Continuous and bilevel positive airway pressure may improve radiotherapy delivery in patients with intra-thoracic tumors.

Background: Minimizing tumor motion in radiotherapy for intra-thoracic tumors reduces side-effects by limiting radiation exposure to healthy tissue. Continuous or Bilevel Positive Airway Pressure (CPAP/BiPAP) could achieve this, since it could increase lung inflation and decrease tidal volume variability. We aim to identify the better CPAP/BiPAP setting for minimizing tumor motion. Methods: In 10 patients (5 with lung cancer, 5 with other intra-thoracic tumors), CPAP/BiPAP was tested with the following settings for 10 min each: CPAP 5, 10 and 15 cmH2O and BiPAP 14/10 cmH2O with a lower (7 breaths/min) and higher back-up respiratory rate (BURR initially 1 breath/min above the spontaneous breathing frequency, with the option to adjust if the patient continued to initiate breaths). Electrical impedance tomography was used to analyse end-expiratory lung impedance (EELI) as an estimate of end-expiratory lung volume and tidal impedance variation (TIV) as an estimate of tidal volume. Results: Nine out of ten patients tolerated all settings; one patient could not sustain CPAP-15. A significant difference in EELI was observed between settings (χ2 22.960, p < 0.001), with most increase during CPAP-15 (median (IQR) 1.03 (1.00 - 1.06), normalized to the EELI during spontaneous breathing). No significant differences in TIV and breathing variability were found between settings. Conclusions: This study shows that the application of different settings of CPAP/BiPAP in patients with intra-thoracic tumors is feasible and tolerable. BiPAP with a higher BURR may offer the greatest potential for mitigating tumor motion among the applied settings, although further research investigating tumor motion should be conducted.

Analysis and applications of respiratory surface EMG: report of a round table meeting.

Surface electromyography (sEMG) can be used to measure the electrical activity of the respiratory muscles. The possible applications of sEMG span from patients suffering from acute respiratory failure to patients receiving chronic home mechanical ventilation, to evaluate muscle function, titrate ventilatory support and guide treatment. However, sEMG is mainly used as a monitoring tool for research and its use in clinical practice is still limited-in part due to a lack of standardization and transparent reporting. During this round table meeting, recommendations on data acquisition, processing, interpretation, and potential clinical applications of respiratory sEMG were discussed. This paper informs the clinical researcher interested in respiratory muscle monitoring about the current state of the art on sEMG, knowledge gaps and potential future applications for patients with respiratory failure.

Passive Tracer Visualization to Simulate Aerodynamic Virus Transport in Noninvasive Respiratory Support Methods.

BACKGROUND: Various forms of noninvasive respiratory support methods are used in the treatment of hypoxemic CO-VID-19 patients, but limited data are available about the corresponding respiratory droplet dispersion. OBJECTIVES: The aim of this study was to estimate the potential spread of infectious diseases for a broad selection of oxygen and respiratory support methods by revealing the therapy-induced aerodynamics and respiratory droplet dispersion. METHODS: The exhaled air-smoke plume from a 3D-printed upper airway geometry was visualized by recording light reflection during simulated spontaneous breathing, standard oxygen mask application, nasal high-flow therapy (NHFT), continuous positive airway pressure (CPAP), and bilevel positive airway pressure (BiPAP). The dispersion of 100 µm particles was estimated from the initial velocity of exhaled air and the theoretical terminal velocity. RESULTS: Estimated droplet dispersion was 16 cm for unassisted breathing, 10 cm for Venturi masks, 13 cm for the nebulizer, and 14 cm for the nonrebreathing mask. Estimated droplet spread increased up to 34 cm in NHFT, 57 cm in BiPAP, and 69 cm in CPAP. A nonsurgical face mask over the NHFT interface reduced estimated droplet dispersion. CONCLUSIONS: During NHFT and CPAP/BiPAP with vented masks, extensive jets with relatively high jet velocities were observed, indicating increased droplet spread and an increased risk of droplet-driven virus transmission. For the Venturi masks, a nonrebreathing mask, and a nebulizer, estimated jet velocities are comparable to unassisted breathing. Aerosols are transported unboundedly in all these unfiltered therapies. The adequate use of protective measures is of vital importance when using noninvasive unfiltered therapies in infectious respiratory diseases.

[Home oxygen therapy; indications are still limited]. / Zuurstoftherapie thuis.

Prescription of long term oxygen treatment ( LTOT),based on old studies, is only indicated if there is severe hypoxaemia at rest (PaO2 < 8,0 kPa) and should be used atleast 15 hours per day.However as newer treatments like nocturnal non-invasive ventilatory support showed to be beneficial, LTOT stands not on its own but should be part of a multidimensional approach in individual patients with COPD.

"Tricks and tips for home mechanical ventilation" Home mechanical ventilation: set-up and monitoring protocols.

In this part of the review series "Tricks and tips for home mechanical ventilation", we will discuss the evidence with regard to the place and manner of home mechanical ventilation initiation and follow-up. Outsourcing more and more of this chronic care to the home situation is a big challenge for the future: especially for the home situation, monitoring has to be non-invasive, reliable and easy to use, data security needs to be ensured, signals need to be integrated and preferably automatically processed and algorithms need to be developed based on clinically relevant outcomes.

Respiratory muscle activity and dyspnea during exercise in chronic obstructive pulmonary disease.

We aimed to determine by non-invasive EMG, whether during exercise: (1) COPD patients increase scalene and intercostal EMG activity, (2) increased EMG activity is associated with increased dyspnea, and (3) the ratio between EMG activity and volume displacement is increased in COPD compared to healthy subjects (HS). During a maximal incremental cycle test, scalene and intercostal EMG was derived transcutaneously in 17 COPD patients and 10 HS. Dyspnea was quantified using a Borg scale, ranging from zero to 10 (maximal dyspnea). For analyses the ratio between inspiratory muscle activity during exercise and activity during quiet breathing was used (logEMGAR). In COPD patients, scalene and intercostal activity increased at greater rate early in exercise compared to that of the HS. With a doubling of the logEMGAR, in COPD, dyspnea increased with 2.8/3.8 points, while in the HS, dyspnea increased less with 1.1/1.4 points. In COPD, there was a larger increase in EMG activity relatively to tidal volume increases.

Nocturnal non-invasive ventilation in addition to rehabilitation in hypercapnic patients with COPD.

BACKGROUND: Long-term non-invasive positive pressure ventilation (NIPPV) might improve the outcomes of pulmonary rehabilitation in patients with chronic obstructive pulmonary disease (COPD) with chronic respiratory failure. A study was undertaken to investigate whether nocturnal NIPPV in addition to pulmonary rehabilitation improves health-related quality of life, functional status and gas exchange compared with pulmonary rehabilitation alone in patients with COPD with chronic hypercapnic respiratory failure. METHODS: 72 patients with COPD were randomly assigned to nocturnal NIPPV in addition to rehabilitation (n = 37) or rehabilitation alone (n = 35). Outcome measures were assessed before and after the 3-month intervention period. RESULTS: The Chronic Respiratory Questionnaire total score improved 15.1 points with NIPPV + rehabilitation compared with 8.7 points with rehabilitation alone. The difference of 7.5 points was not significant (p = 0.08). However, compared with rehabilitation alone, the difference in the fatigue domain was greater with NIPPV + rehabilitation (mean difference 3.3 points, p<0.01), as was the improvement in the Maugeri Respiratory Failure questionnaire total score (mean difference -10%, p<0.03) and its cognition domain (mean difference -22%, p<0.01). Furthermore, the addition of NIPPV improved daytime arterial carbon dioxide pressure (mean difference -0.3 kPa; p<0.01) and daily step count (mean difference 1269 steps/day, p<0.01). This was accompanied by an increased daytime minute ventilation (mean difference 1.4 l; p<0.001). CONCLUSION: Non-invasive ventilation augments the benefits of pulmonary rehabilitation in patients with COPD with chronic hypercapnic respiratory failure as it improves several measures of health-related quality of life, functional status and gas exchange.

Health-related quality of life in COPD patients with chronic respiratory failure.

The Maugeri Respiratory Failure (MRF-28) and Severe Respiratory Insufficiency (SRI) questionnaires were recently developed to assess health-related quality of life (HRQoL) in patients with chronic respiratory failure, although not exclusively in chronic obstructive pulmonary disease (COPD) patients. The aim of the present study was to investigate whether the MRF-28 and SRI are reliable and valid HRQoL questionnaires in COPD patients with chronic hypercapnic respiratory failure (CHRF). In total, 72 COPD patients with CHRF underwent pulmonary function and exercise testing, and completed the MRF-28, the SRI, the Chronic Respiratory Questionnaire (CRQ), the Hospital Anxiety and Depression Scale, the Groningen Activity and Restriction Scale and two dyspnoea indexes. Physical domain scores of the questionnaires correlated with exercise tolerance, dyspnoea and daily activities, while psychological domains correlated strongly with anxiety and depression. Anxiety scores accounted for 51 and 56% of the total explained variance in total CRQ and SRI scores, respectively. The emphasis of the MRF-28 was restrictions in activities of daily living (52% of total variance). In conclusion, the present study showed that the Maugeri Respiratory Failure and Severe Respiratory Insufficiency questionnaires were reliable and valid questionnaires in chronic obstructive pulmonary disease patients with chronic hypercapnic respiratory failure. While the emphasis in the Maugeri Respiratory Failure questionnaire is on activities of daily living, the Severe Respiratory Insufficiency questionnaire, like the Chronic Respiratory Questionnaire, is more related to anxiety and depression.

A patient treated with olanzapine developing diabetes de novo: proposal for hyperglycaemia screening.

We report a patient with schizophrenia who developed diabetes mellitus during treatment with olanzapine. The case confirms the pattern of atypical antipsychotic-related diabetic emergencies: rapid onset in relatively young patients, often with severe glucose derangements and serious complications. As diabetic emergencies have a high morbidity and mortality, regular glucose screening should be performed in patients with schizophrenia treated with atypical antipsychotics.