Recurrent Pneumothorax with CPAP Therapy for Obstructive Sleep Apnea

Prevalence and patient risk factors for pneumothorax in COVID-19 and in influenza pneumonia: a nationwide comparative analysis

Background

Pneumothorax is a rare but deadly complication in patients who require mechanical ventilation. As with any condition associated with acute respiratory distress syndrome (ARDS), coronavirus disease 2019 (COVID-19) is known to be associated with pneumothorax. However, in the literature, comparative data on the risk factors for pneumothorax in COVID-19 and other diseases like influenza are limited. The aim of this study is to determine the prevalence and risk factors for pneumothorax in hospitalized COVID-19 patients and compare them with influenza pneumonia patients.

Methods

This study is a retrospective analysis of the National Inpatient Sample (NIS) 2020 database cohort. Univariate and multivariate logistic regression were used to identify the prevalence and risk factors for pneumothorax in COVID-19 patients and compared with the risk of pneumothorax in influenza patients.

Results

The NIS 2020 database includes 1,608,980 hospitalizations of COVID-19 patients, of which 22,545 [95% confidence interval (CI): 21,491-23,598] (1.4%) developed pneumothorax. On multivariate analysis, factors associated with pneumothorax in COVID-19 included patient age of 41-64 years; male sex; Hispanics, Native Americans, and other races; hospitals with large-bed size; privately owned hospitals; urban teaching hospitals; hospitals in the southern United States (US); stroke; malnutrition; chronic obstructive pulmonary disease (COPD); bronchiectasis; pulmonary fibrosis; liver disease; non-invasive and invasive ventilation; and extracorporeal membrane oxygenation (ECMO). Of 184,980 influenza patients, 1,630 (95% CI: 1,448-1,811) (0.88%) developed pneumothorax. The prevalence of pneumothorax was higher (1.4%) in COVID-19 patients compared to patients with influenza pneumonia (0.88%).

Conclusions

COVID-19 patients who develop pneumothorax have a poor prognosis. Several risk factors for the development of pneumothorax were identified. Patients with these risk factors should be prioritized in applying evidence-based guidelines to prevent pneumothorax.

Continuous positive airway pressure is unsafe for radiofrequency ablation of lung cancer under sedation: a randomised controlled trial

OBJECTIVE

To evaluate the safety of a minimum continuous positive airway pressure of 4 cmH2O (CPAP + 4) during computed tomography (CT)-guided radiofrequency ablation (RFA) for lung malignancies under procedural sedation and analgesia (PSA).

METHODS

This was a prospective, randomised, single-blind, parallel-group, placebo-controlled trial with an open-label medical device conducted at a single tertiary university hospital in Barcelona, Spain. Forty-six patients over 18 years of age scheduled for CT-guided RFA of a malignant pulmonary tumour under PSA were randomised to receive either CPAP + 4 or a modified mask for placebo CPAP (Sham-CPAP). Exclusion criteria included contraindications for RFA, refusal to participate, inability to understand the procedure or tolerate the CPAP test, lung biopsy just prior to RFA, intercurrent diseases, or previous randomisation for additional pulmonary RFA. Primary outcomes were the percentage of patients reporting at least one serious adverse event (SAE), classification for complications from the Cardiovascular and Interventional Radiological Society of Europe (CIRSE), and Clavien-Dindo classifications for complications, hospital stay, and readmissions. Secondary outcomes included adverse events (AEs), respiratory parameters, airway management, and the local radiological efficacy of pulmonary ablation.

RESULTS

CPAP + 4 prolonged hospital stay (1.5 ± 1.1 vs. 1.0 ± 0 inpatient nights, p = 0.022) and increased the risk of AE post-RFA (odds ratio (95% CI): 4.250 (1.234 to 14.637), p = 0.021 with more pneumothorax cases (n = 5/22, 22.7% vs. n = 0/24, 0%, p = 0.019). Per-protocol analysis revealed more SAEs and CIRSE grade 3 complications in the CPAP + 4 group (23.5% vs. 0%, p = 0.036). No significant differences were found in the effectiveness of oxygenation, ventilation, or pulmonary ablation.

CONCLUSION

CPAP is unsafe during CT-guided RFA for lung cancer under PSA even at the lowest pressure setting.

TRIAL REGISTRATION

ClinicalTrials.Gov, ClinicalTrials.gov ID NCT02117908, Registered 11 April 2014, https://www.

CLINICALTRIALS

gov/study/NCT02117908 CRITICAL RELEVANCE STATEMENT: This study highlights the hazards of continuous positive airway pressure during radiofrequency ablation of lung cancer, even at minimal pressures, deeming it unsafe under procedural sedation and analgesia in pulmonary interventional procedures. Findings provide crucial insights to prioritise patient safety.

KEY POINTS

No prior randomised controlled trials on CPAP safety in percutaneous lung thermo-ablation. Standardised outcome measures are crucial for radiology research. CPAP during lung RFA raises hospital stay and the risk of complications. CPAP is unsafe during CT-guided RFA of lung cancer under procedural sedoanalgesia.

CPAP pressure and flow data at 2 positive pressure levels and multiple controlled breathing rates from a trial of 30 adults

OBJECTIVES

A unique dataset of airway flow/pressure from healthy subjects on Continuous Positive Airway Pressure (CPAP) ventilation was collected. This data can be used to develop or validate models of pulmonary mechanics, and/or to develop methods to identify patient-specific parameters which cannot be measured non-invasively, during CPAP therapy. These models and values, particularly if available breath-to-breath in real-time, could assist clinicians in the prescription or optimisation of CPAP therapy, including optimising PEEP settings.

DATA DESCRIPTION

Data was obtained from 30 subjects for model-based identification of patient-specific lung mechanics using a specially designed venturi sensor system comprising an array of differential and gauge pressure sensors. Relevant medical information was collected using a questionnaire, including: sex; age; weight; height; smoking history; and history of asthma. Subjects were tasked with breathing at five different rates (including passive), matched to an online pacing sound and video, at two different levels of PEEP (4 and 7 cmH₂O) for between 50 and 180 s. Each data set comprises ~ 17 breaths of data, including rest periods between breathing rates and CPAP levels.

A review of respiratory manifestations and their management in Ehlers-Danlos syndromes and hypermobility spectrum disorders

BACKGROUND

Ehlers-Danlos Syndromes (EDS) and Hypermobility Spectrum Disorders (HSD) are a heterogeneous group of heritable genetic connective tissue disorders with multiple characteristics including joint hypermobility, tissue fragility, and multiple organ dysfunction. Respiratory manifestations have been described in EDS patients, but have not been systematically characterized. A narrative review was undertaken to describe the respiratory presentations and management strategies of individuals with EDS and HSD.

METHODS

A broad literature search of Medline, Embase, Cochrane Database of Systematic Reviews, and Cochrane CENTRAL was undertaken from inception to November 2020 of all study types, evaluating EDS/ HSD and pulmonary conditions. This narrative review was limited to adult patients and publications in English.

RESULTS

Respiratory manifestations have generally been described in hypermobile EDS (hEDS), classical and vascular EDS subtypes. Depending on EDS subtype, they may include but are not limited to dyspnea, dysphonia, asthma, sleep apnea, and reduced respiratory muscle function, with hemothorax and pneumothorax often observed with vascular EDS. Respiratory manifestations in HSD have been less frequently characterized in the literature, but exertional dyspnea is the more common symptom described. Respiratory symptoms in EDS can have an adverse impact on quality of life. The respiratory management of EDS patients has followed standard approaches with thoracotomy tubes and pleurodesis for pleural manifestations, vocal cord strengthening exercises, continuous positive pressure support for sleep apnea, and exercise training. Reduced respiratory muscle function in hEDS patients responds to inspiratory muscle training.

CONCLUSION

Respiratory symptoms and manifestations are described in EDS and HSD, and have generally been managed using conservative non-surgical strategies. Research into the prevalence, incidence and specific respiratory management strategies in EDS and HSD is needed to mitigate some of the associated morbidity.