respiratory failure, which needs prompt recognition and rapid treatment to avoid life-threatening situations. Active rehabilitation should be reassessed and tailored to the new patient's condition to reduce the risk of disease progression. CIW is associated with long-term physical, cognitive and mental impairments, which emphasizes the need for a multidisciplinary model of care. Follow-up clinics for patients surviving critical illness may serve this purpose by providing direct clinical support to patients, managing referrals to other specialists and general practitioners, and serving as a platform for research to describe the natural history of post-intensive care syndrome and to identify new therapeutic interventions. This surveillance should include an assessment of the activities of daily living, mood, and functional mobility. Finally, nutritional status should be longitudinally assessed in all ICU survivors and incorporated into a patient-centered nutritional approach guided by a dietician.

CONCLUSIONS

Early ICU mobilization combined with the best evidence-based ICU practices can effectively reduce short-term weakness. Multi-professional collaborations are needed to guarantee a multi-dimensional evaluation and unitary community care programs for survivors of critical illnesses.

[Aftercare of ICU patients: A task for pneumology?]

As the number of patients treated in intensive care medicine increases, so does the number of those who suffer from the long-term consequences of critical illness and the consequences of a stay in an intensive care unit. For this group of patients with a post-intensive care syndrome (PICS), there are currently no specialized outpatient care structures that follow the hospital stay and possible follow-up treatment. A number of studies are researching the effectiveness of intensive care outpatient clinics nationally and internationally.After presenting the PICS and the associated complex need for care, this review article presents various model projects for outpatient follow-up care of critically ill patients. We discuss whether the field of pneumology is particularly suitable for the study of therapy control of complex clinical pictures since it has vast experience in the treatment of intensive care patients and the outpatient care of chronically ill patients.

Single fibre cytoarchitecture in ventilator-induced diaphragm dysfunction (VIDD) assessed by quantitative morphometry second harmonic generation imaging: Positive effects of BGP-15 chaperone co-inducer and VBP-15 dissociative corticosteroid treatment

Ventilator-induced diaphragm dysfunction (VIDD) is a common sequela of intensive care unit (ICU) treatment requiring mechanical ventilation (MV) and neuromuscular blockade (NMBA). It is characterised by diaphragm weakness, prolonged respirator weaning and adverse outcomes. Dissociative glucocorticoids (e.g., vamorolone, VBP-15) and chaperone co-inducers (e.g., BGP-15) previously showed positive effects in an ICU-rat model. In limb muscle critical illness myopathy, preferential myosin loss prevails, while myofibrillar protein post-translational modifications are more dominant in VIDD. It is not known whether the marked decline in specific force (force normalised to cross-sectional area) is a pure consequence of altered contractility signaling or whether diaphragm weakness also has a structural correlate through sterical remodeling of myofibrillar cytoarchitecture, how quickly it develops, and to which extent VBP-15 or BGP-15 may specifically recover myofibrillar geometry. To address these questions, we performed label-free multiphoton Second Harmonic Generation (SHG) imaging followed by quantitative morphometry in single diaphragm muscle fibres from healthy rats subjected to five or 10 days of MV + NMBA to simulate ICU treatment without underlying confounding pathology (like sepsis). Rats received daily treatment of either Prednisolone, VBP-15, BGP-15 or none. Myosin-II SHG signal intensities, fibre diameters (FD) as well as the parameters of myofibrillar angular parallelism (cosine angle sum, CAS) and in-register of adjacent myofibrils (Vernier density, VD) were computed from SHG images. ICU treatment caused a decline in FD at day 10 as well as a significant decline in CAS and VD from day 5. Vamorolone effectively recovered FD at day 10, while BGP-15 was more effective at day 5. BGP-15 was more effective than VBP-15 in recovering CAS at day 10 although not to control levels. In-register VD levels were restored at day 10 by both compounds. Our study is the first to provide quantitative insights into VIDD-related myofibrillar remodeling unravelled by SHG imaging, suggesting that both VBP-15 and BGP-15 can effectively ameliorate the structure-related dysfunction in VIDD.

Sequelae and mortality in patients with HIV/AIDS and Progressive Multifocal Leukoencephalopathy: Systematic review and case series in the Brazilian Amazon

Background

Progressive Multifocal Leukoencephalopathy (PML) is an opportunistic neurological disease that mainly affects individuals with HIV/AIDS and has high morbidity and mortality, due to its demyelinating characteristic. This co-infection has been reported since the begging of HIV/Aids epidemic with increasing unfavorable outcomes, however, factors associated to sequelae and death are greatly unknown. In this study we aimed to understand factors associated with the main outcomes of individuals diagnosed with PML and HIV/AIDS, in addition to reporting the characteristics of patients presenting to a referral center in infectious diseases in the Brazilian Amazon.

Methods

A systematic review was performed until July 2022, following the PRISMA guidelines, at Medline/Pubmed, Web of Science, Lilacs and Scielo databases using combinations of HIV, Aids, JC Virus and Progressive Multifocal Leukoencephalopathy, with no restriction to publication date. Additional cases, meeting the eligibility criteria, were added from our hospital database, which consisted of patients presenting PML/HIV between 2010 and 2022. A meta-analysis aiming to explore factors associated to sequelae and death was performed. Baseline characteristics were described using mean and standard deviation, or median and interquartile range when appropriate; multivariate analysis was performed to study factors associated to death and sequelae outcomes.

Results

Eighteen patients were diagnosed between 2010 and 2022, of these, 10 had positive PCR for JC virus. In the Systematic Review, 216 studies yielded 235 confirmed cases of co-infection. A total of 245 were included for analysis. The rates of death and sequelae were, respectively, 47.1% (114/242) and 41.2% (54/131). The use of antiretroviral therapy was more associated with a lower chance of death (OR 0.30, 95% CI: 0.11-0.83), while muscle weakness (OR 4.82, 95% CI: 2.07-11.21) and muscle spasms (OR 6.12, 95% CI: 1.05-35.76) were associated with greater chances of sequelae.

Conclusion

Those on antiretroviral therapy appear to be less likely to die, and among those who survive, those who have muscle weakness as a symptom on admission are more likely to develop sequelae. Adherence to ART, as well as a comprehensive clinical evaluation and follow-up may help to improve clinical outcomes and awareness of morbidities.

Recovery and long term functional outcome in people with critical illness polyneuropathy and myopathy: a scoping review

BACKGROUND

Intensive care unit acquired weakness (ICUAW), embraces an array of disorders labeled "critical illness polyneuropathy" (CIP), "critical illness myopathy" (CIM) or "critical illness polyneuromyopathy" (CIPNM). Several studies have addressed the various characteristics of ICUAW, but the recovery is still unclear.

OBJECTIVE

The present review investigated the recovery and the long-term functional outcome of subjects with ICUAW, whether the types of ICUAW have different outcomes and whether there is any supporting evidence.

METHODS

Literature search was performed from MEDLINE/PubMed, CINAHL, EMBASE, PeDro, Web of Science and Scopus. Inclusion criteria were: i) sample size including five or more subjects; ii) subjects who suffered from ICUAW and/or CIP, CIM and CIP/CIM; iii) ICUAW ascertained by EMG. Follow-ups longer than one year were defined as long-term.

RESULTS

Twenty-nine studies met the inclusion criteria. In total, 788 subjects with ICUAW were enrolled: 159 (20.1%) died and 588 (74.6%) were followed. Of all the included patients, 613 (77.7%) had CIP, 82 (10.4%) CIM and 56 (7.1%) CIP/CIM. Overall, 70.3% of the subjects with ICUAW fully recovered. Seven (24.1%) studies had a follow-up longer than 1 year (range 2-8) with 173 (21.9%) subjects enrolled globally and 108 followed. Of these subjects, 88.8% gained full recovery. Most of the studies did not use proper functional scales and only 4 and 3 studies employed the Barthel scale and the Functional Independence Measure (FIM) scale. Differentiation between the types of ICUAW was performed in 7 studies, but only 3 studies reported that subjects with CIM had a better prognosis and earlier recovery than subjects with CIP/CIM.

CONCLUSIONS

Subjects with ICUAW could achieve good recovery and could improve at follow-up. However, the quality of the published studies due to short follow-ups and the paucity of defined outcome measures require confirms.

Incidence, Time Course and Influence on Quality of Life of Intensive Care Unit-Acquired Weakness Symptoms in Long-Term Intensive Care Survivors

PURPOSE

Intensive care unit-acquired weakness (ICUAW) can manifest as muscle weakness or neuropathy-like symptoms, with diagnosis remaining a challenge. Uncertainties surround the long-term cause and sequelae. Therefore, the purpose was to assess incidence, time course and long-term influence on quality of life (QoL) of symptoms in ICU survivors.

METHODS

After ethical approval and registration (www.drks.de: DRKS00011593), in a single-center cohort study all patients admitted to the ICU in 2007-2017 in a German university hospital were screened. Out of 1,860 patients (≥7d ICU care including ventilation support for ≥72 h, at least 6mo-10y after ICU) 636 were deceased, 912 survivors were contacted.

RESULTS

149 former patients (age: 63.5 ± 13.1y; males: 73%; duration in ICU: 20.8 ± 15.7d; duration of ventilation: 16.5 ± 13.7 h; time post-ICU: 4.4 ± 2.7y, 5-10y: 43%) consented to be interviewed concerning occurrence, duration, recovery and consequences of ICUAW-associated muscle weakness or neuropathy-like symptoms after ICU. In 75% at least 1 persistent or previous symmetrical symptom was reported (myopathy-like muscle weakness: 43%; neuropathy-like symptoms: 13%; both: 44%) and rated as incidence of ICUAW. However, only 18% of participants had received an ICUAW diagnosis by their physicians, although 62% had persistent symptoms up to 10y after ICU (5-10y: 46%). Only 37% of participants reported a complete recovery of symptoms, significantly associated with an initially low number of symptoms after ICU (p < 0.0001), myopathy-like symptoms (p = 0.024), and younger age at the time of ICU admission (55.7 ± 13.1 vs. 62.6 ± 10.6y, p < 0.001). ICUAW still impaired the QoL at the time of the interview in 74% of affected survivors, with 30% reporting severe impairment.

CONCLUSION

ICUAW symptoms were disturbingly common in the majority of long-term survivors, indicating that symptoms persist up to 10y and frequently impair QoL. However, only a small number of patients had been diagnosed with ICUAW. Trial registry: Deutsches Register Klinischer Studien (DRKS), https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00011593, registration number: DRKS00011593.

Neuromuscular Disorders in the Intensive Care Unit

PURPOSE OF REVIEW

This article discusses the pathophysiology, presentation, diagnosis, treatment, and prognosis of common neuromuscular disorders seen in the intensive care unit, including Guillain-Barré syndrome, myasthenia gravis, and intensive care unit-acquired weakness.

RECENT FINDINGS

Guillain-Barré syndrome can have an excellent prognosis if patients are diagnosed early, appropriately treated, and monitored for complications, including respiratory failure and dysautonomia. Intensive care unit-acquired weakness increases overall mortality in patients who are critically ill, and distinguishing between critical illness myopathy and critical illness polyneuropathy may have important prognostic implications.

SUMMARY

Neuromuscular disorders are not rare in the intensive care unit setting, and precise identification and treatment of these conditions can greatly impact long-term outcomes.

Pathophysiology and management of critical illness polyneuropathy and myopathy

Critical illness-associated weakness (CIAW) is an umbrella term used to describe a group of neuromuscular disorders caused by severe illness. It can be subdivided into three major classifications based on the component of the neuromuscular system (i.e. peripheral nerves or skeletal muscle or both) that are affected. This includes critical illness polyneuropathy (CIP), critical illness myopathy (CIM), and an overlap syndrome, critical illness polyneuromyopathy (CIPNM). It is a common complication observed in people with critical illness requiring intensive care unit (ICU) admission. Given CIAW is found in individuals experiencing grave illness, it can be challenging to study from a practical standpoint. However, over the past 2 decades, many insights into the pathophysiology of this condition have been made. Results from studies in both humans and animal models have found that a profound systemic inflammatory response and factors related to bioenergetic failure as well as microvascular, metabolic, and electrophysiological alterations underlie the development of CIAW. Current management strategies focus on early mobilization, achieving euglycemia, and nutritional optimization. Other interventions lack sufficient evidence, mainly due to a dearth of large trials. The goal of this Physiology in Medicine article is to highlight important aspects of the pathophysiology of these enigmatic conditions. It is hoped that improved understanding of the mechanisms underlying these disorders will lead to further study and new investigations for novel pharmacologic, nutritional, and exercise-based interventions to optimize patient outcomes.

Long-term outcomes after critical illness: recent insights

Intensive care survivors often experience post-intensive care sequelae, which are frequently gathered together under the term “post-intensive care syndrome” (PICS). The consequences of PICS on quality of life, health-related costs and hospital readmissions are real public health problems. In the present Viewpoint, we summarize current knowledge and gaps in our understanding of PICS and approaches to management.

Testosterone improves muscle function of the extensor digitorum longus in rats with sepsis

Among patients with intensive care unit-acquired weakness (ICUAW), skeletal muscle strength often decreases significantly. The present study aimed to explore the effects of testosterone propotionate on skeletal muscle using rat model of sepsis. Male SD rats were randomly divided into experimental group, model control group, sham operation group and blank control group. Rats in experimental group were given testosterone propionate two times a week, 10 mg/kg for 3 weeks. Maximal contraction force, fatigue index and cross-sectional area of the extensor digitorum longus (EDL) were measured. Myosin, IGF-1, p-AKT and p-mTOR levels in EDL were detected by Western blot. Histological changes of the testis and prostate were detected by hematoxylin and eosin staining. We found that maximal contraction force and fatigue index of EDL in experimental group were significantly higher than in model control group. Cross-sectional area of fast MHC muscle fiber of EDL in group was significantly higher than in model control group. The levels of myosin, IGF-1, p-AKT and p-mTOR of EDL in experimental group were significantly higher than in model control group. In addition, no testicle atrophy and prostate hyperplasia were detected in experimental group. In conclusion, these results suggest that testosterone propionate can significantly improve skeletal muscle strength, endurance and volume of septic rats, and the mechanism may be related to the activation of IGF-1/AKT pathway. Moreover, testosterone propionate with short duration does not cause testicular atrophy and prostate hyperplasia in septic rats. Therefore, testosterone propionate is a potential treatment for muscle malfunction in ICUAW patients.

Critical illness polyneuromyopathy: Functional impact after severe acquired brain injuries

OBJECTIVES

Critical illness polyneuropathy and myopathy (CIPNM) frequently affects critical patients and can occur after severe acquired brain injuries (sABI) influencing the functional recovery. We aimed to assess how the concomitance between CIPNM and sABI might influence the rehabilitative outcomes in terms of functional autonomy, oral feeding recovery and endotracheal tube weaning.

MATERIALS AND METHODS

Adult patients with sABI admitted to an intensive rehabilitation unit and underwent an electromyography examination within seven days after admission were included. Assessed rehabilitative outcomes at discharge were decannulation success and its timing, functional autonomy measured by the Functional Independence Measure (FIM) and the Glasgow outcome scale expanded (GOS-E) and oral feeding recovery assessed by the Functional Oral Intake Scale (FOIS) score.

RESULTS

Among the 224 included patients (81 (36%) females, age (median[IQR]): 68.73[21.66] years), 119 (53.1%) presented CIPNM at admission. Albeit the change of rehabilitative outcomes between admission and discharge was significant in all the sABI patients (P < .001 for ΔFOIS, ΔFIM and ΔGOS-E), those with a concomitant CIPNM achieved significantly lower scores as evaluated by Mann-Whitney tests (P < .001 for ΔFIM Δ and GOS-E; P < .005 for ΔFOIS). The CIPNM absence was associated with a higher probability to achieve functional autonomy (GOS-E > 4) (OR:4.57 (1.49/14.06); P < .01) and oral feeding recovery (FOIS ≥ 4) (OR:2.07 (1.07/3.99); P = .03) at discharge. CIPNM presence did not influence decannulation success but a longer time to cannula weaning was required (P < .01 in the log-rank test).

CONCLUSIONS

CIPMN significantly affects the rehabilitative outcomes after a sABI and should be taken into account for better rehabilitative handling.

Nursing perspectives and strategies in patients with respiratory insufficiency

BACKGROUND

Approximately 30% of patients admitted to an intensive care unit experience respiratory distress. The COVID-19 pandemic has led to an enormous increase in patients with respiratory symptoms. Nurse competence is essential for ensuring quality treatment and care for these patients; however, research on nursing strategies for patients with respiratory insufficiency is limited.

AIM

This study explored nurses' perspectives on and nursing strategies in patients with respiratory insufficiency when admitted to three different intensive care units.

DESIGN

The study had an exploratory, descriptive, qualitative design.

METHODS

Four focus group interviews with a total of 20 nurses, critical care nurses, and critical care nursing students were conducted. Data were analysed using content analysis.

RESULTS

Participants' perspectives fell into two main themes: "nurse competence" and "the art of balancing." "Nurse competence" incorporated the sub-themes "observations and assessments," "to make decisions," and "collaboration." The theme 'the art of balancing' incorporated the sub-themes "nursing interventions," "patients feeling safe," and "patient participation."

CONCLUSION

This study contributes new knowledge about nurses' perspectives on patients with respiratory insufficiency. Nurse competence was assumed essential to observe, assess, and treat patients with respiratory insufficiency. Nursing strategies included balancing nursing interventions, conducting medical treatment, and taking a whole-person approach to patients' needs.

RELEVANCE TO CLINICAL PRACTICE

The COVID-19 pandemic has shown the need for nurse competence in caring for patients with respiratory insufficiency. This study adds to existing literature emphasizing the need for competence in health care services. Caring for patients with respiratory insufficiency requires nurses with experience; competence in observation, assessment, and medical treatment; and a whole-person approach to patients' needs.

Approach to critical illness myopathy and polyneuropathy in the older SARS-CoV-2 patients

One of the major concerns of the health care community and the public surrounding the SARS-CoV-2 pandemic is the availability and use of ventilators. Unprecedented surges of patients presented to intensive care units across the country, with older adults making up a large proportion of the patient population. This paper illustrates contemporary approaches to critical illness myopathy (CIM), critical illness polyneuropathy (CIP), and critical illness polyneuromyopathy (CIPNM) in older patients, including incidence, risk factors, mechanisms for pathology, diagnosis, contemporary treatment approaches, and outcomes. We hope that the following analysis may help educate clinicians and ultimately decrease the duration of the mechanical ventilation required by these patients, resulting in improved clinical outcomes and an increase in ventilator availability for other patients in need.

Intensive care unit acquired weakness: A protocol for an overview of systematic reviews and meta-analysis

BACKGROUND

Intensive care unit-acquired weakness (ICU-AW) is an acquired neuromuscular lesion and a common occurrence in patients who are critically ill. There are already systematic reviews on ICU-AW. Therefore, we provide a protocol for an overview of systematic reviews to improve the effectiveness of the construction of an evidence-based practice for prevention of ICU-AW.

METHODS

We will search the PubMed, CINAHL, EMBASE, and the Cochrane Library for the relevant systematic review or meta-analyses about ICU-AW. Study selection, data extraction, and the quality assessment of the included studies will be performed independently by 2 reviewers. And the methodological quality, report quality and evidence quality will be evaluated by Assessment of Multiple Systematic Reviews-2 tool, Preferred Reporting Items for Systematic Reviews and Meta Analyses Statement checklist and Grading of Recommendations Assessment, Development and Evaluation system, respectively.

RESULTS

This overview of systematic reviews and meta-analysis will collect the evidence published about the ICU-AW.

CONCLUSION

We hope that our research will contribute to clinicians and public decision making about the ICU-AW.

REGISTRATION NUMBER

INPLASY202070067.

Outcome of improved care bundle in acute respiratory failure patients

BACKGROUND

Prolonged physical immobilization has negative effects on patients on mechanical ventilation (MV).

AIMS

To introduce a quality improvement programme with early mobilization on the outcomes of patients on MV in the intensive care unit (ICU). We particularly studied the impact of the ABCDE (daily Awakening, Breathing trial, drug Co-ordination, Delirium survey and treatment, and Early mobilization) bundle on the outcome of MV patients with acute respiratory failure in the ICU.

DESIGN

This is a retrospective, observational, before-and-after outcome study.

METHOD

Adult patients on MV (N = 173) admitted to a medical centre ICU with 19 beds in southern Taiwan were enrolled. A multidisciplinary team (critical care nurse, nursing assistant, respiratory therapist, physical therapist, patient's family) performed ABCDE with early mobilization within 72 hours of MV when patients became haemodynamically stable (twice daily [30 minutes each time], 5 days/week during family visits and in co-operation with family members).

MAIN OUTCOME MEASURES

The main outcome measures were differences of MV duration, ICU and hospital length of stay, medical costs, and intra-hospital mortality before (phase 1) and after (phase 2) bundle care.

RESULTS

Phases 1 and 2 revealed several differences, including Acute Physiology and Chronic Health Evaluation (APACHE) II and blood urea nitrogen and creatinine levels. The patients in phase 2 had a significantly lower mean ICU length of stay (8.0 vs 12.0 days) but a similar MV duration (170.2 vs 188.1 hours), hospital stays (21.1 vs 23.3 days) with reduced costs (22.1 vs 31.7 × 10⁴ NT$), and intra-hospital mortality (8.3 vs. 36.6%).

CONCLUSIONS

The ABCDE care bundle improved the outcome of acute renal failure patients with MV, especially shortening ICU stays and lowering medical costs and hospital mortality.

RELEVANCE TO CLINICAL PRACTICE

An ABCDE care bundle with an inter-professional, evidence-based, multicomponent ICU early mobilization management strategy can reduce ICU stays, hospital expenditure, and mortality among acute respiratory failure patients with MV.

Advances in the rehabilitation of intensive care unit acquired weakness: A case report on the promising use of robotics and virtual reality coupled to physiotherapy

INTRODUCTION

Traditional physiotherapy is currently the best approach to manage patients with intensive care unit acquired weakness (ICUAW). We report on a patient with ICUAW, who was provided with an intensive, in-patient regimen, that is, conventional plus robot-assisted physiotherapy. Aim of this case study was to assess the efficacy of a combined approach (conventional plus robot-assisted physiotherapy), on muscle strength, overall mobility, and disability burden in a patient with ICUAW in post-ICU intensive rehabilitation setting.

PATIENT CONCERNS

A 56-years-old male who was unable to stand and walk independently after hospitalization in an Intensive Care Unit. He initially was provided with daily sessions of conventional physiotherapy for 2 months, with mild results.

DIAGNOSIS

The patient was affected by ICUAW.

INTERVENTION

Given that the patient showed a relatively limited improvement after conventional physiotherapy, he was provided with daily sessions of robot-aided training for upper and lower limbs and virtual reality-aided rehabilitation for other 4 months, beyond conventional physiotherapy.

OUTCOMES

At the discharge (6 months after the admission), the patient reached the standing station and was able to ambulate with double support.

CONCLUSIONS

Our case suggests that patients with ICUAW should be intensively treated in in-patient regimen with robot-aided physiotherapy. Even though our approach deserves confirmation, the combined rehabilitation strategy may offer some advantage in maximizing functional recovery and containing disability.

Critical illness polyneuromyopathy in septic patients: Is it possible to diagnose it in a bedside clinical examination?

OBJECTIVE

To determine the sensitivity and specificity of peripheral and respiratory muscle strength tests in diagnosing critical illness polyneuromyopathy (CIPNM), compared with an electrophysiological examination.

METHODS

Fifty septic patients who required mechanical ventilation for at least five days, and without a previous history of muscle weakness, were included. Peripheral muscle strength was assessed using the Medical Research Council (MRC) score, handgrip strength by dynamometry, and respiratory muscle strength with maximum respiratory pressures. Diagnosis of CIPNM was either confirmed or rejected by an electrophysiological examination. Receiver operating characteristic curve analysis was performed to determine the cut-off values with the best sensitivity (SN) and specificity (SP) of the studied variables in the presence or absence of CIPNM.

RESULTS

Patients with CIPNM were older, more critical (APACHE IV/SAPS 3), had a longer hospitalization, required mechanical ventilation for longer, and had a higher rate of intensive care unit readmission. Cutoff values identified CIPNM patients using MRC scores, dynamometry according to sex, maximal expiratory and inspiratory pressures, as well as being confirmed by the electrophysiological examination, with good sensitivity and specificity: < 40 (SN: 0.893; SP: 0.955); < 7 kg (SN: 1; SP: 0.909) for men, < 4 kg (SN: 0.882; SP: 1) for women; < 34 cmH2O (SN: 0.808; SP: 0.909) and > -40 cmH2O (SN: 0.846; SP: 0.909), respectively.

CONCLUSION

The MRC score, dynamometry or maximum respiratory pressures can be used to identify patients with CIPNM at the intensive care bedside assessment. The healthcare professional can choose any of the methods studied to evaluate the patient, based on his experience and the resource available.

The Influence of Pain and Analgesia in Rodent Models of Sepsis

Sepsis is a multifaceted host response to infection that dramatically affects patient outcomes and the cost of health care. Animal models are necessary to replicate the complexity and heterogeneity of clinical sepsis. However, these models entail a high risk of pain and distress due to tissue trauma, inflammation, endotoxin-mediated hyperalgesia, and other mechanisms. Several recent studies and initiatives address the need to improve the welfare of animals through analgesics and standardize the models used in preclinical sepsis research. Ultimately, the goal is to provide high-fidelity, humane animal models that better replicate the clinical course of sepsis, to provide more effective translation and advance therapeutic discovery. The purpose of this review is to discuss the current understanding of the roles of pain and analgesia in rodent models of sepsis. The current definitions of sepsis along with an overview of pain in human sepsis are described. Finally, welfare concerns associated with animal models of sepsis and the most recent considerations for relief of pain and distress are reviewed.

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.

Computed Tomography Evidence of Psoas Muscle Atrophy Without Concomitant Tendon Wasting in Early Sepsis

BACKGROUND

Morphomic studies have demonstrated a correlation between sarcopenia and clinical outcomes in septic patients. However, tendon morphomics has not yet been studied in this context. The purpose of the present study was to evaluate tendon morphology in septic patients through analytic morphomics. We hypothesized that morphomic analyses would reveal concomitant muscle and tendon wasting in sepsis patients. The results of this study may help to implement different rehabilitation modalities for critically ill patients.

MATERIALS AND METHODS

The volume and fat content of bilateral psoas muscles and tendons were measured on abdominal computed tomography scans of 25 ICU septic and 25 control trauma patients admitted to the University of Michigan between 2011 and 2012. Univariate and multivariate analyses were performed to determine the relationship between psoas muscle and tendon morphometric data, and the association with clinical variables such as smoking and comorbidities.

RESULTS

Average psoas muscle volume was 12.21 ± 5.6 cm³ for control patients and 9.318 ± 3.3 cm³ in septic patients (P = 0.0023). The average psoas muscle/fat ratio for septic patients was 0.0288 ± 0.071 cm³, compared with 0.0107 ± 0.008 cm³ in the control group (P = 0.075). Average tendon volume in the septic population (0.508 ± 0.191 cm³) was not different than the control cohort (0.493 ± 0.182 cm³) (P = 0.692).

CONCLUSIONS

Our results demonstrate significantly smaller psoas muscle volume in septic patients than in age-, gender-, and BMI-matched trauma patients but no demonstrable change in tendon morphology between patient groups. These findings begin to define the boundaries of clinical application within the field of morphomics.

Physical Impairments Associated With Post-Intensive Care Syndrome: Systematic Review Based on the World Health Organization's International Classification of Functioning, Disability and Health Framework

BACKGROUND

Post-intensive care syndrome (PICS) is a constellation of new or worsening impairments in physical, mental, or cognitive abilities or a combination of these in individuals who have survived critical illness requiring intensive care.

PURPOSE

The 2 purposes of this systematic review were to identify the scope and magnitude of physical problems associated with PICS during the first year after critical illness and to use the World Health Organization's International Classification of Functioning, Disability and Health (ICF) framework to elucidate impairments of body functions and structures, activity limitations, and participation restrictions associated with PICS.

DATA SOURCES

Ovid MEDLINE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, CINAHL Plus with Full Text (EBSCO), Web of Science, and Embase were searched from inception until March 7, 2017.

STUDY SELECTION

Two reviewers screened titles, abstracts, and full text to independently determine study eligibility based on inclusion and exclusion criteria.

DATA EXTRACTION

Study methodological quality was assessed using the Newcastle-Ottawa Scale. Data describing study methods, design, and participant outcomes were extracted.

DATA SYNTHESIS

Fifteen studies were eligible for review. Within the first year following critical illness, people who had received intensive care experienced impairments in all 3 domains of the ICF (body functions and structures, activity limitations, and participation restrictions). These impairments included decreased pulmonary function, reduced strength of respiratory and limb muscles, reduced 6-minute walk test distance, reduced ability to perform activities of daily living and instrumental activities of daily living, and reduced ability to return to driving and paid employment.

LIMITATIONS

The inclusion of only 15 observational studies in this review may limit the generalizability of the findings.

CONCLUSIONS

During the first year following critical illness, individuals with PICS experienced physical impairments in all 3 domains of the ICF.

Acquired neuromuscular dysfunction in the intensive care unit

INTRODUCTION

Polyneuropathy and myopathy, grouped under the term «intensive care unit-acquired weakness» (ICUAW), are neuromuscular pathologies to which patients in the intensive care unit (ICU) are susceptible. They are multifactorial pathologies, prolonged connection to a ventilator is one of the most common. The objective of this review was to identify the efficacy of different rehabilitative treatments in patients with ICUAW, and the relationship between ICUAW and a series of indicators.

METHODS

A systematic review of the primary studies selected from the Medline, Scielo, Web of Science, Cochrane, Cuiden and Science Direct databases was carried out, following the guidelines of the PRISMA statement, by which the search protocol was established.

RESULTS AND CONCLUSIONS

Of 161 articles, only 10 were selected to be part of this review, in which a total of 717 patients admitted to the ICU were studied. A statistically significant relationship was observed between ICUAW and failure in ventilator disconnection, mortality, increase in ICU stay and the time that the patients required mechanical ventilation. Moreover, all this improved in this type of patients with the application of a rehabilitation therapy. The use of corticosteroids, was not shown to be related to neuromuscular alteration.

First-Episode Psychosis and Hypokalemia: A Case Report and Review of the Literature

Hypokalemia is the most frequent electrolyte abnormality seen in clinical practice. Hypokalemia is defined as serum potassium below 3.5 mEq/L and is usually asymptomatic and only identified in routine laboratory analysis. However, in some cases, symptoms include hypertension, palpitations, muscle weakness, easy fatigability, cramping and myalgias, memory impairment, disorientation and confusion, depressed or anxious mood, and irritability. Although rare, hypokalemia has been associated with psychosis. In particular, hypokalemia has been associated with psychotic exacerbations in patients with chronic psychotic disorder. We present a case report of a young female who developed a first presentation of acute psychosis and in which complementary investigations revealed hypokalemia. The psychosis resolved in few hours after replacement therapy with potassium chloride. The patient returned her usual functioning after discharge and there were no signs of psychosis at six-month follow-up.

Normal Baseline Function Is Associated With Delayed Rehabilitation in Critically Ill Children

BACKGROUND

Early mobilization of patients in the adult intensive care unit (ICU) is associated with improved functional outcomes and shorter ICU stay. Although emerging evidence suggests that early mobilization in pediatric ICUs (PICUs) is safe and feasible, physical therapist (PT) consultation may be delayed because of perceptions that patient acuity precludes mobilization activities. Factors that influence timely involvement of PTs to facilitate acute rehabilitation in critically ill children have not been characterized. The aim of this study was to identify patient-level factors for early PT consultation in a tertiary care PICU before large-scale implementation of a multicomponent early mobilization program.

METHODS

We conducted a retrospective analysis of data from the PICU Up! Quality Improvement Initiative. The primary outcome was early rehabilitation, defined as PT consultation within the first 3 days of PICU admission. Patients (n = 100) were divided into 2 groups by outcome, and predictive factors for early rehabilitation were analyzed with logistic regression.

RESULTS

Of 100 children, 54% received early rehabilitation. In univariate analyses, higher pediatric risk of mortality (PRISM) score (P < .001), baseline motor impairment (P < .01), developmental delay (P = .04), mechanical ventilation (P = .1), and number of devices (P = .01) were associated with early rehabilitation. In a logistic regression model, predictive factors for early rehabilitation included baseline motor impairment (adjusted odds ratio = 5.36, 95% confidence interval [CI] = 1.3-22.0) and higher PRISM score (adjusted odds ratio = 1.17, 95% CI = 1.02-1.34).

CONCLUSIONS

Critically ill children with normal baseline function or lower acuity of illness are less likely to have initiation of early rehabilitation with PT prior to implementation of a unit-wide early mobilization program. Baseline motor impairment and higher PRISM scores were independently associated with early rehabilitation. These findings highlight the need for streamlined criteria for PT consultation to meet the rehabilitation needs of all critically ill patients.

ICU-acquired weakness: should medical sovereignty belong to any specialist?

ICU-acquired weakness (ICUAW), including critical illness polyneuropathy, critical illness myopathy, and critical illness polyneuropathy and myopathy, is a frequent disabling disorder in ICU subjects. Research has predominantly been performed by intensivists, whose efforts have permitted the diagnosis of ICUAW early during an ICU stay and understanding of several of the pathophysiological and clinical aspects of this disorder. Despite important progress, the therapeutic strategies are unsatisfactory and issues such as functional outcomes and long-term recovery remain unclear. Studies involving multiple specialists should be planned to better differentiate the ICUAW types and provide proper functional outcome measures and follow-up. A more strict collaboration among specialists interested in ICUAW, in particular physiatrists, is desirable to plan proper care pathways after ICU discharge and to better meet the health needs of subjects with ICUAW.

Bundle Gel Fibers with a Tunable Microenvironment for in Vitro Neuron Cell Guiding

As scaffolds for neuron cell guiding in vitro, gel fibers with a bundle structure, comprising multiple microfibrils, were fabricated using a microfluidic device system by casting a phase-separating polymer blend solution comprising hydroxypropyl cellulose (HPC) and sodium alginate (Na-Alg). The topology and stiffness of the obtained bundle gel fibers depended on their microstructure derived by the polymer blend ratio of HPC and Na-Alg. High concentrations of Na-Alg led to the formation of small microfibrils in a one-bundle gel fiber and stiff characteristics. These bundle gel fibers permitted for the elongation of the neuron cells along their axon orientation with the long axis of fibers. In addition, human-induced pluripotent-stem-cell-derived dopaminergic neuron progenitor cells were differentiated into neuronal cells on the bundle gels. The bundle gel fibers demonstrated an enormous potential as cell culture scaffold materials with an optimal microenvironment for guiding neuron cells.

Critical care polyneuropathy in burn injuries: An integrative review

Polyneuropathy is a debilitating condition which may be associated with large burns. The aim of this integrative review is to identify factors that contribute to the development of critical care polyneuropathy in patients admitted to an intensive care unit with a severe burn injury. PubMed, Scopus, CINHAL and EMBASE were searched up until July 2016. Studies/case reports focusing on critical care polyneuropathy for burn injured patients were included. The ten studies, included a total of 2755 burns subjects and identified 128 critical care polyneuropathy patients with an incidence of 4.4%. Three case reports identified prolonged ventilation and development of critical care neuropathy. Overall, factors identified as contributing to the development of critical care polyneuropathy in burn injured patients included prolonged ventilation (>7 days), large and deep total body surface area burns (mean TBSA 40%), and sepsis. Critical care polyneuropathy in burn patients remains challenging to diagnose and treat. To date, there is a lack of long term studies describing the impact of critical care polyneuropathy on functional performance or participation in activities of daily living in the burns population and this is consistent with the general literature addressing the lack of follow up assessments and long term consequences of persistent muscle weakness.

Critical Illness Neuromyopathy Complicating Cardiac Surgery

Critical illness neuromyopathy (CINM) is a sporadically reported disease in the setting of an intensive care unit developing in the process of managing a critical illness. The disease primarily affects the motor and sensory axons and results in severe limb weakness rendering ventilator weaning extremely difficult. We report a case of CINM after cardiac valve surgery. Quadriplegia developed after the operation and resolved slowly over the following 2 months. The patient was discharged home free of neurologic symptoms.

A Randomized Trial of an Intensive Physical Therapy Program for Patients with Acute Respiratory Failure

RATIONALE

Early physical therapy (PT) interventions may benefit patients with acute respiratory failure by preventing or attenuating neuromuscular weakness. However, the optimal dosage of these interventions is currently unknown.

OBJECTIVES

To determine whether an intensive PT program significantly improves long-term physical functional performance compared with a standard-of-care PT program.

METHODS

Patients who required mechanical ventilation for at least 4 days were eligible. Enrolled patients were randomized to receive PT for up to 4 weeks delivered in an intensive or standard-of-care manner. Physical functional performance was assessed at 1, 3, and 6 months in survivors who were not currently in an acute or long-term care facility. The primary outcome was the Continuous Scale Physical Functional Performance Test short form (CS-PFP-10) score at 1 month.

MEASUREMENTS AND MAIN RESULTS

A total of 120 patients were enrolled from five hospitals. Patients in the intensive PT group received 12.4 ± 6.5 sessions for a total of 408 ± 261 minutes compared with only 6.1 ± 3.8 sessions for 86 ± 63 minutes in the standard-of-care group (P < 0.001 for both analyses). Physical function assessments were available for 86% of patients at 1 month, for 76% at 3 months, and for 60% at 6 months. In both groups, physical function was reduced yet significantly improved over time between 1, 3, and 6 months. When we compared the two interventions, we found no differences in the total CS-PFP-10 scores at all three time points (P = 0.73, 0.29, and 0.43, respectively) or in the total CS-PFP-10 score trajectory (P = 0.71).

CONCLUSIONS

An intensive PT program did not improve long-term physical functional performance compared with a standard-of-care program. Clinical trial registered with www.clinicaltrials.gov (NCT01058421).

A novel paradigm links mitochondrial dysfunction with muscle stem cell impairment in sepsis

Sepsis is an acute systemic inflammatory response of the body to microbial infection and a life threatening condition associated with multiple organ failure. Survivors may display long-term disability with muscle weakness that remains poorly understood. Recent data suggest that long-term myopathy in sepsis survivors is due to failure of skeletal muscle stem cells (satellite cells) to regenerate the muscle. Satellite cells impairment in the acute phase of sepsis is linked to unusual mitochondrial dysfunctions, characterized by a dramatic reduction of the mitochondrial mass and hyperactivity of residual organelles. Survivors maintain the impairment of satellite cells, including alterations of the mitochondrial DNA (mtDNA), in the long-term. This condition can be rescued by treatment with mesenchymal stem cells (MSCs) that restore mtDNA alterations and mitochondrial function in satellite cells, and in fine their regenerative potential. Injection of MSCs in turn increases the force of isolated muscle fibers and of the whole animal, and improves the survival rate. These effects occur in the context of reduced inflammation markers that also raised during sepsis. Targeting muscle stem cells mitochondria, in a context of reduced inflammation, may represent a valuable strategy to reduce morbidity and long-term impairment of the muscle upon sepsis.

Progressive mobility as a team effort in transitional care

With changing health care, progressive care nurses are working in diverse practice settings to meet patient care needs. Progressive care is practiced along the continuum from the intensive care unit to home. The benefits of early progressive mobility are examined with a focus on the interdisciplinary collaboration for care in a transitional care program of a skilled nursing facility. The program's goals are improved functional status, self-care management, and home discharge with reduced risk for hospital readmission. The core culture of the program is interdisciplinary collaboration and team partnership for care of patients and their families.

Early Mobilization Reduces Duration of Mechanical Ventilation and Intensive Care Unit Stay in Patients With Acute Respiratory Failure

OBJECTIVE

To evaluate the effects of a quality improvement program to introduce early mobilization on the outcomes of patients with mechanical ventilation (MV) in the intensive care unit (ICU).

DESIGN

A retrospective observational study.

SETTING

Nineteen-bed ICU at a medical center.

PARTICIPANTS

Adults patients with MV (N=153) admitted to a medical ICU.

INTERVENTIONS

A multidisciplinary team (critical care nurse, nursing assistant, respiratory therapist, physical therapist, patient's family) initiated the protocol within 72 hours of MV when patients become hemodynamically stable. We did early mobilization twice daily, 5d/wk during family visits (30min each time), and cooperated with family, if possible.

MAIN OUTCOME MEASURES

MV duration, rate of successful weaning, and length of ICU and hospital stay.

RESULTS

We enrolled 63 patients in the before protocol group and 90 in the after protocol group. The 2 groups were well matched in age, sex, body height, body weight, body mass index, disease severity, cause of intubation, number of comorbidities, and most underlying diseases. After protocol group patients had shorter MV durations (4.7d vs 7.5d; P<.001) and ICU stays (6.9d vs 9.9d; P=.001) than did before protocol group patients. Early mobilization was negatively associated with the duration of MV (β=-.269; P<.002; 95% confidence interval [CI], -4.767 to -1.072), and the risk of MV for ≥7 days was lower in patients who underwent early mobilization (odds ratio, .082; 95% CI, .021-.311).

CONCLUSIONS

The introduction of early mobilization for patients with MV in the ICU shortened MV durations and ICU stays. A multidisciplinary team that includes the patient's family can work together to improve the patient's clinical outcomes.

Critical illness myopathy in a cervical spine-injured patient

Neuromuscular weakness acquired in the intensive care unit (ICU) causes significant impairment in critically ill patients. The spectrum of critical illness neuromuscular disease includes critical illness myopathy, critical illness polyneuropathy or both, and occurs in approximately one-third of patients admitted to the ICU and those who are ventilated for at least 7 days. Recognized risk factors include sepsis, systemic inflammatory response syndrome, multi-organ failure, neuromuscular blocking agents and corticosteroids, however the absence of predisposing factors should not preclude critical illness neuromuscular disease. A 23-year-old male suffered a cervical spine injury and was admitted to the ICU. Two weeks post admission, he lost all power in his upper limbs, neck and face. Nerve conduction studies and needle electromyography were performed 4 weeks and 3 months after the injury, suggesting that myopathy was the likely cause of weakness. The definitive diagnosis of critical illness myopathy was based on muscle biopsy demonstrating myosin filament loss. Evaluation of new-onset weakness in ICU patients is essential to distinguish neurological causes from complications of critical illness. Signs and symptoms of critical illness neuromuscular disease must be identified early to encourage recovery, promote rehabilitation, and reduce morbidity and mortality.

Neuromuscular Dysfunction in Experimental Sepsis and Glutamine

BACKGROUND

Electrophysiological studies show that critical illness polyneuromyopathy appears in the early stage of sepsis before the manifestation of clinical findings. The metabolic response observed during sepsis causes glutamine to become a relative essential amino acid.

AIMS

We aimed to assess the changes in neuromuscular transmission in the early stage of sepsis after glutamine supplementation.

STUDY DESIGN

Animal experimentation.

METHODS

Twenty male Sprague-Dawley rats were randomized into two groups. Rats in both groups were given normal feeding for one week. In the study group, 1 g/kg/day glutamine was added to normal feeding by feeding tube for one week. Cecal ligation and perforation (CLP) surgery was performed at the end of one week. Before and 24 hours after CLP, compound muscle action potentials were recorded from the gastrocnemius muscle.

RESULTS

Latency measurements before and 24 hours after CLP were 0.68±0.05 ms and 0.80±0.09 ms in the control group and 0.69±0.07 ms and 0.73±0.07 ms in the study group (p<0.05).

CONCLUSION

Since enteral glutamine prevented compound muscle action potentials (CMAP) latency prolongation in the early phase of sepsis, it was concluded that enteral glutamine replacement might be promising in the prevention of neuromuscular dysfunction in sepsis; however, further studies are required.

The impairment of small nerve fibers in severe sepsis and septic shock

Background

A decrease of small nerve fibers in skin biopsies during the course of critical illness has been demonstrated recently. However, the diagnostic use of skin biopsies in sepsis and its time course is not known.

Methods

Patients (n=32) with severe sepsis or septic shock were examined using skin biopsies, neurological examination, nerve conduction studies, and sympathetic skin response in the first week after onset of sepsis, 2 weeks and 4 months later and compared to gender- and age-matched healthy controls.

Results

Skin biopsies at the ankle and thigh revealed a significant decrease of intraepidermal nerve fiber density (IENFD) during the first week of sepsis and 2 weeks later. All patients developed critical illness polyneuropathy (CIP) according to electrophysiological criteria and 11 showed IENFD values lower than the 0.05 quantile. Four patients were biopsied after 4 months and still showed decreased IENFD. Results of nerve conduction studies and IENFD did considerably change over time. No differences for survival time between patients with IEFND lower and larger than 3.5 fibers/mm were found.

Conclusions

Skin biopsy is able to detect an impairment of small sensory nerve fibers early in the course of sepsis. However, it may not be suited as a prognostic parameter for survival.

Trial registration

German Clinical Trials Register, DRKS-ID: DRKS00000642, 12/17/2010

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-016-1241-5) contains supplementary material, which is available to authorized users.

Quantitative neuromuscular ultrasound in intensive care unit-acquired weakness: A systematic review

Intensive care unit-acquired weakness (ICU-AW) causes significant morbidity and impairment in critically ill patients. Recent advances in neuromuscular ultrasound (NMUS) allow evaluation of neuromuscular pathology early in critical illness. Here we review application of ultrasound in ICU-AW. MEDLINE-indexed articles were searched for terms relevant to ultrasound and critical illness. Two reviewers evaluated the resulting abstracts (n = 218) and completed full-text review (n = 13). Twelve studies and 1 case report were included. Ten studies evaluated muscle thickness or cross-sectional area (CSA): 8 reported a decrease, and 2 reported no change. Two studies reported preservation of muscle thickness in response to neuromuscular electrical stimulation, and 1 found no preservation. One study found decreases in gray-scale standard deviation, but no change in echogenicity. One study described increases in echogenicity and fasciculations. Ultrasound reliability in ICU-AW is not fully established. Further investigation is needed to identify ultrasound measures that reliably predict clinical, electrodiagnostic, and pathologic findings of ICU-AW.

Clinical review: intensive care unit acquired weakness

A substantial number of patients admitted to the ICU because of an acute illness, complicated surgery, severe trauma, or burn injury will develop a de novo form of muscle weakness during the ICU stay that is referred to as “intensive care unit acquired weakness” (ICUAW). This ICUAW evoked by critical illness can be due to axonal neuropathy, primary myopathy, or both. Underlying pathophysiological mechanisms comprise microvascular, electrical, metabolic, and bioenergetic alterations, interacting in a complex way and culminating in loss of muscle strength and/or muscle atrophy. ICUAW is typically symmetrical and affects predominantly proximal limb muscles and respiratory muscles, whereas facial and ocular muscles are often spared. The main risk factors for ICUAW include high severity of illness upon admission, sepsis, multiple organ failure, prolonged immobilization, and hyperglycemia, and also older patients have a higher risk. The role of corticosteroids and neuromuscular blocking agents remains unclear. ICUAW is diagnosed in awake and cooperative patients by bedside manual testing of muscle strength and the severity is scored by the Medical Research Council sum score. In cases of atypical clinical presentation or evolution, additional electrophysiological testing may be required for differential diagnosis. The cornerstones of prevention are aggressive treatment of sepsis, early mobilization, preventing hyperglycemia with insulin, and avoiding the use parenteral nutrition during the first week of critical illness. Weak patients clearly have worse acute outcomes and consume more healthcare resources. Recovery usually occurs within weeks or months, although it may be incomplete with weakness persisting up to 2 years after ICU discharge. Prognosis appears compromised when the cause of ICUAW involves critical illness polyneuropathy, whereas isolated critical illness myopathy may have a better prognosis. In addition, ICUAW has shown to contribute to the risk of 1-year mortality. Future research should focus on new preventive and/or therapeutic strategies for this detrimental complication of critical illness and on clarifying how ICUAW contributes to poor longer-term prognosis.

The Sick and the Weak: Neuropathies/Myopathies in the Critically Ill

Critical illness polyneuropathies (CIP) and myopathies (CIM) are common complications of critical illness. Several weakness syndromes are summarized under the term intensive care unit-acquired weakness (ICUAW). We propose a classification of different ICUAW forms (CIM, CIP, sepsis-induced, steroid-denervation myopathy) and pathophysiological mechanisms from clinical and animal model data. Triggers include sepsis, mechanical ventilation, muscle unloading, steroid treatment, or denervation. Some ICUAW forms require stringent diagnostic features; CIM is marked by membrane hypoexcitability, severe atrophy, preferential myosin loss, ultrastructural alterations, and inadequate autophagy activation while myopathies in pure sepsis do not reproduce marked myosin loss. Reduced membrane excitability results from depolarization and ion channel dysfunction. Mitochondrial dysfunction contributes to energy-dependent processes. Ubiquitin proteasome and calpain activation trigger muscle proteolysis and atrophy while protein synthesis is impaired. Myosin loss is more pronounced than actin loss in CIM. Protein quality control is altered by inadequate autophagy. Ca(2+) dysregulation is present through altered Ca(2+) homeostasis. We highlight clinical hallmarks, trigger factors, and potential mechanisms from human studies and animal models that allow separation of risk factors that may trigger distinct mechanisms contributing to weakness. During critical illness, altered inflammatory (cytokines) and metabolic pathways deteriorate muscle function. ICUAW prevention/treatment is limited, e.g., tight glycemic control, delaying nutrition, and early mobilization. Future challenges include identification of primary/secondary events during the time course of critical illness, the interplay between membrane excitability, bioenergetic failure and differential proteolysis, and finding new therapeutic targets by help of tailored animal models.

Small-nerve-fiber pathology in critical illness documented by serial skin biopsies

INTRODUCTION

Small-fiber pathology can develop in the acute phase of critical illness and may explain chronic sensory impairment and pain in critical care survivors.

METHODS

Eleven adult ischemic stroke patients in a neurocritical care unit were enrolled in an observational cohort study. Intraepidermal nerve fiber density (IENFD) in the distal leg was assessed on admission to the intensive care unit and 10-14 days later, together with electrophysiological testing.

RESULTS

Of the 11 patients recruited, 9 (82%) had sepsis or multiple-organ failure. Median IENFD on admission (5.05 fibers/mm) decreased significantly to 2.18 fibers/mm (P < 0.001), and abnormal IENFD was found in 6 patients (54.5%). Electrodiagnostic signs of large-fiber neuropathy and/or myopathy were found in 6 patients (54.5%), and autonomic dysfunction was found in 2 patients (18.2%).

CONCLUSION

Serial IENFD measurements confirmed the development of small-fiber sensory involvement in the acute phase of critical illness.

Impact of ICU-acquired weakness on post-ICU physical functioning: a follow-up study

Introduction

ICU-acquired weakness is thought to mediate physical impairments in survivors of critical illness, but few studies have investigated this thoroughly. The purpose was to investigate differences in post-ICU mortality and physical functioning between patients with and without ICU-acquired weakness at 6 months after ICU discharge.

Method

ICU patients, mechanically ventilated ≥2 days, were included in a single-center prospective observational cohort study. ICU-acquired weakness was diagnosed when the average Medical Research Council score was <4 in awake and attentive patients. Post-ICU mortality was recorded until 6 months after ICU discharge; in surviving patients, physical functioning was assessed using the Short-Form Health Survey physical functioning domain. The independent effect of ICU-acquired weakness on post-ICU mortality was analyzed using a multivariable Cox proportional hazards model. The independent effect of ICU-acquired weakness on the physical functioning domain score was analyzed using a multivariable linear regression model.

Results

Of the 156 patients included, 80 had ICU-acquired weakness. Twenty-three patients died in the ICU (20 with ICU-acquired weakness); during 6 months follow-up after ICU discharge another 25 patients died (17 with ICU-acquired weakness). Physical functioning domain scores were available for 96 survivors (39 patients with ICU-acquired weakness). ICU-acquired weakness was independently associated with an increase in post-ICU mortality (hazard ratio 3.6, 95% confidence interval, 1.3 to 9.8; P = 0.01) and with a decrease in physical functioning (β: -16.7 points; 95% confidence interval, -30.2 to -3.1; P = 0.02).

Conclusion

ICU-acquired weakness is independently associated with higher post-ICU mortality and with clinically relevant lower physical functioning in survivors at 6 months after ICU discharge.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-0937-2) contains supplementary material, which is available to authorized users.

The incidence of intensive care unit-acquired weakness syndromes: A systematic review

We conducted a literature review of the intensive care unit-acquired weakness syndromes (critical illness polyneuropathy, critical illness myopathy and critical illness neuromyopathy) with the primary objective of determining their incidence as a combined group. Studies were identified through MEDLINE, Embase, Cochrane Database and article reference list searches and were included if they evaluated the incidence of one or more of these conditions in an adult intensive care unit population. The incidence of an intensive care unit-acquired weakness syndrome in the included studies was 40% (1080/2686 patients, 95% confidence interval 38-42%). The intensive care unit populations included were heterogeneous though largely included patients receiving mechanical ventilation for seven or more days. Additional prespecified outcomes identified that the incidence of intensive care unit-acquired weakness varied with the diagnostic technique used, being lower with clinical (413/1276, 32%, 95% CI 30-35%) compared to electrophysiological techniques (749/1591, 47%, 95% CI 45-50%). Approximately a quarter of patients were not able to comply with clinical evaluation and this may be responsible for potential underreporting of this condition.