The evolution of chest tube management following lung cancer surgery: many options, scarce evidence

Introduction

Surgery remains the treatment of choice for early-stage non-small cell lung cancer in surgically fit patients. Lung cancer surgery is most often performed using single-lung ventilation, in which only the unaffected lung is ventilated to ensure adequate oxygenation. The affected lung is deliberately collapsed to create a more accessible field and greater exposure perioperatively (1,2). As the affected lung collapses, alveolar hypoxia triggers hypoxic pulmonary vasoconstriction, which redirects pulmonary blood away from the non-ventilated lung. This physiological adaptation enhances the ventilation-perfusion ratio and thereby patients’ oxygenation during single lung ventilation (3). During thoracic surgery, the hemithorax is opened on the operated side, which allows air to enter the pleural space through the surgical incision, thereby equalizing the thoracic pressure with the atmospheric pressure, and thus creating a “deliberate” pneumothorax (4). Post-operatively, the anaesthesiologist facilitates the re-expansion of the collapsed lung by reinflation. A chest tube is then routinely placed in the pleural space to restore the negative pressure and prevent the lung from re-collapsing (5,6). In addition to the drainage of air, the placed chest tube also evacuates blood and other pleural fluids. However, chest tube placement is also associated with downsides like discomfort, pain, reduced mobility, increased risk of infection, and an extended length of hospital stay (5). In recent years, extensive research has been conducted on the use of chest tubes following lung cancer surgery. This review aims to provide an overview of the current understanding of thoracic drainage in the context of lung cancer surgery and to identify potential gaps in current knowledge, as thoracic drainage remains a cornerstone of postoperative recovery.

Evolution of chest drainage systems

The importance of drains in modern-day surgery has deep historical roots. The development of pleural or thoracic drainage systems has progressed substantially since Hippocrates first introduced the concept of drainage, using hollow tin tubes and reeds to clear empyema (470–370 BC) (7,8). Over the subsequent centuries, very little evolution regarding thoracic drainage systems has been documented. In the 13^th century, thoracic drainage through a wooden tube was described by Von Eschenbach [1170–1220], and in the 18^th century, the French military surgeon Anel [1679–1730] documented chest fluid drainage via aspiration through a syringe with several mouthpieces (9). In 1771, Birkholz improved Anel’s technique by adding a reservoir, resulting in the creation of the Potain aspirator (10). Since then, multiple adjustments have been made. In the late 19^th century, the British, German, and French physicians Playfair [1819–1894], Bülau [1835–1900], and Potain [1834–1901], respectively, practically simultaneously introduced the first underwater seal drainage device for the treatment of empyema (8,11,12). This was followed by the first use of continuous suction in 1898, described by Heaton (13).

In 1922, the American surgeon Lilienthal was a pioneer in the introduction of chest tubes following thoracic surgery, specifically after lobectomy (14). The widespread adoption of chest tubes was further reinforced by their frequent use during major military conflicts, including World War I, World War II, and the Korean War, and became the established standard of care for major thoracic surgery (15,16). The earliest drainage systems were based on a three-bottle system. Over time, the three-bottle system evolved into the modern-day analogue drainage system (Figure 1), which was first introduced in 1967 by the American company Deknatel, with all three ‘bottles’ combined in a single compact drainage unit (6,17,18). Specifically, the chest tube that is placed in the pleural cavity is connected to the first chamber, the collecting chamber, in which all pleural fluids and blood is collected. The second chamber, the water seal chamber, contains a one-way valve that allows air to be drained out of the pleural cavity during exhalation but prevents air from re-entering the pleural cavity during inhalation. The analogue drainage system’s final and third chamber is the suction control chamber, and in most cases, it is not used to apply active suction but to maintain water seal, which has been shown to be sufficient to evacuate air out of the pleural cavity. While the analogue drainage systems are still widely used, their limitations in accurate and continuous monitoring of air leaks led to the introduction of a digital drainage system in the early 2000s, with the Thopaz™ system emerging in 2007 as the first digital and portable drainage system (Figure 2A,2B) (19). In subsequent years, various other digital drainage systems, such as Drentech Redax (20) and Thoraguard (21), were introduced to the market, offering comparable solutions. The introduction of digital drainage systems after lung surgery, offering improved precision and real-time data tracking, marked the beginning of a new era.

Figure 1 Disposable analogue drainage system (Atrium Medical Corporation, Atrium Oasis Dry Suction Water Seal Chest Drain, Hudson, NH, USA).

Figure 2 Digital drainage system (Thopaz™ Chest Drain System, Medela, Switzerland). (A) System with disposable canister for patient fluid disposal; (B) display for monitoring fluid output, air leak, and pressure.

Best practices for chest tube management

Current guidelines on drain management are based on expert recommendations of the Enhanced Recovery After Surgery (ERAS) Society and European Society of Thoracic Surgeons (ESTS) (22), as well as consensus statements by the Society of Thoracic Surgeons (STS) (23). While the expert consensus documents by Batchelor et al. (22) and Kent et al. (23) were overall based on limited prospective and randomized trials, some recommendations regarding drain management are strong and evidence-based. For instance, single versus double drain insertion improves postoperative outcomes as evidenced by various randomized studies (24,25) and meta-analyses (26-28), demonstrating no significant differences in reinsertion of chest tubes or pleural effusion, while providing significantly less pain and a shorter drainage duration. Furthermore, chest tube removal criteria, particularly concerning air leakage and fluid production, are well documented. The volume threshold for chest tube removal is discussed extensively in the literature and substantiated by several prospective randomized trials and meta-analyses (29-40). Both guidelines support a volume threshold of ≤450 mL/day for safe drain removal, provided there is no bloody or chylous fluid production (24,25). To date, higher volume thresholds have not been extensively investigated; however, they may also be safe (39). Nevertheless, recent research has shown that drainage volume, rather than air leakage, is hindering early removal of the chest tube and that air leak alone can be considered a safe criterion for drain removal (38,41).

In the assessment of air leakage, the objectification differs between digital and analogue drainage systems. In analogue drainage systems, the presence of bubbles in the chamber during coughing, inspiration, and expiration indicates an air leak. In contrast, digital drainage systems provide continuous, real-time air flow (in mL/min) on the display. Chest tube removal is considered safe when the recorded flow ranges between 20 mL/min to 40 mL/min, as low flow within this range can be attributed to the physiological pleural space effect (42), or in the absence of bubbles in analogue drains (43,44). In terms of the size of the drain, a 19 to 24 French chest drain is considered appropriate after standard lobectomy by the members of the consensus panel of the STS (23), as there is only a paucity of data available on this topic. Whether it is safe to use a smaller drain (14 French) is being evaluated in an ongoing randomized phase-1 trial (45). Nevertheless, a large diameter, 28 French or greater, should only be considered in case of extensive intraoperative adhesiolyses or higher risk of postoperative haemorrhage, as a larger drain diameter goes hand in hand with higher patient discomfort and pain.

Nonetheless, two key areas warrant a more detailed discussion, as it is unclear whether their use translates into clinically significant benefits: (I) digital versus analogue drainage system, and (II) use of suction versus water seal.

Digital versus analogue drainage system

The most recent advancement in drainage systems is the digital device, which offers several theoretical benefits over the conventional analogue design. Primarily, the ability to perform real-time and continuous digital monitoring allows for an objective assessment of the possible air-leak trend and fluid production, which may improve interobserver and clinical practice variability, and thereby reduce drainage duration (6,46). Secondly, the digital drainage system is portable and lightweight, allowing early mobilization and rendering it suitable for the outpatient setting (47). Thirdly, when active suction is required, digital drainage systems do not require wall suction, as analogue systems do, due to internal suction capabilities. As such, the STS concluded that digital drainage systems are at least comparable, in terms of clinical benefits, to conventional analogue systems (23). Moreover, the ESTS strongly recommends the use of digital drains, although this is based on low-level evidence due to contradictory data (22).

The debate between digital versus analogue drainage has been a prominent topic in the last decade. Several studies, including randomized trials, have been conducted with different results. Some studies indicated no significant clinical benefit for digital drain use in terms of prolonged air leak (PAL) (48-50), drain duration, or length of hospital stay (50-55), while others did demonstrate clinically beneficial aspects of digital drainage systems compared to analogue drainage methods for the same outcome measures [i.e., PAL (56), drain duration, or length of hospital stay (57-59)]. It is important to acknowledge though, that a significant amount of heterogeneity exists concerning drain removal criteria among the aforementioned studies (e.g., clamping trials, pleural effusion volume thresholds, and post-operative X-ray assessments), complicating the comparison of clinical outcomes. Furthermore, it is common that research comparing two distinct kinds of treatment modalities is inherently subject to bias, for example, the impossibility of blinding. Hence, well-designed, prospective, randomized (controlled) trials with clear and uniform drain removal criteria are required to standardize the use of digital devices, as patients and healthcare professionals have reported higher satisfaction with digital devices (6,60). Furthermore, a recent retrospective evaluation of patients with a massive postoperative air leak (≥1,000 mL/min) has shown that massive air leakage can be managed with a digital drainage system as safely as a non-massive air leak (101–999 mL/min), without the need for surgery, as often indicated in these cases (61).

Suction versus water seal

The rationale behind the use of active suction instead of water seal is generally based on expert opinion and dogma. Nonetheless, the ESTS guidelines strongly recommend against the use of active suction, despite its theoretical role in facilitating pleura-pleural apposition, preventing persistent residual pleural space, aiding in the sealing and drainage of (large) air leaks (22). The main reason for this recommendation is that, despite conflicting data in the literature, there appears to be no clinical advantage to the application of external suction concerning length of hospital stay, air leak duration, and length of drainage (62-65). The more recent STS guideline established the consensus statement recommending an early transition from active suction to water seal when a traditional analogue drainage system and conventional chest tube are used for pleural drainage. This advice is based on six randomized controlled trials (RCTs) (66-71), three systematic reviews or meta-analyses (62,63,65), and two practical guidelines, including the ESTS guideline (22,64). However, no uniform drain management strategy was followed in the supporting RCTs. For example, in two studies, patients were immediately randomized into water seal or active suction (66,71). In two other studies, active suction [−20 cmH₂O (−2 kPa)] was applied for the first 24 hours, after which a transition to water seal was performed or active suction was continued (68,70). In another study, active suction was maintained from the operating room until arrival at the recovery unit, after which randomization was conducted into suction versus water seal (67), and in one randomized trial, water seal was immediately applied before randomization into suction versus water seal (69). Future studies should thus focus on establishing the optimal time frame in which one should transition from active suction to water seal.

Digital drainage systems apply a regulated suction mode that maintains a preset intrapleural pressure and thus do not incorporate a traditional water seal mode. Water seal mode in digital drainage systems, often referred to as gravity drainage mode, is applied through a set pressure between −2 cmH₂O (−0.2 kPa) and −8 cmH₂O (−0.8 kPa), corresponding to the physiological variations in intrapleural pressure during inspiration and expiration. This means that in the presence of an air leak, the device will exert active suction, even at very low preset suction levels. Therefore, findings from analogue systems on water seal versus suction cannot be directly extrapolated to digital drainage systems. Three RCTs (72-74) examined different suction levels between −2 cmH₂O (−0.2 kPa) and −20 cmH₂O (−2 kPa) in digital drainage systems. Due to inconsistent findings, no definitive recommendations have been established for suction levels in digital drainage systems.

Lastly, active suction might play a role in the treatment of large postoperative air leaks. Although there is no clear universal definition of a large air leak, there is some evidence that in case of a large air leak, active suction is required to generate (and restore) negative pressure, thereby promoting the drainage of both fluid and air. Furthermore, the absence of suction in this case has been shown to be associated with an increased risk of pneumonia and arrhythmia (70).

Future research directions

Despite the necessity of placing a chest tube after lung surgery procedures, notable drawbacks have also been associated with its use. The presence of a chest tube and post-operative chest pain resulting from the chest tube can significantly impact recovery and mobilisation, leading to a prolonged hospital stay (75). Early mobilisation is essential for enhancing ventilation, improving respiratory function, and preventing pneumonia (76). Additionally, it promotes lung re-expansion resulting in the decrease of a collapsed lung and atelectasis. Moreover, mobilisation reduces the risk of venous thromboembolism (VTE) in patients who are already at high risk of postoperative VTE (22,77). Lastly, prolonged chest tube insertion increases the risk of infections (78). All these negative aspects highlight the importance of timely removal of the chest tube, in accordance with the multimodal perioperative care pathway ERAS (5,75).

In addition to early chest tube removal as a means of reducing the concomitant drawbacks and risks of a chest tube, chest tube omission can also be considered in specific cases. In current clinical practice, a chest tube is routinely placed after all anatomical lung resections except pneumonectomy, as the absence of the lung reduces the potential of a pneumothorax or significant air leak (79). Contrary to anatomical resections, chest tube omission after wedge resections has been extensively examined in multiple studies and continues to be the subject of ongoing research (80). These studies found that chest tube omission in select patients after wedge resection is safe, with similar complication and reinsertion rates, but shorter hospital stay when compared to patients with chest tubes after wedge resection. Characteristics of these select patients include the absence of pleural adhesions, lung emphysema, and parenchymal defects, as well as negative results on intraoperative air leak assessments, such as the water seal test (81-83).

In line with omitting chest tubes after wedge resection, several studies have begun to explore the omission of chest tubes after anatomical resections. Initial findings suggest that, in carefully selected patients, the absence of a chest tube does not lead to an increase in complications, such as chest tube re-insertions, pneumonia, atelectasis, and empyema (84,85). However, no RCTs have been conducted yet to validate these findings, and drainless anatomical resections might not be suitable for every patient, as certain patients remain at risk for PAL and/or serious postoperative complications. Therefore, predictive parameters that are crucial to identify those patients should be investigated. Such parameters could be derived from patient characteristics, including the presence of pleural adhesions and lung emphysema, as well as from pre-existing digital drainage data such as airflow and intrapleural pressure at the end of surgery. A recently published scoping review on the use of digital drain data to predict the postoperative drainage course showed that maximum airflow peak, mean air flow, intrapleural pressure, and air leak patterns are all associated with the risk of developing PAL (86). Furthermore, digital data can objectively provide information on the timing of chest tube removal after an air leak has been discovered (87). Integrating these digital factors with patient characteristics could facilitate the development of personalized drainage strategies, optimizing postoperative drain management and patient outcomes, and potentially reducing the drainage duration and length of hospital stay.

Conclusions

In conclusion, chest drainage techniques continue to evolve, becoming less invasive with the introduction of ERAS. Standardized definitions for suction, early transition to water seal, and chest tube removal criteria should be established for the entire thoracic surgery section. Once these definitions have been formulated, future research should focus on determining the most optimal postoperative drainage strategy, identifying patients who may benefit from chest tube omission and patients who are prone to developing an air leak following anatomical resections, and creating more evidence-based recommendations and more patient-specific drainage strategies.

Acknowledgments

We thank Ernst van Loon for providing the high-quality images of the chest drains, which contributed significantly to the visual documentation in this article.

Footnote

Provenance and Peer Review: This article was commissioned by the editorial office, Translational Lung Cancer Research for the series “Current Advances and Innovations in Surgical Lung Cancer Treatment”. The article has undergone external peer review.

Peer Review File: Available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-2025-507/prf

Funding: None.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-2025-507/coif). The series “Current Advances and Innovations in Surgical Lung Cancer Treatment” was commissioned by the editorial office without any funding or sponsorship. E.R.d.L. and A.F. served as the unpaid Guest Editors of the series. K.W.E.H., Y.L.G.V., and E.R.d.L. received consulting fees from Johnson & Johnson for education in uniportal VATS lobectomy. K.W.E.H. is a board member of the Dutch Federation of Medical Specialists. The authors have no other conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Lederman D, Easwar J, Feldman J, et al. Anesthetic considerations for lung resection: preoperative assessment, intraoperative challenges and postoperative analgesia. Ann Transl Med 2019;7:356. [Crossref] [PubMed]
2. Brassard CL, Lohser J, Donati F, et al. Step-by-step clinical management of one-lung ventilation: continuing professional development. Can J Anaesth 2014;61:1103-21. [Crossref] [PubMed]
3. Tarry D, Powell M. Hypoxic pulmonary vasoconstriction. BJA Education 2017;17:208-13.
4. David P, Pompeo E, Fabbi E, et al. Surgical pneumothorax under spontaneous ventilation-effect on oxygenation and ventilation. Ann Transl Med 2015;3:106. [Crossref] [PubMed]
5. Batchelor TJP. Enhanced recovery after surgery and chest tube management. J Thorac Dis 2023;15:901-8. [Crossref] [PubMed]
6. Zisis C, Tsirgogianni K, Lazaridis G, et al. Chest drainage systems in use. Ann Transl Med 2015;3:43. [Crossref] [PubMed]
7. Christopoulou-Aletra H, Papavramidou N. "Empyemas" of the thoracic cavity in the Hippocratic Corpus. Ann Thorac Surg 2008;85:1132-4. [Crossref] [PubMed]
8. Sorino C, Feller-Kopman D, Mei F, et al. Chest Tubes and Pleural Drainage: History and Current Status in Pleural Disease Management. J Clin Med 2024;13:6331. [Crossref] [PubMed]
9. Drouin E, Wiel E, Lansiaux E, et al. Thoracentesis: an old story and some new sources. Lancet Respir Med 2025;13:16-8. [Crossref] [PubMed]
10. Walcott-Sapp, S. A History of Thoracic Drainage: From Ancient Greeks to Wound Sucking Drummers to Digital Monitoring. CTSNet 2015. doi: 10.25373/ctsnet.21291078.v1.
11. Desimonas N, Tsiamis C, Sgantzos M. The Innovated "Closed Chest Drainage System" of William Smoult Playfair (1871). Surg Innov 2019;26:760-2. [Crossref] [PubMed]
12. VašákováM, Žáčková P. Thoracic Drainage, A Step-by-Step Guide. Prague: Maxdorf; 2016.
13. Srinath N. A modified suction drainage device. Med J Armed Forces India 1995;51:51-2. [Crossref] [PubMed]
14. Scannell JG. Howard Lilienthal (1861-1946). J Thorac Cardiovasc Surg 1996;112:1681. [Crossref] [PubMed]
15. Venuta F, Diso D, Anile M, et al. Chest Tubes: Generalities. Thorac Surg Clin 2017;27:1-5. [Crossref] [PubMed]
16. Anderson D, Chen SA, Godoy LA, et al. Comprehensive Review of Chest Tube Management: A Review. JAMA Surg 2022;157:269-74. [Crossref] [PubMed]
17. French DG, Gilbert S. Technology and evidence-based care enhance postoperative management of chest drains. J Thorac Dis 2018;10:6399-403. [Crossref] [PubMed]
18. George RS, Papagiannopoulos K. Advances in chest drain management in thoracic disease. J Thorac Dis 2016;8:S55-64. [Crossref] [PubMed]
19. Medela. 10 Years of Digital Chest Drainage: Medela's Milestones Show How State-Of-The-Art Technology Has Transformed Today's Post-Operative Patient Care. 2018 (cited 2018 03 May); Available online: https://www.prnewswire.com/in/news-releases/10-years-of-digital-chest-drainage-medelas-milestones-show-how-state-of-the-art-technology-has-transformed-todays-post-operative-patient-care-681599881.html
20. Redax. Redax: Advanced drainage systems. n.d.; Available online: https://www.redax.it/en/
21. Centese. Thoraguard: Intelligent Chest Drainage System. n.d.; Available online: https://www.centese.com/thoracic-surgery/
22. Batchelor TJP, Rasburn NJ, Abdelnour-Berchtold E, et al. Guidelines for enhanced recovery after lung surgery: recommendations of the Enhanced Recovery After Surgery (ERAS®) Society and the European Society of Thoracic Surgeons (ESTS). Eur J Cardiothorac Surg 2019;55:91-115. [Crossref] [PubMed]
23. Kent MS, Mitzman B, Diaz-Gutierrez I, et al. The Society of Thoracic Surgeons Expert Consensus Document on the Management of Pleural Drains After Pulmonary Lobectomy: Expert Consensus Document. Ann Thorac Surg 2024;118:764-77. [Crossref] [PubMed]
24. Gómez-Caro A, Roca MJ, Torres J, et al. Successful use of a single chest drain postlobectomy instead of two classical drains: a randomized study. Eur J Cardiothorac Surg 2006;29:562-6. [Crossref] [PubMed]
25. Okur E, Baysungur V, Tezel C, et al. Comparison of the single or double chest tube applications after pulmonary lobectomies. Eur J Cardiothorac Surg 2009;35:32-5; discussion 35-6. [Crossref] [PubMed]
26. You J, Zhang H, Li W, et al. Single versus double chest drains after pulmonary lobectomy: a systematic review and meta-analysis. World J Surg Oncol 2020;18:175. [Crossref] [PubMed]
27. Zhang X, Lv D, Li M, et al. The single chest tube versus double chest tube application after pulmonary lobectomy: A systematic review and meta-analysis. J Cancer Res Ther 2016;12:C309-16. [Crossref] [PubMed]
28. Zhou D, Deng XF, Liu QX, et al. Single chest tube drainage is superior to double chest tube drainage after lobectomy: a meta-analysis. J Cardiothorac Surg 2016;11:88. [Crossref] [PubMed]
29. Cerfolio RJ, Bryant AS. Results of a prospective algorithm to remove chest tubes after pulmonary resection with high output. J Thorac Cardiovasc Surg 2008;135:269-73. [Crossref] [PubMed]
30. Bjerregaard LS, Jensen K, Petersen RH, et al. Early chest tube removal after video-assisted thoracic surgery lobectomy with serous fluid production up to 500 ml/day. Eur J Cardiothorac Surg 2014;45:241-6. [Crossref] [PubMed]
31. Zhang Y, Li H, Hu B, et al. A prospective randomized single-blind control study of volume threshold for chest tube removal following lobectomy. World J Surg 2014;38:60-7. [Crossref] [PubMed]
32. Xie HY, Xu K, Tang JX, et al. A prospective randomized, controlled trial deems a drainage of 300 ml/day safe before removal of the last chest drain after video-assisted thoracoscopic surgery lobectomy. Interact Cardiovasc Thorac Surg 2015;21:200-5. [Crossref] [PubMed]
33. Motono N, Iwai S, Funasaki A, et al. What is the allowed volume threshold for chest tube removal after lobectomy: A randomized controlled trial. Ann Med Surg (Lond) 2019;43:29-32. [Crossref] [PubMed]
34. Stamenovic D, Dusmet M, Schneider T, et al. A simple size-tailored algorithm for the removal of chest drain following minimally invasive lobectomy: a prospective randomized study. Surg Endosc 2022;36:5275-81. [Crossref] [PubMed]
35. Zhu J, Xia X, Li R, et al. Efficacy and safety of early chest tube removal after selective pulmonary resection with high-output drainage: A systematic review and meta-analysis. Medicine (Baltimore) 2023;102:e33344. [Crossref] [PubMed]
36. Zhang TX, Zhang Y, Liu ZD, et al. The volume threshold of 300 versus 100 ml/day for chest tube removal after pulmonary lobectomy: a meta-analysis. Interact Cardiovasc Thorac Surg 2018;27:695-702. [Crossref] [PubMed]
37. Miserocchi G, Beretta E, Rivolta I. Respiratory mechanics and fluid dynamics after lung resection surgery. Thorac Surg Clin 2010;20:345-57. [Crossref] [PubMed]
38. Takamochi K, Haruki T, Oh S, et al. Early chest tube removal regardless of drainage volume after anatomic pulmonary resection: A multicenter, randomized, controlled trial. J Thorac Cardiovasc Surg 2024;168:401-410.e1. [Crossref] [PubMed]
39. Mesa-Guzman M, Periklis P, Niwaz Z, et al. Determining optimal fluid and air leak cut off values for chest drain management in general thoracic surgery. J Thorac Dis 2015;7:2053-7. [Crossref] [PubMed]
40. Gioutsos K, Ehrenreich L, Azenha LF, et al. Randomized Controlled Trial of Thresholds for Drain Removal After Anatomic Lung Resection. Ann Thorac Surg 2024;117:1103-9. [Crossref] [PubMed]
41. Abdul Khader A, Pons A, Palmares A, et al. Outcomes of chest drain management using only air leak (without fluid) criteria for removal after general thoracic surgery-a drainology study. J Thorac Dis 2023;15:3776-82. [Crossref] [PubMed]
42. Marasco RD, Giudice G, Lequaglie C. How to distinguish an active air leak from a pleural space effect. Asian Cardiovasc Thorac Ann 2012;20:682-8. [Crossref] [PubMed]
43. Dugan KC, Laxmanan B, Murgu S, et al. Management of Persistent Air Leaks. Chest 2017;152:417-23. [Crossref] [PubMed]
44. Embalabala A, Mitzman B, Crabtree T. Digital pleural versus analog drainage devices for postoperative management of patients after pulmonary resection. Eur J Cardiothorac Surg 2025;67:i31-40. [Crossref] [PubMed]
45. Stamenovic D, Dittmar E, Schiller P, et al. A randomized controlled trial: Comparison of 14 and 24 French thoracic drainage after minimally invasive lobectomy - MZ 14-24 study. Heliyon 2023;9:e22049. [Crossref] [PubMed]
46. Honda T, Tauchi S. Chest drainage outcomes by water seal versus low suction on digital drainage systems after lung resection: retrospective study. J Thorac Dis 2024;16:6644-50. [Crossref] [PubMed]
47. Danitsch D. Benefits of digital thoracic drainage systems. Nurs Times 2012;108:16-7.
48. Bertolaccini L, Rizzardi G, Filice MJ, et al. 'Six sigma approach' - an objective strategy in digital assessment of postoperative air leaks: a prospective randomised study. Eur J Cardiothorac Surg 2011;39:e128-32. [Crossref] [PubMed]
49. Chiappetta M, Lococo F, Nachira D, et al. Digital Devices Improve Chest Tube Management: Results from a Prospective Randomized Trial. Thorac Cardiovasc Surg 2018;66:595-602. [Crossref] [PubMed]
50. Adachi H, Wakimoto S, Ando K, et al. Optimal Chest Drainage Method After Anatomic Lung Resection: A Prospective Observational Study. Ann Thorac Surg 2023;115:845-52. [Crossref] [PubMed]
51. Mendogni P, Tosi D, Marulli G, et al. Multicenter randomized controlled trial comparing digital and traditional chest drain in a VATS pulmonary lobectomy cohort: interim analysis. J Cardiothorac Surg 2021;16:188. [Crossref] [PubMed]
52. Plourde M, Jad A, Dorn P, et al. Digital Air Leak Monitoring for Lung Resection Patients: A Randomized Controlled Clinical Trial. Ann Thorac Surg 2018;106:1628-32. [Crossref] [PubMed]
53. Takamochi K, Nojiri S, Oh S, et al. Comparison of digital and traditional thoracic drainage systems for postoperative chest tube management after pulmonary resection: A prospective randomized trial. J Thorac Cardiovasc Surg 2018;155:1834-40. [Crossref] [PubMed]
54. Gilbert S, McGuire AL, Maghera S, et al. Randomized trial of digital versus analog pleural drainage in patients with or without a pulmonary air leak after lung resection. J Thorac Cardiovasc Surg 2015;150:1243-9. [Crossref] [PubMed]
55. Lijkendijk M, Licht PB, Neckelmann K. Electronic versus traditional chest tube drainage following lobectomy: a randomized trial. Eur J Cardiothorac Surg 2015;48:893-8; discussion 898. [Crossref] [PubMed]
56. De Waele M, Agzarian J, Hanna WC, et al. Does the usage of digital chest drainage systems reduce pleural inflammation and volume of pleural effusion following oncologic pulmonary resection?-A prospective randomized trial. J Thorac Dis 2017;9:1598-606. [Crossref] [PubMed]
57. Cerfolio RJ, Bryant AS. The benefits of continuous and digital air leak assessment after elective pulmonary resection: a prospective study. Ann Thorac Surg 2008;86:396-401. [Crossref] [PubMed]
58. Filosso PL, Nigra VA, Lanza G, et al. Digital versus traditional air leak evaluation after elective pulmonary resection: a prospective and comparative mono-institutional study. J Thorac Dis 2015;7:1719-24. [Crossref] [PubMed]
59. Comacchio GM, Marulli G, Mendogni P, et al. Comparison Between Electronic and Traditional Chest Drainage Systems: A Multicenter Randomized Study. Ann Thorac Surg 2023;116:104-9. [Crossref] [PubMed]
60. Yu PS, Chan KW, Lim K, et al. Lower Recurrence Rate After Surgical Treatment for Primary Spontaneous Pneumothorax Using a Digital Chest Drainage System. Innovations (Phila) 2024;19:390-4. [Crossref] [PubMed]
61. Ueda T, Takamochi K, Hattori A, et al. Postoperative management using a digital drainage system for massive air leakage after pulmonary resection. Surg Today 2024;54:130-7. [Crossref] [PubMed]
62. Coughlin SM, Emmerton-Coughlin HM, Malthaner R. Management of chest tubes after pulmonary resection: a systematic review and meta-analysis. Can J Surg 2012;55:264-70. [Crossref] [PubMed]
63. Deng B, Tan QY, Zhao YP, et al. Suction or non-suction to the underwater seal drains following pulmonary operation: meta-analysis of randomised controlled trials. Eur J Cardiothorac Surg 2010;38:210-5. [Crossref] [PubMed]
64. Gao S, Zhang Z, Aragón J, et al. The Society for Translational Medicine: clinical practice guidelines for the postoperative management of chest tube for patients undergoing lobectomy. J Thorac Dis 2017;9:3255-64. [Crossref] [PubMed]
65. Qiu T, Shen Y, Wang MZ, et al. External suction versus water seal after selective pulmonary resection for lung neoplasm: a systematic review. PLoS One 2013;8:e68087. [Crossref] [PubMed]
66. Cerfolio RJ, Bass C, Katholi CR. Prospective randomized trial compares suction versus water seal for air leaks. Ann Thorac Surg 2001;71:1613-7. [Crossref] [PubMed]
67. Marshall MB, Deeb ME, Bleier JI, et al. Suction vs water seal after pulmonary resection: a randomized prospective study. Chest 2002;121:831-5. [Crossref] [PubMed]
68. Brunelli A, Monteverde M, Borri A, et al. Comparison of water seal and suction after pulmonary lobectomy: a prospective, randomized trial. Ann Thorac Surg 2004;77:1932-7; discussion 1937. [Crossref] [PubMed]
69. Alphonso N, Tan C, Utley M, et al. A prospective randomized controlled trial of suction versus non-suction to the under-water seal drains following lung resection. Eur J Cardiothorac Surg 2005;27:391-4. [Crossref] [PubMed]
70. Gocyk W, Kużdżał J, Włodarczyk J, et al. Comparison of Suction Versus Nonsuction Drainage After Lung Resections: A Prospective Randomized Trial. Ann Thorac Surg 2016;102:1119-24. [Crossref] [PubMed]
71. Prokakis C, Koletsis EN, Apostolakis E, et al. Routine suction of intercostal drains is not necessary after lobectomy: a prospective randomized trial. World J Surg 2008;32:2336-42. [Crossref] [PubMed]
72. Brunelli A, Salati M, Pompili C, et al. Regulated tailored suction vs regulated seal: a prospective randomized trial on air leak duration. Eur J Cardiothorac Surg 2013;43:899-904. [Crossref] [PubMed]
73. Lijkendijk M, Licht PB, Neckelmann K. The Influence of Suction on Chest Drain Duration After Lobectomy Using Electronic Chest Drainage. Ann Thorac Surg 2019;107:1621-5. [Crossref] [PubMed]
74. Holbek BL, Christensen M, Hansen HJ, et al. The effects of low suction on digital drainage devices after lobectomy using video-assisted thoracoscopic surgery: a randomized controlled trial†. Eur J Cardiothorac Surg 2019;55:673-81. [Crossref] [PubMed]
75. Li P, Li S, Che G. Role of chest tube drainage in physical function after thoracoscopic lung resection. J Thorac Dis 2019;11:S1947-50. [Crossref] [PubMed]
76. Rogers LJ, Bleetman D, Messenger DE, et al. The impact of enhanced recovery after surgery (ERAS) protocol compliance on morbidity from resection for primary lung cancer. J Thorac Cardiovasc Surg 2018;155:1843-52. [Crossref] [PubMed]
77. Wang P, Zhao H, Zhao Q, et al. Risk Factors and Clinical Significance of D-Dimer in the Development of Postoperative Venous Thrombosis in Patients with Lung Tumor. Cancer Manag Res 2020;12:5169-79. [Crossref] [PubMed]
78. Minervini F, Hanna WC, Brunelli A, et al. Outcomes of patients discharged home with a chest tube after lung resection: a multicentre cohort study. Can J Surg 2022;65:E97-E103. [Crossref] [PubMed]
79. Morcos K, Shaikhrezai K, Kirk AJ. Is it safe not to drain the pneumonectomy space? Interact Cardiovasc Thorac Surg 2014;18:671-5. [Crossref] [PubMed]
80. Holbek BL, Huang L, Christensen TD, et al. Efficacy of avoiding chest drains after video-assisted thoracoscopic surgery wedge resection: protocol for a randomised controlled trial. BMJ Open 2024;14:e080573. [Crossref] [PubMed]
81. Laven IEWG, Daemen JHT, Janssen N, et al. Risk of Pneumothorax Requiring Pleural Drainage after Drainless VATS Pulmonary Wedge Resection: A Systematic Review and Meta-Analysis. Innovations (Phila) 2022;17:14-24. [Crossref] [PubMed]
82. Laven IEWG, Franssen AJPM, van Dijk DPJ, et al. A No-Chest-Drain Policy After Video-assisted Thoracoscopic Surgery Wedge Resection in Selected Patients: Our 12-Year Experience. Ann Thorac Surg 2023;115:835-43. [Crossref] [PubMed]
83. Li P, Shen C, Wu Y, et al. It is safe and feasible to omit the chest tube postoperatively for selected patients receiving thoracoscopic pulmonary resection: a meta-analysis. J Thorac Dis 2018;10:2712-21. [Crossref] [PubMed]
84. Murakami J, Ueda K, Tanaka T, et al. The Validation of a No-Drain Policy After Thoracoscopic Major Lung Resection. Ann Thorac Surg 2017;104:1005-11. [Crossref] [PubMed]
85. Ueda K, Hayashi M, Tanaka T, et al. Omitting chest tube drainage after thoracoscopic major lung resection. Eur J Cardiothorac Surg 2013;44:225-9; discussion 229. [Crossref] [PubMed]
86. Verkoulen KCHA, Laven IEWG, Daemen JHT, et al. From data to prediction: Digital chest drain insights into postoperative recovery after lung cancer surgery. Lung Cancer 2025;202:108486. [Crossref] [PubMed]
87. Takamochi K, Imashimizu K, Fukui M, et al. Utility of Objective Chest Tube Management After Pulmonary Resection Using a Digital Drainage System. Ann Thorac Surg 2017;104:275-83. [Crossref] [PubMed]