CFDB - Cystic Fibrosis DataBase

Bronchopulmonary complications therapy

Pneumothorax in cystic fibrosis

Background

Spontaneous Pneumothorax (PNX), a potentially life-threatening complication for people with CF (Mingora CM, Flume PA,2021) characterized by the presence of air in the pleural space. Structural impairment and altered airflow dynamics in the lungs of CF patients are considered as the main predisposing factors, but also inhaled medications and non-invasive positive pressure ventilation (NIPPV) could increase the risk of pneumothorax (Kioumis IP et al, 2014). Its annual incidence is estimated at 0.64% according to US registry data, with a lifetime risk of 3.4%, with an incidence increasing proportionally with age and disease severity, as well as with the presence in sputum of Pseudomonas aeruginosa (PA), Burkholderia cepacia (BC), Aspergillus fumigatus (AF). Clinical presentation could range from dramatic to very mild.The majority of people present clinical symptoms such as chest pain or breathlessness and on rare occasions respiratory failure, although pneumothoraces may occasionally be asymptomatic. Cysts, blebs and bullae are all commonly identified in the lungs of CF as risk factors. Generally PNX is associated with a higher morbidity and mortality in the two years following the clinical manifestation. Spontaneous PNX is defined as recurrent when it occurs on the same side seven days or more after resolution of the first episode, or persistent if the air leak lasts for more than five days. Diagnosi is based on clinical symptoms and imaging (CT scan). Recently (Dietrich CF, 2021) ultrasound (US) has been discussed by World Federation of Societies for Ultra-sound in Medicine and Biology (WFUMB) as a  diagnostic tool for paediatric patients with  pneumothorax. 

In adults with CF (King CS et al, 2019) pneumothorax  occurs in 72.4%. Severe airway obstruction, colonization with Pseudomonas, Burkholderia species, and Aspergillus, allergic bronchopulmonary aspergillosis, pancreatic insufficiency, and need for a feeding tube are risk factors or pneumothorax.

Cystic Fibrosis Pulmonary Guidelines for Pulmonary Complications (Flume PA et al, 2010) and a review (Flume PA et al, 2011) have been previously published to help clinicians to define how a PNX should be monitored. Many years ago (Diso D et al, 2013) a single-center longitudinal survey on 101 patients with CF and bilateral lung transplantation showed that PNX could be an additional risk factor for perioperative mortality.

In CF spontaneous PNX therapy is a still controversial issue and there are no standard treatments (Lord RW et al, 2016)).Management of spontaneous pneumothorax occurring to patients with CF is essentially similar to that for non-CF patients.  Either medical or surgical interventions represent two options for acute or recurrent PNX therapy. While surgical interventions are felt to be more effective in people without CF, complications directly related to this procedure, as well as post-operative complications, make surgical interventions at higher risk in patients with CF. Additionally, it is also debated whether these interventions make people with CF ineligible for lung transplantation in the future. No systematic reviews are available assessing both clinical efficacy and safety of different interventions for persistent PNX.

A report of the European Respiratory Society/European Cystic Fibrosis Society task force on the care of adults with CF (Elborn JS et al, 2016) outlined the relevance of respiratory physicians adequately trained in CF management of complications such as PNX. However, guidelines are unable to cover all aspects of this complication, as previously  reviewed (Lord RW et al, 2016).

Issues

To evaluate both benefits and side effects or disadvantages for surgical and non-surgical treatments of persistent and recurrent PNX in people with CF.

What is known

Only one CDSR (Amin R et al, 2012) has been published to compare the use of chemical pleurodesis by quinacrine, silver nitrate, talc or tetracycline derivatives with surgical interventions, including open thoracotomy or video assisted thoracoscopic surgery (VATS) for pleurodesis in recurrent and persistent PNX. No RCTs have been found on this topic.

While the choice of sclerosing agents, as well as the ideal dose and technique of administration, remains variable in clinical practice for medical intervention, limitations of sclerosant instillation procedure mainly include prolonged pleural drainage and unequal deposition, resulting in incomplete pleurodesis. In particular, talc results in more systemic inflammation and its use is a relative contraindication for lung transplantation in people with CF.

On the other hand, up to now clinicians have no sufficient data showing whether surgical interventions, primarily including open thoracotomy, pleurectomy and resection, electrocautery or laser ablation of a bleb or bullae, could be the most effective way for treating PNX.

Unresolved questions

There is no consensus on the agent which should be used for pleurodesis in people with CF, when applicable, neither what surgical intervention is more effective.

Multi-centered RCTs mainly designed to explore the optimal management strategy for spontaneous and persistent PNX in people with CF aimed at evaluating recurrence of PNX as primary outcome, and length of hospitalization and adverse events as secondary outcomes are still missing . Besides the need of RCTs, ethical issues make very difficult to design clinical trials studies and draw the appropriate conclusions. So clinicians must make an individual choice of intervention for each patient (Lord RW et al, 2016).

Keywords: Pneumothorax;