Critical illness polyneuropathy and myopathy in the intensive care unit

Early detection of low QRS voltage and its association with mortality in patients with sepsis

Various electrocardiographic changes occur during sepsis, but data on the clinical importance of a low QRS voltage in sepsis are still limited. We aimed to evaluate the association between low QRS voltage identified early in sepsis and mortality in patients with sepsis. Between September 2019 and December 2020, all consecutive adult patients diagnosed with sepsis in the emergency room or general ward at Samsung Medical Center were enrolled. Patients without a 12-lead electrocardiogram recorded within 48 h of recognition of sepsis were excluded. In 432 eligible patients, 12-lead electrocardiogram was recorded within the median of 24 min from the first recognition of sepsis, and low QRS voltage was identified in 115 (26.6%) patients. The low QRS group showed more severe organ dysfunction and had higher levels of N-terminal pro-brain natriuretic peptide. The hospital mortality was significantly higher in the low QRS voltage group than in the normal QRS voltage group (49.6% vs. 28.1%, p < 0.001). Similarly, among the 160 patients who required intensive care unit admission, significantly more patients in the low QRS group died in the intensive care unit (35.9% vs. 18.2%, p = 0.021). Low QRS voltage was associated with increased hospital mortality in patients with sepsis.

Patterns of Unwanted Biological and Technical Expression Variation Among 49 Human Tissues

Tissue gene expression studies are impacted by biological and technical sources of variation, which can be broadly classified into wanted and unwanted variation. The latter, if not addressed, results in misleading biological conclusions. Methods have been proposed to reduce unwanted variation, such as normalization and batch correction. A more accurate understanding of all causes of variation could significantly improve the ability of these methods to remove unwanted variation while retaining variation corresponding to the biological question of interest. We used 17,282 samples from 49 human tissues in the Genotype-Tissue Expression data set (v8) to investigate patterns and causes of expression variation. Transcript expression was transformed to z-scores, and only the most variable 2% of transcripts were evaluated and clustered based on coexpression patterns. Clustered gene sets were assigned to different biological or technical causes based on histologic appearances and metadata elements. We identified 522 variable transcript clusters (median: 11 per tissue) among the samples. Of these, 63% were confidently explained, 16% were likely explained, 7% were low confidence explanations, and 14% had no clear cause. Histologic analysis annotated 46 clusters. Other common causes of variability included sex, sequencing contamination, immunoglobulin diversity, and compositional tissue differences. Less common biological causes included death interval (Hardy score), disease status, and age. Technical causes included blood draw timing and harvesting differences. Many of the causes of variation in bulk tissue expression were identifiable in the Tabula Sapiens data set of single-cell expression. This is among the largest explorations of the underlying sources of tissue expression variation. It uncovered expected and unexpected causes of variable gene expression and demonstrated the utility of matched histologic specimens. It further demonstrated the value of acquiring meaningful tissue harvesting metadata elements to use for improved normalization, batch correction, and analysis of both bulk and single-cell RNA-seq data.

THE EFFECT OF IN-BED LEG CYCLING EXERCISES ON MUSCLE STRENGTH IN PATIENTS WITH INTENSIVE CARE UNIT-ACQUIRED WEAKNESS: A SINGLE-CENTER RETROSPECTIVE STUDY

Objective

To examine the effect of in-bed leg cycling exercise on patients with intensive care unit-acquired weakness (ICU-AW).

Design

Single-center retrospective study.

Subjects/Patients

Patients admitted to the ICU between January 2019 and March 2023 were enrolled in the ergometer group, and those admitted to the ICU between August 2017 and December 2018 were enrolled in the control group.

Methods

The ergometer group performed in-bed leg cycling exercises 5 times per week for 20 min from the day of ICU-AW diagnosis. Furthermore, the ergometer group received 1 early mobilization session per day according to the early mobilization protocol, whereas the control group received 1 or 2 sessions per day. The number of patients with recovery from ICU-AW at ICU discharge and improvement in physical functions were compared.

Results

Significantly more patients in the ergometer group recovered from ICU-AW than in the control group (87.0% vs 60.6%, p = 0.039). Regarding physical function, the ergometer group showed significantly higher improvement efficiency in Medical Research Council sum score (1.0 [0.7-2.1] vs 0.1 [0.0-0.2], p < 0.001).

Conclusion

In-bed leg cycling exercise, in addition to the early mobilization protocol, reduced the number of patients with ICU-AW at ICU discharge.

Serum neurofilament light chain as an early diagnostic biomarker for critical illness polyneuropathy

BACKGROUND

Critical illness polyneuropathy (CIP) commonly occurs in critical care unit (CCU) patients, but timely diagnosis can be challenging. Therefore, new biomarkers, such as serum neurofilament light chain (sNfL), could help to improve early identification of patients with this condition.

METHODS

CIP was diagnosed or excluded with neurological assessment and nerve conduction measurement in a prospective study of CCU patients. sNfL and secondary predictors for neuropathy (neuron-specific enolase (NSE), S100, folic acid, and vitamin B12) were measured at admission. Cases and controls were compared regarding the predictors.

RESULTS

Nineteen patients met the inclusion criteria. CIP was considered definitely or most likely present in seven (37%, cases) and definitely or most likely absent in 12 individuals (63%, controls). At admission, sNfL levels were significantly higher in the cases than in the controls: 405 (IQR 77 to 835) vs. 27 (IQR 12 to 90) pg/mL; difference of medians 375, 95% confidence interval [14, 736], pg/mL; P=0.04. We found no significant differences regarding the secondary predictors at baseline. Cases had longer durations of CCU stay (median 19 (IQR 11 to 44) vs. 8 (IQR five to ten) and increased mortality (57% vs. 33% deceased) compared to controls.

CONCLUSIONS

Levels of serum neurofilament light chain are higher in patients who develop CIP soon after CCU admission and might be helpful in identifying those individuals early.

Lower serum cholesterol levels as a risk factor for critical illness polyneuropathy: a matched case-control study

Critical illness polyneuropathy (CIP) is a frequent and underdiagnosed phenomenon among intensive care unit patients. The lipophilic nature of neuronal synapses may result in the association of low serum cholesterol levels with a higher rate of CIP development. We aimed to investigate this issue in critically ill patients. All cases diagnosed with CIP in our tertiary care hospital between 2013 and 2017 were 1:1 matched with controls without the condition by age, sex, and ICD diagnoses. The main risk factors examined were the differences in change between initial and minimum serum total cholesterol levels, and minimum serum total cholesterol levels between matched pairs. Other predictors were serum markers of acute inflammation. We included 67 cases and 67 controls (134 critically ill patients, 49% female, 46% medical). Serum total cholesterol levels decreased more profoundly in cases than controls (median: -74 (IQR -115 to -24) vs. -39 (IQR -82 to -4), median difference: -28, 95% CI [-51, -5]), mg/dl). Minimum serum total cholesterol levels were lower in the cases (median difference: -24, 95% CI [-39, -9], mg/dl). We found significant median differences across matched pairs in maximum serum C-reactive protein (8.9, 95% CI [4.6, 13.2], mg/dl), minimum albumin (-4.2, 95% CI [-6.7, -1.7], g/l), decrease in albumin (-3.9, 95% CI [-7.6, -0.2], g/l), and lowest cholinesterase levels (-0.72, 95% CI [-1.05, -0.39], U/l). Subsequently, more pronounced decreases in serum total cholesterol levels and lower minimum total cholesterol levels during critical care unit hospitalizations may be a risk factor for CIP.

Prevalence and prognostic value of neurological affections in hospitalized patients with moderate to severe COVID-19 based on objective assessments

Neurological manifestations of coronavirus disease 2019 (COVID-19) have been frequently described. In this prospective study of hospitalized COVID-19 patients without a history of neurological conditions, we aimed to analyze their prevalence and prognostic value based on established, standardized and objective methods. Patients were investigated using a multimodal electrophysiological approach, accompanied by neuropsychological and neurological examinations. Prevalence rates of central (CNS) and peripheral (PNS) nervous system affections were calculated and the relationship between neurological affections and mortality was analyzed using Firth logistic regression models. 184 patients without a history of neurological diseases could be enrolled. High rates of PNS affections were observed (66% of 138 patients receiving electrophysiological PNS examination). CNS affections were less common but still highly prevalent (33% of 139 examined patients). 63% of patients who underwent neuropsychological testing (n = 155) presented cognitive impairment. Logistic regression models revealed pathology in somatosensory evoked potentials as an independent risk factor of mortality (Odds Ratio: 6.10 [1.01-65.13], p = 0.049). We conclude that hospitalized patients with moderate to severe COVID-19 display high rates of PNS and CNS affection, which can be objectively assessed by electrophysiological examination. Electrophysiological assessment may have a prognostic value and could thus be helpful to identify patients at risk for deterioration.

A Comparison of Long-Term Outcomes in Patients Managed With Venovenous Extracorporeal Membrane Oxygenation in the First and Second Waves of the COVID-19 Pandemic in the United Kingdom

OBJECTIVES

Early studies of venovenous extracorporeal membrane oxygenation (ECMO) in COVID-19 have revealed similar outcomes to historical cohorts. Changes in the disease and treatments have led to differences in the patients supported on venovenous ECMO in the first and second waves. We aimed to compare these two groups in both the acute and follow-up phase.

DESIGN

Retrospective single-center cohort study comparing mortality at censoring date (November 30, 2021) and decannulation, patient characteristics, complications and lung function and quality of life (QOL-by European Quality of Life 5 Dimensions 3 Level Version) at first follow-up in patients supported on venovenous ECMO between wave 1 and wave 2 of the COVID-19 pandemic.

SETTING

Critical care department of a severe acute respiratory failure service.

PATIENTS

Patients supported on ECMO for COVID-19 between wave 1 (March 17, 2020, to August 31, 2020) and wave 2 (January 9, 2020, to May 25, 2021).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

One hundred twenty-three patients were included in our analysis. Survival at censoring date (χ 2 , 6.35; p = 0.012) and decannulation (90.4% vs 70.0%; p < 0.001) was significantly lower in the second wave, while duration of ECMO run was longer (12.0 d [18.0-30.0 d] vs 29.5 d [15.5-58.3 d]; p = 0.005). Wave 2 patients had longer application of noninvasive ventilation (NIV) prior to ECMO and a higher frequency of barotrauma. Patient age and NIV use were independently associated with increased mortality (odds ratio 1.07 [1.01-1.14]; p = 0.025 and 3.37 [1.12-12.60]; p = 0.043, respectively). QOL and lung function apart from transfer coefficient of carbon monoxide corrected for hemoglobin was similar at follow-up across the waves.

CONCLUSIONS

Most patients with COVID-19 supported on ECMO in both waves survived in the short and longer term. At follow-up patients had similar lung function and QOL across the two waves. This suggests that ECMO has an ongoing role in the management of a carefully selected group of patients with COVID-19.

Patterns of unwanted biological and technical expression variation across 49 human tissues

All tissue-based gene expression studies are impacted by biological and technical sources of variation. Numerous methods are used to normalize and batch correct these datasets. A more accurate understanding of all causes of variation could further optimize these approaches. We used 17,282 samples from 49 tissues in the Genotype Tissue Expression (GTEx) dataset (v8) to investigate patterns and causes of expression variation. Transcript expression was normalized to Z-scores and only the most variable 2% of transcripts were evaluated and clustered based on co-expression patterns. Clustered gene sets were solved to different biological or technical causes related to metadata elements and histologic images. We identified 522 variable transcript clusters (median 11 per tissue) across the samples. Of these, 64% were confidently explained, 15% were likely explained, 7% were low confidence explanations and 14% had no clear cause. Common causes included sex, sequencing contamination, immunoglobulin diversity, and compositional tissue differences. Less common biological causes included death interval (Hardy score), muscle atrophy, diabetes status, and menopause. Technical causes included brain pH and harvesting differences. Many of the causes of variation in bulk tissue expression were identifiable in the Tabula Sapiens dataset of single cell expression. This is the largest exploration of the underlying sources of tissue expression variation. It uncovered expected and unexpected causes of variable gene expression. These identified sources of variation will inform which metadata to acquire with tissue harvesting and can be used to improve normalization, batch correction, and analysis of both bulk and single cell RNA-seq data.

Perceived barriers to mobility in the intensive care units of Singapore: The Patient Mobilisation Attitudes and Beliefs Survey for the intensive care units

Purpose

Prolonged bed rest and immobility in the intensive care units (ICU) increase the risk of ICU-acquired weakness (ICUAW) and other complications. Mobilisation has been shown to improve patient outcomes but may be limited by the perceived barriers of healthcare professionals to mobilisation. The Patient Mobilisation Attitudes and Beliefs Survey for the ICU (PMABS-ICU) was adapted to assess perceived barriers to mobility in the Singapore context (PMABS-ICU-SG).

Methods

The 26-item PMABS-ICU-SG was disseminated to doctors, nurses, physiotherapists, and respiratory therapists working in ICU of various hospitals across Singapore. Overall and subscale (knowledge, attitude, and behaviour) scores were obtained and compared with the clinical roles, years of work experience, and type of ICU of the survey respondents.

Results

A total of 86 responses were received. Of these, 37.2% (32/86) were physiotherapists, 27.9% (24/86) were respiratory therapists, 24.4% (21/86) were nurses and 10.5% (9/86) were doctors. Physiotherapists had significantly lower mean barrier scores in overall and all subscales compared to nurses (p < 0.001), respiratory therapists (p < 0.001), and doctors (p = 0.001). A poor correlation (r = 0.079, p < 0.05) was found between years of experience and the overall barrier score. There was no statistically significant difference in the overall barriers score between types of ICU (χ2(2) = 4.720, p = 0.317).

Conclusion

In Singapore, physiotherapists had significantly lower perceived barriers to mobilisation compared to the other three professions. Years of experience and type of ICU had no significance in relation to barriers to mobilisation.

Feasibility of Muscle Endurance Testing in Critically Ill Trauma Patients: A Pilot Study

Intensive care unit-acquired weakness (ICUAW) occurs secondary to patients treated for life-threatening conditions in the ICU being diagnosed based on the Medical Research Council sum score (MRC-SS). However, patients often complain of fatigability and poor endurance, which are not evaluated by muscle strength. In this study, we explored the feasibility of assessing muscle quality and endurance in trauma ICU patients. The modified Functional Index-2 (FI2) testing was applied to evaluate muscle endurance. The maximal voluntary contraction (MVC) was measured when evaluating the MRC-SS using surface electromyography (sEMG), and the fatigue index (FI) was also recorded at the time of endurance testing. The ultrasonic muscle echogenicity by gray-scale analysis of rectus femoris (RF) and tibialis anterior (TA) muscles was evaluated at the initial (<72 h) and end of ICU care. A total of 14 patients were enrolled in this study. Fatigue was induced in eight patients (fatigue group), and six (non-fatigue group) completed endurance testing. All patients except one had an MRC-SS exceeding 48 points. There was no difference in US echogenicity, MRC-SS, and FI between groups. In sEMG, the root mean square (RMS) values of MVC in RF and TA muscles showed a significant difference (p < 0.05). To evaluate and predict the functional activity of ICU patients, measuring muscle strength alone is insufficient, and it is necessary to evaluate muscle endurance. In this respect, the modified FI2 test and sEMG monitoring are considered to be promising procedures for evaluating the muscle condition of critically ill patients even in complex situations in the ICU.

Early detection of ICU-acquired weakness in septic shock patients ventilated longer than 72 h

PURPOSE

ICU-acquired weakness, comprising Critical Illness Polyneuropathy (CIP) and Myopathy (CIM) is associated with immobilization and prolonged mechanical ventilation. This study aims to assess feasibility of early detection of CIP and CIM by peroneal nerve test (PENT) and sensory sural nerve action potential (SNAP) screening in patients with septic shock and invasively ventilated for more than 72 h.

METHODS

We performed repetitive PENT screening from 72 h after intubation until detecting a pathological response. We tested SNAPs in pathological PENT to differentiate CIP from CIM. We performed muscle strength examination in awake patients and recorded time from intubation to first in-bed and out-of-bed mobilization.

RESULTS

Eighteen patients were screened with PENT and 88.9% had abnormal responses. Mean time between intubation and first screening was 94.38 (± 22.41) hours. Seven patients (38.9%) had CIP, two (11.1%) had CIM, one (5.6%) had CIP and CIM, six (33.3%) had a pathological response on PENT associated with ICU-acquired weakness (but no SNAP could be performed to differentiate between CIP and CIM) and two patients had (11.1%) had no peripheral deficit. In patients where it could be performed, muscle strength testing concorded with electrophysiological findings. Twelve patients (66.7%) had out-of-bed mobilization 10.8 (± 7.4) days after admission.

CONCLUSION

CIP and CIM are frequent in septic shock patients and can be detected before becoming symptomatic with simple bedside tools. Early detection of CIP and CIM opens new possibilities for their timely management through preventive measures such as passive and active mobilization.

A First View of the Effect of a Trial of Early Mobilization on the Muscle Strength and Activities of Daily Living in Mechanically Ventilated Patients With COVID-19

Objective

Design

Setting

Participants

Interventions

Main Outcome Measures

Results

Conclusion

Sepsis-associated neuroinflammation in the spinal cord

Septic patients commonly present with central nervous system (CNS) disorders including impaired consciousness and delirium. Today, the main mechanism regulating sepsis-induced cerebral disorders is believed to be neuroinflammation. However, it is unknown how another component of the CNS, the spinal cord, is influenced during sepsis. In the present study, we intraperitoneally injected mice with lipopolysaccharide (LPS) to investigate molecular and immunohistochemical changes in the spinal cord of a sepsis model. After LPS administration in the spinal cord, pro-inflammatory cytokines including interleukin (IL)-1β, IL-6, and tumor necrosis factor alpha mRNA were rapidly and drastically induced. Twenty-four-hour after the LPS injection, severe neuronal ischemic damage spread into gray matter, especially around the anterior horns, and the anterior column had global edematous changes. Immunostaining analyses showed that spinal microglia were significantly activated and increased, but astrocytes did not show significant change. The current results indicate that sepsis induces acute neuroinflammation, including microglial activation and pro-inflammatory cytokine upregulation in the spinal cord, causing drastic neuronal ischemia and white matter edema in the spinal cord.

Mortality and its risk factors in critically ill patients with connective tissue diseases: A meta-analysis

BACKGROUND

Systemic lupus erythematosus (SLE), primary Sjögren's syndrome (pSS), systemic sclerosis (SSc), idiopathic inflammatory myopathies (IIM) and rheumatoid arthritis (RA) are connective tissue diseases (CTD) whose complications can lead to management in the intensive care unit (ICU).

OBJECTIVES

To estimate by meta-analysis ICU mortality rates for CTD.

METHODS

A systematic literature review was performed to identify articles studying critically ill CTD patients. A random-effects model was chosen for analysis. Pooled proportion mortality was calculated using aggregated-data meta-analysis with a random-effects model and assessment of heterogeneity with the I² statistic. Risk of bias was assessed using the quality assessment tool.

RESULTS

Of the 5694 individual publications, a sample of 31 independent cohorts was used for the meta-analysis totalling 5007 patients. The main cause for admission was sepsis (43%) followed by "flare-ups" (40%). The overall pooled proportion of mortality of CTD patients across all 31 studies was 33% (95%CI: 28-38%). In the IIM subgroup and that of SSc, mortality was 70% (95%CI: 46-86%) and 40% (95%CI: 25-47%), respectively. In the SLE subgroup, mortality was similar to the overall pooled mortality of 35% (95%CI: 29-42%). Subgroup mortality for RA and pSS patients was respectively 20% (95%CI: 11-33%) and 17% (95%CI: 6-41%); lower than the overall pooled mortality. Heterogeneity in each subgroup remained high.

CONCLUSION

The overall pooled proportion of mortality of ICU patients with CTD was 33% (95%CI: 28-38%), with a high heterogeneity (I²= 89%). In the subgroup analysis, mortality was higher for patients with IIM and SSc.

[Severe SARS-CoV-2 infection: Clinical assessment and biomechanical functional evaluation one month after hospital discharge]

OBJECTIVE

To describe by an observational cross-sectional study the clinical and functional situation, at one month after hospital discharge, of patients admitted with COVID-19 in the hospital ICU between March and December 2020.

MATERIAL AND METHODS

59 patients were studied using different clinical scales and biomechanical analysis tests (hand dynamometry, fall risk assessment, gait and balance analysis).

RESULTS

At one month after discharge, patients reported persistent symptoms: dyspnea (47.5%), arthromyalgia (45%) and cough (22%). In the EQ-5D-5L questionnaire up to 73% of patients reported levels of anxiety or depression. 74.6% and 69.5% presented alterations in the strength of the right and left hand, respectively. The risk of falls in 38% of patients was moderate to very high. The somatosensory index remained within normal parameters, while the vestibular and, to a lesser extent, the visual indexes were altered. In gait, 81.4% of patients showed no abnormalities outside the normal range, with a normal average walking speed.

CONCLUSIONS

In the short term after severe COVID-19, patients have persistent symptomatology, anxiety/depression, impaired balance with increased risk of falls and loss of grip strength in both hands.

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.

High-dose intravenous immunoglobulins as a therapeutic option in critical illness polyneuropathy accompanying SARS-CoV-2 infection: A case-based review of the literature (Review)

The still ongoing COVID-19 pandemic has exposed the medical community to a number of major challenges. A significant number of patients require admission to intensive care unit (ICU) services due to severe respiratory, thrombotic and septic complications and require long-term hospitalization. Neuromuscular weakness is a common complication in critically ill patients who are treated in ICUs and are mechanically ventilated. This complication is frequently caused by critical illness myopathy (CIM) or critical illness polyneuropathy (CIP) and leads to difficulty in weaning from the ventilator. It is thought to represent an important neurologic manifestation of the systemic inflammatory response syndrome (SIRS). COVID-19 infection is known to trigger strong immune dysregulation, with an intense cytokine storm, as a result, the frequency of CIP is expected to be higher in this setting. The mainstay in the diagnosis of this entity beside the high level of clinical awareness is the electrophysiological examination that provides evidence of axonal motor and sensory polyneuropathy. The present article presents the case of a 54-year-old woman with severe COVID 19 infection who developed neuromuscular weakness, which turned out to be secondary to CIP and was treated successfully with a high dose of human intravenous immunoglobulins. Related to this case, we reviewed the relevant literature data regarding the epidemiology, pathophysiology and clinical features of this important complication and discussed also the treatment options and prognosis.

Association Between SARS-CoV-2 Infection and Immune-Mediated Myopathy in Patients Who Have Died

Importance

Myalgia, increased levels of creatine kinase, and persistent muscle weakness have been reported in patients with COVID-19.

Objective

To study skeletal muscle and myocardial inflammation in patients with COVID-19 who had died.

Design, Setting, and Participants

This case-control autopsy series was conducted in a university hospital as a multidisciplinary postmortem investigation. Patients with COVID-19 or other critical illnesses who had died between March 2020 and February 2021 and on whom an autopsy was performed were included. Individuals for whom informed consent to autopsy was available and the postmortem interval was less than 6 days were randomly selected. Individuals who were infected with SARS-CoV-2 per polymerase chain reaction test results and had clinical features suggestive of COVID-19 were compared with individuals with negative SARS-CoV-2 polymerase chain reaction test results and an absence of clinical features suggestive of COVID-19.

Main Outcomes and Measures

Inflammation of skeletal muscle tissue was assessed by quantification of immune cell infiltrates, expression of major histocompatibility complex (MHC) class I and class II antigens on the sarcolemma, and a blinded evaluation on a visual analog scale ranging from absence of pathology to the most pronounced pathology. Inflammation of cardiac muscles was assessed by quantification of immune cell infiltrates.

Results

Forty-three patients with COVID-19 (median [interquartile range] age, 72 [16] years; 31 men [72%]) and 11 patients with diseases other than COVID-19 (median [interquartile range] age, 71 [5] years; 7 men [64%]) were included. Skeletal muscle samples from the patients who died with COVID-19 showed a higher overall pathology score (mean [SD], 3.4 [1.8] vs 1.5 [1.0]; 95% CI, 0-3; P < .001) and a higher inflammation score (mean [SD], 3.5 [2.1] vs 1.0 [0.6]; 95% CI, 0-4; P < .001). Relevant expression of MHC class I antigens on the sarcolemma was present in 23 of 42 specimens from patients with COVID-19 (55%) and upregulation of MHC class II antigens in 7 of 42 specimens from patients with COVID-19 (17%), but neither were found in any of the controls. Increased numbers of natural killer cells (median [interquartile range], 8 [8] vs 3 [4] cells per 10 high-power fields; 95% CI, 1-10 cells per 10 high-power fields; P < .001) were found. Skeletal muscles showed more inflammatory features than cardiac muscles, and inflammation was most pronounced in patients with COVID-19 with chronic courses. In some muscle specimens, SARS-CoV-2 RNA was detected by reverse transcription-polymerase chain reaction, but no evidence for a direct viral infection of myofibers was found by immunohistochemistry and electron microscopy.

Conclusions and Relevance

In this case-control study of patients who had died with and without COVID-19, most individuals with severe COVID-19 showed signs of myositis ranging from mild to severe. Inflammation of skeletal muscles was associated with the duration of illness and was more pronounced than cardiac inflammation. Detection of viral load was low or negative in most skeletal and cardiac muscles and probably attributable to circulating viral RNA rather than genuine infection of myocytes. This suggests that SARS-CoV-2 may be associated with a postinfectious, immune-mediated myopathy.

ATTR amyloidosis during the COVID-19 pandemic: insights from a global medical roundtable

BACKGROUND

The global spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causing the ongoing coronavirus disease 2019 (COVID-19) pandemic has raised serious concern for patients with chronic disease. A correlation has been identified between the severity of COVID-19 and a patient's preexisting comorbidities. Although COVID-19 primarily involves the respiratory system, dysfunction in multiple organ systems is common, particularly in the cardiovascular, gastrointestinal, immune, renal, and nervous systems. Patients with amyloid transthyretin (ATTR) amyloidosis represent a population particularly vulnerable to COVID-19 morbidity due to the multisystem nature of ATTR amyloidosis.

MAIN BODY

ATTR amyloidosis is a clinically heterogeneous progressive disease, resulting from the accumulation of amyloid fibrils in various organs and tissues. Amyloid deposition causes multisystem clinical manifestations, including cardiomyopathy and polyneuropathy, along with gastrointestinal symptoms and renal dysfunction. Given the potential for exacerbation of organ dysfunction, physicians note possible unique challenges in the management of patients with ATTR amyloidosis who develop multiorgan complications from COVID-19. While the interplay between COVID-19 and ATTR amyloidosis is still being evaluated, physicians should consider that the heightened susceptibility of patients with ATTR amyloidosis to multiorgan complications might increase their risk for poor outcomes with COVID-19.

CONCLUSION

Patients with ATTR amyloidosis are suspected to have a higher risk of morbidity and mortality due to age and underlying ATTR amyloidosis-related organ dysfunction. While further research is needed to characterize this risk and management implications, ATTR amyloidosis patients might require specialized management if they develop COVID-19. The risks of delaying diagnosis or interrupting treatment for patients with ATTR amyloidosis should be balanced with the risk of exposure in the health care setting. Both physicians and patients must adapt to a new construct for care during and possibly after the pandemic to ensure optimal health for patients with ATTR amyloidosis, minimizing treatment interruptions.

Intensive Care and Treatment of Severe Guillain-Barré Syndrome

Guillain-Barré syndrome (GBS) is an acute polyneuropathy mostly characterized by acute flaccid paralysis with or without sensory/autonomous nerve dysfunction. Current immuno therapies including intravenous immunoglobulin (IVIg), plasma exchange (PE), and newly developed biological drugs benefit patients by alleviating hyperreactive immune responses. Up to 30% of patients develop respiratory failure during hospitalization and require mechanical ventilation and intensive care. Immunotherapies, mechanical ventilation, supportive care, and complication management during the intensive care unit (ICU) stay are equally emphasized. The most important aspect of intensive care and treatment of severe GBS, that is, mechanical ventilation, has been extensively reviewed elsewhere. In contrast to immunotherapies, care and treatment of GBS in the ICU setting are largely empirical. In this review, we intend to stress the importance of intensive care and treatment, other than mechanical ventilation in patients with severe GBS. We summarize the up-to-date knowledge of pharmacological therapies and ICU management of patients with severe GBS. We aim to answer some key clinical questions related to the management of severe GBS patients including but not limited to: Is IVIg better than PE or vice versa? Whether combinations of immune therapies benefit more? How about the emerging therapies promising for GBS? When to perform tracheal intubation or tracheostomy? How to provide multidisciplinary supportive care for severe cases? How to avert life-threatening complications in severe cases?

Guillain-Barré syndrome spectrum associated with COVID-19: an up-to-date systematic review of 73 cases

Since coronavirus disease-2019 (COVID-19) outbreak in January 2020, several pieces of evidence suggested an association between the spectrum of Guillain-Barré syndrome (GBS) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Most findings were reported in the form of case reports or case series, whereas a comprehensive overview is still lacking. We conducted a systematic review and searched for all published cases until July 20th 2020. We included 73 patients reported in 52 publications. A broad age range was affected (mean 55, min 11-max 94 years) with male predominance (68.5%). Most patients showed respiratory and/or systemic symptoms, and developed GBS manifestations after COVID-19. However, asymptomatic cases for COVID-19 were also described. The distributions of clinical variants and electrophysiological subtypes resemble those of classic GBS, with a higher prevalence of the classic sensorimotor form and the acute inflammatory demyelinating polyneuropathy, although rare variants like Miller Fisher syndrome were also reported. Cerebrospinal fluid (CSF) albuminocytological dissociation was present in around 71% cases, and CSF SARS-CoV-2 RNA was absent in all tested cases. More than 70% of patients showed a good prognosis, mostly after treatment with intravenous immunoglobulin. Patients with less favorable outcome were associated with a significantly older age in accordance with previous findings regarding both classic GBS and COVID-19. COVID-19-associated GBS seems to share most features of classic post-infectious GBS and possibly the same immune-mediated pathogenetic mechanisms. Nevertheless, more extensive epidemiological studies are needed to clarify these issues.

Mid-German Sepsis Cohort (MSC): a prospective observational study of sepsis survivorship

PURPOSE

The Mid-German Sepsis Cohort (MSC) aims to investigate mid-term and long-term functional disabilities in sepsis survivors from intensive care unit (ICU) discharge until 1 year after. Secondary, post-acute mortality and morbidity, health-related quality of life and healthcare utilisation will be investigated.

PARTICIPANTS

The MSC comprises adult (aged ≥18 years) patients who were treated for (severe) sepsis or septic shock on ICU. The participants were recruited between 15 April 2016 and 30 November 2018 from five German centres. Three thousand two hundred and ten patients with sepsis were identified, of which 1968 survived their ICU stay and were eligible for enrolment in the follow-up cohort. Informed consent for follow-up assessment was provided by 907 patients (46.1% of eligible patients).

FINDINGS TO DATE

The recruitment of the participants for follow-up assessments and the baseline data collection is completed. Incidence of sepsis was 116.7 patients per 1000 ICU patients. In this cohort profile, we provide an overview of the demographics and the clinical characteristics of both the overall sepsis cohort and the ICU survivors who provided informed consent for follow-up assessment (907 out of 1968 ICU survivors (46.1%)).

FUTURE PLANS

The follow-ups are conducted 3, 6 and 12 months after ICU discharge. Another yearly follow-up up to 5 years after ICU discharge is pursued. Several cooperation and satellite projects were initiated. This prospective cohort offers a unique resource for research on long-term sequelae of sepsis survivors.

TRIAL REGISTRATION NUMBER

German Clinical Trials Registry (DRKS00010050).

Single assessment of delirium severity during postacute intensive care of chronically critically ill patients and its associated factors: post hoc analysis of a prospective cohort study in Germany

OBJECTIVES

To assess the delirium severity (DS), its risk factors and association with adverse patient outcomes in chronically critically ill (CCI) patients.

DESIGN

A prospective cohort study.

SETTING

A tertiary care hospital with postacute intensive care units (ICUs) in Germany.

PARTICIPANTS

N=267 CCI patients with critical illness polyneuropathy and/or critical illness myopathy, aged 18-75 years, who had undergone elective tracheotomy for weaning failure.

INTERVENTIONS

None.

MEASURES

Primary outcomes: DS was assessed using the Confusion Assessment Method for the Intensive Care Unit-7 delirium severity score, within 4 weeks (t1) after the transfer to a tertiary care hospital. In post hoc analyses, univariate linear regressions were employed, examining the relationship of DS with clinical, sociodemographic and psychological variables. Secondary outcomes: additionally, correlations of DS with fatigue (using the Multidimensional Fatigue Inventory-20), quality of life (using the Euro-Quality of Life) and institutionalisation/mortality at 3 (t2) and 6 (t3) months follow-up were computed.

RESULTS

Of the N=267 patients analysed, 9.4% showed severe or most severe delirium symptoms. 4.1% had a full-syndromal delirium. DS was significantly associated with the severity of illness (p=0.016, 95% CI -0.1 to -0.3), number of medical comorbidities (p<0.001, 95% CI .1 to .3) and sepsis (p<0.001, 95% CI .3 to 1.0). Patients with a higher DS at postacute ICU (t1), showed a higher mental fatigue at t2 (p=0.008, 95% CI .13 to .37) and an increased risk for institutionalisation/mortality (p=0.043, 95% CI 1.1 to 28.9/p=0.015, 95% CI 1.5 to 43.2).

CONCLUSIONS

Illness severity is positively associated with DS during postacute care in CCI patients. An adequate management of delirium is essential in order to mitigate functional and cognitive long-term sequelae following ICU.

TRIAL REGISTRATION NUMBER

DRKS00003386.

Beatmung bei neuromuskulären Erkrankungen

Neuromuskuläre Erkrankungen betreffen das erste und zweite Motoneuron, die peripheren Nerven, die neuromuskulären Übertragung und die Muskelzelle. Es handelt sich um eine heterogene Gruppe von erblichen, degenerativen und autoimmunen Erkrankungen. Eine korrekte diagnostische Einordnung ist erforderlich, da zentralnervöse, kardiale, endokrine und weitere Begleitsymptome vorliegen können und für einige Erkrankungen bereits medikamentöse Therapien zur Verfügung stehen. Neuromuskuläre Erkrankungen haben eine große Bedeutung in der neuromuskulären Beatmungsmedizin. Die respiratorische Symptomatik resultiert in der Regel aus Paresen der am Atmen, Schlucken oder Husten beteiligten Muskulatur mit konsekutiver ventilatorischer Insuffienz, Dysphagie bis hin zur Speichelaspiration und Sekretretention. Mittels eines strukturierte Sekretmanagements und einer effektive nichtinvasive oder invasive Beatmungstherapie können neuromuskuläre Patienten viele Jahre mit guter Lebensqualität überleben. Themen dieses Kapitels sind ein Überblick über die neuromuskulären Erkrankungen, die Indikationen und Strategien der nichtinvasiven und der invasiven Beatmung und eine ausführliche Darstellung beatmungsmedizinisch besonders relevanter neuromuskulärer Erkrankungen wie der amyotrophe Lateralsklerose, des Guillain-Barré-Syndroms, der Myasthenia gravis und der Critical-Illness-Polyneuropathie/-Myopathie.

Guillain-Barré Syndrome

PURPOSE OF REVIEW

This article reviews the current state of Guillain-Barré syndrome (GBS), including its clinical presentation, evaluation, pathophysiology, and treatment.

RECENT FINDINGS

GBS is an acute/subacute-onset polyradiculoneuropathy typically presenting with sensory symptoms and weakness over several days, often leading to quadriparesis. Approximately 70% of patients report a recent preceding upper or lower respiratory tract infection or gastrointestinal illness. Approximately 30% of patients require intubation and ventilation because of respiratory failure. Nerve conduction studies in the acute inflammatory demyelinating polyradiculoneuropathy (AIDP) form of GBS typically show evidence for a multifocal demyelinating process, including conduction block or temporal dispersion in motor nerves. Sural sparing is a common phenomenon when testing sensory nerves. CSF analysis commonly shows an elevated protein, but this elevation may not be present until the third week of the illness. Patients with AIDP are treated with best medical management and either IV immunoglobulin (IVIg) or plasma exchange.

SUMMARY

GBS is a common form of acute quadriparesis; a high level of suspicion is needed for early diagnosis. With appropriate therapy, most patients make a very good to complete recovery.

Predictors of Major Depressive Disorder following Intensive Care of Chronically Critically Ill Patients

OBJECTIVE

Major depressive disorder (MDD) is a common condition following treatment in the Intensive Care Unit (ICU). Long-term data on MDD in chronically critically ill (CCI) patients are scarce. Hence, the primary aim of the present study was to investigate the frequency and predictors of MDD after intensive care of CCI patients.

MATERIALS AND METHODS

In a prospective cohort study, patients with long-term mechanical ventilation requirements (n=131) were assessed with respect to a diagnosis of MDD, using the Structured Clinical Interview for DSM-IV, three and six months after the transfer from acute ICU to post-acute ICU. Sociodemographic, psychological, and clinical risk factors with p values ≤ 0.1 were identified in a univariate logistic regression analysis and entered in a multivariable logistic regression model. A mediator analysis was run using the bootstrapping method, testing the mediating effect of perceived helplessness during the ICU stay, between the recalled traumatic experience from the ICU and a post-ICU MDD.

RESULTS

17.6% (n=23) of the patients showed a full- or subsyndromal MDD. Perceived helplessness, recalled experiences of a traumatic event from the ICU, symptoms of acute stress disorder, and the diagnosis of posttraumatic stress disorder (PTSD) after ICU could be identified as significant predictors of MDD. In a mediator analysis, perceived helplessness could be proved as a mediator.

CONCLUSIONS

Every fifth CCI patient suffers from MDD up to six months after being discharged from ICU. Particularly, perceived helplessness during the ICU stay seems to mainly affect the long-term evolvement of MDD. CCI patients with symptoms of acute stress disorder/PTSD should also be screened for MDD.

Risk Factors of Delayed Onset Posttraumatic Stress Disorder in Chronically Critically Ill Patients

The main aim of this study was to investigate factors associated with a delayed-onset posttraumatic stress disorder (PTSD) after the intensive care unit (ICU) treatment of patients with a chronic critical illness (CCI). Patients (n = 97) with critical illness polyneuropathy or critical illness myopathy were interviewed via the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, 4th Edition. The diagnosis of the acute stress disorder was assessed within 1 month (t1), the diagnosis of PTSD at 3 (t2) and 6 (t3) months after transfer from the acute care ICU to the post-acute ICU. Patients showing a delayed-onset or persistent course of PTSD were subsumed in one group; 24.7% (n = 24) showed a delayed-onset PTSD. Significant risk factors were as follows: the severity of the medical illness, the perceived fear of dying at the ICU, the number of traumatic memories from the ICU, and the presence of a coronary heart disease. Every fourth patient with CCI showed a delayed-onset PTSD up to 6 months after the ICU treatment. Markers for a delayed-onset PTSD should already be assessed at the time of discharge from the ICU.

[Critical illness polyneuropathy and myopathy as neurological complications of sepsis]

Intensive care unit acquired weakness (ICUAW) is a frequent and severe complication of intensive care management. Within ICUAW critical illness polyneuropathy (CIP) and myopathy (CIM) can be differentiated. The major symptom of ICUAW is progressive quadriparesis, which makes weaning from the respirator more difficult, can appear early after admission to an ICU and can often be detected several months after discharge from the ICU. The pathophysiology of ICUAW is multifactorial and complex. Potential therapeutic approaches are the early and sufficient therapy of mulitorgan dysfunction, optimal control of glucose levels as well as early and intensive physiotherapy. This review article discusses the data on incidence, pathophysiology, diagnostic approaches and prognosis of ICUAW.

Survivors of intensive care with type 2 diabetes and the effect of shared care follow-up clinics: study protocol for the SWEET-AS randomised controlled feasibility study

BACKGROUND

Many patients who survive the intensive care unit (ICU) experience long-term complications such as peripheral neuropathy and nephropathy which represent a major source of morbidity and affect quality of life adversely. Similar pathophysiological processes occur frequently in ambulant patients with diabetes mellitus who have never been critically ill. Some 25 % of all adult ICU patients have diabetes, and it is plausible that ICU survivors with co-existing diabetes are at heightened risk of sequelae from their critical illness. ICU follow-up clinics are being progressively implemented based on the concept that interventions provided in these clinics will alleviate the burdens of survivorship. However, there is only limited information about their outcomes. The few existing studies have utilised the expertise of healthcare professionals primarily trained in intensive care and evaluated heterogenous cohorts. A shared care model with an intensivist- and diabetologist-led clinic for ICU survivors with type 2 diabetes represents a novel targeted approach that has not been evaluated previously. Prior to undertaking any definitive study, it is essential to establish the feasibility of this intervention.

METHODS

This will be a prospective, randomised, parallel, open-label feasibility study. Eligible patients will be approached before ICU discharge and randomised to the intervention (attending a shared care follow-up clinic 1 month after hospital discharge) or standard care. At each clinic visit, patients will be assessed independently by both an intensivist and a diabetologist who will provide screening and targeted interventions. Six months after discharge, all patients will be assessed by blinded assessors for glycated haemoglobin, peripheral neuropathy, cardiovascular autonomic neuropathy, nephropathy, quality of life, frailty, employment and healthcare utilisation. The primary outcome of this study will be the recruitment and retention at 6 months of all eligible patients.

DISCUSSION

This study will provide preliminary data about the potential effects of critical illness on chronic glucose metabolism, the prevalence of microvascular complications, and the impact on healthcare utilisation and quality of life in intensive care survivors with type 2 diabetes. If feasibility is established and point estimates are indicative of benefit, funding will be sought for a larger, multi-centre study.

TRIAL REGISTRATION

ANZCTR ACTRN12616000206426.

Impaired Ca(2+) release contributes to muscle weakness in a rat model of critical illness myopathy

BACKGROUND

Critical illness myopathy is an acquired skeletal muscle disorder with severe myosin loss and muscle weakness frequently seen in intensive care unit (ICU) patients. It is unknown if impaired excitation-contraction coupling contributes to the muscle weakness.

METHODS

We used a unique ICU model where rats were deeply sedated, post-synaptically pharmacologically paralyzed, mechanically ventilated and closely monitored for up to ten days. Single intact fibers from the flexor digitorum brevis muscle were isolated and used to measure force and free myoplasmic [Ca(2+)] ([Ca(2+)]i) during tetanic contractions.

RESULTS

Fibers from ICU rats had 80 % lower tetanic [Ca(2+)]i and produced only 15 % of the force seen in fibers from sham-operated (SHAM) rats. In the presence of 5 mM caffeine, tetanic [Ca(2+)]i was similar in fibers from ICU and SHAM rats but force was 50 % lower in fibers from ICU rats than SHAM rats. Confocal imaging showed disrupted tetanic [Ca(2+)]i transients in fibers from ICU rats compared to SHAM rats. Western blots showed similar levels of Na(+) channel and dihydropyridine receptor (DHPR) protein expression, whereas ryanodine receptor (RyR) and sarco-endoplasmic reticulum Ca(2+) ATPase 1 (SERCA1) expression was markedly lower in muscle of ICU rats than in SHAM rats. Immunohistochemical analysis showed that distribution of Na(+) channel and DHPR protein on the sarcolemma was disrupted in fibers from ICU rats compared with SHAM rats.

CONCLUSIONS

These results suggest that impaired SR Ca(2+) release contributes to the muscle weakness seen in patients in ICU.

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.

Neurology of Sepsis

Sepsis is a systemic inflammatory response syndrome occurring secondary to infection and labeled severe when end organ dysfunction or tissue hypoperfusion transpires. Sepsis-associated mortality remains high among critically ill patients, with chronic disease and immunosuppression being the most common risk factors. Studies demonstrate that early recognition and treatment are vital to decreasing mortality. Some of the least understood effects of sepsis are the associated neurologic complications. The peripheral nervous system (PNS) has gained most consideration and thought, largely due to dependence on mechanical ventilation. Central nervous system (CNS) complications related to sepsis have only more recently gained attention but continue to go unnoticed. Aside from the clinical examination, electroencephalography (EEG) is a sensitive tool for prognostication or uncovering non-convulsive seizures in encephalopathic patients. Further studies are needed to further define the urgency of a prevention and treatment plan for the deleterious effects of sepsis on the PNS and CNS.

Onset of reversible flaccid quadriplegia during treatment of thyrotoxic crisis

Two unrelated women were hospitalized for thyrotoxic crisis complicated by multiple organ failure. Both patients were treated with antithyroid drugs and hydrocortisone, as well as insulin for hyperglycemia, and underwent mechanical ventilation with sedation. Flaccid quadriplegia became apparent after each patient completely recovered their level of consciousness once sedation was discontinued on days 6 and 15, respectively. Three to six months of rehabilitation was required for the muscle strength to fully improve in both cases. Thyrotoxicosis in addition to critical illness polyneuromyopathy and the administration of glucocorticoid therapy may have contributed to the onset of quadriplegia in these two cases. Flaccid quadriplegia is one of the serious neuromuscular conditions experienced during the treatment of thyrotoxic crisis.

[Intensive care unit acquired weakness. Pathogenesis, treatment, rehabilitation and outcome]

The diagnosis of intensive care unit acquired weakness (ICUAW) in the setting of neurological rehabilitation is steadily increasing. This is due to the fact that the intensive care of patients with sepsis or after cardiac or abdominal surgery is improving. A longer duration of respiratory weaning and comorbidities frequently complicate rehabilitation. Clinically, patients present with a flaccid (tetra) paresis and electrophysiological studies have shown axonal damage. Besides involvement of peripheral nerves, muscle can also be affected (critical illness myopathy) leading to ICUAW with inconstant myopathic damage patterns found by electrophysiological testing. Mixed forms can also be found. A specific therapy for ICUAW is not available. Early mobilization to be initiated on the intensive care unit and commencing neurological rehabilitation improve the outcome of ICUAW. This review highlights the current literature regarding the etiology and diagnosis of ICUAW. Furthermore, studies about rehabilitation and outcome of ICUAW are discussed.

Critical illness polyneuropathy and myopathy: a systematic review

Critical illness polyneuropathy and critical illness myopathy are frequent complications of severe illness that involve sensorimotor axons and skeletal muscles, respectively. Clinically, they manifest as limb and respiratory muscle weakness. Critical illness polyneuropathy/myopathy in isolation or combination increases intensive care unit morbidity via the inability or difficulty in weaning these patients off mechanical ventilation. Many patients continue to suffer from decreased exercise capacity and compromised quality of life for months to years after the acute event. Substantial progress has been made lately in the understanding of the pathophysiology of critical illness polyneuropathy and myopathy. Clinical and ancillary test results should be carefully interpreted to differentiate critical illness polyneuropathy/myopathy from similar weaknesses in this patient population. The present review is aimed at providing the latest knowledge concerning the pathophysiology of critical illness polyneuropathy/myopathy along with relevant clinical, diagnostic, differentiating, and treatment information for this debilitating neurological disease.

Acute and long-term dysphagia in critically ill patients with severe sepsis: results of a prospective controlled observational study

Dysphagia is a major risk factor for morbidity and mortality in critically ill patients treated in intensive care units (ICUs). Structured otorhinolaryngological data on dysphagia in ICU survivors with severe sepsis are missing. In a prospective study, 30 ICU patients with severe sepsis and thirty without sepsis as control group were examined using bedside fiberoptic endoscopic evaluation of swallowing after 14 days in the ICU (T1) and 4 months after onset of critical illness (T2). Swallowing dysfunction was assessed using the Penetration-Aspiration Scale (PAS). The Functional Oral Intake Scale was applied to evaluate the diet needed. Primary endpoint was the burden of dysphagia defined as PAS score >5. At T1, 19 of 30 severe sepsis patients showed aspiration with a PAS score >5, compared to 7 of 30 in critically ill patients without severe sepsis (p = 0.002). Severe sepsis and tracheostomy were independent risk factors for severe dysphagia with aspiration (PAS > 5) at T1 (p = 0.042 and 0.006, respectively). 4-month mortality (T2) was 57 % in severe sepsis patients compared to 20 % in patients without severe sepsis (p = 0.006). At T2, more severe sepsis survivors were tracheostomy-dependent and needed more often tube or parenteral feeding (p = 0.014 and p = 0.040, respectively). Multivariate analysis revealed tracheostomy at T1 as independent risk factor for severe dysphagia at T2 (p = 0.030). Severe sepsis appears to be a relevant risk factor for long-term dysphagia. An otorhinolaryngological evaluation of dysphagia at ICU discharge is mandatory for survivors of severe critical illness to plan specific swallowing rehabilitation programs.

Intensive care unit acquired weakness in children: Critical illness polyneuropathy and myopathy

BACKGROUND AND AIMS

Intensive care unit acquired weakness (ICUAW) is a common occurrence in patients who are critically ill. It is most often due to critical illness polyneuropathy (CIP) or to critical illness myopathy (CIM). ICUAW is increasingly being recognized partly as a consequence of improved survival in patients with severe sepsis and multi-organ failure, partly related to commonly used agents such as steroids and muscle relaxants. There have been occasional reports of CIP and CIM in children, but little is known about their prevalence or clinical impact in the pediatric population. This review summarizes the current understanding of pathophysiology, clinical presentation, diagnosis and treatment of CIP and CIM in general with special reference to published literature in the pediatric age group.

SUBJECTS AND METHODS

Studies were identified through MedLine and Embase using relevant MeSH and Key words. Both adult and pediatric studies were included.

RESULTS

ICUAW in children is a poorly described entity with unknown incidence, etiology and unclear long-term prognosis.

CONCLUSIONS

Critical illness polyneuropathy and myopathy is relatively rare, but clinically significant sequelae of multifactorial origin affecting morbidity, length of intensive care unit (ICU) stay and possibly mortality in critically ill children admitted to pediatric ICU.

Exercise limitation following transplantation

Organ transplantation is one of the medical miracles or the 20th century. It has the capacity to substantially improve exercise performance and quality of life in patients who are severely limited with chronic organ failure. We focus on the most commonly performed solid-organ transplants and describe peak exercise performance following recovery from transplantation. Across all of the common transplants, evaluated significant reduction in VO2peak is seen (typically renal and liver 65%-80% with heart and/or lung 50%-60% of predicted). Those with the lowest VO2peak pretransplant have the lowest VO2peak posttransplant. Overall very few patients have a VO2peak in the normal range. Investigation of the cause of the reduction of VO2peak has identified many factors pre- and posttransplant that may contribute. These include organ-specific factors in the otherwise well-functioning allograft (e.g., chronotropic incompetence in heart transplantation) as well as allograft dysfunction itself (e.g., chronic lung allograft dysfunction). However, looking across all transplants, a pattern emerges. A low muscle mass with qualitative change in large exercising skeletal muscle groups is seen pretransplant. Many factor posttransplant aggravate these changes or prevent them recovering, especially calcineurin antagonist drugs which are key immunosuppressing agents. This results in the reduction of VO2peak despite restoration of near normal function of the initially failing organ system. As such organ transplantation has provided an experiment of nature that has focused our attention on an important confounder of chronic organ failure-skeletal muscle dysfunction.

Impairment of small somatic and autonomic nerve fibres in intensive care unit patients with severe sepsis and critical illness polyneuropathy--a single center controlled observational study

Background

Axonal damage in large myelinated nerve fibres occurs in about 70% of patients with severe sepsis, known as critical illness polyneuropathy and contributes significantly to an increased short- and long-term morbidity and mortality in this population. Among other pathophysiological mechanisms, autonomic dysregulation, characterized by high concentrations of circulating catecholamines in the presence of impaired sympathetic modulation of heart and vessels have been discussed. We hypothesize that autonomic small fibre neuropathy play an important role in autonomic failure.

Methods/Design

Single center, non-randomized, controlled, observational study. Skin biopsies of patients with severe sepsis and/or septic shock are compared with those of age-matched controls. In order to assess impairment of small nerve fibres, skin biopsies are taken at onset of severe sepsis, and two and 16 weeks later. Intraepidermal nerve fibre densities are histologically analyzed using anti protein gene product (PGP) 9.5 immunostaining. In addition, standardized clinical examinations, as Medical Research Council (MRC) scores of muscle strength, Rankin scores, and standardized nerve conduction studies of the right median nerve, the right tibial nerve, the left fibular nerve, and both sural nerves are performed, to identify critical illness polyneuropathy and to neurophysiologically quantify the damage of large nerve fibres.

Discussion

The study will allow to describe the frequency of small fibre neuropathy in patients with severe sepsis up to four months after onset of severe sepsis and to evaluate its relationship to critical illness polyneuropathy.

Trial registration

The trial has been registered to the German Clinical Trials Register. The trial registration number is DRKS-ID: DRKS00000642.

Muscle ultrasound for early assessment of critical illness neuromyopathy in severe sepsis

INTRODUCTION

Muscle ultrasound is emerging as a promising tool in the diagnosis of neuromuscular diseases. The current observational study evaluates the usefulness of muscle ultrasound in patients with severe sepsis for assessment of critical illness polyneuropathy and myopathy (CINM) in the intensive care unit.

METHODS

28 patients with either septic shock or severe sepsis underwent clinical neurological examinations, muscle ultrasound, and nerve conduction studies on days 4 and 14 after onset of sepsis. 26 healthy controls of comparable age underwent clinical neurological evaluation and muscle ultrasound only.

RESULTS

26 of the 28 patients exhibited classic electrophysiological characteristics of CINM, and all showed typical clinical signs. Ultrasonic echogenicity of muscles was graded semiquantitatively and fasciculations were evaluated in muscles of proximal and distal arms and legs. 75% of patients showed a mean echotexture greater than 1.5, which was the maximal value found in the control group. A significant difference in mean muscle echotexture between patients and controls was found at day 4 and day 14 (both p < 0.001). In addition, from day 4 to day 14, the mean grades of muscle echotexture increased in the patient group, although the values did not reach significance levels (p = 0.085). Controls revealed the lowest number of fasciculations. In the patients group, fasciculations were detected in more muscular regions (lower and upper arm and leg) in comparison to controls (p = 0.08 at day 4 and p = 0.002 at day 14).

CONCLUSIONS

Muscle ultrasound represents an easily applicable, non-invasive diagnostic tool which adds to neurophysiological testing information regarding morphological changes of muscles early in the course of sepsis. Muscle ultrasound could be useful for screening purposes prior to subjecting patients to more invasive techniques such as electromyography and/or muscle biopsy.

TRIAL REGISTRATION

German Clinical Trials Register, DRKS-ID: DRKS00000642.

Early treatment with IgM-enriched intravenous immunoglobulin does not mitigate critical illness polyneuropathy and/or myopathy in patients with multiple organ failure and SIRS/sepsis: a prospective, randomized, placebo-controlled, double-blinded trial

Introduction

Critical illness polyneuropathy and/or myopathy (CIPNM) is a severe complication of critical illness. Retrospective data suggest that early application of IgM-enriched intravenous immunoglobulin (IVIG) may prevent or mitigate CIPNM. Therefore, the primary objective was to assess the effect of early IgM-enriched IVIG versus placebo to mitigate CIPNM in a prospective setting.

Methods

In this prospective, randomized, double-blinded and placebo-controlled trial, 38 critically ill patients with multiple organ failure (MOF), systemic inflammatory response syndrome (SIRS)/sepsis, and early clinical signs of CIPNM were included. Patients were randomly assigned to be treated either with IgM-enriched IVIG or placebo over a period of three days. CIPNM was measured by the CIPNM severity sum score based on electrophysiological stimulation of the median, ulnar, and tibial nerves on days 0, 4, 7, 14 and on the histological evaluation of muscle biopsies on days 0 and 14 and ranged from 0 (no CIPNM) to 8 (very severe CIPNM).

Results

A total of 38 critically ill patients were included and randomized to receive either IgM-enriched IVIG (n = 19) or placebo (n = 19). Baseline characteristics were similar between the two groups. CIPNM could not be improved by IVIG treatment, represented by similar CIPNM severity sum scores on day 14 (IVIG vs. placebo: 4.8 ± 2.0 vs. 4.5 ± 1.8; P = 0.70). CIPNM severity sum score significantly increased from baseline to day 14 (3.5 ± 1.6 vs. 4.6 ± 1.9; P = 0.002). After an interim analysis the study was terminated early due to futility in reaching the primary endpoint.

Conclusions

Early treatment with IVIG did not mitigate CIPNM in critically ill patients with MOF and SIRS/sepsis.

Trial registration

Clinicaltrials.gov: NCT01867645

Elderly persons with ICU-acquired weakness: the potential role for β-hydroxy-β-methylbutyrate (HMB) supplementation?

Intensive care unit (ICU)-acquired weakness is common and characterized by muscle loss, weakness, and paralysis. It is associated with poor short-term outcomes, including increased mortality, but the consequences of reduced long-term outcomes, including decreased physical function and quality of life, can be just as devastating. ICU-acquired weakness is particularly relevant to elderly patients who are increasingly consuming ICU resources and are at increased risk for ICU-acquired weakness and complications, including mortality. Elderly patients often enter critical illness with reduced muscle mass and function and are also at increased risk for accelerated disuse atrophy with acute illness. Increasingly, intensivists and researchers are focusing on strategies and therapies aimed at improving long-term neuromuscular function. β-Hydroxy-β-methylbutyrate (HMB), an ergogenic supplement, has shown efficacy in elderly patients and certain clinical populations in counteracting muscle loss. The present review discusses ICU-acquired weakness, as well as the unique physiology of muscle loss and skeletal muscle function in elderly patients, and then summarizes the evidence for HMB in elderly patients and in clinical populations. We subsequently postulate on the potential role and strategies in studying HMB in elderly ICU patients to improve muscle mass and function.

Early Physical Rehabilitation in the ICU: A Review for the Neurohospitalist

Advances in critical care have resulted in improved intensive care unit (ICU) mortality. However, improved ICU survival has resulted in a growing number of ICU survivors living with long-term sequelae of critical illness, such as impaired physical function and quality of life (QOL). In addition to critical illness, prolonged bed rest and immobility may lead to severe physical deconditioning and loss of muscle mass and muscle weakness. ICU-acquired weakness is associated with increased duration of mechanical ventilation and weaning, longer ICU and hospital stay, and increased mortality. These physical impairments may last for years after ICU discharge. Early Physical Medicine and Rehabilitation (PM&R) interventions in the ICU may attenuate or prevent the weakness and physical impairments occurring during critical illness. This article reviews the evidence regarding safety, feasibility, barriers, and benefits of early PM&R interventions in ICU patients and discusses the limited existing data on early PM&R in the neurological ICU and future directions for early PM&R in the ICU.

Reversible tetraplegia after percutaneous nephrostolithotomy and septic shock: a case of critical illness polyneuropathy and myopathy with acute onset and complete recovery

Background

Critical illness polyneuropathy (CIP) and critical illness myopathy (CIM) are complications causing weakness of respiratory and limb muscles in critically ill patients. As an important differential diagnosis of Guillain-Barré syndrome (GBS), CIP and CIM should be diagnosed with caution, after a complete clinical and laboratory examination. Although not uncommon in ICU, CIP and CIM as severe complications of percutaneous nephrostolithotomy (PNL) have not been documented in literature.

Case presentation

A 48-year-old Chinese woman was referred to our hospital, complaining of occasional pain in the right lower back for one month. Lithiasis was diagnosed by ultrasonographical and radiological examinations on the urinary system. PNL was indicated and performed. The patient developed CIP and CIM on the fourth day after PNL. Early recognition and treatment of the severe complications contributed to a satisfactory recovery of the patient.

Conclusion

This case expands our understanding of the complications of PNL and underscores the importance of differentiating CIP/CIM from GBS in case of such patients developing weakness after the treatment. Clinical characteristics and examination results should be carefully evaluated to make the diagnosis of CIP or CIM. Both anti-septic prophylaxis and control of hyperglycemia might be effective for the prevention of CIP or CIM; aggressive treatment on sepsis and multiple organ failure is considered to be the most effective measure to reduce the incidence of CIP/CIM.

ICU-acquired weakness: mechanisms of disability

PURPOSE OF REVIEW

ICU-acquired weakness (ICUAW) is now recognized as a major complication of critical illness. There is no doubt that ICUAW is prevalent - some might argue ubiquitous - after critical illness, but its true role, the interaction with preexisting nerve and muscle lesions as well as its contribution to long-term functional disability, remains to be elucidated.

RECENT FINDINGS

In this article, we review the current state-of-the-art of the basic pathophysiology of nerve and muscle weakness after critical illness and explore the current literature on ICUAW with a special emphasis on the most important mechanisms of weakness.

SUMMARY

Variable contributions of structural and functional changes likely contribute to both early and late myopathy and neuropathy, although the specifics of the temporality of both processes, and the influence patient comorbidities, age, and nature of the ICU insult have on them, remain to be determined.

[Electromyography (EMG) and neurography in patients with severe neuromuscular diseases]

BACKGROUND

Many neuromuscular diseases are potentially severe, and EMG and neurography are methods used in the assessment of these conditions.

METHOD

The article is based on the authors' knowledge and experience, with special emphasis on the use of these methods in the assessment of severe diseases affecting striated muscle and peripheral nerves. A PubMed search was performed with the cut-off fifteen years back in time, and in addition a discretionary selection was made of articles known to the authors.

RESULTS

EMG is the most valuable method for assessing myopathy, and neurography provides most information about neuropathy, but the methods are complementary. These examinations are the most sensitive for diagnosing some conditions (for example myasthaenia) A high level of expertise is necessary for diagnosing these conditions.

INTERPRETATION

EMG and neurography are important and often necessary means of assessing patients with severe neuromuscular disease.

Peripheral neuropathy caused by severe hypothermia

OBJECTIVE

To report follow-up data in the evaluation of peripheral neuropathy in a 29-year old female after accidental deep hypothermia (13.7°C) in 1999.

METHODS

Nerve conduction studies (NCS) and electromyography (EMG) were performed 20 days after the accident and again after 5 months and 1, 3, 5 and 11 years. Macro EMG was performed after 3, 5 and 11 years. To evaluate small fiber function, RR-interval, sympathetic skin response, quantitative sensory testing and skin biopsy for quantification of intra-epidermal nerve fiber density were performed in 2009.

RESULTS

In the intensive care unit sensory and motor responses were absent except for the tibial nerves, and EMG showed profuse denervation. Improvement of amplitudes and conduction velocities was seen during the first 5 years. Muscular atrophy of hand muscles persisted. Large fibers were involved more extensively than small fibers.

CONCLUSIONS

A severe axonal sensorimotor polyneuropathy developed in the intensive care unit following severe hypothermia. The mechanism was most likely cold injury to peripheral nerves.

SIGNIFICANCE

The clinical picture and the laboratory findings indicate that even multi-organ dysfunction and, of specific interest in this study, a severe axonal degeneration may come to a good restitution after long time.

Intensive care unit-acquired weakness: implications for physical therapist management

Patients admitted to the intensive care unit (ICU) can develop a condition referred to as "ICU-acquired weakness." This condition is characterized by profound weakness that is greater than might be expected to result from prolonged bed rest. Intensive care unit-acquired weakness often is accompanied by dysfunction of multiple organ systems. Individuals with ICU-acquired weakness typically have significant activity limitations, often requiring physical assistance for even the most basic activities associated with bed mobility. Many of these individuals have activity limitations months to years after hospitalization. The purpose of this article is to review evidence that guides physical rehabilitation of people with ICU-acquired weakness. Included are diagnostic criteria, medical management, and prognostic indicators, as well as criteria for beginning physical rehabilitation, with an emphasis on patient safety. Data are presented indicating that rehabilitation can be implemented with very few adverse effects. Evidence is provided for appropriate measurement approaches and for physical intervention strategies. Finally, some of the key issues are summarized that should be investigated to determine the best intervention guidelines for individuals with ICU-acquired weakness.

[Critical illness polyneuropathy and critical illness myopathy]

Critical illness polyneuropathy (CIP) and critical illness myopathy (CIM) are frequent complications in critically ill patients and both are associated with sepsis, systemic inflammatory response syndrome (SIRS) and multiorgan failure. Major signs are muscle weakness and problems of weaning from the ventilator. Both CIP and CIM lead to elongated times of ventilation, elongated hospital stay, elongated times of rehabilitation and increased mortality. Electrophysiological measurements help to detect CIP and CIM early in the course of the disease. State of the art sepsis therapy is the major target to prevent the development of CIP and CIM. Although no specific therapy of CIP and CIM has been established in the past, the diagnosis generally improves the therapeutic management (weaning from the ventilator, early physiotherapy, etc.). This review provides an overview of clinical and diagnostic features of CIP and CIM and summarizes current pathophysiological and therapeutic concepts.