BACKGROUND: Home mechanical ventilation (HMV) is the treatment for chronic hypercapnic alveolar hypoventilation. The proportion and evolution of paediatric invasive (IMV) and non-invasive (NIV) HMV across the world is unknown, as well as the disorders and age of children using HMV.
METHODS: Search of Medline/PubMed for publications of paediatric surveys on HMV from 2000 to 2023.
RESULTS: Data from 32 international reports, representing 8815 children (59% boys) using HMV, were analysed. A substantial number of children had neuromuscular disorders (NMD; 37%), followed by cardiorespiratory (Cardio-Resp; 16%), central nervous system (CNS; 16%), upper airway (UA; 13%), other disorders (Others; 10%), central hypoventilation (4%), thoracic (3%) and genetic/congenital disorders (Gen/Cong; 1%). Mean age±SD (range) at HMV initiation was 6.7±3.7 (0.5-14.7) years. Age distribution was bimodal, with two peaks around 1-2 and 14-15 years. The number and proportion of children using NIV was significantly greater than that of children using IMV (n=6362 vs 2453, p=0.03; 72% vs 28%, p=0.048), with wide variations among countries, studies and disorders. NIV was used preferentially in the preponderance of children affected by UA, Gen/Cong, Thoracic, NMD and Cardio-Resp disorders. Children with NMD still receiving primary invasive HMV were mainly type I spinal muscular atrophy (SMA). Mean age±SD at initiation of IMV and NIV was 3.3±3.3 and 8.2±4.4 years (p<0.01), respectively. The rate of children receiving additional daytime HMV was higher with IMV as compared with NIV (69% vs 10%, p<0.001). The evolution of paediatric HMV over the last two decades consists of a growing number of children using HMV, in parallel to an increasing use of NIV in recent years (2020-2023). There is no clear trend in the profile of children over time (age at HMV). However, an increasing number of patients requiring HMV were observed in the Gen/Cong, CNS and Others groups. Finally, the estimated prevalence of paediatric HMV was calculated at 7.4/100 000 children.
CONCLUSIONS: Patients with NMD represent the largest group of children using HMV. NIV is increasingly favoured in recent years, but IMV is still a prevalent intervention in young children, particularly in countries indicating less experience with NIV.

Metabolic alkalosis may lead to respiratory inhibition and increased need for ventilatory support or prolongation of weaning from ventilation for patients with chronic respiratory disease. Acetazolamide can reduce alkalaemia and may reduce respiratory depression.
We searched Medline, EMBASE and CENTRAL from inception to March 2022 for randomised controlled trials comparing acetazolamide to placebo in patients with chronic obstructive pulmonary disease, obesity hypoventilation syndrome or obstructive sleep apnoea, hospitalised with acute respiratory deterioration complicated by metabolic alkalosis. The primary outcome was mortality and we pooled data using random-effects meta-analysis. Risk of bias was assessed using the Cochrane RoB 2 (Risk of Bias 2) tool, heterogeneity was assessed using the I2 value and χ2 test for heterogeneity. Certainty of evidence was assessed using GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) methodology.
Four studies with 504 patients were included. 99% of included patients had chronic obstructive pulmonary disease. No trials recruited patients with obstructive sleep apnoea. 50% of trials recruited patients requiring mechanical ventilation. Risk of bias was overall low to some risk. There was no statistically significant difference with acetazolamide in mortality (relative risk 0.98 (95% CI 0.28 to 3.46); p=0.95; 490 participants; three studies; GRADE low certainty) or duration of ventilatory support (mean difference -0.8 days (95% CI -7.2 to 5.6); p=0.36; 427 participants; two studies; GRADE: low certainty).
Acetazolamide may have little impact on respiratory failure with metabolic alkalosis in patients with chronic respiratory diseases. However, clinically significant benefits or harms are unable to be excluded, and larger trials are required.
CRD42021278757.

The surge in cases of severe COVID-19 has resulted in clinicians triaging intensive care unit (ICU) admissions in places where demand has exceeded capacity. In order to assist difficult triage decisions, clinicians require clear guidelines on how to prioritise patients. Existing guidelines show significant variability in their development, interpretation, implementation and an urgent need for a robust synthesis of published guidance. To understand how to manage which patients are admitted to ICU, and receive mechanical ventilatory support, during periods of high demand during the COVID-19 pandemic, a systematic review was performed. Databases of indexed literature (Medline, Embase, Web of Science, and Global Health) and grey literature (Google.com and MedRxiv), published from 1 January until 2 April 2020, were searched. Search terms included synonyms of COVID-19, ICU, ventilation, and triage. Only formal written guidelines were included. There were no exclusion criteria based on geographical location or publication language. Quality appraisal of the guidelines was performed using the Appraisal of Guidelines for Research and Evaluation Instrument II (AGREE II) and the Appraisal of Guidelines for Research and Evaluation Instrument Recommendation EXcellence (AGREE REX) appraisal tools, and key themes related to triage were extracted using narrative synthesis. Of 1902 unique records identified, nine relevant guidelines were included. Six guidelines were national or transnational level guidance (UK, Switzerland, Belgium, Australia and New Zealand, Italy, and Sri Lanka), with one state level (Kansas, USA), one international (Extracorporeal Life Support Organization) and one specific to military hospitals (Department of Defense, USA). The guidelines covered several broad themes: use of ethical frameworks, criteria for ICU admission and discharge, adaptation of criteria as demand changes, equality across health conditions and healthcare systems, decision-making processes, communication of decisions, and guideline development processes. We have synthesised the current guidelines and identified the different approaches taken globally to manage the triage of intensive care resources during the COVID-19 pandemic. There is limited consensus on how to allocate the finite resource of ICU beds and ventilators, and a lack of high-quality evidence and guidelines on resource allocation during the pandemic. We have developed a set of factors to consider when developing guidelines for managing intensive care admissions, and outlined implications for clinical leads and local implementation.

Acute respiratory failure (ARF) is a common cause of admission to intensive care units (ICUs). Mucoactive agents are medications that promote mucus clearance and are frequently administered in patients with ARF, despite a lack of evidence to underpin clinical decision making. The aim of this systematic review was to determine if the use of mucoactive agents in patients with ARF improves clinical outcomes.
We searched electronic and grey literature (January 2020). Two reviewers independently screened, selected, extracted data and quality assessed studies. We included trials of adults receiving ventilatory support for ARF and involving at least one mucoactive agent compared with placebo or standard care. Outcomes included duration of mechanical ventilation. Meta-analysis was undertaken using random-effects modelling and certainty of the evidence was assessed using Grades of Recommendation, Assessment, Development and Evaluation.
Thirteen randomised controlled trials were included (1712 patients), investigating four different mucoactive agents. Mucoactive agents showed no effect on duration of mechanical ventilation (seven trials, mean difference (MD) -1.34, 95% CI -2.97 to 0.29, I2=82%, very low certainty) or mortality, hospital stay and ventilator-free days. There was an effect on reducing ICU length of stay in the mucoactive agent groups (10 trials, MD -3.22, 95% CI -5.49 to -0.96, I2=89%, very low certainty).
Our findings do not support the use of mucoactive agents in critically ill patients with ARF. The existing evidence is of low quality. High-quality randomised controlled trials are needed to determine the role of specific mucoactive agents in critically ill patients with ARF.
CRD42018095408.

BACKGROUND: Chronic ventilatory failure (CVF) may be associated with reduced exercise capacity. Long-term non-invasive ventilation (NIV) may reduce patients\' symptoms, improve health-related quality of life and reduce mortality and hospitalisations. There is an increasing use of NIV during exercise training with the purpose to train patients at intensity levels higher than allowed by their pathophysiological conditions.
OBJECTIVE: This narrative review describes the possibility to train patients with CVF and NIV use as a tool to increase the benefits of exercise training.
METHODS: We searched papers published between 1985 and 2018 in (or with the summary in) English language in PubMed and Scopus databases using the keywords \"chronic respiratory failure AND exercise,\" \"non invasive ventilation AND exercise,\" \"pulmonary rehabilitation\" and \"exercise training.\"
RESULTS: Exercise training is feasible and effective also in patients with CVF. Assisted ventilation can improve exercise tolerance in different clinical conditions. In patients under long-term home ventilatory support, NIV administered also during walking results in improved oxygenation, decreased dyspnoea and increased walking distance. Continuous positive airway pressure and different modalities of assisted ventilation have been delivered through different interfaces during exercise training programmes. Patients with CVF on long-term NIV may benefit from exercising with the same ventilators, interfaces and settings as used at home.
CONCLUSIONS: We need more randomised clinical trials to investigate the effects of NIV on exercise training in patients with CVF and define organisation and setting.