Waveforms Analysis in Patients With Amyotrophic Lateral Sclerosis for Enhanced Efficacy of Mechanically Assisted Coughing.

BACKGROUND: Effectiveness of mechanical assisted coughing with insufflation-exsufflation (MI-E) in amyotrophic lateral sclerosis (ALS) depends largely on severity of bulbar dysfunction, which can generate different upper-airway responses. The aim of the study was to evaluate the use of graphs generated by MI-E in ALS to detect airway obstruction and set parameters to achieve an effective mechanically assisted coughing. METHODS: This was a prospective study enrolling patients with ALS. Several sessions with MI-E were applied, administering different insufflation-exsufflation (± 20, ± 30, ± 40, ± 50 cm H2O) levels in each session. The graphs produced were recorded and analyzed, and the results were used to select the parameters resulting in more effective MI-E. RESULTS: Sixty-nine subjects with ALS were included, yielding a total of 351 analyzed records. A pattern of obstruction during insufflation was detected in 34 subjects (50.7%) and of upper-airway collapse during exsufflation in 18 subjects (26%). The variable associated with obstruction during insufflation was bulbar upper motor neuron dysfunction (odds ratio 7.19 [95% CI 2.32-22.29], P = .001), whereas bulbar lower motor neuron dysfunction was related to upper-airway collapse during exsufflation (odds ratio 0.32 [95% CI 0.11-0.98], P = .046). After parameters were adjusted, in 68 subjects (98.55%) an effective MI-E was achieved. The only variable that predicted absence of alterations in the graphs was Norris bulbar score (odds ratio 0.87 [95% CI 0.78-0.96], P = .007). CONCLUSIONS: Analysis of graphics generated by applying MI-E in ALS was an effective method to detect upper-airway responses and select optimal set parameters. Obstruction during insufflation is related to bulbar upper motor neuron dysfunction and collapse during exsufflation to bulbar lower motor neuron dysfunction.

ROX index as predictor of high flow nasal cannula therapy success in acute respiratory failure due to SARS-CoV-2.

BACKGROUND: High-Flow Nasal Cannula (HFNC) therapy is useful treatment in patients with acute respiratory failure (ARF). The ROX index (ratio of pulse oximetry/fraction of inspired oxygen to respiratory rate) has been evaluated to predict success of HFNC in patients with pneumonia. OBJECTIVE: The aim of this study was to determine whether the ROX Index could predict HFNC therapy success in patients with ARF due to SARS-CoV-2 pneumonia. METHODS: An observational, prospective study was performed including patients admitted with ARF secondary to SARS-CoV-2 pneumonia who met criteria for HFNC therapy initiation. Demographic, radiological, laboratory and clinical course data were collected. The ROX index was calculated at 1 h, 6 h, 12 h and 24 h after starting HFNC. RESULTS: In total 85 patients were included (age, 64.51 + 11.78 years; male, 69.4%). HFNC failed in 47 (55.3%) patients, of whom 45 (97.8%) were initially managed with noninvasive ventilation (NIV). ROX index at 24 h was the best predictor of HFNC success (AUC 0.826, 95%CI 0.593-1.00, p = 0.015) with a cut-off point of 5.35 (S 0.91, Sp 0.79, PPV 0.92, NPP 0.79). In multivariate logistic regression analysis ROX index at 24 h proved the best predictor of HFNC success. CONCLUSIONS: ROX index at 24 h with a cut-off point of 5.35 predicts HFNC success in patients with SARS-Cov-2-induced ARF.

Effect of one-year dextromethorphan/quinidine treatment on management of respiratory impairment in amyotrophic lateral sclerosis.

Treatment with Dextromethorphan/Quinidine (DM/Q) has demonstrated benefit on pseudobulbar affect and bulbar function in amyotrophic lateral sclerosis (ALS). The aim of this study was to assess whether DM/Q could provide long-term improvement in bulbar function and thereby prolong noninvasive respiratory management in ALS. MATERIALS AND METHODS: This prospective, case-cohort study, recruited ALS patients with bulbar dysfunction. Subjects included were compared with cross-matched historical controls. Cases received DM/Q (20/10 mg twice daily) during one-year follow-up; bulbar dysfunction was evaluated with the Norris scale bulbar subscore (NBS) and bulbar subscale of AlSFRS-R (ALSFRSb). RESULTS: In total, 21 cases and 20 controls were enrolled, of whom noninvasive respiratory muscle assistance failed in 6 (28.5%) patients in the DM/Q group, compared with 4 patients (20.0%) in the control group (p = 0.645). Time from study onset to failure of respiratory muscle aids was 5.50 + 1.31 months in the DM/Q group and 5.20 + 1.15 months in the control group (p = 0.663). The adjusted OR for the effect of treatment on failure of noninvasive respiratory muscle aids was 2.12 (95%CI 0.23-33.79, p = 0.592). In the DM/Q group an impairment in scores was found in NBS (F = 19.26, p = 0.000) and ALSFRS-Rb (F = 12.71, p = 0.001) across different months of the study. CONCLUSION: Treatment with DM/Q in ALS is unable to prolong noninvasive respiratory management, and moreover, has no effect on long-term deterioration of bulbar function. Notwithstanding the results on bulbar function, DM/Q was found to improve pseudobulbar affect during one-year follow-up.

Tracheostomy in patients with COVID-19: predictors and clinical features.

BACKGROUND: Around 20% of patients hospitalized for COVID-19 need mechanical ventilation (MV). MV may be prolonged, thus warranting tracheostomy. METHODS: Observational cohort study enrolling patients admitted due to COVID-19. Demographic and clinical data at hospital and ICU admission were collected. The primary endpoint was to identify parameters associated with a need for tracheostomy; secondary endpoints were to analyze the clinical course of patients who needed tracheostomy. RESULTS: 118 patients were enrolled; 37 patients (31.5%) were transferred to ICU, of which 11 (29.72%) needed a tracheostomy due to prolonged MV. Sequential Organ Failure Assessment (SOFA) score at ICU admission (OR 0.65, 95% CI 0.47-0.92, p 0.015) was the only variable found to be associated with increased risk of the need for tracheostomy, with a cut-off point of 4.5 (sensitivity 0.72, specificity 0.73, positive predictive value 0.57 and negative predictive value 0.85). The main complications were nosocomial infection (100%), supraventricular cardiac arrhythmia (45.5%), agitation (54.5%), pulmonary thromboembolism (9.1%) and depression (9.1%). All patients presented with hypoalbuminemia and significant critical illness polyneuropathy. CONCLUSION: SOFA at ICU admission is associated with an increased risk of tracheostomy in patients with COVID-19. Moreover, they present clinical features similar to those with chronic critical illness and suffer SARS-CoV-2-related complications.

Mechanical Insufflation-Exsufflation With Oscillations in Amyotrophic Lateral Sclerosis With Home Ventilation via Tracheostomy.

BACKGROUND: Mechanical insufflation-exsufflation (MI-E) applied via tracheostomy tubes in patients with amyotrophic lateral sclerosis (ALS) who are on home mechanical ventilation via tracheostomy is an effective procedure for respiratory secretion management. Nonetheless, tenacious secretions may remain and increase the risk of respiratory infections. The aim of this study was to determine whether adding oscillations to MI-E could reduce the rate of respiratory infections and the need for bronchoscopy to remove secretions in patients with ALS on home mechanical ventilation via tracheostomy. METHODS: This was a 2-y, prospective, crossover study. Subjects were treated with conventional MI-E and MI-E with oscillations for 2 alternate 6-month periods. Data were collected on episodes of respiratory infections, hospital admission, and number of bronchoscopy procedures. RESULTS: In the 19 ALS subjects enrolled, the median (interquartile range [IQR]) number of acute respiratory infections per subject was 1.0 (0.5-2.0) in the MI-E period and 0.0 (0.0-2.0) in the MI-E plus oscillations period (P = .92). The median (IQR) number of hospital stays was 0.0 (0.0-1.0) in the MI-E period and 0.0 (0.0-1.0) in the MI-E plus oscillations period (P = .80). The median (IQR) number of bronchoscopies per subject was 0.0 (0.0-1.0) in MI-E period and 0.0 (0.0-0.5) in the MI-E plus oscillations period (P = .26). MI-E plus oscillations treatment had no impact on the risk of respiratory infections (odds ratio 3.71, 95% CI 0.81-16.84, P = .09) or the need for bronchoscopy (odds ratio 2.70, 95% CI 0.44-16.68, P = .29). CONCLUSIONS: Adding oscillations to MI-E therapy in subjects with ALS on home mechanical ventilation via tracheostomy did not decrease the risk of respiratory infections, hospital admission, or need for bronchoscopy.

Usefulness of Oscillations Added to Mechanical In-Exsufflation in Amyotrophic Lateral Sclerosis.

BACKGROUND: Assisted coughing via mechanical in-exsufflation (MI-E) is a first-line treatment for secretion management in patients with amyotrophic lateral sclerosis (ALS) with unassisted CPF < 4.25 L/s. Some devices enable oscillations to be added to MI-E (MI-E+O). We sought to determine whether adding oscillations to MI-E enables a reduction in the use of invasive secretion management procedures (ie, bronchoscopy or tracheostomy) in subjects with ALS. METHODS: We conducted a 12-month, prospective, randomized follow-up study of subjects with ALS for whom assisted coughing techniques were indicated. One group was treated with oscillations in addition to MI-E (MI-E+O), and the other group was treated with conventional MI-E. RESULTS: 29 subjects were included in the MI-E group and 27 subjects were included in the MI-E+O group. Five subjects (8.9%) required invasive techniques for secretion management (3 in the MI-E group and 2 in the MI-E+O group, P = .70). Treatment with MI-E+O did not alter the risk of invasive procedures (odds ratio 0.69, 95% CI 0.10-4.50, P = .70). The mean number of respiratory infections was 0.58 ± 0.16 in the MI-E group and 0.025 ± 0.08 in the MI-E+O group (P = .10). Survival was 8.96 ± 0.18 months in the MI-E group and 7.70 ± 0.70 months in the MI-E+O group (P = .10). CONCLUSION: Adding oscillations to MI-E did not enable a reduction in the need to perform invasive procedures for secretion management in subjects with ALS.

Unstable control of breathing can lead to ineffective noninvasive ventilation in amyotrophic lateral sclerosis.

Upper airway obstruction with decreased central drive (ODCD) is one of the causes of ineffective noninvasive ventilation (NIV) in amyotrophic lateral sclerosis (ALS). The aim of this study is to determine the mechanism responsible for ODCD in ALS patients using NIV. This is a prospective study that included ALS patients with home NIV. Severity of bulbar dysfunction was assessed with the Norris scale bulbar subscore; data on upper or lower bulbar motor neuron predominant dysfunction on physical examination were collected. Polysomnography was performed on every patient while using NIV and the ODCD index (ODCDI: number of ODCD events/total sleep time) was calculated. To determine the possible central origin of ODCD, controller gain was measured by inducing a hypocapnic hyperventilation apnoea. Sonography of the upper airway during NIV was performed to determine the location of the ODCD. 30 patients were enrolled; three (10%) had ODCDI >5 h-1. The vast majority of ODCD events were produced during non-rapid eye movement sleep stages and were a consequence of an adduction of the vocal folds. Patients with ODCDI >5 h-1 had upper motor neuron predominant dysfunction at the bulbar level, and had greater controller gain (1.97±0.33 versus 0.91±0.36 L·min-1·mmHg-1; p<0.001) and lower carbon dioxide (CO2) reserve (4.00±0.00 versus 10.37±5.13 mmHg; p=0.043). ODCDI was correlated with the severity of bulbar dysfunction (r= -0.37; p=0.044), controller gain (r=0.59; p=0.001) and CO2 reserve (r= -0.35; p=0.037). ODCD events in ALS patients using NIV have a central origin, and are associated with instability in the control of breathing and an upper motor neuron predominant dysfunction at the bulbar level.

Bulbar impairment score and survival of stable amyotrophic lateral sclerosis patients after noninvasive ventilation initiation.

There is general agreement that noninvasive ventilation (NIV) prolongs survival in amyotrophic lateral sclerosis (ALS) and that the main cause of NIV failure is the severity of bulbar dysfunction. However, there is no evidence that bulbar impairment is a contraindication for NIV. The aim of this study was to determine the effect of bulbar impairment on survival in ALS patients with NIV. ALS patients for whom NIV was indicated were included. Those patients who refused NIV were taken as the control group. 120 patients who underwent NIV and 20 who refused NIV were included. The NIV group presented longer survival (median 18.50 months, 95% CI 12.62-24.38 months) than the no-NIV group (3.00 months, 95% CI 0.82-5.18 months) (p<0.001) and also in those patients with severe bulbar dysfunction (13.00 months (95% CI 9.49-16.50 months) versus 3.00 months (95% CI 0.85-5.15 months), p<0.001). Prognostic factors for ALS using NIV, adjusted for NIV failure, were severity of bulbar dysfunction (hazard ratio (HR) 0.5, 95% CI 0.92-0.97; p=0.001) and time spent with oxygen saturation measured by pulse oximetry <90% (%sleepSpO2 <90) using NIV (HR 1.12, 95% CI 1.01-1.24; p=0.02). Severe bulbar impairment in ALS does not always prevent NIV from being used, but the severity of bulbar dysfunction at NIV initiation and %sleepSpO2 <90 while using NIV appear to be the main prognostic factors of NIV failure in ALS.

Effect of High-Frequency Oscillations on Cough Peak Flows Generated by Mechanical In-Exsufflation in Medically Stable Subjects With Amyotrophic Lateral Sclerosis.

BACKGROUND: Mechanically assisted coughing with mechanical in-exsufflation (MI-E) is recommended for noninvasive management of respiratory secretions in amyotrophic lateral sclerosis (ALS). To improve the effectiveness of the technique, a new device combining MI-E with high-frequency oscillations (HFO) has been developed. This work aimed to assess the effect of HFO on the cough peak flow generated by MI-E in medically stable subjects with ALS. METHODS: This was a prospective study that included subjects with ALS in a medically stable condition. Cough peak flow generated by MI-E was measured in 4 situations: without HFO, with HFO during insufflation, with HFO during exsufflation, and with HFO in both cycles. The parameters used were: insufflation pressure of +40 cm H2O, exsufflation pressure of -40 cm H2O, insufflation time 2 s, exsufflation time 3 s, amplitude of oscillations 10 cm H2O, and frequency of oscillations 15 Hz. RESULTS: Forty-seven subjects with ALS were included: 66% males, 68.2 ± 9.2 y, 40% with bulbar onset, FVC = 1.7 ± 1.1 L, percent-of-predicted FVC = 54.4 ± 26.6%, cough peak flow = 3.8 ± 2.2 L/s, PImax = -39.4 ± 26.4 cm H2O, revised ALS scale = 28.5 ± 9.3, Norris bulbar subscore = 26.1 ± 10.4. No statistical differences were found in cough peak flow generated by MI-E in the 4 situations (without HFO = 4.0 ± 1.2 L/s, with insufflation HFO = 3.9 ± 1.2 L/s, with exsufflation HFO = 4.1 ± 1.2 L/s, with in-exsufflation HFO = 3.9 ± 1.1 L/s). CONCLUSIONS: The addition of HFO to mechanically assisted coughing with MI-E does not have an effect on the cough peak flow of medically stable subjects with ALS.