The future of chemical pleurodesis: A review of novel and investigational sclerosant agents

Chemical pleurodesis is a technique in which an injurious and inflammatory substance is instilled into the pleural cavity to cause adhesion and fibrosis. It is commonly used in the management of recurrent malignant pleural effusions. Historically, many different types of sclerosants have been described, though only a few, including talc, the tetracycline derivatives, and anti-septic compounds such as silver nitrate and iodopovidone, have found their way into mainstream use. However, over the past several years, there has been increasing interest in alternative pleurodesis agents. In this review, we will explore future directions in the field, with an eye toward novel and investigational agents.

Intraoperative OK-432 pleurodesis for preventing recurrence of primary spontaneous pneumothorax in children and adolescents: a single-center experience

BACKGROUND

Primary spontaneous pneumothorax (PSP) commonly occurs in lean, tall, male children and adolescents. To reduce recurrence rates of PSP, chemical pleurodesis could be helpful for patients undergoing video-assisted thoracoscopic surgery (VATS) wedge bullectomy. The efficacy and safety of intraoperative OK-432 (Picibanil) pleurodesis on preventing the recurrence of PSP in pediatric patients remain unclear.

METHODS

It is a retrospective observational study in a single center, between 2014 and 2020, enrolled 48 (8 females) pediatric PSP patients with persistent air leakage at the mean age of 16.3 ± 1.1 years to receive VATS wedge bullectomy and pleural abrasion. Twenty patients received additional intraoperative OK-432 pleurodesis. The clinical characteristics of patients, surgical outcomes, and recurrence rates were analyzed.

RESULTS

The OK-432 group had longer operation time (118.6 ± 35.6 vs. 96.5 ± 23.3 min; p < 0.05) and higher proportion of postoperative fever (75.0% vs. 28.5%; p = 0.015) than the standard group. No serious adverse events were noted and other surgical outcomes in the two groups were comparable. After a mean follow-up period of 18.1 ± 19.1 months, the OK-432 group had a lower recurrence rate compared with the standard group (5% vs. 28.6%; p < 0.05, odds ratio 0.13, 95% confidence interval: 0.01-1.15), but it had no significant difference in statistics on the Kaplan-Meier curves (log-rank p = 0.105).

CONCLUSION

It was the first study that focused on the addition of intraoperative OK-432 pleurodesis for PSP with persistent air leakage in children and adolescents receiving VATS. It demonstrated the efficacy with a low recurrence rate and short-term safety as a single-center experience.

LEVEL OF EVIDENCE

Retrospective review, therapeutic study, Level III.

A multidirectional two-tube method for chemical pleurodesis could improve distribution of the sclerosing agent within the pleural cavity - A pilot study

Introduction

Malignant pleural effusion (MPE) affects approximately 200,000 people in the United States per annum. Chemical pleurodesis is a recommended first line treatment in the management of MPE, however, success rates as low as 43% has been reported. A bedside chemical pleurodesis can cost up to $11,224 and an estimated inpatient annual expenditure of more than $5 billion in the US alone. This study aims to assess the distribution of the talc slurry within the pleural space using human cadaveric models and to determine the force required to push the talc slurry though a 14 Fr chest tube.

Materials and methods

The force required to administer the talc slurry through a 14 Fr chest tube was tested using a Zwick/Roelle Z005 mechanical tester, using a porcine thoracic biomodel. Talc slurry distribution within the pleural cavity was assessed by direct visualisation following administration to the human cadaveric models using single and multidirectional two-tube methods.

Results

Maximum force required to push the talc slurry through a 14 Fr chest tube was 11.36 N ± 2.79 N. Distribution of the talc slurry within the pleural cavity was found to be poor with a single tube method. Multidirectional two-tube method of administration showed more even distribution.

Conclusion

The experimental multidirectional two-tube method results in wider distribution of the talc slurry within the pleural cavity and could further improve success rate of the talc pleurodesis.

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Yearly, there are over 150,000 new cases of MPE in the US alone.

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Success rate of talc pleurodesis as low as 43% has been reported.

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Doctor's hand grip strength does not affect the talc distribution within the pleural cavity.

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Bedside multidirectional two-tube method may improve the success rate of talc slurry pleurodesis.

Risk factors for recurrent spontaneous pneumothorax: A population level analysis

BACKGROUND

We sought to determine the rate and risk factors of recurrent spontaneous pneumothorax in a diverse population.

METHODS

Cohort study using the California Public Discharge Data file (1995-2010). We identified patients with first-time spontaneous pneumothorax. The primary outcome was recurrent pneumothorax. Associations with clinical, patient, and hospital characteristics were assessed using Cox regression analysis.

RESULTS

Among 14,609 patients with a first-time episode of spontaneous pneumothorax, 26.2% developed a recurrence. Risk factors included age <35 (Hazard Ratio [HR] 1.24 95%-Confidence Interval [CI] 1.14-1.36), Asian race (HR 1.24, CI 1.13-1.37), and tube thoracostomy (HR 1.2, CI 1.15-1.31). Mechancial pleurodesis (HR 0.37 CI 0.31-0.45) was superior to chemical pleurodesis (HR 0.71 CI 0.58-0.86) in reducing recurrence risk.

CONCLUSIONS

The risk of recurrent pneumothorax is greatest in patients age <35, Asians, and those requiring a tube thoracostomy. The risks of operative intervention should be balanced against patient risk for recurrence.

Talc pleurodesis in malignant pleural effusion: a systematic review and meta-analysis

OBJECTIVE

Malignant pleural effusion is a severe and common complication in patients with primary or metastatic malignancies of the pleura. Although talc pleurodesis is widely used for managing malignant pleural effusions, there is still controversy in the literature regarding its superiority compared to other approaches. We conducted this meta-analysis to further investigate its efficacy compared to alternative interventions.

METHODS

We systematically reviewed the PubMed, Cochrane, and Scopus databases to identify studies that fulfilled our inclusion criteria. Study quality was evaluated using validated tools and the pooled Risk Ratio (RR) and confidence interval (CI) were calculated. We performed sensitivity analyses based on the meta-analysis method and type of study.

RESULTS

Twenty-four studies were included in the current systematic review meta-analysis. Talc pleurodesis was associated with statistically significant higher successful pleurodesis rates when compared with all controls [RR (95% CI) 1.15 (1.00, 1.31); P_z = 0.04], only chemical controls [RR (95% CI) 1.26 (1.13, 1.40); P_z < 0.0001], and bleomycin [RR (95% CI) 1.22 (1.05, 1.42); P_z = 0.008]. The comparison between talc pleurodesis and controls at the > 1-month follow-up time point favored talc pleurodesis [RR (95% CI): 1.62 (1.15, 2.27); P_z = 0.005]. Finally, talc poudrage was associated with a statistically significant higher successful pleurodesis rate when compared with all controls. Sensitivity analyses verified the robustness of our results.

CONCLUSION

Talc pleurodesis is an effective MPE management approach presenting borderline statistically significant superiority compared to control methods especially compared to bleomycin as well as when pleurodesis success is evaluated later than 1 month postoperatively.

Viscum pleurodesis is as effective as talc pleurodesis and tends to have less adverse effect

PURPOSE

Many patients diagnosed with advanced cancer have malignant pleural effusion that does not respond to chemotherapy or radiation therapy. These patients often have respiratory symptoms, especially dyspnea. In order to relieve these symptoms, various procedures including chemical pleurodesis have been performed. Although talc is the most widely used and effective sclerosing agent, there it has various adverse effects. The objective of this study was to determine whether Viscum (ABNOVA Viscum® Fraxini Injection, manufactured by ABNOVA GmbH, Germany) could be used as an agent to replace talc in clinical practice.

METHODS

Data of 56 patients with malignant pleural effusion who received chemical pleurodesis after tube thoracostomy from January 2003 to December 2017 were retrospectively reviewed to analyze clinical course and response after pleurodesis with each agent.

RESULTS

After pleurodesis, changes in numeric rating scale (NRS) was 1.4 ± 1.6 in the talc group and 0.5 ± 1.5 in the Viscum group (p = 0.108). Changes in white blood cell counts after pleurodesis were 4154.8 ± 6710.7 in the talc group and 3487.3 ± 6067.7 in the Viscum group (p = 0.702). Changes in C-reactive protein (CRP) were 9.03 ± 6.86 in the talc group and 6.3 ± 7.5 in the Viscum group (p = 0.366). The success rate of pleurodesis was 93.3% in the talc group and 96% in the Viscum group (p = 0.225).

CONCLUSION

Viscum pleurodesis showed comparable treatment results with talc pleurodesis while its adverse effects such as chest pain and fever tended to be relatively weak.

First successful case of chemical pleurodesis with oxytetracycline through Rocket® Pleural Vent™: ambulatory pneumothorax device for pneumothorax

A 79-year-old woman with asthma and idiopathic pulmonary fibrosis was admitted for a first episode right apical secondary spontaneous pneumothorax. Due to a lack of pleural separation inside the safety triangle, Rocket® Pleural Vent™ was inserted in the second intercostal space, mid-clavicular line, as guided by thoracic ultrasound. Although the lung fully re-expanded the next day, there was persistent air leak and so chemical pleurodesis with oxytetracycline was performed with success. There was no recurrence of pneumothorax and the patient was discharged two days afterwards, and a follow-up X-ray taken eight months later did not reveal any recurrence of the right-sided pneumothorax. This is the first reported case of successful chemical pleurodesis through Rocket® Pleural Vent™ for pneumothorax, which may serve to provide additional alternatives to the management of secondary spontaneous pneumothorax that is indicated for pleurodesis after lung re-expansion.

Chemical pleurodesis with autologous blood and freeze-dried concentrated human thrombin improved spontaneous pneumothorax and thoracic endometriosis: The first case involving a pregnant woman

OBJECTIVE

Spontaneous pneumothorax combined with thoracic endometriosis is a rare condition during pregnancy. We present a case of chemical pleurodesis with autologous blood and freeze-dried concentrated human thrombin during pregnancy.

CASE REPORT

This report presents a case of spontaneous pneumothorax combined with thoracic endometriosis that arose at 22 weeks' gestation in a 35-year-old female. The initial chest drainage was unsuccessful. At 25 weeks' gestation, video-assisted thoracoscopic surgery was performed and revealed endometriosis in the thoracic cavity. Since the leak persisted, chemical pleurodesis was performed with autologous blood and freeze-dried concentrated human thrombin at 28 weeks' gestation. The leak improved markedly and did not recur.

CONCLUSION

This is the first case report about chemical pleurodesis with autologous blood and freeze-dried concentrated human thrombin during pregnancy. This procedure might contribute to the management of pneumothorax in pregnant women.

The management of chemical pleurodesis with viscum album in patients with persistent air leakage

Background

Persistent air leak (PAL) after major pulmonary resection or involved with secondary lung disease is prevalent and associated with significant morbidity. Chemical pleurodesis is a practical therapeutic tool to manage the patients with PAL. Among various sclerosing substances, viscum album (fraxini) is considered effective and safe. The aim of this study was to evaluate the efficacy and safety of viscum album pleurodesis in patients with intractable prolonged air leakage.

Methods

Between February 2013 and February 2015, 73 consecutive patients who underwent pleurodesis due to PAL were enrolled in this study. Pleurodesis was performed using 100 mg of viscum album (fraxini) at 1 time through the indwelling chest tube. Main studied outcomes were focused on success rate of pleurodesis assessed on chest radiography and cessation of the air leak after procedure.

Results

The study population was predominantly male (n=64, 87.7%). The overall success rate was 90.4%. One patient died of pneumonia not related to the viscum album pleurodesis. The mean length of stoppage to air leakage was 28.00±22.19 hours. The mean duration of chest tube drainage after pleurodesis was 2.78±1.35 days. The mean number of pleurodesis was 1.38±0.75. Thirty-six patients (49.3%) complained of chest pain requiring a prescription for pain control. There were no major relevant complications or mortalities.

Conclusions

Air leaks remain an important cause of morbidity. This viscum album pleurodesis could be considered as an option for the treatment of prolonged air leak patients, associated with acceptable side effects.

Pleurodesis with povidone-iodine for refractory chylothorax in newborns: Personal experience and literature review

INTRODUCTION

Refractory chylothorax is a severe clinical issue, particularly in neonates. Conventional primary approach is based on diet with medium-chain fatty acids and/or total parenteral nutrition. In nonresponders, proposed second line treatments include chemical or surgical pleurodesis, thoracic duct ligation, pleuroperitoneal shunting and pleurectomy but none of these have been shown to be superior to other in terms of resolution rate and safety. Our aim is to report our experience on povidone-iodine use for chemical pleurodesis in newborn infants with chylothorax unresponsive to conservative treatment. Our aim is to report our experience on povidone-iodine use for chemical pleurodesis in newborn infants with chylothorax unresponsive to conservative treatment.

METHODS

Since 2013, povidone-iodine pleurodesis was attempted in all patients with persistent chylothorax who failed conservative treatment (no response to at least 10 days of total parenteral nutrition and maximum dosage of intravenous octreotide). Pleurodesis consisted in the injection of 2 ml/kg of a 4% povidone-iodine solution inside the pleural space, leaving the pleural tube clamped for the subsequent 4 hours.

RESULTS

Five patients were treated with chemical pleurodesis of persistent chylothorax. Four of 5 patients had their pleural effusion treated by one single povidone-iodine infusion. Median time for resolution was 4 days. A patient with massive superior vena cava thrombosis did not benefit from pleurodesis. None of the patients experienced long term side effects of the treatment.

CONCLUSION

Our data suggest that povidone-iodine pleurodesis may be considered a safe and effective option to treat refractory chylothorax in newborns.