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

Nerve Echogenicity in Polyneuropathies of Various Etiologies-Results of a Retrospective Semi-Automatic Analysis of High-Resolution Ultrasound Images

Echogenicity of peripheral nerves in high-resolution ultrasound (HRUS) provides insight into the structural damage of peripheral nerves in various polyneuropathies. The aim of this study was to compare nerve echogenicity in different primarily axonal or demyelinating polyneuropathies to examine the significance of this parameter. Performing semi-automated echogenicity analysis and applying Image J, we retrospectively used HRUS images of 19 patients with critical illness polyneuropathy (CIP), and 27 patients with chemotherapy-induced polyneuropathy (CIN) and compared them to 20 patients with chronic inflammatory demyelinating polyneuropathy (CIDP). The fraction of black representing echogenicity was measured after converting the images into black and white. The nerves of patients with progressive CIDP significantly differed from the hyperechogenic nerves of patients with other polyneuropathies at the following sites: the median nerve at the forearm (p < 0.001), the median nerve at the upper arm (p < 0.004), and the ulnar nerve at the upper arm (p < 0.001). The other polyneuropathies showed no notable differences. Altogether, the comparison of echogenicity between different polyneuropathies supports the assumption that there are differences depending on the genesis of the structural nerve damage. However, these differences are slight, and cannot be used to show clear differences between each polyneuropathy form.

[Postextubation dysphagia in intensive care patients : Current findings and clinical recommendations]

BACKGROUND

A considerable number of critically ill and mechanically ventilated intensive care patients show pronounced dysphagia after extubation. Many studies have shown that postextubation dysphagia (PED) leads to a significant decline of outcome. The awareness, timely diagnostic procedures and integration of suitable treatment methods in intensive care units are therefore of great importance.

OBJECTIVE

Current basic findings on PED, diagnostic possibilities, therapeutic methods as well as the development of concrete recommendations for clinical practice.

METHODS

A selective literature search was performed in PubMed, Medline and Cochrane using keywords.

RESULTS

In the literature the incidence PED is reported very heterogeneous but is probably at least 10% in intensive care patients after mechanical ventilation. The duration of intubation plays a critical role here. A multifactorial interaction of several factors is assumed to be the cause, whereby the impairment of laryngeal structures is of particular relevance. A PED leads to longer hospital stays, higher mortality, more reintubation and a higher number of patients with tube feeding. With respect to diagnostics, screening by trained nurses, clinical swallowing examinations and, in particular, the use of instrumental examinations by flexible endoscopic evaluation of swallowing (FEES) are recommended. The treatment should include adaptive measures in the sense of an adapted diet but also functional exercises. Innovative approaches, such as electrical stimulation are also conceivable. The aim is primarily to avoid penetration and aspiration in order to counteract respiratory complications.

CONCLUSION

In many intensive care units the clinical picture of PED is still neglected despite clear evidence. A simple algorithm in the treatment of intensive care patients can contribute to early detection and initiation of further steps. These should be integrated into clinical treatment standards.

New Approaches to Critical Illness Polyneuromyopathy: High-Resolution Neuromuscular Ultrasound Characteristics and Cytokine Profiling

Background

Diagnosis of intensive care unit acquired weakness (ICUAW) is challenging. Pathogenesis of underlying critical illness polyneuromyopathy (CIPNM) remains incompletely understood. This exploratory study investigated whether longitudinal neuromuscular ultrasound examinations and cytokine analyses in correlation to classical clinical and electrophysiological assessment contribute to the understanding of CIPNM.

Methods

Intensive care unit patients were examined every 7 days until discharge from hospital. Clinical status, nerve conduction studies, electromyography as well as ultrasound of peripheral nerves and tibial anterior muscle were performed. Cytokine levels were analyzed by a bead-based multiplex assay system.

Results

Of 248 screened patients, 35 patients were included at median of 6 days (IQR: 8) after admission to intensive care unit. Axonal damage was the main feature of CIPNM. At the peak of CIPNM (7 days after inclusion), nerve ultrasound showed cross-sectional area increase of tibial nerve as a sign of inflammatory edema as well as hypoechoic nerves as a possible sign of inflammation. Cytokine analyses showed signs of monocyte and macrophage activation at this stage. Fourteen days after inclusion, cytokines indicated systemic immune response as well as profiles associated to neovascularization and regeneration.

Conclusions

Exploratory neuromuscular ultrasound and cytokine analyses showed signs of inflammation like macrophage and monocyte activation at the peak of CIPNM followed by a systemic immune response parallel to axonal damage. This underlines the role of both axonal damage and inflammation in pathogenesis of CIPNM.

Electronic supplementary material

The online version of this article (10.1007/s12028-020-01148-2) contains supplementary material, which is available to authorized users.

The Impact of Sepsis on the Outcomes of COPD Patients: A Population-Based Cohort Study

This study aims to identify the impact of new-onset sepsis in patients with chronic obstructive pulmonary disease (COPD) including the effects on acute exacerbations, pneumonia and mortality. Using the National Health Insurance Research Database of Taiwan, all patients with COPD older than 40 years between 1988 and 2010 were recruited. After propensity score matching, each of the 8774 COPD patients with and without sepsis were identified to have similar characteristics. The primary outcome was severe exacerbations of COPD, with a severe exacerbation being defined as a patient requiring hospital admission or an emergency department visit due to COPD. The secondary outcomes were pneumonia, serious pneumonia, and all-cause mortality. The post-index overall cumulative incidence rates of total acute exacerbations were 11.2/person-years in the sepsis group and 6.2/person-years in the non-sepsis group (adjusted hazard ratio (HR) = 1.38, 95% confidence interval (CI), 1.38⁻1.40). The sepsis group also had higher risks of severe exacerbations (adjusted HR = 2.05, 95% CI, 2.02⁻2.08), severe exacerbations requiring hospitalization (adjusted HR = 2.30, 95% CI, 2.24⁻2.36), and severe exacerbations leading to an emergency room visit (adjusted HR = 1.91, 95% CI, 1.87⁻1.94). Regarding the effect on secondary outcomes, the sepsis group had higher risks of mortality (incidence rate: 23.7/person-years vs. 11.34/person-years, adjusted HR = 2.27, 95% CI, 2.14⁻2.41), pneumonia (incidence rate: 26.41 per person-days vs. 10.34 per person-days, adjusted HR = 2.70, 95% CI, 2.5⁻2.91), and serious pneumonia (incidence rate: 5.84 per person-days vs. 1.98 per person-days, adjusted HR = 2.89, 95% CI, 2.5⁻3.33) compared with the non-sepsis group. Sepsis survivors among patients with COPD had a higher risk of severe exacerbations, pneumonia, serious pneumonia, and mortality compared to patients with COPD without sepsis.

[Critical illness myopathy and polyneuropathy]

An average of 50-80% of patients treated in the intensive care unit is affected by disturbances of neuromuscular functions due to damage to the nerves and muscles, which has led to the terms critical illness polyneuropathy and myopathy. Both components occur in 30-50% of patients, while the others predominantly show a pure myopathy, while pure neuropathy is rare. Meanwhile, the descriptive term of the concept as intensive care unit-acquired weakness (ICUAW) is preferred. The most significant risk factors for the development of ICUAW are sepsis, multiorgan dysfunction and acute respiratory distress syndrome (ARDS). In at least one third of patients, persistent impairment by paralysis, sensory disturbances and balance problems persist when they leave the ICU. At approximately 10%, these leg-accentuated and highly everyday relevant disorders persist over the first year after ICU therapy. Pure myopathy rarely leads to residual disturbances, while the neuropathic component is responsible for long-term impairments.