Is Intermittent Abdominal Pressure Ventilation Still Relevant? A Multicenter Retrospective Pilot Study

Non-invasive ventilatory support (NVS) is a technique used to reduce respiratory work in neuromuscular diseases, preventing the progression of respiratory failure. NVS is usually administered via a nasal or an oronasal mask, causing discomfort, especially in patients ventilated for more than 16 h/day. Intermittent abdominal pressure ventilation (IAPV) differs completely from conventional NVS and consists of a portable ventilator and a corset with Velcro closures as the interface. In our study, the practicability and efficacy of IAPV were studied in three Italian centers monitoring 28 neuromuscular patients using IAPV who were then retrospectively analyzed. The primary outcomes were an improvement in hypoxemia and the normalization of hypercapnia, and the secondary outcome was an improvement in quality of life. Data were collected at baseline (T0) and after two hours of ventilation (T1), with follow-ups at three months (T2) and six months (T3). Statistical significance was found for PaCO₂ over time (F (2.42) = 7.63, p = 0.001) and PaO₂ (W = 0.539, p = 0.033). The time of NVS usage also significantly affected the quality of life (F (2.14) = 6.90, p = 0.010), as seen when comparing T0 and T3. As an alternative ventilation method, IAPV is still relevant today and could become a key part of daytime support, especially for patients who do not tolerate standard daytime NVS with an oral interface.

NK Cell Subpopulations and Receptor Expression in Recovering SARS-CoV-2 Infection

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the pandemic of coronavirus disease (COVID-19). Whereas in most cases COVID-19 is asymptomatic or pauci-symptomatic, extremely severe clinical forms are observed. In this case, complex immune dysregulations and an excessive inflammatory response are reported and are the main cause of morbidity and mortality. Natural killer cells are key players in the control of viral infection, and their activity is regulated by a tight balance between activating and inhibitory receptors; an alteration of NK activity was suggested to be associated with the development of severe forms of COVID-19. In this study, we analyzed peripheral NK cell subpopulations and the expression of activating and inhibitory receptors in 30 patients suffering from neurological conditions who recovered from mild, moderate, or severe SARS-CoV-2 infection, comparing the results to those of 10 SARS-CoV-2-uninfected patients. Results showed that an expansion of NK subset with lower cytolytic activity and an augmented expression of the 2DL1 inhibitory receptor, particularly when in association with the C2 ligand (KIR2DL1-C2), characterized the immunological scenario of severe COVID-19 infection. An increase of NK expressing the ILT2 inhibitory receptor was instead seen in patients recovering from mild or moderate infection compared to controls. Results herein suggest that the KIR2DL1-C2 NK inhibitory complex is a risk factor toward the development of severe form of COVID-19. Our results confirm that a complex alteration of NK activity is present in COVID-19 infection and offer a molecular explanation for this observation.

COVID-19 salivary Raman fingerprint: innovative approach for the detection of current and past SARS-CoV-2 infections

The pandemic of COVID-19 is continuously spreading, becoming a worldwide emergency. Early and fast identification of subjects with a current or past infection must be achieved to slow down the epidemiological widening. Here we report a Raman-based approach for the analysis of saliva, able to significantly discriminate the signal of patients with a current infection by COVID-19 from healthy subjects and/or subjects with a past infection. Our results demonstrated the differences in saliva biochemical composition of the three experimental groups, with modifications grouped in specific attributable spectral regions. The Raman-based classification model was able to discriminate the signal collected from COVID-19 patients with accuracy, precision, sensitivity and specificity of more than 95%. In order to translate this discrimination from the signal-level to the patient-level, we developed a Deep Learning model obtaining accuracy in the range 89-92%. These findings have implications for the creation of a potential Raman-based diagnostic tool, using saliva as minimal invasive and highly informative biofluid, demonstrating the efficacy of the classification model.

Prevalence and prognostic impact of somatic mutations in patients with heart failure and reduced ejection fraction

Introduction

Somatic mutations in hematopoietic cells are associated with age and have been associated with higher mortality in apparently healthy adults, especially due to atherosclerotic disease. In animal models, somatic mutations are associated with atherosclerosis progression and myocardial dysfunction, especially when gene TET2 is affected. Preliminary clinical data, referred to ischemic heart failure (HF), have associate the presence of these acquired mutations with impaired prognosis.

Purpose

To study the prevalence of somatic mutations in patients with heart failure with reduced ejection fraction (HFrEF) and their impact on long-term prognosis.

Methods

We studied a cohort of elderly patients (more than 60 years old) hospitalized with HFrEF (LVEF<45%). The presence of somatic mutations was assessed using next generation sequencing (Illumina HiSeq 2500), with a mutated allelic fraction of at least 2% and a panel of 55 genes related with clonal hematopoiesis. Patients were followed-up for a median of three years. The study endpoint was a composite of death or readmission for worsening HF. Kaplan-Meier analysis (log-rank test) and Cox proportional hazards regression models were performed adjusting for age, sex and LVEF.

Results

A total of 62 patients (46 males (74.2%), age 74±7.5 years) with HFrEF (LVEF 29.7±7.8%) were enrolled in the study. The ischemic etiology was present in 54% of patients. Somatic mutations in Dnmt3a or Tet2 were present in 11 patients (17.7%). No differences existed in baseline characteristics except for a higher prevalence of atrial fibrillation in patients with somatic mutations (70% vs. 40%, p=0.007). During the follow-up period, 40 patients (64.5%) died and 38 (61.3%) had HF re-admission. The KM survival analysis for the combined event is shown in Figure 1. Compared with patients without somatic mutations and after adjusting for covariates, there was an increased risk of adverse outcomes when the somatic mutations were present (HR 3.6, 95% CI [1.6, 7.8], p=0.0014). This results remains considering death as a competing risk (Gray's test p=0.0097) and adjusting for covariates (HR = 2.21 95% CI [0.98, 5], p=0.0556).

Conclusions

Somatic mutation are present in patients with HFrEF and determine a higher risk of adverse events in the follow-up. Further studies are needed to assess the clinical implications of these findings.

Figure 1

Funding Acknowledgement

Type of funding source: None

Daytime noninvasive ventilatory support for patients with ventilatory pump failure: a narrative review

Over the past three decades, the use of noninvasive ventilation or "NIV" to assuage symptoms of hypoventilation for patients with early onset or mild ventilatory pump failure has been extended to up to the use of continuous noninvasive ventilatory support (CNVS) at full ventilatory support settings as a definitive alternative to tracheostomy mechanical ventilation. NVS, along with mechanical insufflation-exsufflation, now provides a noninvasive option for the management of both chronic and acute respiratory failure for these patients. The most common diagnoses for which these methods are useful include chest wall deformities, neuromuscular diseases, morbid obesity, high level spinal cord injury and idiopathic, primary or secondary disorders of the ventilatory control. Thus, NVS is being used in diverse settings: critical care units, medical wards, at home, and in extended care. The aim of this review is to examine the techniques used for daytime support.

Daytime noninvasive ventilatory support for patients with ventilatory pump failure: a narrative review

Over the past three decades, the use of noninvasive ventilation or “NIV” to assuage symptoms of hypoventilation for patients with early onset or mild ventilatory pump failure has been extended to up to the use of continuous noninvasive ventilatory support (CNVS) at full ventilatory support settings as a definitive alternative to tracheostomy mechanical ventilation. NVS, along with mechanical insufflation-exsufflation, now provides a noninvasive option for the management of both chronic and acute respiratory failure for these patients. The most common diagnoses for which these methods are useful include chest wall deformities, neuromuscular diseases, morbid obesity, high level spinal cord injury and idiopathic, primary or secondary disorders of the ventilatory control. Thus, NVS is being used in diverse settings: critical care units, medical wards, at home, and in extended care. The aim of this review is to examine the techniques used for daytime support.

Respiratory muscle testing in amyotrophic lateral sclerosis: a practical approach

In amyotrophic lateral sclerosis (ALS), respiratory muscle weakness leads to respiratory failure and death. Non-invasive positive pressure ventilation (NIPPV) appears to reduce lung function decline, thus improving survival and quality-of-life of patients affected by the disease. Unfortunately, clinical features and timing to start NIPPV are not well defined. Starting from recent findings, we examine established and novel tests of respiratory muscle function that could help clinicians decide whether and when to start NIPPV in ALS. Non-invasive tests estimate the function of inspiratory, expiratory, and bulbar muscles, whereas clinical examination allows to assess the overall neurologic and respiratory symptoms and general conditions. Most of the studies recommend that together with a thorough clinical evaluation of the patient according to current guidelines, vital capacity, maximal static and sniff nasal inspiratory pressures, maximal static expiratory pressures and peak cough expiratory flow, and nocturnal pulse oximetry be measured. A sound understanding of physiology can guide the physician also through the current armamentarium for additional supportive treatments for ALS, such as symptomatic drugs and new treatments to manage sialorrhea and thickened saliva, cough assistance, air stacking, and physiotherapy. In conclusion, careful clinical and functional evaluation of respiratory function and patient's preference are key determinants to decide "when" and "to whom" respiratory treatments can be provided.

Impact of an early respiratory care programme with non-invasive ventilation adaptation in patients with amyotrophic lateral sclerosis

BACKGROUND AND PURPOSE

Forced vital capacity (FVC) <80% is one of the key indications for starting non-invasive ventilation (NIV) in amyotrophic lateral sclerosis (ALS). It was hypothesized that a very early start of NIV could lengthen the free interval before death compared to later-start NIV; as a secondary outcome, the survival rate of patients on NIV without tracheotomy was also evaluated.

METHODS

This retrospective study was conducted on 194 ALS patients, divided into a later group (LG) with FVC <80% at NIV prescription (n = 129) and a very early group (VEG) with FVC ≥80% at NIV prescription (n = 65). Clinical and respiratory functional data and time free to death between groups over a 3-year follow-up were compared.

RESULT

At 36 months from diagnosis, mortality was 35% for the VEG versus 52.7% for the LG (P = 0.022). Kaplan-Meier survival curves adjusted for tracheotomy showed a lower probability of death (P = 0.001) for the VEG as a whole (P = 0.001) and for the non-bulbar (NB) subgroup (P = 0.007). Very early NIV was protective of survival for all patients [hazard ratio (HR) 0.45; 95% confidence interval (CI) 0.28-0.74; P = 0.001] and for the NB subgroup (HR 0.43; 95% CI 0.23-0.79; P = 0.007), whilst a tracheotomy was protective for all patients (HR 0.27; 95% CI 0.15-0.50; P = 0.000) and both NB (HR 0.26; 95% CI 0.12-0.56; P = 0.001) and bulbar subgroups (HR 0.29; 95% CI 0.11-0.77; P = 0.013). Survival in VEG patients on NIV without tracheotomy was three times that for the LG (43.1% vs. 14.7%).

CONCLUSION

Very early NIV prescription prolongs the free time from diagnosis to death in NB ALS patients whilst tracheotomy reduces the mortality risk in all patients.

Use of Noninvasive Ventilation During Feeding Tube Placement

Parenteral nutrition is indicated in amyotrophic lateral sclerosis (ALS) when dysphagia, loss of appetite, and difficulty protecting the airways cause malnutrition, severe weight loss, dehydration, and increased risk of aspiration pneumonia. The aim of this review is to compare percutaneous endoscopic gastrostomy (PEG), radiologically inserted G-tube (RIG), and percutaneous radiologic gastrostomy (PRG) in patients with ALS, performed with or without noninvasive ventilation (NIV). We searched PubMed, MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), the EBSCO Online Research Database, and Scopus up to December 2015. A priori selection included all randomized controlled trials (RCTs), quasi-randomized trials, and prospective and retrospective studies. The primary outcome was 30-d survival. We found no RCTs or quasi-RCTs. Seven studies about the implementation of the PEG/RIG procedure during the use of NIV and 5 studies without NIV were included. In another study of 59 subjects undergoing open gastrostomy, all with vital capacity < 30% of normal, 18 of whom were dependent on continuous NIV at full ventilatory support settings, there were no respiratory complications. Thus, the use of NIV during the implementation of these procedures, especially when used at full ventilatory support settings of pressure preset 18-25 cm H₂O, can support alveolar ventilation before, during, and after the procedures and prevent respiratory complications. The procedures investigated appear equivalent, but the methodological quality of the studies could be improved. Possible benefits with regard to nutrition parameters, quality of life, and psychological features need to be further investigated.

Reformulated meat products protect against ischemia-induced cardiac damage

The protective effects of the antioxidants present in food are of great relevance for cardiovascular health. This study evaluates whether the extracts from reformulated meat products with a reduction in fat and/or sodium content exert a cardioprotective effect against ischemia-induced oxidative stress in cardiomyocytes, compared with non-meat foods. Ischemic damage caused loss of cell viability, increased reactive oxygen species and lipid peroxidation and decreased the antioxidant activity. Pretreatment for 24 h with digested or non-digested extracts from reformulated meat products led to protection against ischemia-induced oxidative damage: increased cell viability, reduced oxidative stress and restored the antioxidant activity. Similar results were obtained using extracts from tuna fish, but not with the extracts of green peas, salad or white beans. These results suggest that reformulated meat products have a beneficial impact in protecting cardiac cells against ischemia, and they may represent a source of natural antioxidants with benefits for cardiovascular health.

Sleep-related breathing disorders and non-invasive ventilation

Non-invasive mechanical ventilation (NPPV) was originally used in patients with acute respiratory impairment or exacerbations of chronic respiratory diseases, as an alternative to the endotracheal tube. Over the last thirty years NPPV has been also used at night in patients with stable chronic lung disease such as obstructive sleep apnea, the overlap syndrome (chronic obstructive pulmonary disease and obstructive sleep apnea), neuromuscular disorders, obesity-hypoventilation syndrome, and in other conditions such as sleep disorders associated with congestive heart failure (Cheyne-Stokes respiration). In this no-systematic review we discuss the different types of NPPV, the specific conditions in which they can be used and the indications, recommendations and evidence supporting the efficacy of NPPV. Optimizing patient acceptance and adherence to non-invasive ventilation treatment is challenging. The treatment of sleep-related disorders is a life-threatening condition. The optimal level of treatment should be determined in a sleep laboratory. Side effects directly affecting the patient’s adherence to treatment are known. The most common are nasopharyngeal symptoms including increased congestion and rhinorrhea; these effects are related to reduced humidity of inspired gas. Humidification of delivered gas may improve these symptoms.

A review of options for treating sialorrhea in amyotrophic lateral sclerosis

Sialorrhea or drooling represents quite a common problem in patients with amyotrophic lateral sclerosis (ALS). In this review, we describe the possible treatments for this issue. Current medical management is not always effective: anticholinergic drugs (atropine, glycopyrrolate, amitriptyline, hyoscyamine, and transdermal scopolamine) are often used, but there is very little evidence of their effectiveness in patients with ALS. More invasive treatments, such as botulinum toxin injections and/or radiation therapy in the salivary glands, can be considered when anticholinergic drugs are not effective. In this review, we also explore the possible surgical options for treatment of sialorrhea. Although no specific studies have been conducted on patients with ALS, surgical therapies might represent a valid option for treatment of sialorrhea since there is no tachyphylaxis or need for repeated therapeutic sessions.

Non-invasive ventilation in the treatment of sleep-related breathing disorders: A review and update

Non-invasive mechanical ventilation (NIV) was originally used in patients with acute respiratory compromises or exacerbations of chronic respiratory diseases as an alternative to intubation. Over the last thirty years NIV has been used during the night in patients with stable chronic lung diseases such as obstructive sleep apnea, the overlap syndrome (COPD and obstructive sleep apnea), neuromuscular disorders, obesity-hypoventilation syndrome and in other conditions such as sleep disorders associated with congestive heart failure. In this review we discuss the different types of NIV, the specific conditions in which they can be used as well as the indications, recommendations, and evidence supporting the efficacy of NIV.

Pathological and virological studies of experimental parvoviral enteritis in calves

Calves held in isolation showed a progressive decline in maternally derived antibody titres to bovine parvovirus but low concentrations of inhibitors resistant to heat and kaolin treatment persisted as the animals matured. These inhibitors had both haemagglutination inhibition and plaque neutralising activity and were considered to be of non-specific origin. Following oral challenge with bovine parvovirus, calves developed mild to moderate diarrhoea, with lymphopenia and viraemia. Sequential virological and immunofluorescent studies showed that the virus initially infected tonsils and intestinal tract, subsequently spreading to systemic lymphoid tissues. Histological and scanning electron microscopic examinations revealed moderate small intestinal villus atrophy and fusion due to crypt damage, together with lymphoid necrosis predominantly associated with the intestinal tract and thymus. Although the disease was not very severe, this may have been because the low parasite burden in the animals reduced mitotic activity in susceptible tissues.

[Unfavourable effects of the sublingual isosorbide dinitrate. Osbervations on nine personal cases (author's transl)]

Nine among our patients have shown some phenomena of intolerance owing to the engagement of the sublingual isosorbide dinitrate. Even if these troubles are comparatively rare (no more than 10% of the cases we have examined), nevertheless we deem it necessary to exhort to some prudence in the administration of this drug, at least for the first time.