Surgical interventions for pleural infection

Abstract

Pleural infection (PI) remains a serious clinical condition associated with high morbidity, prolonged hospitalisation and significant mortality, despite advances in medical therapy. Characterised by infection and inflammation within the pleural cavity, PI is increasingly complicated by antimicrobial resistance. While antibiotics and drainage constitute first-line treatment, surgical intervention becomes essential in advanced or refractory cases. Video-assisted thoracoscopic surgery (VATS) has emerged as the preferred minimally invasive approach in early-stage disease, offering advantages such as reduced post-operative pain, shorter hospital stays and faster recovery. In more complex stages, open decortication or thoracotomy may still be required. This narrative review explores the full spectrum of surgical strategies – including VATS, open decortication, open window thoracostomy, vacuum-assisted closure therapy and the innovative FlexVATS technique – highlighting their indications, timing and evolving roles in contemporary practice. We also underscore the importance of post-operative care, emphasising respiratory rehabilitation, pain management, nutritional support and infection surveillance. Prognostic tools, particularly the RAPID score, are discussed for their potential to guide early risk stratification and optimise timing of surgical intervention. Given the complex nature of PI, a multidisciplinary approach involving thoracic surgeons, pulmonologists, infectious disease specialists, physiotherapists and nutritionists is essential. A patient-centred, multimodal treatment strategy tailored to disease stage and individual risk factors remains the cornerstone of successful recovery. Continued research into long-term outcomes and advanced diagnostics is critical to improving care in this challenging clinical domain.

Shareable abstract

This review discusses surgical management of pleural infection, highlighting optimal timing, key indications, and the strengths and limitations of current techniques to support tailored, evidence-based clinical strategy. https://bit.ly/4lo1vVg

Educational aims

• To evaluate how to select the most appropriate and individualised therapeutic strategy – surgical or non-surgical – for patients with pleural infection, based on clinical presentation and radiological findings.

• To define optimal surgical timing and compare available surgical approaches for pleural infection, including video-assisted thoracoscopic surgery (VATS) and open thoracotomy, highlighting their respective indications, advantages and limitations.

• To explore the utility of prognostic tools in predicting mortality and guiding early surgical decision-making and to emphasise the importance of a multidisciplinary, patient-centred approach to pleural infection management, integrating surgical, medical, respiratory, infectious disease and nutritional expertise.

Introduction

Pleural infection (PI) remains a common and clinically-significant condition that has evolved from early open drainage with high mortality to improved outcomes through modern chest tube insertion and advanced surgical strategies [1]. Despite better antimicrobial therapy, imaging and disease understanding, PI remains challenging and is associated with notable morbidity and mortality.

PI includes bacterial invasion of the pleural space, ranging from parapneumonic effusions to complicated empyema [2]. Pleural empyema (PE) involves thick, purulent pleural fluid with high protein and leukocyte levels. It can be primary (often iatrogenic) or secondary (associated with pneumonia). Invasive procedures like computed tomography (CT)-guided biopsy, thoracentesis or pleurodesis can lead to infection, as can trauma [3].

Post-operative PE, especially after lung resection, may be complicated by bronchopleural fistulas, increasing morbidity and mortality [4]. Empyema necessitans, the extension of pus into the chest wall and subcutaneous tissues, is commonly caused by tuberculosis and affects immunocompromised individuals [5].

PI incidence peaks in children and the elderly [6]. Though 20–40% of pneumonias cause pleural effusions, only 5–7% progress to empyema. Nonetheless, PE incidence is rising, particularly in Europe and other Western countries, with more patients needing surgery [7]. Risk factors include diabetes, thoracic malignancies, chronic lung disease, immunosuppression, neurological disorders, alcoholism and drug use [8].

PE typically progresses through distinct pathological stages, and accurate staging is critical for selecting the most appropriate therapeutic approach. According to the American Thoracic Society, PE evolves through three stages: exudative, fibrinopurulent and organising [9], as summarised in table 1.

TABLE 1.

American Thoracic Society staging system for pleural empyema

Stage	Name	Characteristics	Pleural fluid findings	Management
Stage I	Exudative phase	Sterile, clear fluid; early neutrophilic response	Normal pH and glucose	Antibiotics ± simple thoracic drainage
Stage II	Fibrinopurulent phase	Turbid or purulent fluid; fibrin deposition, septations and loculations present	pH <7.2, Glucose <40 mg·dL−1	Aggressive drainage ± surgical intervention
Stage III	Organising phase	Fibroblast proliferation; thick pleural peel; possible trapped lung	Thickened pleura; fluid often non-drainable	Surgical decortication often required

In this narrative review, we aim to provide an updated overview of PI, with a particular focus on current surgical management strategies and potential future directions in surgical treatment.

Methods

We conducted a literature search using PubMed, Scopus and Web of Science for articles published between 2000 and 2024 using combinations of keywords such as “pleural infection”, “pleural empyema”, “surgical treatment”, “VATS”, “decortication” and “outcomes”. We included original studies, reviews, and guidelines from international societies focusing on adult patients. Exclusion criteria included non-English publications, studies on paediatric populations and case reports without broader clinical relevance.

This method enabled a comprehensive overview of surgical indications, techniques, post-operative care and prognostic scoring.

Diagnosis of pleural infection

PI diagnosis remains challenging due to its non-specific and variable clinical presentation. While fever and pleuritic pain are typical, some patients show only systemic signs such as malaise or weight loss, mimicking malignancy [10].

Imaging plays a pivotal role in the diagnostic pathway. Although chest radiography is typically the first-line modality, it has limited sensitivity and may fail to detect early or loculated effusions (figure 1a) [11]. Bedside thoracic ultrasound is more effective in characterising pleural fluid, including assessment of echogenicity, septations and loculations (figure 1b) [12]. Contrast-enhanced CT remains the gold standard for evaluating suspected PE, providing detailed insights into pleural morphology such as thickening, enhancement and the characteristic “split pleura sign,” which is strongly associated with disease progression (figure 1c–d) [13]. CT also facilitates identification of underlying parenchymal abnormalities and supports procedural planning.

FIGURE 1.

a) Posteroanterior chest radiograph showing an encapsulated right pleural empyema. b) Right thoracic cavity ultrasound scan showing an echogenic pleural effusion with multiple septations/loculations, associated with underlying lung consolidation. c) Axial chest computed tomography (CT) scan showing a right pleural collection with thickened surrounding pleura and multiple gas bubbles. d) Coronal chest CT scan showing a multiloculated left pleural collection with small intrapleural air bubbles and associated lung atelectasis.

Thoracentesis is a critical diagnostic intervention when imaging reveals a significant or loculated effusion in a symptomatic patient. It is indicated for all suspected parapneumonic effusions (PPEs) when the pleural fluid thickness exceeds 1 cm on chest radiography or 2 cm on CT [14]. The procedure should be performed under ultrasound guidance to minimise complications. In addition to confirming infection, pleural fluid analysis – particularly when pH <7.2 or glucose <40 mg·dL⁻¹ – helps distinguish complicated PPE from PE and informs further management [15]. Although microbiological cultures frequently yield negative results, they remain essential for guiding antimicrobial therapy and differentiating community from hospital-acquired pathogens [2].

Management of pleural infection

Pharmacological therapy

The treatment of complicated PI centres on addressing the underlying cause and ensuring adequate removal of infected pleural fluid when indicated.

Antibiotics represent the cornerstone of management at all stages of PI [16, 17]. Empirical therapy should be initiated based on local microbiological data and the clinical context, and subsequently refined once culture results are available (typically positive in ∼60% of cases) [17]. The British Thoracic Society (BTS) and the American Association for Thoracic Surgery (AATS) advocate for the use of broad-spectrum antibiotics effective against Gram-positive, Gram-negative, and anaerobic organisms. Recommended regimens include β-lactam/β-lactamase inhibitor combinations, third-generation cephalosporins, and carbapenems [16, 18].

For community-acquired infections, a parenteral second- or third-generation cephalosporin (e.g., ceftriaxone) combined with metronidazole or an aminopenicillin/β-lactamase inhibitor (e.g., sulbactam) is advised. In contrast, treatment for hospital-acquired or postprocedural empyema should include agents targeting methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa (e.g., vancomycin, cefepime, and metronidazole, or vancomycin with piperacillin/tazobactam). Anaerobic bacteria are frequently implicated in empyema, particularly in association with lung abscesses, necrotising pneumonia, and bronchopleural fistulas [19]. Continued anaerobic coverage is recommended even when anaerobes are not isolated, given their known involvement and the difficulty in culturing them from pleural specimens. Empiric coverage for atypical organisms is generally not indicated [20].

To explore adjunctive strategies for preventing disease progression, Fitzgerald et al. [21] conducted the STOPPE (Steroid Therapy and Outcome of Parapneumonic Pleural Effusions) trial, the first randomised trial investigating corticosteroids in adults with PPE. While the study found no significant harm from corticosteroid use, additional research is needed, particularly in specific subpopulations and with higher doses of dexamethasone.

Invasive medical management

The removal of infected fluid is the next step in management when antibiotic therapy alone proves insufficient. In stage I empyema (the exudative phase), where the pleural effusion is typically sterile, non-loculated and characterised by early pleural thickening; management consists of thoracic drainage combined with initially empirical, followed by targeted, antibiotic therapy [22].

The latest BTS Guideline for Pleural Disease advocates an algorithmic approach to invasive PI management. Immediate chest tube insertion is recommended if frank pus is observed during thoracentesis. If pus is not present, pleural fluid pH should be measured. Drainage is indicated when the pH is <7.20 or when the pH is 7.2–7.4 in conjunction with lactate dehydrogenase >900 IU·L⁻¹ or pleural glucose <40 mg·dL⁻¹ [23].

Large-bore chest tubes have traditionally been preferred over small-bore catheters due to their perceived superiority in draining high-viscosity pleural fluid and a reduced risk of obstruction. However, recent studies have demonstrated that small-bore chest tubes are not inferior in terms of clinical efficacy [24]. The 2023 BTS guidelines support their use, highlighting advantages such as reduced pain and easier insertion, without compromising therapeutic outcomes [23]. Nonetheless, many of these studies are non-randomised, and patients with more complex pleural effusions were more often treated with larger-bore drains, introducing potential selection bias.

The optimal timing for chest tube removal is determined by the patient's clinical progress and the nature and volume of drained fluid. Once the effusion becomes clear yellow and daily drainage volume decreases to 200–500 mL, chest tube removal is typically appropriate [25].

A recent study has suggested that repeated thoracentesis may be a viable alternative to chest tube placement for small, uncomplicated effusions (<450 mL) [26]. However, the AATS guidelines do not support thoracentesis alone in cases of infected collections [18].

The Pleural Infection Longitudinal Outcome (PILOT) study, the largest international multicentre prospective observational trial (2020), reported a failure rate of 33.5% for standard medical therapy comprising antibiotics and chest tube drainage [27].

To avoid surgery, several non-surgical adjuncts are increasingly employed, including:

• Intrapleural instillation of fibrinolytic/enzymatic therapy (IPET);

• Saline irrigation;

• Intrapleural antibiotic administration via chest drain.

Fibrinolytic therapy via pleural catheters facilitates loculation breakdown, reduces viscosity and promotes drainage. Combination regimens using tissue plasminogen activator (tPA) and deoxyribonuclease (DNase) have garnered particular interest [28]. Although no consensus exists on the optimal agent, streptokinase, urokinase and tPA are all in use.

The first Multicentre Intrapleural Sepsis Trial (MIST1, 2005) showed no benefit of streptokinase [29], whereas MIST2 (2011) demonstrated that combined tPA/DNase significantly reduced surgical referrals and hospital length of stay (LOS) [30]. The more recent MIST3 trial (2023) further validated early IPET, reporting comparable outcomes to surgery in terms of LOS, with improved quality of life and reduced pain [31]. Comparative studies indicate that tPA/DNase and urokinase offer similar efficacy, though tPA/DNase may be more cost-effective despite a slightly higher risk of bleeding [32]. Selected series report success rates exceeding 90% for IPET, making it a safe and effective option for patients unsuitable for surgery [28, 30]. Although the 2017 AATS guidelines do not formally endorse IPET [18], a more recent consensus statement supports its use as a first-line or rescue therapy when conventional drainage fails [33]. The principal concern with IPET remains bleeding. However, a large retrospective multicentre study of 1850 patients reported a low complication rate of 4.2%, with no major adverse events [34].

Saline irrigation may serve as a straightforward and cost-effective alternative to fibrinolytics. Though no randomised controlled trials have evaluated this approach, it may be considered when IPET is contraindicated or bleeding risk is elevated [35].

Finally, the European Respiratory Society and the European Society of Thoracic Surgeons (ESTS) have explored the use of intrapleural antibiotics as an emerging treatment modality, particularly in post-lung resection infections [36]. The rationale is that direct instillation could achieve higher local drug concentrations with fewer systemic effects. However, the AATS guidelines note a lack of evidence supporting improved microbiological or clinical outcomes from this approach, and therefore do not recommend its routine use [18].

Few studies in the literature have directly compared the outcomes of conservative treatments versus surgery for PI. Among recent contributions, Federici et al. [37] conducted a comparative analysis between IPET and VATS in two matched patient cohorts treated at different centres. While infection control and overall outcomes were comparable between the groups, the IPET cohort experienced significantly longer drainage durations and hospital stays. Additionally, some patients required multiple drainage procedures, and up to 12% ultimately needed surgical intervention for definitive management. These findings suggest that although IPET may be effective in selected cases, surgery provides superior pleural space control, albeit with an inherent risk of surgical complications.

Surgical management of pleural infection

Current guidelines recommend initiating surgical consultation within 24–48 h after chest tube insertion in patients who do not demonstrate clinical or radiological improvement, in order to prevent delays in definitive management. Surgical intervention is generally considered when medical therapy fails, typically after 5–7 days of appropriate antibiotic treatment and drainage, or in cases of organised empyema characterised by extensive pleural fibrosis [17, 18, 23].

The primary objectives of surgical intervention are to: 1) control the infectious source, 2) evacuate purulent material and necrotic debris, and 3) re-expand the lung and restore normal chest wall mechanics [38].

Stage II empyema often necessitates surgical debridement and, when indicated, decortication. VATS is the preferred first-line surgical approach in these patients [39]. However, in clinical settings, patients frequently present with overlapping features of stage II and stage III disease.

In stage III empyema, chronicity leads to dense fibrous adhesions, rind formation, and lung entrapment. At this stage, drainage is no longer effective and thoracotomy with open decortication becomes necessary [38]. In recent years, VATS has been trialled in selected stage III cases [40], reflecting the growing feasibility of minimally invasive approaches in complex empyema.

The BTS supports the American Thoracic Society classification: in stage I (exudative), chest drainage and antibiotics are sufficient, whereas surgery is warranted in stage II (fibrinopurulent) and stage III (organising) disease (figure 2) [9, 16].

FIGURE 2.

Management of pleural empyema according to the American Thoracic Society stages. VATS: video-assisted thoracoscopic surgery.

A nationwide epidemiological study found that 64.9% of patients managed with chest tube drainage did not require additional intervention. Nevertheless, approximately 33% of patients fail initial conservative management and ultimately require surgery [41]. Across studies, the surgical intervention rate for PE ranges from 36% to 65% [33]. Two small randomised controlled trials comparing chest tube drainage with primary surgery demonstrated reduced LOS in patients undergoing initial surgical intervention [42]. Despite limitations such as non-standardised treatment criteria, additional studies suggest that delays in surgical referral are associated with conversion from VATS to open surgery [43]. Delayed intervention in stage II–III empyema also correlates with increased perioperative risk and poorer outcomes.

VATS pleural debridement

VATS pleural debridement is indicated for early-stage infections, particularly in fibrinopurulent empyema when medical therapy and drainage are ineffective (figure 3a–c). In the early organising phase, VATS serves as a definitive option, providing advantages such as reduced post-operative pain, shorter LOS and faster recovery relative to open thoracotomy [44]. It is preferred in low-risk surgical candidates, whereas fibrinolysis remains a valuable alternative for patients deemed unfit for surgery.

FIGURE 3.

Surgical techniques. a) Video-assisted thoracoscopic surgery (VATS) debridement: intraoperative view of a septated and multiloculated pleural empyema. b) VATS debridement: lysis and suction of pleural pseudomembranes, fibrinous deposits and necrotic tissue. c) VATS debridement: purulent material draining from loculated collections and pleural peel. d) Pleural decortication performed via posterolateral thoracotomy.

Surgical technique

The standard VATS procedure typically employs three ports arranged in a triangular configuration for optimal access. Depending on surgeon preference, biportal or uniportal techniques may also be utilised.

A double-lumen endotracheal tube is used to facilitate single-lung ventilation. The patient is placed in the lateral decubitus position with the ipsilateral arm elevated, and the table is flexed at the level of the scapular tip for enhanced exposure. The camera port is generally positioned in the 7th or 8th intercostal space along the midaxillary line, with two additional working ports placed anteriorly and posteriorly under direct visualisation. The procedure is performed using a 10 mm, 30° thoracoscope. Following lung collapse, the pleural cavity is examined for fibrin, loculations and pleural peel. Purulent material is aspirated and submitted for microbiological and cytological analysis. Debridement involves meticulous removal of fibrinous and necrotic tissue using suction, graspers, and blunt dissection. Pseudomembranes are also sampled. Loculations are disrupted, and in cases of trapped lung, partial decortication is performed by carefully peeling the visceral pleura to restore lung expansion. Additionally, division of the inferior pulmonary ligament may be performed to facilitate optimal lung re-expansion. Throughout the procedure, care is taken to minimise injury to lung parenchyma and control bleeding. The pleural space is thoroughly irrigated with warm saline to reduce infectious burden. Two chest tubes (28–32 Fr) are then placed – apically and basally – and connected to continuous suction for post-operative drainage.

New perspectives in VATS

Management of stage II empyema is undergoing continuous evolution due to advances in surgical and anaesthetic techniques. The increasing use of uniportal VATS and non-intubated thoracic surgery is reshaping the approach to empyema [45]. Parallel developments in anaesthesia include growing interest in awake VATS, conducted under regional anaesthesia and spontaneous ventilation [46]. These techniques minimise airway manipulation and are associated with faster recovery and fewer complications in selected high-risk patients.

Despite these innovations, standardised criteria for choosing surgical and anaesthetic strategies in PE remain lacking. Decision-making is largely individualised, relying on institutional expertise, team experience and patient-specific factors. Consequently, the most effective approach often involves tailoring interventions to local capabilities and clinical context.

Pleural decortication

Stage III empyema (the organising phase) is marked by the formation of a thick fibrous peel encasing the lung, which impairs expansion and compromises respiratory function [9]. At this advanced stage, surgical intervention becomes imperative. Open decortication via thoracotomy is frequently the most effective approach, particularly when minimally invasive strategies are insufficient (figure 3d). This procedure is typically reserved for patients who have not responded to less invasive treatments or who present with advanced infection, persistent sepsis, and compromised pulmonary function [47]. Although more invasive, thoracotomy remains a definitive and effective strategy in selected cases. Several studies and clinical reports support its efficacy in improving lung function and resolving infection when performed at the appropriate stage.

Surgical technique

Open pleural decortication begins with the patient positioned in the lateral decubitus orientation to optimise surgical exposure. The operating table is flexed at the scapular tip to widen the intercostal spaces.

A posterolateral thoracotomy is commonly performed, typically through the 5th intercostal space, as it offers excellent exposure of the hemithorax, pleural cavity and hilar structures. However, the choice of surgical access may vary depending on the disease location, as well as the preference and institutional experience of the surgeon. Upon entering the pleural cavity, a thorough inspection is undertaken.

In chronic empyema, the space is often obliterated by a dense fibrous peel encompassing the lung, diaphragm, mediastinum and chest wall. The surgeon evacuates residual purulence and lyses adhesions to re-establish anatomical pleural planes. Decortication proceeds with the elevation of the parietal pleura from the chest wall, followed by careful dissection of the visceral pleura [47]. Visceral decortication is technically the most delicate step. The fibrotic cortex is dissected from the lung surface using both sharp and blunt techniques. The goal is to remove the constricting peel without damaging the underlying lung parenchyma, thereby enabling full re-expansion. Meticulous haemostasis is essential due to the vascularity of fibrotic tissues and the risk of bleeding from both pleural surfaces.

Following decortication, the pleural space is irrigated with warm saline to remove debris. Lung re-expansion is assessed under direct vision to identify any air leaks. Typically, one chest tube is placed apically and another basally (28–32 Fr) to ensure effective post-operative drainage.

VATS versus open decortication

The choice between VATS and open thoracotomy for pleural decortication remains dependent on clinical judgment and surgeon experience [48]. VATS has gained popularity as a minimally invasive option in early-stage empyema, particularly the fibrinopurulent phase (stage II). However, its role in advanced-stage disease (stage III) is more controversial. The presence of a dense, fibrous rind, extensive adhesions, or lung entrapment may limit the efficacy of thoracoscopic techniques and preclude complete decortication.

In such complex scenarios, open thoracotomy remains the gold standard, offering superior exposure, tactile feedback and the ability to perform more radical resection. This approach also allows for optimal control of bleeding and management of bronchopleural fistulas, ensuring both haemostasis and aerostasis, critical for successful surgical outcomes.

That said, the decision to pursue VATS or open surgery must be individualised. In experienced hands, VATS may be feasible and effective even in select stage III cases, provided that key objectives (complete debridement, full lung re-expansion, and secure haemostasis/aerostasis) can be achieved [49]. Ultimately, the chosen surgical approach should prioritise both the safety and effectiveness of the intervention, tailored to the specific clinical circumstances to ensure the best possible outcome.

Open window thoracostomy

Open window thoracostomy (OWT) is a highly specialised surgical technique involving the creation of a permanent or semi-permanent opening in the chest wall to facilitate continuous drainage and aeration of the pleural cavity (figure 4). It is primarily indicated for refractory PI, chronic empyema, or cases complicated by bronchopleural fistulas, particularly when other treatment modalities have failed [50].

FIGURE 4.

Open window thoracostomy (OWT). a) Early-stage OWT showing fibrinopurulent material at the cavity bed. b) Chronic OWT with a clean cavity bed and evident granulation tissue.

Originally developed for managing tuberculosis-related empyema, the indications for OWT have broadened to include parapneumonic and post-surgical empyema [50]. More recently, OWT has also been utilised in patients experiencing severe infectious complications following oncologic lung resections, especially those progressing to septic shock [51]. This approach helps prevent fluid reaccumulation and limits anaerobic bacterial proliferation by improving cavity oxygenation.

Despite the emergence of newer alternatives, OWT remains a valuable component of the surgical armamentarium, especially in critically ill patients requiring rapid decontamination of the pleural space. Its implementation, however, poses notable challenges due to the complex medical and surgical needs of this population [52]. Patients undergoing OWT often have prolonged LOS, recurrent infections and multiple comorbidities, which can complicate management.

Surgical technique

Under general anaesthesia, a large incision is made in the lateral or posterolateral thoracic wall, typically between the ribs and involving the resection of two to three ribs, to create a window for direct access to the empyema cavity. After opening the chest wall, infected material, pus and necrotic tissue are debrided and sampled for microbiological analysis. The wound is left partially open to permit ongoing drainage. The fibrotic empyema wall is resected in accordance with the window dimensions, and the skin is loosely sutured to the edges of the cavity to maintain patency. The cavity is packed with dressings or sponges, which are changed regularly. This configuration allows for continuous evacuation of purulent contents, promoting cavity contraction and infection control.

Once the infection is resolved and the pleural cavity has stabilised, closure of the window is planned to restore chest wall integrity and reduce future infection risk. This reconstructive phase may require complex interventions such as muscle flaps, skin grafting, or synthetic materials, depending on the defect size and the patient's overall condition [52]. Careful surgical planning is essential to achieve durable structural support and satisfactory aesthetic and functional outcomes.

Vacuum-assisted closure therapy

Vacuum-assisted closure (VAC) therapy has become an important adjunct in the management of complex thoracic infections, particularly in patients with persistent empyema cavities, infected thoracostomy sites or post-OWT wounds. Initially developed for soft tissue infection management, VAC therapy has been successfully adapted for thoracic applications [53].

VAC therapy applies continuous or intermittent negative pressure to the pleural cavity or wound bed through a specialised foam dressing connected to a suction device. This technique facilitates the evacuation of residual fluid, reduces local oedema, promotes granulation tissue formation and can accelerate wound healing. Its utility is especially evident in frail or high-risk patients who are unsuitable for major surgical reinterventions, or those with prolonged air leaks, necrotising infections, or bronchopleural fistulas [53]. In selected cases, VAC therapy may serve as a bridge to definitive closure, such as muscle flap reconstruction.

Although high-quality randomised trial data are limited, numerous case series and observational studies support the efficacy and safety of VAC therapy in thoracic infections. These findings underscore its growing role in the multimodal management of advanced or recurrent empyema.

FlexVATS

The increasing focus on reducing surgical trauma and enhancing recovery has led to the development of innovative, less invasive techniques in PE management. One such advancement is flexible video-assisted thoracoscopic surgery (FlexVATS), as introduced by Stüben et al. [54], which combines flexible endoscopy with negative pressure therapy using sponge material and open-pore film.

Unlike conventional VATS, which employs rigid scopes, FlexVATS utilises a flexible endoscope, typically a standard 8–10 mm gastroscope, enabling access to anatomically narrow or tortuous regions of the empyema cavity. However, FlexVATS is limited to local debridement and does not allow for formal decortication. During the procedure, the flexible endoscope is inserted via the chest drainage channel and used to bluntly disrupt septations within the empyema cavity. A sponge segment is then inserted, and an endovac system applies negative pressure to facilitate drainage and granulation. Dressings are changed every 3–8 days depending on clinical progress. As granulation improves, sponge size is progressively reduced until a clean wound bed and restored lung compliance are achieved.

Initial results are promising: approximately 70% of patients were successfully managed with FlexVATS without significant air leaks or haemorrhage. Compared to traditional thoracotomy or VATS, FlexVATS was associated with shorter LOS and showed a trend toward lower 90-day mortality [54]. This technique may represent a viable option for critically ill patients ineligible for conventional surgery, as it can be performed without single-lung ventilation.

Surgical emergencies for uncommon pleural infection

PI secondary to mediastinitis or oesophageal perforation constitutes a true surgical emergency. These conditions often present with rapidly progressing sepsis, mediastinal involvement and multi-compartmental contamination of the pleural space, necessitating urgent drainage, debridement, and definitive repair of the underlying pathology.

Oesophageal rupture may result from trauma, foreign body ingestion, caustic injury, malignancy, or may occur spontaneously. The latter, known as Boerhaave's syndrome, is a life-threatening event caused by sudden increases in intra-oesophageal pressure, typically following forceful vomiting. Delayed diagnosis, often due to vague or nonspecific symptoms, necessitates surgical management [55]. In unclear cases, oesophagography is recommended; evidence of contrast extravasation confirms diagnosis. Although few case reports describe concurrent management of oesophageal perforation with empyema and mediastinitis, the optimal approach remains debated, especially in late presentations. While conservative treatment (e.g., nasogastric decompression, parenteral nutrition, antibiotics and chest drainage) is sometimes considered, surgical repair is generally associated with superior outcomes (8% mortality with surgery versus 50% with conservative management) [55].

Mediastinitis, often descending from head and neck infections or related to oesophageal or sternal sources, carries a high mortality rate of up to 40%, increasing to 64% in septic patients [56]. Negative intrathoracic pressure during respiration facilitates infection spread from the neck into the mediastinum and pleural space.

Early recognition, aggressive antibiotic therapy and prompt surgical intervention remain essential. The gold standard for mediastinal and pleural decontamination is a posterolateral thoracotomy combined with a cervical approach. However, VATS has also been successfully utilised in older or frail patients and is increasingly gaining traction as a safe and effective alternative to open surgery, particularly due to its reduced perioperative morbidity and improved recovery profile [56].

Post-operative management of pleural infection

Post-operative care following surgical intervention for PI is inherently complex, reflecting both the severity of the underlying disease and the vulnerability of the affected patient population. Chronic infection often induces prolonged systemic inflammation and nutritional compromise, contributing to a generalised state of physiological fragility.

Close clinical monitoring is vital to ensure effective lung re-expansion and to detect potential complications. Serial chest radiographs are employed to evaluate lung recovery and verify adequate pleural drainage. Post-operative antibiotic therapy is maintained and adjusted according to microbiological culture and sensitivity results. The optimal duration of therapy varies depending on clinical response, comorbidities, adequacy of source control and the patient's overall condition. In general, treatment ranges from 2–6 weeks. Guidelines recommend a minimum of 2 weeks from the time of drainage and clinical improvement (AATS), or at least 3 weeks (BTS) [18, 23].

Respiratory rehabilitation is a cornerstone of post-operative care, especially in patients with chronic empyema or fibrothorax [57]. Early implementation of chest physiotherapy and incentive spirometry promotes lung re-expansion, restores ventilation–perfusion balance and prevents post-operative complications.

Chest drains are maintained until fluid output decreases substantially and imaging confirms full lung re-expansion. Removal is guided by clinical and radiological assessments.

Pain control following thoracotomy is critical, as inadequate analgesia can compromise ventilation and effective coughing, increasing the risk of complications such as atelectasis, secretion retention and pneumonia. Multimodal analgesia and early mobilisation are essential for optimising recovery and reducing morbidity [58].

Nutritional support and close monitoring for infection are also fundamental, particularly in patients with prolonged hospital stays or ongoing sepsis [57].

Ultimately, the post-operative management of PI requires a multidisciplinary approach involving thoracic surgeons, pulmonologists, infectious disease specialists, physiotherapists and nutritionists. Comprehensive perioperative care can markedly enhance functional recovery and quality of life in this high-risk patient population.

Post-operative complications of pleural infection surgery

Surgical intervention for PI can be associated with several notable post-operative complications. Among the most frequent is prolonged air leak (PAL), reported in up to 7.5% of cases following decortication, particularly in patients with underlying COPD, and often necessitating reoperation [58]. PAL can lead to subcutaneous emphysema, delayed recovery and impaired lung re-expansion. In patients with COPD, reoperation rates due to PAL may reach as high as 30%, especially when conservative management fails. Closely related to PAL is incomplete lung re-expansion, which may result from dense pleural adhesions, parenchymal stiffness, or trapped lung physiology. Poor lung re-expansion contributes to persistent pleural space, increasing the risk of recurrent infection or empyema and may necessitate additional procedures such as muscle flap reconstruction or OWT [51, 52, 59].

Post-operative bleeding, including haemothorax or intrapleural haemorrhage, is another serious complication. Iatrogenic injury to intercostal or pleural vessels during decortication or chest tube insertion can result in significant blood loss, haemodynamic instability, and the need for urgent re-intervention or transfusion [43]. In some series, reoperation due to post-operative haemorrhage has been reported in up to 2–4% of cases.

PI recurrence is also a concern. A recent retrospective study of 1000 patients reported recurrence in approximately 4% of cases, with a median recurrence interval of 37.5 days [59]. Recurrence negatively affected patient outcomes and increased healthcare resource utilisation. Identified risk factors included diabetes mellitus, low pleural fluid glucose, Streptococcus species infection, and delays in surgical intervention.

Careful preoperative risk stratification, particularly in patients with COPD or nutritional deficiencies, alongside meticulous surgical technique, remains crucial to minimise complications [27]. Equally important is early post-operative surveillance and timely management of adverse events to optimise patient outcomes and reduce the likelihood of reoperation.

Prognostic outcomes and RAPID score

The overall healthcare burden associated with PI is considerable. Around 25% of patients require hospitalisation for over 30 days, with median stays of 12–15 days among those undergoing surgery, and even longer durations in conservatively treated patients [60]. Surgical management of stage II pleural empyema achieves infection resolution in 88–99% of cases, with recurrence and mortality rates up to 2–4% [41]. In stage III disease, decortication yields clinical success rates of 86–95%, with satisfactory lung re-expansion in approximately 95% of cases [40].

Despite appropriate treatment, pleural infection remains potentially life-threatening. 30-day mortality can reach up to 10% in stage I, 5–10% in stage II, and 10.5% in stage III, with 1-year mortality exceeding 19% [60]. These outcomes emphasise the need for effective prognostic tools to identify high-risk patients early. Ideally, such tools should use accessible clinical and laboratory data to guide timely escalation of care, including surgery, thereby improving outcomes and reducing hospitalisation time.

The RAPID score (Renal function, Age, Purulence, Infection source, Dietary factors) was developed and prospectively validated for this purpose [27]. It stratifies patients into low (score 0–2), medium (3–4), and high-risk (5–7) categories, corresponding to 3-month mortality rates of 2.3%, 9.2%, and 29.3%, respectively. Although promising for outcome prediction, the RAPID score is not yet routinely integrated into therapeutic algorithms. Its correlation with radiological findings is limited, and further research is needed to support its implementation in clinical decision-making.

Conclusions

Outcomes in PI remain suboptimal, emphasising the need for novel therapeutic strategies. Additionally, data on long-term outcomes beyond 12 months are scarce, representing a significant gap for future investigation.

PI remains a complex clinical condition, further complicated by rising antimicrobial resistance. Diagnostic uncertainty and low microbiological yield continue to challenge clinicians, reinforcing the need to explore advanced diagnostic tools such as multiplex polymerase chain reaction and 16S rRNA gene sequencing.

Despite progress in medical therapy, timely and appropriate intervention remains crucial for improving outcomes. Surgical management has evolved significantly, offering a spectrum of effective techniques, including minimally invasive procedures, that can reduce morbidity and enhance recovery. Nevertheless, surgery alone is insufficient; optimal management depends on a comprehensive, multimodal approach.

Effective PI treatment necessitates multidisciplinary collaboration. Infectious disease specialists guide antibiotic stewardship, pulmonologists and physiotherapists support respiratory optimisation and drainage efficacy, and nutritional interventions are vital, especially for frail patients. Central to this team, thoracic surgeons lead and tailor treatment planning according to the patient's condition.

This integrated, patient-centred model holds the greatest promise for improving recovery and long-term outcomes in PI.

Key points

• Surgical intervention is indicated when medical management fails or in advanced-stage pleural infection. Video-assisted thoracoscopic surgery (VATS) is preferred in early stages, while open decortication is reserved for chronic, fibrotic disease.

• Minimally invasive innovations such as uniportal VATS, awake surgery and FlexVATS are broadening therapeutic options, particularly for high-risk or frail patients, by minimising surgical trauma and expediting recovery.

• Adjunctive and salvage procedures, including open window thoracostomy and vacuum-assisted closure (VAC) therapy, are crucial for managing refractory infections and complex empyema in critically ill or non-surgical candidates.

• Timely intervention and a multidisciplinary, patient-centred approach – integrating surgical, medical, respiratory and nutritional expertise – are essential for optimising outcomes in pleural infection.

Self-evaluation questions

1. What is the most appropriate initial treatment when frank pus is aspirated during thoracentesis?

   1. Repeat thoracentesis after 24 h
   2. Initiate corticosteroid therapy
   3. Immediate chest tube placement
   4. Schedule video-assisted thoracoscopic surgery (VATS)
   5. Observation without intervention
2. What is the appropriate first-line treatment for early-stage (stage I) pleural empyema?

   1. Surgical decortication
   2. Empirical antibiotics and thoracic drainage
   3. Intrapleural corticosteroids
   4. Repeated thoracentesis alone
   5. Open thoracotomy
3. When is surgery generally recommended for pleural empyema?

   1. Always, regardless of medical response
   2. Only after 3 weeks of antibiotics
   3. After 5–7 days of failed medical therapy
   4. When the effusion is serous
   5. Only in patients younger than 60 years of age
4. What is the first-line surgical approach for stage II empyema?

   1. Open thoracotomy
   2. Repeated aspiration
   3. Debridement and decortication via VATS
   4. Talc pleurodesis
   5. Isolated pleural lavage
5. In stage III empyema, what is considered the most effective treatment?

   1. Chest drainage with fibrinolytics
   2. VATS under local anaesthesia
   3. Thoracotomy with open surgical decortication
   4. 6-week antibiotic therapy
   5. Conservative observation

Suggested answers

1. c) Immediate chest tube placement

2. b) Empirical antibiotics and thoracic drainage

3. c) After 5–7 days of failed medical therapy

4. c) Debridement and decortication via VATS

5. c) Thoracotomy with open surgical decortication