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Background: We aimed to evaluate the epidemiological characteristics, risk factors and prognostic factors affecting the clinical follow-up of patients who underwent tube thoracostomy due to pneumothorax in the neonatal intensive care unit of our hospital. Methods: In our study; 54 cases with neonatal pneumothorax underwent tube thoracostomy followed up in the neonatal intensive care unit between April 2014 and March 2023 were retrospectively analyzed. Results: The gestational age of the cases was between 28 and 38 weeks; 24 (44.4%) were premature and 30 (55.6%) were 36 weeks and above. Of the cases included in the study, 35 (64.8%) had primary lung disease and 19 (35.2%) had other anomalies accompanying pneumothorax. Mechanical ventilation was needed in 35 (64.8%) of the 54 cases included in the study. While all patients who did not require mechanical ventilation recovered, 10 of 35 patients (28.6%) who required mechanical ventilation died. The body weight of 10 of these 35 cases (28.6%) was 2500 g or less. Conclusion: It was determined that accompanying primary lung disease, the need to connect to a ventilator, and bilateral pneumothorax significantly affected mortality and prognosis in premature babies, especially those weighing less than 2500 g, who were followed in the neonatal intensive care unit. [ABSTRACT FROM AUTHOR]

Objective: This study presents DraiNet, a deep learning model developed to detect pneumothorax and pleural effusion in pediatric patients and aid in assessing the necessity for tube thoracostomy. The primary goal is to utilize DraiNet as a decision support tool to enhance clinical decision-making in the management of these conditions. Methods: DraiNet was trained on a diverse dataset of pediatric CT scans, carefully annotated by experienced surgeons. The model incorporated advanced object detection techniques and underwent evaluation using standard metrics, such as mean Average Precision (mAP), to assess its performance. Results: DraiNet achieved an impressive mAP score of 0.964, demonstrating high accuracy in detecting and precisely localizing abnormalities associated with pneumothorax and pleural effusion. The model's precision and recall further confirmed its ability to effectively predict positive cases. Conclusion: The integration of DraiNet as an AI-driven decision support system marks a significant advancement in pediatric healthcare. By combining deep learning algorithms with clinical expertise, DraiNet provides a valuable tool for non-surgical teams and emergency room doctors, aiding them in making informed decisions about surgical interventions. With its remarkable mAP score of 0.964, DraiNet has the potential to enhance patient outcomes and optimize the management of critical conditions, including pneumothorax and pleural effusion. [ABSTRACT FROM AUTHOR]

Objective: This study presents DraiNet, a deep learning model developed to detect pneumothorax and pleural effusion in pediatric patients and aid in assessing the necessity for tube thoracostomy. The primary goal is to utilize DraiNet as a decision support tool to enhance clinical decision-making in the management of these conditions. Methods: DraiNet was trained on a diverse dataset of pediatric CT scans, carefully annotated by experienced surgeons. The model incorporated advanced object detection techniques and underwent evaluation using standard metrics, such as mean Average Precision (mAP), to assess its performance. Results: DraiNet achieved an impressive mAP score of 0.964, demonstrating high accuracy in detecting and precisely localizing abnormalities associated with pneumothorax and pleural effusion. The model's precision and recall further confirmed its ability to effectively predict positive cases. Conclusion: The integration of DraiNet as an AI-driven decision support system marks a significant advancement in pediatric healthcare. By combining deep learning algorithms with clinical expertise, DraiNet provides a valuable tool for non-surgical teams and emergency room doctors, aiding them in making informed decisions about surgical interventions. With its remarkable mAP score of 0.964, DraiNet has the potential to enhance patient outcomes and optimize the management of critical conditions, including pneumothorax and pleural effusion. [ABSTRACT FROM AUTHOR]

Purpose: Pneumothorax is defined as the presence of air between the parietal and visceral leaves of the pleura, resulting in lung collapse. The aim of this study was to evaluate the respiratory functions of these patients when they reach school age and to reveal whether they cause permanent respiratory pathology. Methods: The files of 229 patients who were hospitalised in a neonatal intensive care clinic had received a diagnosis of pneumothorax and had undergone tube thoracostomy were included in a retrospective cohort review. The respiratory functions of participants in the control and patient groups were evaluated using spirometry in a prospective cross-sectional study design. Results: The study found the rates of pneumothorax to be higher in males, term infants and after caesarean delivery, mortality was 31%. Among patients who underwent spirometry, those with a history of pneumothorax had lower forced expiratory volume at timed intervals of 0.5 to 1.0 (FEV1), forced vital capacity (FVC), FEV1/FVC, peak expiratory flow (PEF) and forced expiratory flow 25–75% (MEF25-75). FEV1/FVC ratio was significantly lower (p < 0.05). Conclusion: Patients treated for pneumothorax in the neonatal period should be evaluated for obstructive pulmonary diseases during childhood using respiratory function tests. [ABSTRACT FROM AUTHOR]

The concept of massive pleurisy (MP) is frequently used to emphasize the significance of the amount of pleural effusion. However, there are significant disagreements about it due to the lack of a universal definition for MP. In our study, we sought to elucidate these distinctions. We employed a questionnaire comprised of visual and true/false sections. In the visual section, participants were shown real-time lung radiographs and schematic drawings and asked which ones were MP. On the other hand, suggestions regarding diagnosis, treatment, and consultations for MP were questionnaired. The study was comprised of 150 physicians from four distinct centers. On true/false and radiograph questions, physicians from the same branch exhibited differences of up to 50% (p < 0.05). On the level question, each branch involved reached a consensus (p = 0.003). In questions 3, 4, and 5, which also contained a true–false section, the branches gave varying responses, with the exception of the opinion that tube thoracostomy is unquestionably indicated in MP (p < 0.05). Establishing a common language for MP is crucial for clinician collaboration and appropriate patient management. Our study elucidates the divergences of opinion between branches and highlights the need for a unified definition. [ABSTRACT FROM AUTHOR]

Purpose: Tube thoracostomy (TT) is a simple and a life-saving procedure; nevertheless, it carries morbidity, even after its removal. Currently, TT is managed and removed by chest X-ray (CXR) evaluation. There are limitations and these are directly linked to complications. The use of thoracic ultrasound (US) has already been established in the diagnosis of pneumothorax (PTX) and hemothorax (HTX); its use, in substitution of CXR can lead to improvement in care. Our aim is to evaluate the efficiency and safety of US in the management of TT. Methods: Prospective and randomized study with patients requiring TT. They were divided in groups according to their thoracic injuries (PTX and HTX) and randomized into two groups according to TT management: US and CXR. Data collected included gender, age, mechanism of injury, days to TT removal, complications after TT removal and presence of mechanical ventilation. Results: Sixty-one patients were randomized, of which 68.8% were male. The most frequent diagnosis was PTX, present in 37 cases. Median time for TT removal was 2.5 days in the US group and 4.9 in the control group (p = 0.009). The complication rate was 6.6%, with no morbidity in the US group. TT removal in patients with mechanical ventilation did not increase the incidence of complications. Conclusions: The use of US in the management is efficient and safe. It allows early TT removal regardless the cause of the thoracic injury. [ABSTRACT FROM AUTHOR]

Purpose: Whole-body computed tomography (CT) for blunt trauma patients is common. Chest CT (CCT) identifies "occult" pneumo- (PTX) and hemothorax (HTX) not seen on chest radiograph (CXR), one-third of whom get chest tubes, while CXR identifies "non-occult" PTX/HTX. To assess chest tube value for occult injury vs. expectant management, we compared output, duration, and length of stay (LOS) for chest tubes placed for occult vs. non-occult (CXR-visible) injury. Methods: We compared chest tube output and duration, and patient length of stay for occult vs. non-occult PTX/HTX. This was a retrospective analysis of 5451 consecutive Level I blunt trauma patients, from 2010 to 2013. Results: Of these blunt trauma patients, 402 patients (7.4%) had PTX, HTX or both, and both CXR and CCT. One third (n = 136, 33.8%) had chest tubes placed in 163 hemithoraces (27 bilateral). Non-occult chest tube output for all patients was 1558 ± 1919 cc (n = 54), similar to occult at 1123 ± 1076 cc (n = 109, p = 0.126). Outputs were similar for HTX-only patients, with non-occult (n = 34) at 1917 ± 2130 cc, vs. occult (n = 54) at 1449 ± 1131 cc (p = 0.24). Chest tube duration for all patients was 6.3 ± 4.9 days for non-occult vs. 5.0 ± 3.3 for occult (p = 0.096). LOS was similar between all occult injury patients (n = 46) and non-occult (n = 90, 17.0 ± 15.8 vs. 13.7 ± 11.9 days, p = 0.23). Conclusion: Mature clinical judgment may dictate which patients need chest tubes and explain the similarity between groups. [ABSTRACT FROM AUTHOR]

Background: Coronavirus disease 2019 (COVID-19) is a newly emerging infectious disease that was first reported in China and has become a worldwide pandemic. Many surgical procedures are continuing to be performed during this state of pandemic as is thoracic surgery. We present six cases of tube thoracostomy in COVID-19 patients and the modifications to the routine surgical technique. Methods: We serially attached two closed underwater drainage systems (CUDS) together and added a high-efficiency particulate air (HEPA) filter to the port of the second CUDS, because the intrapleural air, which passes through the CUDS into the air in intensive care unit (ICU), may contain high concentrations of 2019 novel coronavirus (2019-nCoV). Second, we attached the chest drain to the first CUDS in order to prevent the spread of virus during the placement of drain into the pleural cavity. Third, just before opening the parietal pleura, ventilation was put on standby mode and the endotracheal tube was clamped to prevent viral dissemination to the environment. Fourth, we covered the incision with a gauze sponge soaked with sterile saline solution during pleural entry, to prevent viral dissemination into the environment. Results: There were a total of six patients enrolled in our study. All these patients were diagnosed with COVID-19. The surgical indication for the chest tube thoracostomy was tension pneumothorax in all six patents. All patients had lung expansion defects and subcutaneous emphysema after intervention. Unfortunately, all of them succumbed to COVID-19, despite best available treatment. There was no COVID-19 infection reported in the healthcare professionals during this study. Conclusions: Thoracic surgical procedures may cause dissemination of high amounts of 2019-nCoV in the environment and thus are perhaps the most dangerous surgeries to perform. Variations in the thoracic surgical techniques are necessary in order to protect the healthcare providers from COVID-19. [ABSTRACT FROM AUTHOR]

Purpose: Tube thoracostomy is frequently used in thoracic trauma patients. However, there is no consensus on whether low pressure suction or water seal is the optimal method of tube management. Against this background, we performed a systematic review of studies comparing suction and water seal management of chest tubes placed for traumatic chest injuries in adults. Evaluated outcomes are duration of chest tube treatment, length of stay in hospital, incidence of persistent air leak, clotted hemothorax, and the need for (re-)interventions.Methods: A systematic literature search according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines was performed. Included studies were evaluated according to the Cochrane Collaboration’s tool for assessing the risk of bias, and according to Grading of Recommendations Assessment, Development and Evaluation (GRADE) guidelines for assessing the quality of evidence.Results: After assessment of 120 identified studies, three RCT’s (randomized controlled trials) were included in this review and meta-analysis. A favorable effect of suction was found for duration of chest tube treatment [MD (mean difference) − 3.38 days, P = 0.005], length of stay in hospital (MD −3.90 days, P = 0.0003), and the incidence of persistent air leak [OR (odds ratio) 0.27, P = 0.001]. No significant difference was found for the incidence of clotted hemothorax and (re-)interventions. The quality of evidence according to GRADE was low, except for persistent air leak (moderate).Conclusions: Suction seems to have a positive effect on duration of chest tube treatment, length of stay in hospital and persistent air leakage in chest trauma. However, available data was limited and the quality of evidence was (very) low to moderate according to GRADE. [ABSTRACT FROM AUTHOR]

Purpose: Complicated parapneumonic effusions and empyema are a leading cause of morbidity in the United States with over 1 million admissions annually and a mortality rate that remains high in spite of recent advances in diagnosis and treatment. The identification of high risk patients is crucial for improved management and the provision of cost-effective care. The RAPID score is a scoring system comprised of the following variables: renal function, age, purulence, infection source, and dietary factors and has been shown to predict outcomes in patients with pleural space infections.Methods: In a single center retrospective study, we evaluated 98 patients with complicated parapneumonic effusions and empyema who had tube thoracostomy (with or without Intrapleural fibrinolytic therapy) and assessed treatment success rates, mortality, length of hospital stay, and direct hospitalization costs stratified by three RAPID score categories: low-risk (0-2), medium risk (3-4), and high-risk (5-7) groups.Results: Treatment success rate was 71%, and the 90 day mortality rate was 12%. There was a positive-graded association between the low, medium and high RAPID score categories and mortality, (5.3%, 8.3% and 22.6%, respectively), length of hospital stay (10, 21, 19 days, respectively), and direct hospitalization costs ($19,909, $36,317 and $43,384, respectively).Conclusion: Our findings suggest that the RAPID score is a robust tool which could be used to identify patients with complicated parapneumonic effusions and empyema who may be at an increased risk of mortality, prolonged hospitalization, and who may incur a higher cost of treatment. Randomized controlled trials identifying the most effective initial treatment modality for medium- and high-risk patients are needed. [ABSTRACT FROM AUTHOR]

Purpose: Hemo/pneumothoraces are a common result of thoracic injury. Some of these injuries will be complicated by retained hemothorax (RH), which has previously been shown to be associated with longer hospitalizations. It has been proposed that early versus delayed intervention with video-assisted thoracoscopic surgery can reduce the duration of mechanical ventilation, hospital and ICU LOS, and costs in patients with RH. However, little is known regarding the effect of RH on these outcomes relative to patients with uncomplicated hemo/pneumothoraces. The aim of our study was to characterize factors present on admission that may be associated with RH and assess the impact of RH on outcomes. Methods: A retrospective chart review was conducted and included all patients who underwent tube thoracostomy (TT) for traumatic hemo/pneumothorax admitted to a single urban adult and pediatric level I trauma center from January 2008 to September 2013. Results: The study cohort included 398 patients, 17.6 % developed RH. RH was associated with significantly longer total duration of TT drainage ( p < 0.001), hospital LOS ( p < 0.001), and total hospital charges ( p < 0.001). These associations remained significant in a subgroup analysis excluding patients with traumatic brain injury. Patients with bilateral injuries (OR 4.25, p < 0.001) and patients intubated on the day of admission (OR 2.30, p = 0.002) were significantly more likely to develop RH. There was also a small, but highly significant, association between increasing ISS and the development of RH (OR 1.07, p < 0.001). Conclusions: Our study suggests patients requiring ventilator support on admission and those with bilateral injuries are at increased risk of developing RH. Early identification of patients at risk for RH may allow for earlier intervention and potential benefits to the patient. [ABSTRACT FROM AUTHOR]

Patients with thoracic trauma constitute one third of all the trauma cases. Of traumatic patients, 20-25 % die because of thoracic trauma. Our aim was to compare our clinical experience and the results with the related literature. Four hundred thirty-three patients, who underwent surgical interventions due to thoracic trauma, were evaluated. The latest form of treatment applied were taken as the criteria for the quantitative detection of patients. Continuous variables were expressed as mean ± standard deviation, while categorical variables were explained as number and percentage. The significance of the analysis results was evaluated using Fisher's exact test. p values <0.05 were considered as significant. Penetrating injuries were found in 258 (59 %) of the patients, and blunt trauma was identified in 175 (41 %). Depending on the trauma, pneumothorax was discovered in 130 patients (30.02 %), hemothorax in 117 (27.02 %), hemopneumothorax in 61 (14.08 %), pulmonary contusion in 110 (45 %), pneumomediastinum in 14 (3.23 %), and pericardial tamponade in 1 patient (0.23 %). It was demonstrated that 385 of 433 patients examined in the study underwent tube thoracostomy, 41 were treated with thoracotomy, while 6 of them underwent video-assisted thoracoscopic surgery (VATS), and 1 underwent sternotomy. No correlation was observed between mortality, morbidity, and gender and type of trauma and location of trauma ( p > 0.05). However, statistically significant correlation was found between mortaxlity, morbidity, and the presence of concomitant injuries, the duration between injury and admission being more than 1 h ( p < 0.05). Urgent intervention, early diagnosis, and fast transport are vital for patients with thoracic injuries. [ABSTRACT FROM AUTHOR]

Introduction/background: Occult pneumothorax (OPTX) is defined as air within the pleural cavity that is undetectable on normal chest X-rays, but identifiable on computed tomography. Currently, consensus is divided between tube thoracostomy and conservative management for OPTX. Methods: The aim of this retrospective study is to determine whether OPTX can be managed conservatively and whether any adverse events occur under conservative management. Data on all trauma patients from 1 Jan 2010 to 31 December 2012 were obtained from our hospital's trauma registry. All patients with occult pneumothorax who had chest X-ray (CXR) and any CT scan visualizing the thorax were included. The exclusion criteria included those with penetrating wounds; CXR showing pneumothorax, hemothorax, or hemopneumothorax; those with prophylactic chest tube insertion before CT; and those with no CT diagnosis of OPTX. The complications of these patients were analyzed to determine if tube thoracostomy is necessary for OPTX and whether not inserting it would alter the outcome significantly. Results: A total of 1564 cases were reviewed and 83 patients were included. Of these 83 patients, 35 (42.2 %) had tube thoracostomy after OPTX detection and 48 (57.8 %) were observed initially. Patients who had tube thoracostomy had similar ISS compared to those without (median ISS 17 vs. 18.5, p = 0.436). Out of the 48 patients who did not have tube thoracostomy on detection of an OPTX, 4 (8.3 %) had complications. In the group of 35 patients who had tube thoracostomy on detection of an OPTX, 7 (20 %) had complications. Of the 83 patients, a total of 12 patients had IPPV, of which 7 (58.3 %) had tube thoracostomy and 5 (41.7 %) did not. Patients who had tube thoracostomy under our care have a statistically significant likelihood of experiencing any complication compared to those without tube thoracostomy (odds ratio 9.92. The median length of stay was also longer (13 days) in those who had tube thoracostomy compared to those without (5 days) ( p value = 0.008). Conclusions: Our study suggests that patients with OPTX can be managed conservatively with close monitoring, but only in areas with ready access to emergency facilities should any adverse events occur. [ABSTRACT FROM AUTHOR]

Background: Primary spontaneous pneumothorax (PSP) is a critical clinical problem, and its incidence is increasing. The risk of recurrence is high. Factors which may or may not predispose to recurrence have not yet been established. Methods: Over a period of 4 years, 78 cases with a diagnosis of PSP were reviewed, and the following variables were analysed: age, sex, history of smoking and the type of treatment. Results: The majority of the patients (79.48 %) were below the age of 40 years, with a male gender predominance (91 %). Three quarters of the males were smokers while the females were not smokers. The left side pneumothorax was more common than the right (55.12 vs 44.88 %), and chest pain was the commonest complaint-57.7%. Most of the patients (92.3 %) were treated with insertion of intercostal thoracostomy tube only (6.42 %). Those who showed failure of thoracostomy tube were treated by open thoracotomy. A total of 1.3 % of the patients were unfit for surgery and were treated with chemical pleurodesis. The recurrence rate after thoracostomy tube only was 15.5 %, while there was no recurrence after surgery and chemical pleurodesis. The indications of surgery were continuous air leak more than 10 days (5 cases), recurrence in the contralateral side (one case) and frequent recurrences (one case). Conclusion: PSP is a disease of young males, with chest pain as the most common presenting symptom. Intercostal thoracostomy tube and thoracotomy are effective treatment with low rate of recurrence in areas of lack of facility. [ABSTRACT FROM AUTHOR]

Background: Injuries are one of the leading causes of morbidity and mortality around the world, and their burden is expected to rise dramatically by the year 2020. Tube thoracostomy is the most widely performed procedure for management of blunt and penetrating chest traumas and has a pivotal role in their management. Chest tube (Ct) drain output is the main determinant in the management and removal of chest tube. The present study was conducted to correlate drainage volume with timing of chest tube removal, with an aim to establish a safe drainage volume for chest tube removal. Materials and methods: This study was conducted after ethical clearance in a tertiary care hospital on 150 patients of blunt thoracic trauma who underwent tube thoracostomy for hemopneumothorax between August 2011 and December 2012. Patients were planned for sequence randomization in three groups, viz. group A, group B, and group C, in which chest tubes were planned to be removed at a drainage output of 50 ml in group A, 100 ml drainage output in group B, and 150 ml drainage output in group C, with 50 patients in each group. Result: Rate of re-accumulation after chest tube removal did not differ significantly among the three groups ( p > 0.05). Total significant re-accumulation rate (for which aspiration was required) was 5.8 % in group A, 5.7 % in group B, and 5.8 % in group C, respectively Conclusion: Drainage volume of 150 ml at the time of chest tube removal has no impact on re-accumulation and is not associated with any increase in morbidity. It is associated with a shorter hospital stay. [ABSTRACT FROM AUTHOR]

Purpose: Safe intrathoracic placement of chest tubes is a continual challenge. Current techniques for determining the intrathoracic location of the thoracostomy site include blunt dissection and digital exploration, with subsequent tube placement. Using current techniques, complication rates for this procedure approach 30 %. We present a novel technique using available endotracheal intubation technology for determining intrathoracic placement of tube thoracostomy. Methods: One cadaver was used for placement of tube thoracostomy. Both sides of the thorax were prepared in the standard fashion for tube thoracostomy placement, and tube thoracostomy was performed on each hemithorax at interspaces 3 through 7. The right side of the thorax was used for standard thoracostomy placement, and the left side was used for fiberoptic visualization of thoracostomy placement using a video laryngoscope. Thoracic wall thickness was measured at all thoracostomy sites. Proper placement and any injuries were documented for each site. Results: Chest wall thickness ranged from 2.4 to 3.8 cm on the right and 2.8 to 4.0 cm on the left. With use of fiberoptic thoracostomy, no injuries were generated. During the standard thoracostomy placement in the sixth intercostal space, a pulmonary laceration was caused using blunt dissection. Conclusions: Use of a fiberoptic laryngoscope offers a novel technique for direct visualization the thoracic space during tube thoracostomy. Further studies are needed to determine the safety of this technique in patients. [ABSTRACT FROM AUTHOR]

Objective: To identify risk factors associated with the development of post-traumatic retained hemothorax in chest trauma patients admitted to Hospital San Vicente de Paul (HUSVP). Methods: This study was a prospective cohort study that included patients with a diagnosis of chest trauma who required a tube thoracostomy as a therapeutic intervention. The measured outcome was retained hemothorax, defined as the presence of blood in the pleural cavity that could not be drained through the initial tube thoracostomy and appeared radio-opaque or hypodense on X-rays or CT scan. The postoperative follow-up period was 30 days. Results: Six hundred thirty-three thoracostomies were performed over a 28-month period for chest trauma; the incidence of post-traumatic retained hemothorax was 16.7%, and additional complications were seen in 10% of cases. The risk of retained hemothorax was associated with: initial blood drainage (median, 400 ml; p < 0.001), the number of tubes placed (two or more; OR = 5.35, CI 95%: 3.98-7.20), the duration of the tube thoracostomy (median, 5 days; p = 0.01), and the need for mechanical ventilation (RR = 2.5, CI 95%: 1.66-3.75). Conclusions: The risk of post-traumatic retained hemothorax was associated with four factors. The probability of the outcome could be modified by careful monitoring, management protocols, suction through the tube thoracostomy, and maybe an early intervention, such as thoracoscopy. [ABSTRACT FROM AUTHOR]

Pleural effusions are a severe complication of advanced malignant disease. Palliative treatment strategies should be simple and effective. We investigated iodized talc pleurodesis through tube thoracostomy for this purpose. A total of 43 patients received a suspension of 5 g talc with 3 g thymol iodine via chest tube. The procedure was well tolerated without major complications in all cases. Unfortunately, 4 patients died of disease within the 1st month after treatment, so that only 39 patients were evaluable for treatment outcome. Follow-up ranged from 1 to 14 months. The success rate after 3 months was 92.5%. In conclusion, iodized talc pleurodesis is an excellent tool in the palliative management of malignant pleural effusions. Administration via chest tube is sufficient for treatment success. [ABSTRACT FROM AUTHOR]

A simple and safe technique for accurate placement of intercostal drainage tubes with the help of metal urethral dilators is described. [ABSTRACT FROM AUTHOR]

Traditional glass tubes in the chest drainage bottle were replaced by aluminium or stainless steel tubes to avoid the hazard and nuisance of frequent breakage of the glass tubes. Oscillations were observed in a column of fluid retained in a loop created in the chest tube. [ABSTRACT FROM AUTHOR]

In order to reduce the inconvenience of cumbersome chest drainage bottles and allow greater mobility to the patient, we describe the use of ordinary urinary drainage bags with unidirectional valve as an alternative method of intercostal drainage. [ABSTRACT FROM AUTHOR]