P. Haidl

Daytime mechanical ventilation in chronic respiratory insufficiency

Chronic respiratory insufficiency (CRI) is associated with nocturnal hypoventilation. Treatment with noninvasive mechanical ventilation (NIMV) performed overnight relieves symptoms of hypoventilation and improves daytime blood gases in CRI. In order to test whether the efficacy of NIMV depends on it being applied during sleep, we conducted a prospective case-controlled study comparing daytime mechanical ventilation (dMV) in awake patients with nocturnal mechanical ventilation (nMV) given in equal quantities. We enrolled 34 clinically stable patients (age 56.1+/-12.1 yrs, 20 females, 14 males) with CRI due to restrictive lung and chest wall disorders and neuromuscular disease. Using a prospective case-control design, matched subjects were allocated alternately to dMV and nMV. After 1 month of NIMV there was considerable symptomatic improvement in both dMV and nMV patients. There were no significant differences between groups in the improvement in daytime arterial carbon dioxide tension (Pa,CO2) (dMV from 7.5+/-0.6 to 5.7+/-0.6 kPa; nMV from 7.2+/-0.5 to 5.8+/-0.5 kPa, p<0.0001) and during the unassisted spontaneous night-time ventilation in terms of transcutaneous Pa,CO2 (dMV from 8.4+/-1.2 to 6.6+/-0.7 kPa; nMV from 8.2+/-1.2 to 6.8+/-0.5 kPa, p<0.0001). We conclude that in many respects, when compared to nocturnal mechanical ventilation, daytime mechanical ventilation in awake patients is equally effective at reversing chronic respiratory insufficiency. Since long-term safety issues were not addressed in this study, we recommend that nocturnal mechanical ventilation should remain the modality of choice for noninvasive mechanical ventilation.

Impact of breathing pattern on work of breathing in healthy subjects and patients with COPD.

The impact of the respiratory pattern on respiratory muscle workload represents an unresolved controversy and is important for the treatment of patients with respiratory disorders and respiratory muscle failure. We designed this study to investigate the relationship of respiratory pattern and inspiratory workload. We measured esophageal pressure and inspiratory flow and calculated work of breathing, tidal volume and respiratory rate. Ten healthy subjects and 10 COPD patients participated and performed five different breathing patterns starting from respiratory rate 12 and tidal volume 1l or quiet breathing, respectively. They were instructed to increase respiratory rate by 50 and 100% as well as tidal volume by 50 and 100% while maintaining constant minute-ventilation. In healthy subjects Delta VT was the single best parameter to predict Delta WOB (R=0.958, R(2)=0.918, p<0.0001). The relationships of changes in tidal volume, respiratory rate and rapid shallow breathing index to changes in WOB were linear. In the COPD Delta VT was also the single best parameter to predict changes in work of breathing (R=0.777, R(2)=0.604, p<0.0001), however the relation of respiratory rate and rapid shallow breathing index to work of breathing was exponential (e-function) with lower indices generating higher workload. We conclude that rapid shallow breathing might be a strategy to compensate for burdensome respiratory mechanics. In COPD patients however we observed a critical threshold where any further increases in rapid shallow breathing index will be of no further benefit.

The Pharmacological Treatment of Chronic Obstructive Pulmonary Disease

BACKGROUND Inhaled corticosteroids (ICS) are markedly less effective against chronic obstructive pulmonary disease (COPD) than against asthma, and also have worse side effects. Whether ICS should be used to treat COPD is currently a matter of debate. METHODS This review is based on pertinent articles retrieved by a selective search in PubMed and the Excerpta Medica Database (EMBASE) carried out in May 2015. We analyzed clinical trials of ICS for the treatment of COPD with a duration of at least one year, along with meta-analyses and COPD guidelines. RESULTS ICS lower the frequency and severity of COPD exacerbations in comparison to monotherapy with a long-acting ß2-agonist, but have no effect on mortality. Compared to placebo, ICS monotherapy lessens the decline of forced expiratory volume in one second (FEV1) over one year by merely 5.80 mL (statistically insignificant; 95% confidence interval: [-0.28; 11.88]) and only marginally improve quality of life. ICS use in patients with COPD increases the risk of pneumonia. A combination of ICS with a long-acting bronchodilator improves FEV1 by 133 mL [105; 161] and lowers the frequency of severe exacerbations by 39% . The frequency of exacerbations is lowered mainly in patients who have many exacerbations; thus, ICS treatment is suitable only for patients with grade III or IV COPD. CONCLUSION ICS monotherapy has no clinically useful effect on pulmonary function in COPD. The main form of drug treatment for COPD is with broncho - dilators, either alone or in combination with ICS. ICS can be given to patients with grade III or IV COPD to make exacerbations less frequent. Patients with an asthma-COPD overlap syndrome (ACOS) can benefit from ICS treatment.

Zerebrale arterielle Gasembolie als Komplikation während einer therapeutischen endobronchialen Anwendung der Argon-Plasma-Koagulation.

In this case report, argon plasma coagulation (APC) was applied in a male individual to treat an occluding tumour of the right middle lobe bronchus with a post-stenotic atelectasis. During attempted recanalisation, the patient suffered a cerebral gas embolism as seen on CT scan, resulting in a distinct neurological deficit. We discuss the available data about cerebral gas embolism as a complication of APC and possibilities to avoid such complications.

TRACHEOSTOMY DECANNULATION: IMPLICATION ON RESPIRATORY MECHANICS

Tracheostomy decreases airway resistance and work of breathing. No comprehensive data are available on respiratory mechanics after tracheostomy decannulation. We evaluated respiratory mechanics after decannulation.

An international randomized study of a home-based self-management program for severe COPD: the COMET.

Introduction Most hospitalizations and costs related to COPD are due to exacerbations and insufficient disease management. The COPD patient Management European Trial (COMET) is investigating a home-based multicomponent COPD self-management program designed to reduce exacerbations and hospital admissions. Design Multicenter parallel randomized controlled, open-label superiority trial. Setting Thirty-three hospitals in four European countries. Participants A total of 345 patients with Global initiative for chronic Obstructive Lung Disease III/IV COPD. Intervention The program includes extensive patient coaching by health care professionals to improve self-management (eg, develop skills to better manage their disease), an e-health platform for reporting frequent health status updates, rapid intervention when necessary, and oxygen therapy monitoring. Comparator is the usual management as per the center’s routine practice. Main outcome measures Yearly number of hospital days for acute care, exacerbation number, quality of life, deaths, and costs.

Humidification of Inspired Oxygen Is Increased With Pre-nasal Cannula, Compared to Intranasal Cannula

BACKGROUND: Oxygen therapy is usually combined with a humidification device, to prevent mucosal dryness. Depending on the cannula design, oxygen can be administered pre- or intra-nasally (administration of oxygen in front of the nasal ostia vs cannula system inside the nasal vestibulum). The impact of cannula design on intra-nasal humidity, however, has not been investigated to date. OBJECTIVE: First, to develop a system, that samples air from the nasal cavity and analyzes the humidity of these samples. Second, to investigate nasal humidity during pre-nasal and intra-nasal oxygen application, with and without humidification. METHODS: We first developed and validated a sampling and analysis system to measure humidity from air samples. By means of this system we measured inspiratory air samples from 12 subjects who received nasal oxygen with an intra-nasal and pre-nasal cannula at different flows, with and without humidification. RESULTS: The sampling and analysis system showed good correlation to a standard hygrometer within the tested humidity range (r = 0.99, P < .001). In our subjects intranasal humidity dropped significantly, from 40.3 ± 8.7% to 35.3 ± 5.8%, 32 ± 5.6%, and 29.0 ± 6.8% at flows of 1, 2, and 3 L, respectively, when oxygen was given intra-nasally without humidification (P = .001, P < .001, and P < .001, respectively). We observed no significant change in airway humidity when oxygen was given pre-nasally without humidification. With the addition of humidification we observed no significant change in humidity at any flow, and independent of pre- or intranasal oxygen administration. CONCLUSIONS: Pre-nasal administration of dry oxygen achieves levels of intranasal humidity similar to those achieved by intranasal administration in combination with a bubble through humidifier. Pre-nasal oxygen simplifies application and may reduce therapy cost.

[Frequency and influence of nosocomial pathogens on weaning outcome and in-hospital mortality in mechanically ventilated patients in a regional weaning centre in comparison of the years 2002 and 2006].

BACKGROUND Patients with nosocomial infections in the intensive care unit (ICU) seem to have a poor prognosis. In this retrospective cohort study we investigated the relationship between weaning outcome, in-hospital mortality and the microbiological proof of nosocomial pathogens from secretions in mechanically ventilated patients in the years 2002 and 2006. PATIENTS AND METHODS 311 patients with long term (> 14 days) invasive (tube or tracheostomy) mechanical ventilation (MV) were enrolled in to the study when they had failed at least two weaning attempts prior to transfer. Microbiological proof of nosocomial pathogens from secretions sampled by the bronchoscope and an X-ray of the chest on admission day (in the transferring ICU and in our ICU) was collected from all patients. RESULTS There was a significant decline of the weaning success rate between 2002 and 2006 (p = 0.001). The In-hospital mortality was higher in 2006 (p = 0.03). The microbiological proof of nosocomial pathogens had no influence on the weanability (exception: MRSA patients in 2002). In both years, patients with infiltrates on X-ray of the chest showed no increased mortality. But in 2006 it took longer to liberate these patients from invasive MV. In 2002 microbiological proof of pathogens was related to higher in-hospital mortality. In 2006, there was no difference concerning mortality in both groups. CONCLUSIONS Proof of nosocomial pathogens and infiltrates had no influence on the weanability of long-term mechanically ventilated patients. For in-hospital mortality, the results are contradictory.

Inhalationsdevices in der modernen Kombinationstherapie chronischer Atemwegserkrankungen

Seit Kurzem sind fixe Kombinationen aus langwirksamen Anticholinergica und langwirksamen β2-Agonisten (LABA) verfugbar, ebenso wie zusatzliche Inhalationssysteme fur die fixe Kombination aus LABA und inhalativen Kortikosteroiden. Die klinische Wirksamkeit der einzelnen Kombinationen unterscheidet sich dabei nicht wesentlich. Daher ist das beste System ist dasjenige Device, das der Patient langfristig korrekt benutzen kann, weil es seiner Praferenz entspricht und sachgerecht und wiederholt geschult wurde.

Therapie der kleinen Atemwege: Grundlagen und Möglichkeiten

This paper describes the possibility of targeting the small airways. In addition to aiding in the therapy for chronic obstructive lung diseases this may prove to be invaluable in the development of treatment strategies for diseases of the bronchioli. Essential factors in peripheral lung deposition include extra-fine particles, a slow and controlled inspiratory flow and an endexspiratory breathhold of 5 - 10 sec (especially for steroids). Due to methodological difficulties, clinical data comparing steroids with larger or extra-fine particles are limited in the field of asthma therapy. However, research suggests a trend for reduced symptoms, positively affected biomarkers and decreased lung hyperinflation when steroids with extra-fine particles are used.