"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

Effects of non-invasive positive pressure ventilation (NIPPV) in stable chronic obstructive pulmonary disease (COPD)

This review provides an overview of the randomised controlled trials covering the topic of chronic non-invasive positive pressure ventilation (NIPPV) in severe stable COPD patients. Studies investigating patients receiving bilevel NIPPV via nasal, oronasal or total face mask interfaces for at least 1 week or more, were described. Eight RCTs were included, from which six trials used NIPPV for up to 3 months (short-term) and two trials also obtained long-term effects (3 months to ≥2 years). Outcome parameters were: arterial blood gases, pulmonary function, respiratory mechanics, respiratory muscle strength, dyspnoea, exercise tolerance, health-related quality of life, neuropsychologic function, sleep quality, hospital admissions and survival. We found that NIPPV in addition to standard care can have beneficial effects on certain outcome measures, however results are conflicting. Therefore, evidence is insufficient to recommend NIPPV routinely in stable but severe COPD patients. Nevertheless, it seems that hypercapnic patients, who receive enough time to adjust to the ventilator and so obtain improved ventilation, could benefit from NIPPV

Home oxygen therapy; indications are still limited

Prescription of long term oxygen treatment ( LTOT),based on old studies, is only indicated if there is severe hypoxaemia at rest (PaO2 &lt; 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.</p

Improvement in hypercapnia does not predict survival in COPD patients on chronic noninvasive ventilation

Purpose: It has recently been shown that chronic noninvasive ventilation (NIV) improves a number of outcomes including survival, in patients with stable hypercapnic COPD. However, the mechanisms responsible for these improved outcomes are still unknown. The aim of the present study was to identify parameters associated with: 1) an improved arterial partial pressure of carbon dioxide (PaCO2) and 2) survival, in a cohort of hypercapnic COPD patients treated with chronic NIV. Patients and methods: Data from 240 COPD patients treated with chronic NIV were analyzed. Predictors for the change in PaCO2 and survival were investigated using multivariate linear and Cox regression models, respectively. Results: A higher level of bicarbonate before NIV initiation, the use of higher inspiratory ventilator pressures, the presence of anxiety symptoms, and NIV initiated following an exacerbation compared to NIV initiated in stable disease were associated with a larger reduction in PaCO2. A higher body mass index, a higher FEV1, a lower bicarbonate before NIV initiation, and younger age and NIV initiation in stable condition were independently associated with better survival. The change in PaCO2 was not associated with survival, neither in a subgroup of patients with a PaCO2 >7.0 kPa before the initiation of NIV. Conclusion: Patients with anxiety symptoms and a high bicarbonate level at NIV initiation are potentially good responders in terms of an improvement in hypercapnia. Also, higher inspiratory ventilator pressures are associated with a larger reduction in PaCO2. However, the improvement in hypercapnia does not seem to be associated with an improved survival and emphasizes the need to look beyond PaCO2 when considering NIV initiation

High-flow nasal cannula oxygen therapy for admitted COPD-patients:A retrospective cohort study

BACKGROUND: The use of High-flow nasal cannula (HFNC) is increasing in admitted COPD-patients and could provide a step in between non-invasive ventilation (NIV) and standard oxygen supply. Recent studies demonstrated that HFNC is capable of facilitating secretion removal and reduce the work of breathing. Therefore, it might be of advantage in the treatment of acute exacerbations of COPD (AECOPD). No randomized trials have assessed this for admitted COPD-patients on a regular ward and only limited data from non-randomized studies is available. OBJECTIVES: The aim of our study was to identify the reasons to initiate treatment with HFNC in a group of COPD-patients during an exacerbation, further identify those most likely to benefit from HFNC treatment and to find factors associated with treatment success on the pulmonary ward. MATERIAL AND METHODS: This retrospective study included COPD-patients admitted to the pulmonary ward and treated with HFNC from April 2016 until April 2019. Only patients admitted with severe acute exacerbations were included. Patients who had an indication for NIV-treatment where treated with NIV and were included only if they subsequently needed HFNC, e.g. when they did not tolerate NIV. Known asthma patients were excluded. RESULTS: A total of 173 patients were included. Stasis of sputum was the indication most reported to initiate HFNC-treatment. Treatment was well tolerated in 83% of the patients. Cardiac and vascular co-morbidities were significantly associated with a smaller chance of successful treatment (Respectively OR = 0.435; p = 0.013 and OR = 0.493;p = 0.035). Clinical assessment judged HFNC-treatment to be successful in 61% of the patients. Furthermore, in-hospital treatment with NIV was associated with a higher chance of HFNC failure afterwards (OR = 0.439; p = 0.045). CONCLUSION: This large retrospective study showed that HFNC-treatment in patients with an AECOPD was initiated most often for sputum stasis as primary reason. Factors associated with improved outcomes of HFNC-treatment was the absence of vascular and/or cardiac co-morbidities and no need for in-hospital NIV-treatment

Chronic non-invasive ventilation for chronic obstructive pulmonary disease

BACKGROUND: Chronic non-invasive ventilation (NIV) is increasingly being used to treat people with COPD who have respiratory failure, but the evidence supporting this treatment has been conflicting.OBJECTIVES: To assess the effects of chronic non-invasive ventilation at home via a facial mask in people with COPD, using a pooled analysis of IPD and meta-analysis.SEARCH METHODS: We searched the Cochrane Airways Register of Trials, MEDLINE, Embase, PsycINFO, CINAHL, AMED, proceedings of respiratory conferences, clinical trial registries and bibliographies of relevant studies. We conducted the latest search on 21 December 2020.SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing chronic NIV for at least five hours per night for three consecutive weeks or more (in addition to standard care) versus standard care alone, in people with COPD. Studies investigating people initiated on NIV in a stable phase and studies investigating NIV commenced after a severe COPD exacerbation were eligible, but we reported and analysed them separately. The primary outcomes were arterial blood gases, health-related quality of life (HRQL), exercise capacity (stable COPD) and admission-free survival (post-exacerbation COPD). Secondary outcomes for both populations were: lung function, COPD exacerbations and admissions, and all-cause mortality. For stable COPD, we also reported respiratory muscle strength, dyspnoea and sleep efficiency.DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. After inclusion of a study, we requested the IPD. We analysed continuous and time-to-event data using linear- and cox-regression mixed-effect models with a random effect on study level. We analysed dichotomous IPD using generalised estimating equations. We adjusted all models for age and sex. We assessed changes in outcomes after three and 12 months. We also conducted a meta-analysis on aggregated trial data.MAIN RESULTS: We included 14 new RCTs in this review update, in addition to the seven previously included. Seventeen studies investigated chronic NIV in stable COPD and four studies investigated chronic NIV commenced after a severe COPD exacerbation. Three studies compared NIV to sham continuous positive airway pressure (2 to 4 cmH2O). Seven studies used a nasal mask, one study used an oronasal mask and eight studies used both interfaces. Five studies did not report the interface. The majority of trials (20/21) were at high risk of performance bias due to an unblinded design. We considered 11 studies to have a low risk of selection bias and 13 to have a low risk of attrition bias. We collected and analysed the IPD from 13 stable COPD studies (n = 778, 68% of the participants included) and from three post-exacerbation studies (n = 364, 96% of the participants included). In the stable COPD group, NIV probably results in a minor benefit on the arterial partial pressure of oxygen (PaO2) after three months (adjusted mean difference (AMD) 0.27 kPa, 95% CI 0.04 to 0.49; 9 studies, 271 participants; moderate-certainty evidence), but there was little to no benefit at 12 months (AMD 0.09 kPa, 95% CI -0.23 to 0.42; 3 studies, 171 participants; low-certainty evidence). The arterial partial pressure of carbon dioxide (PaCO2) was reduced in participants allocated to NIV after three months (AMD -0.61 kPa, 95% CI -0.77 to -0.45; 11 studies, 475 participants; high-certainty evidence) and persisted up to 12 months (AMD -0.42 kPa, 95% CI -0.68 to -0.16; 4 studies, 232 participants; high-certainty evidence). Exercise capacity was measured with the 6-minute walking distance (minimal clinical important difference: 26 m). There was no clinically relevant effect of NIV on exercise capacity (3 months: AMD 15.5 m, 95% CI -0.8 to 31.7; 8 studies, 330 participants; low-certainty evidence; 12 months: AMD 26.4 m, 95% CI -7.6 to 60.5; 3 studies, 134 participants; very low-certainty evidence). HRQL was measured with the Severe Respiratory Insufficiency and the St. Georges's Respiratory Questionnaire and may be improved by NIV, but only after three months (3 months: standardised mean difference (SMD) 0.39, 95% CI 0.15 to 0.62; 5 studies, 259 participants; very low-certainty evidence; 12 months: SMD 0.15, 95% CI -0.13 to 0.43; 4 studies, 200 participants; very low-certainty evidence). Lastly, the risk for all-cause mortality is likely reduced by NIV (adjusted hazard ratio (AHR) 0.75, 95% CI 0.58 to 0.97; 3 studies, 405 participants; moderate-certainty evidence). In the post-exacerbation COPD group, there was little to no benefit on the PaO2 after three months, but there may be a slight decrease after 12 months (3 months: AMD -0.10 kPa, 95% CI -0.65 to 0.45; 3 studies, 234 participants; low-certainty evidence; 12 months: -0.27 kPa, 95% CI -0.86 to 0.32, 3 studies; 170 participants; low-certainty evidence). The PaCO2 was reduced by NIV at both three months (AMD -0.40 kPa, 95% CI -0.70 to -0.09; 3 studies, 241 participants; moderate-certainty evidence) and 12 months (AMD -0.52 kPa, 95% CI -0.87 to -0.18; 3 studies, 175 participants; high-certainty evidence). NIV may have little to no benefit on HRQL (3 months: SMD 0.25, 95% CI -0.01 to 0.51; 2 studies, 219 participants; very low-certainty evidence; 12 months: SMD 0.25, 95% -0.06 to 0.55; 2 studies, 164 participants; very low-certainty evidence). Admission-free survival seems improved with NIV (AHR 0.71, 95% CI 0.54 to 0.94; 2 studies, 317 participants; low-certainty evidence), but the risk for all-cause mortality does not seem to improve (AHR 0.97, 95% CI 0.74 to 1.28; 2 studies, 317 participants; low-certainty evidence).AUTHORS' CONCLUSIONS: Regardless of the timing of initiation, chronic NIV improves daytime hypercapnia. In addition, in stable COPD, survival seems to be improved and there might be a short term HRQL benefit. In people with persistent hypercapnia after a COPD exacerbation, chronic NIV might prolong admission-free survival without a beneficial effect on HRQL. In stable COPD, future RCTs comparing NIV to a control group receiving standard care might no longer be warranted, but research should focus on identifying participant characteristics that would define treatment success. Furthermore, the optimal timing for initiation of NIV after a severe COPD exacerbation is still unknown.</p