The use of thrombolytics in the management of complex pleural fluid collections

A Novel Rabbit Model of Retained Hemothorax with Pleural Organization

Retained hemothorax (RH) is a commonly encountered and potentially severe complication of intrapleural bleeding that can organize with lung restriction. Early surgical intervention and intrapleural fibrinolytic therapy have been advocated. However, the lack of a reliable, cost-effective model amenable to interventional testing has hampered our understanding of the role of pharmacological interventions in RH management. Here, we report the development of a new RH model in rabbits. RH was induced by sequential administration of up to three doses of recalcified citrated homologous rabbit donor blood plus thrombin via a chest tube. RH at 4, 7, and 10 days post-induction (RH4, RH7, and RH10, respectively) was characterized by clot retention, intrapleural organization, and increased pleural rind, similar to that of clinical RH. Clinical imaging techniques such as ultrasonography and computed tomography (CT) revealed the dynamic formation and resorption of intrapleural clots over time and the resulting lung restriction. RH7 and RH10 were evaluated in young (3 mo) animals of both sexes. The RH7 recapitulated the most clinically relevant RH attributes; therefore, we used this model further to evaluate the effect of age on RH development. Sanguineous pleural fluids (PFs) in the model were generally small and variably detected among different models. The rabbit model PFs exhibited a proinflammatory response reminiscent of human hemothorax PFs. Overall, RH7 results in the consistent formation of durable intrapleural clots, pleural adhesions, pleural thickening, and lung restriction. Protracted chest tube placement over 7 d was achieved, enabling direct intrapleural access for sampling and treatment. The model, particularly RH7, is amenable to testing new intrapleural pharmacologic interventions, including iterations of currently used empirically dosed agents or new candidates designed to safely and more effectively clear RH.

Retrospective review comparing intrapleural fibrinolytic therapy (alteplase) and surgical intervention in complex pleural effusion

Background

Intrapleural fibrinolytic therapy (IPFT) is one of the treatment options for complex pleural effusion. In this study, the IPFT agent used was alteplase, a tissue plasminogen activator (t-PA). This study aims to determine the difference in the outcome of patients with complex pleural effusion between IPFT and surgery in terms of radiological improvement, inflammatory parameters, length of stay, and post-intervention complications.

Methods

A retrospective review of patients with complex pleural effusion treated at Universiti Kebangsaan Malaysia Medical Center from January 2012 to August 2020 was performed. Patient demographics, chest imaging, drainage chart, inflammatory parameters, length of hospital stay, and post-intervention and outcome were analyzed.

Results

Fifty-eight patients were identified (surgical intervention, n = 18; 31% and IPFT, n = 40, 69%). The mean age was 51.7 ± 18.2 years. Indication for surgical intervention was pleural infection (n = 18; 100%), and MPE (n = 0). Indications for IPFT was pleural infection (n = 30; 75%) and MPE (n = 10; 25%). The dosages of t-PA were one to five doses of 2–50 mg. The baseline chest radiograph in the IPFT group was worse than in the surgical intervention group. (119.96 ± 56.05 vs. 78.19 ± 55.6; p = 0.029) At week 1, the radiological success rate for IPFT and surgical intervention were 27% and 20%, respectively, and at weeks 4–8, the success rate was 56% and 80% respectively. IPFT was associated with lesser complications; fever (17.5%), chest pain (10%), and non-life-threatening bleeding (5%).

Conclusion

IPFT was comparable to surgery in radiological outcome, inflammatory parameters, and length of stay with lesser reported complications.

Retrospective Evaluation of Intrapleural Tissue Plasminogen Activator With or Without Dornase Alfa for the Treatment of Traumatic Retained Hemothorax: A 6-Year Experience

BACKGROUND

Intrapleural fibrinolytic instillation is second-line treatment for retained hemothorax. Dornase alfa (DNase) has demonstrated efficacy in parapneumonic effusion, but the lack of deoxyribonucleoproteins limits direct extrapolation to traumatic retained hemothorax treatment.

OBJECTIVE

This study evaluated the effectiveness of intrapleural tissue plasminogen activator (tPA) with and without DNase in the treatment of retained traumatic hemothorax.

METHODS

This retrospective cohort study included patients aged 16 years and older admitted to a level 1 trauma center from January 2013 through July 2019 with retained hemothorax and one or more intrapleural tPA instillations. Exclusion criteria were tPA for other indications or concomitant empyema. The primary endpoint was treatment failure defined as the need for operative intervention.

RESULTS

Fifty patients were included (tPA alone: 28; tPA with DNase: 22). Baseline characteristics were similar between groups, including time to diagnosis (6.5 [interquartile range (IQR), 4-15.5] days vs 6 [IQR, 6.3-10.8] days, P = 0.52). Median tPA dose per treatment (6 [IQR, 6-6.4] mg vs 10 [IQR, 8.4-10] mg, P < 0.001) and cumulative tPA (18 [IQR, 6.5-24] mg vs 30 [IQR, 29.5-40], P < 0.001) dose were significantly lower in the tPA alone group. Treatment failure was similar between groups. Chest tube output, retained hemothorax reduction, and bleeding incidences were similar between groups. Multivariate logistic regression demonstrated no significant risk factors for treatment failure.

CONCLUSIONS AND RELEVANCE

Dornase alfa added to tPA may not reduce the need for operation to treat retained hemothorax. Further studies should be directed at optimal tPA dose determination and economic impact of inappropriate DNase use.

From Bedside to the Bench—A Call for Novel Approaches to Prognostic Evaluation and Treatment of Empyema

Empyema, a severe complication of pneumonia, trauma, and surgery is characterized by fibrinopurulent effusions and loculations that can result in lung restriction and resistance to drainage. For decades, efforts have been focused on finding a universal treatment that could be applied to all patients with practice recommendations varying between intrapleural fibrinolytic therapy (IPFT) and surgical drainage. However, despite medical advances, the incidence of empyema has increased, suggesting a gap in our understanding of the pathophysiology of this disease and insufficient crosstalk between clinical practice and preclinical research, which slows the development of innovative, personalized therapies. The recent trend towards less invasive treatments in advanced stage empyema opens new opportunities for pharmacological interventions. Its remarkable efficacy in pediatric empyema makes IPFT the first line treatment. Unfortunately, treatment approaches used in pediatrics cannot be extrapolated to empyema in adults, where there is a high level of failure in IPFT when treating advanced stage disease. The risk of bleeding complications and lack of effective low dose IPFT for patients with contraindications to surgery (up to 30%) promote a debate regarding the choice of fibrinolysin, its dosage and schedule. These challenges, which together with a lack of point of care diagnostics to personalize treatment of empyema, contribute to high (up to 20%) mortality in empyema in adults and should be addressed preclinically using validated animal models. Modern preclinical studies are delivering innovative solutions for evaluation and treatment of empyema in clinical practice: low dose, targeted treatments, novel biomarkers to predict IPFT success or failure, novel delivery methods such as encapsulating fibrinolysin in echogenic liposomal carriers to increase the half-life of plasminogen activator. Translational research focused on understanding the pathophysiological mechanisms that control 1) the transition from acute to advanced-stage, chronic empyema, and 2) differences in outcomes of IPFT between pediatric and adult patients, will identify new molecular targets in empyema. We believe that seamless bidirectional communication between those working at the bedside and the bench would result in novel personalized approaches to improve pharmacological treatment outcomes, thus widening the window for use of IPFT in adult patients with advanced stage empyema.

Empyema Versus Lung Abscess: A Case Report

Lung abscesses and empyemas are 2 forms of pulmonary infection that can present with similar clinical features. However, empyemas are associated with higher morbidity and mortality, necessitating the need to distinguish one from the other. Plain radiographs can sometimes provide clues to help differentiate the 2 pathologies but more often than not, a computed tomography scan is required to confirm the diagnosis. Correct diagnosis is essential, as the goal standard therapeutic intervention for empyemas may be contraindicated in patients with lung abscesses. Empyemas require percutaneous or surgical drainage in combination with antibiotics, while lung abscesses are generally treated with antibiotics alone as drainage can be associated with various complications. We present a case of a 65-year-old man with parapneumonic empyema diagnosed with characteristic findings on chest computed tomography and treated with surgical drainage and antibiotics. We hope to improve patient outcomes by highlighting the classical radiographic findings that help distinguish empyema and abscess.

Challenges in Image-Guided Drainage of Infected Pleural Collections: A Review

Infected pleural fluid collections (IPFCs) commonly occur as a part of bacterial, fungal, or tubercular pneumonia or due to involvement of pleura through hematogenous route. Management requires early initiation of therapeutic drugs, as well as complete drainage of the fluid, to relieve patients’ symptoms and prevent pleural fibrosis. Image-guided drainage plays an important role in achieving these goals and improving outcomes. Intrapleural fibrinolytic therapy (IPFT) is also a vital component of the management. The concepts of image-guided drainage procedures, IPFT, and nonexpanding lung are discussed in this review.

Short and long-term outcomes of surgical intervention for empyema in the post-fibrinolytic era

BACKGROUND

Open window thoracostomy (OWT) is indicated for patients with bronchopleural fistula (BPF) or trapped lung in the setting of empyema refractory to non-surgical interventions. We investigated the role of OWT in the era of minimally invasive surgeries, endobronchial valves and fibrinolytic therapy.

METHODS

A retrospective chart review of all patients who underwent OWT at a single institution from 2010 to 2020 was performed. Indications for the procedure as well as operative details and morbidity and mortality were evaluated to determine patient outcomes for OWT.

RESULTS

Eighteen patients were identified for the study. The most common indication for OWT was post-resectional BPF (n = 9). Prior to OWT, n = 11 patients failed other surgical or minimally invasive interventions. Patient comorbidities were quantified with the Charlson Comorbidity index (n = 11 score ≥ 5, 10-year survival ≤21%). Three (16.7%) patients died < 30 days post-operatively and 12 (66%) patients were deceased by the study's end (overall survival 24.0 ± 32.2 months). Mean number of ribs resected were 2.5 ± 1.2 (range 1-6) with one patient having 6 ribs removed. Patients were managed with negative pressure wound therapy (n = 9) or Kerlix packing (n = 9). Eleven patients (61.6%) underwent delayed closure (mean time from index surgery to closure 4.8 ± 6.7 months).

CONCLUSIONS

Our study illustrates the significant comorbidities of patients undergoing OWT, the poor outcomes therein, and pitfalls associated with this procedure. We show that negative pressure wound therapy can be utilized as potential way to obliterate the pleural space and manage an open chest in the absence of an airleak; however, OWT procedures continue to be extremely morbid.

Recurrent Large Volume Malignant Pleural Effusion in a Patient With Renal Cell Carcinoma

Malignant pleural effusion (MPE) due to renal cell carcinoma (RCC) is extremely rare, accounting for only 1%-2% of all malignant pleural effusions. This paper presents a case report of a 56-year-old male who presented with a chief complaint of bilateral flank pain with dyspnea and was diagnosed with RCC via immunopathologic pleural fluid analysis and who persistently had recurrent large volume pleural effusion.

A 56-year-old male who had a recent admission for dyspnea secondary to a right-sided pleural effusion underwent thoracentesis and returned to the hospital for his worsening shortness of breath. He was found to have recurrent pleural effusion. Thoracentesis studies revealed an exudative pleural effusion positive for malignant cells showing adenocarcinoma, which had an immunopathologic profile (WT-1 and PAX8) favoring an adenocarcinoma of kidney origin. The patient underwent chest tube placement, followed by chemical pleurodesis with 4.3 L of bloody fluid drained immediately. Subsequent x-rays taken while the chest tube was in place showed worsening reaccumulating pleural effusion. A repeat CT scan showed a large right pleural effusion with loculated collections. The patient then underwent right video-assisted thoracoscopic surgery, which revealed a loculated effusion with pleural carcinomatosis that was biopsy-positive for RCC.

This report presents a rare case displaying how RCC pleural carcinomatosis can cause a patient to present with dyspnea secondary to a pleural effusion, which was revealed to be RCC upon fluid cytology and immunohistopathology studies. This case demonstrates that RCC can cause recurrent large volume MPE, which has not been widely reported in contemporary literature.

Use of fibrinolytics and deoxyribonuclease in adult patients with pleural empyema: a consensus statement

Although our understanding of the pathogenesis of empyema has grown tremendously over the past few decades, questions still remain on how to optimally manage this condition. It has been almost a decade since the publication of the MIST2 trial, but there is still an extensive debate on the appropriate use of intrapleural fibrinolytic and deoxyribonuclease therapy in patients with empyema. Given the scarcity of overall guidance on this subject, we convened an international group of 22 experts from 20 institutions across five countries with experience and expertise in managing adult patients with empyema. We did a literature and internet search for reports addressing 11 clinically relevant questions pertaining to the use of intrapleural fibrinolytic and deoxyribonuclease therapy in adult patients with bacterial empyema. This Position Paper, consisting of seven graded and four ungraded recommendations, was formulated by a systematic and rigorous process involving the evaluation of published evidence, augmented with provider experience when necessary. Panel members participated in the development of the final recommendations using the modified Delphi technique. Our Position Paper aims to address the existing gap in knowledge and to provide consensus-based recommendations to offer guidance in clinical decision making when considering the use of intrapleural therapy in adult patients with bacterial empyema.

Intrapleural Tissue Plasminogen Activator for Traumatic Retained Hemothorax

Objective: To describe the efficacy, safety, dosing regimen, and administration technique of intrapleural alteplase for the treatment of retained hemothorax. Data Sources: A PubMed, EMBASE, and Google Scholar search (January 2000 to February 2019) was conducted with the search terms intrapleural, fibrinolytic, fibrinolysis, alteplase, tissue plasminogen activator, and hemothorax. Study Selection and Data Extraction: Articles were included if they described the use of intrapleural alteplase in adult patients with a retained hemothorax; single patient case reports and abstracts were excluded. Data Synthesis: A total of 6 retrospective reviews and 1 meta-analysis were identified for inclusion. A variety of dosing strategies have been defined for the administration of intrapleural alteplase ranging from 6 to 100 mg, volume of fluid from 50 to 120 mL of normal saline, and the number of total doses has ranged from 1 to 8 over the treatment course. A majority of studies showed a greater than 80% success rate and less than 7% bleeding rate. Relevance to Patient Care and Clinical Practice: Because of the paucity of data for use of alteplase in retained hemothorax and administration of a high-risk medication, this review provides dosing and administration recommendations based on reported safety and efficacy. Conclusion: Administration of intrapleural alteplase should be considered in patients with retained hemothorax as an alternative to surgical intervention. In contrast to intrapleural alteplase administration for other indications such as empyema, higher doses and volumes of alteplase are recommended for retained hemothorax.

A systematic review of comorbidities and outcomes of adult patients with pleural infection

Background

Pleural infection remains an important cause of mortality. This study aimed to investigate worldwide patterns of pre-existing comorbidities and clinical outcomes of patients with pleural infection.

Methods

Studies reporting on adults with pleural infection between 2000 and 2017 were identified from a search of Embase and MEDLINE. Articles reporting exclusively on tuberculous, fungal or post-pneumonectomy infection were excluded. Two reviewers assessed 20 980 records for eligibility.

Results

211 studies met the inclusion criteria. 134 articles (227 898 patients, mean age 52.8 years) reported comorbidity and/or outcome data. The majority of studies were retrospective observational cohorts (n=104, 78%) and the most common region of reporting was East Asia (n=33, 24%) followed by North America (n=27, 20%). 85 articles (50 756 patients) reported comorbidity. The median (interquartile range (IQR)) percentage prevalence of any comorbidity was 72% (58–83%), with respiratory illness (20%, 16–32%) and cardiac illness (19%, 15–27%) most commonly reported. 125 papers (192 298 patients) reported outcome data. The median (IQR) length of stay was 19 days (13–27 days) and median in-hospital or 30-day mortality was 4% (IQR 1–11%). In regions with high-income economies (n=100, 74%) patients were older (mean 56.5 versus 42.5 years, p<0.0001), but there were no significant differences in prevalence of pre-existing comorbidity nor in length of hospital stay or mortality.

Conclusion

Patients with pleural infection have high levels of comorbidity and long hospital stays. Most reported data are from high-income economy settings. Data from lower-income regions is needed to better understand regional trends and enable optimal resource provision going forward.

In pleural infection, patients from higher-income countries tend to be older with more comorbidities and are more likely to be referred for fibrinolytic treatment in comparison to patients from lower-income countrieshttp://bit.ly/2K2M5HL