Intra-pleural fibrinolytic therapy versus placebo, or a different fibrinolytic agent, in the treatment of adult parapneumonic effusions and empyema

Intrapleural Fibrinolysis with Urokinase versus Alteplase in Complicated Pleural Effusions and Empyema: A Prospective Randomized Controlled Trial

BACKGROUND

Intrapleural fibrinolytic therapy (IPFT) has been used as an effective agent since 1949 for managing complicated pleural effusion and empyema. Several agents, such as streptokinase, urokinase (UK), and recombinant tissue plasminogen activator (rt-PA), have been found to be effective with variable effectiveness. However, a head-tohead controlled trial comparing the efficacy of the most frequently used agents, i.e., UK and rt-PA (alteplase) for managing complicated pleural effusion has rarely been reported.

METHODS

A total of 50 patients were randomized in two intervention groups, i.e., UK and rt-PA. The dose of rt-PA was 10 mg, and that of UK was 1.0 lac units. UK was given thrice daily for 2 days, followed by clamping to allow the retainment of drugs in the pleural space for 2 hours. rt-PA was instilled into the pleural space twice daily for 2 days, and intercostal drainage was clamped for 1 hour.

RESULTS

A total of 50 patients were enrolled into the study, of which 84% (n=42) were males and 16% (n=8) were females. Among them, 30 (60%) patients received UK, and 20 (40%) patients received alteplase as IPFT agents. The percentage of mean± standard deviation changes in pleural opacity was -33.0%±9.9% in the UK group and -41.0%±14.9% in the alteplase group, respectively (p=0.014). Pain was the most common adverse side effect, occurring in 60% (n=18) of the patients in the UK group and in 40% (n=8) of the patients in the alteplase group (p=0.24), while fever was the second most common side effect. Patients who reported early (within 6 weeks of onset of symptoms) showed a greater response than those who reported late for the intervention.

CONCLUSION

IPFT is a safe and effective option for managing complicated pleural effusion or empyema, and newer agents, such as alteplase, have greater efficacy and a similar adverse effect profile when compared with conventional agents, such as UK.

Pleural disease

The incidence of pleural disease is increasing and the mortality and morbidity is high. Many recent RCTs have resulted in evidence-based guidelines published in 2023, pointing towards a more individualized and specialized management. Most patients with pleural disease are admitted at the A and E but can be managed in outpatient clinics. Thus, there is a need to establish specialized, multidisciplinary pleural clinics to ensure optimal, individualized and evidence-based management of the increasing number of patients with pleural disease in Denmark, as argued in this review.

Understanding the systemic effects of intrapleural tPA and DNase by evaluating effects on coagulation

Background

Complicated parapneumonic effusions and empyemas are common presentations that carry significant morbidity and mortality. Standard therapy includes antibiotics and chest tube placement. Due to the nature of the fluid, it is often difficult to drain completely using a chest tube. As outlined in multiple studies, intrapleural tissue plasminogen activator (tPA) and dornase alfa (DNase) are effective at helping clear these effusions and the avoidance of surgery. Despite research to better understand the effectiveness of the treatment and possible side effects, there continues to be a lack of data on potential systemic effects.

Methods

This prospective observational pilot study was conducted from May 2021 until June 2022. Basic demographics, complications, prothrombin time, activated partial thromboplastin time, D-Dimer, fibrinogen, and thromboelastography scans were measured both before and after infusion of chest tube tPA and DNase to assess for differences in coagulation using Signed Rank tests.

Results

A total of 17 patients were enrolled in the study. Two patients were excluded due to protocol deviations. The median change score for lysis of clot at 30 minutes (Ly30), our primary outcome of interest, was 0 (P=0.88). There were no significant changes in other coagulation measures when comparing pre and post treatment. One patient (5.9%) had intrapleural bleeding associated with therapy. Three patients (17.6%) underwent surgical intervention to further treat their complicated pleural effusion.

Conclusions

This is the first study to evaluate measurable changes in systemic coagulation after intrapleural tPA and DNase. Our data demonstrates no significant difference in coagulation after intrapleural tPA and DNase infusion, suggesting that there may not be clinically significant absorption.

Lemierre syndrome complicated by bronchopleural fistula

We present a 19-year-old woman, a case of Lemierre syndrome, who presented with fever, sore throat, and left shoulder pain. Imaging revealed a thrombus in the right internal jugular vein, multiple nodular shadows below both pleura with some cavitations, right lung necrotizing pneumonia, pyothorax, abscess in the infraspinatus muscle, and multiloculated fluid collections in the left hip joint. After inserting a chest tube and administering urokinase for the pyothorax, a bronchopleural fistula was suspected. The fistula was identified based on clinical symptoms and computed tomography scan findings. If a bronchopleural fistula is present, thoracic lavage should not be performed as it may cause complications such as contralateral pneumonia due to reflux.

Intrapleural Thrombolytics for Parapneumonic Effusion: A Network Metaanalysis

OBJECTIVES

Intrapleural thrombolytics have been trialed for facilitating pleural fluid drainage in patients with complicated parapneumonic effusion. The present study is a network metaanalysis of randomized clinical trials (RCTs) that have evaluated these thrombolytics.

METHODS

Electronic databases (Medline, Cochrane CENTRAL, and Google Scholar) were searched for appropriate RCTs evaluating the therapeutic effect of thrombolytics in patients with complicated parapneumonic effusion. Mortality, the proportion of patients referred for surgical intervention, and serious adverse events were the outcome measures. Random-effects model was used for generating direct and mixed treatment comparison pooled estimates. Grading of the evidence for key comparisons was carried out. Odds ratio with 95% confidence intervals was used to represent the pooled estimates.

RESULTS

Seventy-six studies were retrieved with the search strategy, of which 16 were included. No significant differences were observed in mortality. Compared to normal saline, significantly less proportion of patients was referred for surgical intervention with streptokinase (0.4, 0.2 to 0.8), urokinase (0.4, 0.2 to 0.8), alteplase (0.3, 0.1 to 0.7), and alteplase + DNase (0.2, 0.1 to 0.7). DNase alone increased the risk of referral to surgical intervention (3.4, 1.5 to 7.6). Only streptokinase was observed with an increased risk of serious adverse events compared to normal saline (2.8, 1.1 to 7.1) and alteplase (6.7, 1.1 to 39.9). Moderate quality of evidence was observed for streptokinase with normal saline for the proportion of patients referred for surgical intervention, while either low or very low quality strength was observed for all other comparisons.

CONCLUSION

Streptokinase, urokinase, alteplase, and alteplase + DNase were observed in patients referred for surgical interventions when used intrapleural in patients with parapneumonic effusion. Alteplase + DNase is likely to outperform others as it was observed with the least risk of patients referred for surgical interventions. Until additional data emerges that changes the pooled estimates, thrombolytics other than streptokinase are preferred due to the increased risk of serious adverse events.

A Retrospective Cohort Study Evaluating the Safety and Efficacy of Sequential versus Concurrent Intrapleural Instillation of Tissue Plasminogen Activator and DNase for Pleural Infection

Methods

We conducted a retrospective review of patients with pleural infection requiring intrapleural therapy at two tertiary referral centres.

Results

We included 84 (62.2%) and 51 (37.8%) patients who received sequential and concurrent intrapleural therapy, respectively. Patient demographics and clinical characteristics, including age, RAPID score, and percentage of pleural opacity on radiographs before intrapleural therapy, were similar in both groups. Treatment failure rates (defined by either in-hospital mortality, surgical intervention, or 30-day readmission for pleural infection) were 9.5% and 5.9% with sequential and concurrent intrapleural therapy, respectively (p = 0.534). This translates to a treatment success rate of 90.5% and 94.1% for sequential and concurrent intrapleural therapy, respectively. There was no significant difference in the decrease in percentage of pleural effusion size on chest radiographs (15.1% [IQR 6-35.7] versus 26.6% [IQR 9.9-38.7], p = 0.143) between sequential and concurrent therapy, respectively. There were also no significant differences in the rate of pleural bleeding (4.8% versus 9.8%, p = 0.298) and chest pain (13.1% versus 9.8%, p = 0.566) between sequential and concurrent therapy, respectively.

Conclusion

Our study adds to the growing literature on the safety and efficacy of concurrent intrapleural therapy in pleural infection.

Effectiveness of Immediate Video-Assisted Thoracoscopic Surgery for Empyema: A Multicentre, Retrospective Cohort Study

BACKGROUND

Because of limitations in previous randomised controlled trials and observational studies, the effectiveness of immediate video-assisted thoracoscopic surgery (VATS) for patients with empyema in real-world settings remains unclear.

OBJECTIVE

This study aimed to evaluate whether immediate VATS improves clinical outcomes in patients with empyema.

METHODS

This multicentre retrospective cohort study included 744 patients with physician-diagnosed empyema from six hospitals between 2006 and 2021. The exposure was VATS performed within 3 days of empyema diagnosis, the primary outcome was 30-day mortality, and secondary outcomes were 90-day mortality, length of hospital stay, and time from diagnosis to discharge. We used propensity score weighting to account for potential confounders. For outcome analyses, we used logistic regression for mortality outcomes and gamma regression for the number of days.

RESULTS

Among the 744 patients, 53 (7.1%) underwent VATS within 3 days, and 691 (92.9%) initially received conservative treatment. After propensity score weighting, the differences in 30- and 90-day mortalities between the immediate VATS and initial conservative treatment groups were 1.18% (95% confidence interval [CI], -10.7 to 13.0%) and -0.08% (95% CI, -10.3 to 10.2%), respectively. The differences in length of hospital stay and time from diagnosis to discharge were -3.22 (95% CI, -6.19 to -0.25 days) and -5.04 days (95% CI, -8.19 to -1.90 days), respectively.

CONCLUSIONS

Our real-world study showed that immediate VATS reduced the length of hospital stay and the time from diagnosis to discharge. Considering the small sample and differences in protocols between countries, further large-scale studies are warranted.

Two case reports of two interventional radiology techniques for the treatment of stage II empyema: Hydrodissection and guidewire-dissection

Empyema is an infection of the pleural space that is classified into 3 stages. Video-assisted thoracoscopic surgery is recommended as the first-line approach for stage II acute empyema. The purpose of video-assisted thoracoscopic surgery is also achieved with hydrodissection and guidewire-dissection by breaking the septa mechanically in the pleural cavity. Hydrodissection and guidewire-dissection are techniques in which a contrast medium is administered at high pressure and a guidewire is inserted into the pleural cavity to break the septa, respectively. Hydrodissection and guidewire-dissection might be minimally invasive alternatives for the treatment of septated empyema.

Association between intrapleural urokinase monotherapy and treatment failure in patients with pleural infection: a retrospective cohort study

BACKGROUND

Pleural infection, an infection of the pleural space, is frequently treated with antibiotics and thoracic tube drainage. In case of insufficient drainage, an intrapleural fibrinolytic agent is considered before surgical intervention. However, the effectiveness of fibrinolytic monotherapy is still controversial. Therefore, we aimed to examine the association between urokinase monotherapy and treatment failure in patients with pleural infection.

METHODS

In this retrospective observational study, patients with pleural infection underwent chest tube insertion were divided into two groups including patients treated with or without intrapleural instillation of urokinase. The propensity score overlap weighting was used to balance the baseline characteristics between the groups. Treatment failure was defined by the composite primary outcome of in-hospital death and referral for surgery.

RESULTS

Among the 94 patients, 67 and 27 patients were in the urokinase and non-urokinase groups, respectively. Urokinase monotherapy improved the composite outcome between the groups (19.4% vs. 48.1%, p = 0.01). After adjusting using propensity score overlap weighting, urokinase monotherapy improved the composite outcome compared to the non-urokinase group (19.0% vs. 59.5%, p = 0.003).

CONCLUSIONS

Urokinase monotherapy can be an important nonsurgical treatment option for patients with pleural infection.

TRIAL REGISTRATION

The participants were retrospectively registered.

Intrapleural Urokinase Injection after Medical Thoracoscopy for Empyema and Complicated Para-Pneumonic Effusion: A Case Series

Empyema and complicated para-pneumonic effusion (CPPE) often require surgical intervention because of insufficient antibiotic effect and chest tube drainage. From January 2017 to September 2021, we encountered seven patients who underwent intrapleural urokinase injection after medical thoracoscopy for the treatment of empyema or CPPE. None of the seven patients required further surgical interventions or showed any complications associated with the therapeutic procedures. The combined use of intrapleural urokinase injections and medical thoracoscopy may be an effective and safe therapeutic option for the management of empyema and CPPE.

Intrapleural Instillation of Sodium Bicarbonate versus Urokinase in Management of Complicated Pleural Effusion: A Comparative Cohort Study

Aim

The main target is evacuation; however, with evidence about the value of intrapleural instillation of different fibrinolytic agents still under evaluation, our aim was comparing the effectiveness and safety of intrapleural instillation of sodium bicarbonate (NaHCO₃) in comparison with urokinase in patients with infected pleural effusion.

Methods

Our prospective cohort study included 40 patients with complicated empyema; the diagnosis was based on analysis of aspirated fluid in association with radiological and bacteriological culture. The patients were subjected to instillation of two different fibrinolytic agents; the first one was NaHCO₃, the second was urokinase.

Results

The commonest underlying chest infection that was visualized by CT was pneumonia 70%. Nearly half of cases had community-acquired infection (45%), and more than half of them (55%) had anaerobic infection, and only five cases had TB pleural effusion based on ADA-positive, tuberculin skin test in addition to Abram's needles closed biopsy. The rate of repeated therapeutic thoracentesis success in each group was 85%; 80% in NaHCO₃ group, and 90% in urokinase group, both of them was significantly equal, P=0.37. Moreover, the frequency of complications in all patients was less than 13%, hence hemothorax and iatrogenic pneumothorax was 12.5%, and only 10% of cases were admitted in ICU after the maneuver, with insignificant difference in between the groups. However, looking at the smaller rate of RTT failure of NaHCO₃ or urokinase, the logistic regression model showed that RTT-NaHCO₃ was insignificantly related to failure in both unadjusted and adjusted models, P=0.37 and 0.32, respectively, and only smoking habits increase the likelihood of failure 9-fold (OR=8.9, P=0.04) with respect to age, sex, and treatment methods.

Conclusion

The efficacy of repeated therapeutic thoracentesis (RTT) with intrapleural instillation of NaHCO₃ was effective and safe, the same as urokinase, with consideration that NaHCO₃ was much more available and affordable than urokinase.

Incidence of complications from indwelling pleural catheter for pleural effusion: A meta-analysis

Indwelling pleural catheter (IPC) is widely used in patients with pleural effusion (PE). This meta-analysis aimed to comprehensively summarize the clinical complication from IPC. We searched four large electronic databases (PubMed, EMBASE, MEDLINE, and Cochrane Library) for potentially relevant studies and assessed the included studies' quality using the methodological index for nonrandomized studies' criteria. Extracted data were used to pool rates, and to conduct subgroup and meta-regression analyses. Forty-one studies involving a cumulative 4983 patients with 5650 IPCs were included in this meta-analysis. The overall incidence of IPC complications was 20.3% (95% confidence interval [CI]: 15.0-26.3). The top four complications were: overall infection incidence 5.7% (95% CI: 0.7-2.4); overall catheter abnormality incidence 4.4% (95% CI: 2.8-6.3); pain incidence 1.2% (95% CI: 0.4-2.4); and overall loculation incidence 0.9% (95% CI: 0.1-2.1). Subgroup and meta-regression analyses for overall complications and infections by country, PE site, and PE type demonstrated these factors did not contribute significantly to heterogeneity. Further subgroup analyses for infection of benign PE showed that the overall infection incidence (12.6% [95% CI: 8.1-17.8] vs 0.7% [95% CI: 0.0-4.5]) and empyema incidence (9.1% [95% CI: 5.3-13.8] vs 0.0% [95% CI: 0.0-2.3]) of patients with liver-related PE were significantly higher than that of patients with heart-related PE. Our meta-analysis showed reliable pooled incidences of IPC-related complications, with infection being the most common. These results serve to remind clinicians about the incidence of IPC-related complications and emphasize the importance of taking corresponding preventive and therapeutic steps.

Use of tunneled pleural catheters in chronic empyema: Two case reports and brief review of the literature

The incidence of empyema is increasing worldwide, which, coupled with the aging global population, makes the non-surgical management of pleural space infections increasingly important. Despite this, there remains no consensus for management of chronic empyema in those patients who are not surgical candidates and do not get adequate source control with chest tube and intra-pleural lytic therapy, particularly for patients with non-expandable lungs. We reviewed the literature regarding non-surgical management of chronic empyema and present two cases that support the use of pleuroscopy in conjunction with tunneled pleural catheters for management of chronic empyema in non-surgical candidates.

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.

Outcome of parapneumonic empyema managed surgically or by fibrinolysis: a multicenter study

Background

Parapneumonic empyema (PPE) management remains debated. Here we present the outcome of a comparable population with PPE treated over a 4-year period in two Thoracic Surgery University Centers with different approaches: one with an early “surgical” and the other with a “fibrinolytic” approach.

Methods

All operable patients with PPE managed in both centers between January 2014 and January 2018 were reviewed. Patients with persistent pleural effusion/loculations following drainage were managed by a “surgical” approach in one center and by “fibrinolytic” approach in the other. For each patient, we recorded the age, sex, hospital stay, morbidity/mortality and change in pleural opacity on chest X-ray before and at the end of the treatment.

Results

During the study period, 66 and 93 patients underwent PPE management in the “surgical” and “fibrinolytic” centers respectively. The population characteristics were comparable. Infection was controlled in all patients. In the “fibrinolytic” group, 20 patients (21.5%) underwent an additional drain placement while 12 patients (12.9%) required surgery to correct PPE. In the “surgical” group, 4 patients (6.1%) developed postoperative arrhythmia while 2 patients (3%) underwent a second surgery to evacuate a hemothorax. Median drainage {3 [2–4] vs. 5 [4–7] days} and hospital {7 [5–10] vs. 11 [7–19] days} durations were significantly lower in the “surgical” compared to the “fibrinolytic” center. Pleural opacity regression with therapy was significantly more important in the “surgical” compared to the “fibrinolytic” group (−22%±18% vs. −16%±17%, P=0.035).

Conclusions

Surgical management of PPE was associated with shorter chest tube and hospital duration and better pleural space control. Prospective randomized studies are mandatory.

Can intrapleural alteplase treatment be an alternative to videothoracoscopic deloculation and decortication in pleural empyema?

Introduction

Chest tube drainage is the first step in the management of complicated pleural effusions that have turned into empyema. In cases where adequate drainage cannot be provided or deloculation is required, intrapleural fibrinolytic therapy or surgical deloculation can be performed. Alteplase is a suitable agent for intrapleural fibrinolytic therapy. On the other hand, video-assisted surgery is an effective and minimally invasive treatment option for lung re-expansion.

Aim

The effect of intrapleural alteplase irrigation applied through the thoracic tube in the treatment of pleural empyema was investigated and whether it could be an alternative technique to video-assisted thoracoscopic surgery was evaluated.

Material and methods

The results of patients who were treated for empyema in our clinic were evaluated retrospectively. Twenty-one patients who underwent tube thoracostomy + intrapleural alteplase and 28 patients who underwent VATS deloculation were included in the study.

Results

The study included 35 male and 14 female patients. There were 21 patients in group 1, and 28 patients in group 2. The mean age was 50.6. The average length of thoracic tube stay was determined as 7.1 and 6.96 days. The duration of hospital stay in this group was 6.73 and 6.35 days. In 17 (81%) patients in group 1, the treatment was discontinued without the need for surgery.

Conclusions

VATS-D is an effective option in the treatment of pleural empyema. However, as seen in our study, intrapleural alteplase application is at least as effective as VATS-D in terms of treatment success.

Intrapleural Tenecteplase for Complicated Parapneumonic Pleural Effusion

Intrapleural thrombolytics have shown promising results in complicated parapneumonic pleural effusions reducing the need for surgical interventions. Until now, studies have evaluated primarily streptokinase, urokinase, and recently, alteplase. In this case series, we share our experience with tenecteplase-a tissue-specific plasminogen activator in 15 patients. We observed that tenecteplase is effective in 14/15 (93.3%) of our patients, and none of them had any bleeding episodes.

Actinomyces meyeri pleural empyema: A case report

We report the case of a man with intense cough for several months and a few days of severe dyspnea. A massive pleural empyema due to Actinomyces meyeri was diagnosed by radiological, microbiological and thoracoscopic means. Pleural infections caused by this anaerobic bacterium are very rare and should be considered when risk factors like male gender, chronic alcohol abuse, and poor oral hygiene are present. Penicillin-based antibiotic treatment and surgical decortication led to recovery.

Intrapleural use of urokinase and DNase in pleural infections managed with repeated thoracentesis: A comparative cohort study

Introduction

Evacuation of infected fluid in pleural infections is essential. To date, the use of an intrapleural fibrinolytic agent such as urokinase and DNase has not yet been assessed in infections managed by repeated therapeutic thoracentesis (RTT).

Methods

We performed a retrospective comparative study of two successive cohorts of consecutive patients with pleural infections from 2001 to 2018. Between 2001 and 2010, patients had RTT with intrapleural urokinase (RTT-U). After 2011, patients received intrapleural urokinase and DNase with RTT (RTT-UD). Data were collected through a standardized questionnaire.

Results

One hundred and thirty-three patients were included: 93 were men and the mean age was 59 years (standard deviation 17.2). Eighty-one patients were treated with a combination of intrapleural urokinase and DNase, and 52 were treated with intrapleural urokinase only. In the RTT-UD, RTT failure occurred in 14 patients (17%) compared to 10 (19%) in the RTT-U group (P = 0.82). There was no difference between the two groups in intensive care unit admission, surgical referrals or in-hospital mortality. RTT-UD was associated with faster time to apyrexia (aOR = 0.51, 95%CI [0.37–0.72]), a reduced length of hospital stay (aOR = 0.61, 95%CI [0.52–0.73]) and a higher volume of total pleural fluid retrieved (aOR = 1.38, 95%CI [1.02–1.88]). Complications were rare with only one hemothorax in the RTT-UD group and no pneumothorax requiring drainage in either group.

Conclusion

Compared to urokinase only, intrapleural use of urokinase and DNase in RTT was associated with quicker defervescence, shorter hospital stay and increased volumes of pleural fluid drained. Randomized controlled trials evaluating urokinase and DNase with RTT technique would be required to confirm these results.

Management of complex pleural disease in the critically ill patient

Disorders of the pleural space are quite common in the critically ill patient. They are generally associated with the underlying illness. It is sometimes difficult to assess for pleural space disorders in the ICU given the instability of some patients. Although the portable chest X-ray remains the primary modality of diagnosis for pleural disorders in the ICU. It can be nonspecific and may miss subtle findings. Ultrasound has become a useful tool to the bedside clinician to aid in diagnosis and management of pleural disease. The majority of pleural space disorders resolve as the patient’s illness improves. There remain a few pleural processes that need specific therapies. While uncomplicated parapneumonic effusions do not have their own treatments. Those that progress to become a complex infected pleural space can have its individual complexity in therapy. Chest tube drainage remains the cornerstone in therapy. The use of intrapleural fibrinolytics has decreased the need for surgical referral. A large hemothorax or pneumothorax in patients admitted to the ICU represent medical emergencies and require emergent action. In this review we focus on the management of commonly encountered complex pleural space disorders in critically ill patients such as complicated pleural space infections, hemothoraces and pneumothoraces.

Management of Pleural Infection

Pleural infection is a millennia-spanning condition that has proved challenging to treat over many years. Fourteen percent of cases of pneumonia are reported to present with a pleural effusion on chest X-ray (CXR), which rises to 44% on ultrasound but many will resolve with prompt antibiotic therapy. To guide treatment, parapneumonic effusions have been separated into distinct categories according to their biochemical, microbiological and radiological characteristics. There is wide variation in causative organisms according to geographical location and healthcare setting. Positive cultures are only obtained in 56% of cases; therefore, empirical antibiotics should provide Gram-positive, Gram-negative and anaerobic cover whilst providing adequate pleural penetrance. With the advent of next-generation sequencing techniques, yields are expected to improve. Complicated parapneumonic effusions and empyema necessitate prompt tube thoracostomy. It is reported that 16-27% treated in this way will fail on this therapy and require some form of escalation. The now seminal Multi-centre Intrapleural Sepsis Trials (MIST) demonstrated the use of combination fibrinolysin and DNase as more effective in the treatment of empyema compared to either agent alone or placebo, and success rates of 90% are reported with this technique. The focus is now on dose adjustments according to the patient's specific 'fibrinolytic potential', in order to deliver personalised therapy. Surgery has remained a cornerstone in the management of pleural infection and is certainly required in late-stage manifestations of the disease. However, its role in early-stage disease and optimal patient selection is being re-explored. A number of adjunct and exploratory therapies are also discussed in this review, including the use of local anaesthetic thoracoscopy, indwelling pleural catheters, intrapleural antibiotics, pleural irrigation and steroid therapy.

Precision targeting of the plasminogen activator inhibitor-1 mechanism increases efficacy of fibrinolytic therapy in empyema

Plasminogen activator inhibitor‐1 (PAI‐1) is an endogenous irreversible inhibitor of tissue‐type (tPA) and urokinase (uPA) plasminogen activators. PAI‐1‐targeted fibrinolytic therapy (PAI‐1‐TFT) is designed to decrease the therapeutic dose of tPA and uPA, attenuating the risk of bleeding and other complications. Docking site peptide (DSP) mimics the part of the PAI‐1 reactive center loop that interacts with plasminogen activators, thereby affecting the PAI‐1 mechanism. We used DSP for PAI‐1‐TFT in two rabbit models: chemically induced pleural injury and Streptococcus pneumoniae induced empyema. These models feature different levels of inflammation and PAI‐1 expression. PAI‐1‐TFT with DSP (2.0 mg/kg) converted ineffective doses of single chain (sc) tPA (72.5 µg/kg) and scuPA (62.5 µg/kg) into effective ones in chemically induced pleural injury. DSP (2.0 mg/kg) was ineffective in S. pneumoniae empyema, where the level of PAI‐1 is an order of magnitude higher. DSP dose escalation to 8.0 mg/kg resulted in effective PAI‐1‐TFT with 0.25 mg/kg sctPA (1/8th of the effective dose of sctPA alone) in empyema. There was no increase in the efficacy of scuPA. PAI‐1‐TFT with DSP increases the efficacy of fibrinolytic therapy up to 8‐fold in chemically induced (sctPA and scuPA) and infectious (sctPA) pleural injury in rabbits. PAI‐1 is a valid molecular target in our model of S. pneumoniae empyema in rabbits, which closely recapitulates key characteristics of empyema in humans. Low‐dose PAI‐1‐TFT is a novel interventional strategy that offers the potential to improve fibrinolytic therapy for empyema in clinical practice.

Medical thoracoscopy treatment for pleural infections: a systematic review and meta-analysis

Background

Complicated parapneumonic effusions and empyema represent advanced stages of pleural infections and are characterized by a high mortality. Medical thoracoscopy is a safe and minimally invasive endoscopic technique prescribed to treat severe pleural infections. However, only a few studies evaluated its success rate. A systematic review of observational studies was performed to assess the efficacy of medical thoracoscopy in patients with complicated parapneumonic effusions and empyema, as well as its predictive factors.

Methods

A search of the scientific evidence was carried out using PubMed, EMBASE, and Cochrane Central Register of Controlled Trials. Articles describing observational studies on medical thoracoscopy in patients with parapneumonic effusions and empyema were selected.

Results

Eight studies met the inclusion criteria. The pooled treatment success rate of thoracoscopy was 85% (95% CI 80.0–90.0%; I²: 61.8%) when used as first-line intervention or after failure of chest tube. The pooled complication rate was 9.0% (95% CI 6.0–14.0%; I²: 58.8%). A pooled difference of treatment success of 9.0% (95% CI 1.0–18.0%) was found when post-thoracoscopy intra-pleural fibrinolysis was prescribed. Pooled success rate was higher in cases with pleural fluid culture negativity (pooled difference: 14.0%; 95% CI 4.0–24.0%).

Conclusions

Medical thoracoscopy is effective and safe when prescribed for complicated parapneumonic effusions and empyema. Bacteriological negativity of pleural effusion specimens and administration of adjuvant intra-pleural fibrinolysis after the procedure are associated with a higher success rate.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01492-9.

[Successful treatment of a stage III pleural empyema following a COVID-19 infection]

Der parapneumonische Pleuraerguss ist eine häufige Komplikation nach einer Pneumonie und kann zur Entwicklung eines Pleuraempyems führen. Das Pleuraempyem ist eine lebensbedrohliche Infektion, die mit Antibiotika, interventioneller Drainage oder in späteren Stadien operativ versorgt werden kann. Hier beschreiben wir den ersten Fall eines Pleuraempyems nach vorangegangener COVID-19-Infektion ohne respiratorische Insuffizienz bei einem zuvor gesunden, sportlichen Patienten. Der Patient wurde initial mit Antibiotika und interventioneller Drainage versorgt, musste aber aufgrund einer klinischen Verschlechterung erneut stationär aufgenommen werden. Operativ zeigte sich ein Pleuraempyem 3. Grades, das thorakoskopisch erfolgreich mittels Dekortikation versorgt werden konnte. Die präoperative SARS-CoV-2-Testung war negativ. Der Patient hat sich komplett erholt und konnte entlassen werden.