Computed tomography attenuation in differential diagnosis of transudative and exudative pleural effusions.

OBJECTIVE: Pleural effusion is a common medical problem. It is important to decide whether the pleural fluid is a transudate or an exudate. This study aims to measure the attenuation values of pleural effusions on thorax computed tomography and to investigate the efficacy of this measurement in the diagnostic separation of transudates and exudates. MATERIALS AND METHODS: 380 cases who underwent thoracentesis and thorax computed tomography with pleural effusion were classified as exudates or transudates based on Light's criteria. Attenuation measurements in Hounsfield units were performed through the examination of thorax computed tomography images. RESULTS: 380 patients were enrolled (39 % women), the mean age was 69.9 ± 15.2 years. 125 (33 %) were transudates whereas 255 (67 %) were exudates. The attenuation values of exudates were significantly higher than transudates (15.1 ± 5.1 and 5.0 ± 3.4) (p < 0.001). When the attenuation cut-off was set at ≥ 10 HU, exudates were differentiated from transudates at high efficiency (sensitivity is 89.7 %, specificity is 94.4 %, PPV is 97 %, NPV is 81.9 %). When the cut-off value was accepted as < 6 HU, transudates were differentiated from exudates with 97.2 % specificity. CONCLUSION: The attenuation measurements of pleural fluids can be considered as an efficacious way of differentiating exudative and transudative pleural effusions.

Ultrasound quantification of pleural effusion volume in supine position: comparison of three model formulae.

BACKGROUND: To investigate the accuracy of three model formulae for ultrasound quantification of pleural effusion (PE) volume in patients in supine position. METHODS: A prospective study including 100 patients with thoracentesis and drainage of PE was conducted. Three model formulae (single section model, two section model and multi-section model) were used to calculate the PE volume. The correlation and consistency analyses between calculated volumes derived from three models and actual PE volume were performed. RESULTS: PE volumes calculated by three models all showed significant linear correlations with actual PE volume in supine position (all p < 0.001). The reliability of multi-section model in predicting PE volume was significantly higher than that of single section model and slightly higher than that of two section model. When compared with actual drainage volume, the intra-class correlation coefficients (ICCs) of single section model, two section model and multi-section model were 0.72, 0.97 and 0.99, respectively. Significant consistency between calculated PE volumes by using two section model and multi-section model existed for full PE volume range (ICC 0.98). CONCLUSION: Based on the convenience and accuracy of ultrasound quantification of PE volume, two section model is recommended for pleural effusion assessment in routine clinic, though different model formulae can be selected according to clinical needs.

Bilothorax: A Case Report and Systematic Literature Review of the Rare Entity.

Background: Bilothorax is defined as the presence of bile in the pleural space. It is a rare condition, and diagnosis is confirmed with a pleural fluid-to-serum bilirubin ratio of >1. Methods: The PubMed, Embase, Google Scholar, and CINAHL databases were searched using predetermined Boolean parameters. The systematic literature review was done per PRISMA guidelines. Retrospective studies, case series, case reports, and conference abstracts were included. The patients with reported pleural fluid analyses were pooled for fluid parameter data analysis. Results: Of 838 articles identified through the inclusion criteria and removing 105 duplicates, 732 articles were screened with abstracts, and 285 were screened for full article review. After this, 123 studies qualified for further detailed review, and of these, 115 were pooled for data analysis. The mean pleural fluid and serum bilirubin levels were 72 mg/dL and 61 mg/dL, respectively, with a mean pleural fluid-to-serum bilirubin ratio of 3.47. In most cases, the bilothorax was reported as a subacute or remote complication of hepatobiliary surgery or procedure, and traumatic injury to the chest or abdomen was the second most common cause. Tube thoracostomy was the main treatment modality (73.83%), followed by serial thoracentesis. Fifty-two patients (51.30%) had associated bronchopleural fistulas. The mortality was considerable, with 18/115 (15.65%) reported death. Most of the patients with mortality had advanced hepatobiliary cancer and were noted to die of complications not related to bilothorax. Conclusion: Bilothorax should be suspected in patients presenting with pleural effusion following surgical manipulation of hepatobiliary structures or a traumatic injury to the chest. This review is registered with CRD42023438426.

A Multidisciplinary Curriculum to Standardize Chest Procedures Training for Trainees in General Surgery, Emergency Medicine, and Critical Care.

Introduction: Critical care, emergency medicine, and surgical trainees frequently perform surgical and Seldinger-technique tube thoracostomy, thoracentesis, and thoracic ultrasound. However, approaches to teaching these skills are highly heterogeneous. Over 10 years, we have developed a standardized, multidisciplinary curriculum to teach these procedures. Methods: Emergency medicine residents, surgical residents, and critical care fellows, all in the first year of their respective programs, underwent training in surgical and Seldinger chest tube placement and securement, thoracentesis, and thoracic ultrasound. The curriculum included preworkshop instructional videos and 45-minute in-person practice stations (3.5 hours total). Sessions were co-led by faculty from emergency medicine, thoracic surgery, and pulmonary/critical care who performed real-time formative assessment with standardized procedural steps. Postcourse surveys assessed learners' confidence before versus after the workshop in each procedure, learners' evaluations of faculty by station and specialty, and the workshop overall. Results: One hundred twenty-three trainees completed course evaluations, demonstrating stable and positive responses from learners of different backgrounds taught by a multidisciplinary group of instructors, as well as statistically significant improvement in learner confidence in each procedure. Over time, we have made incremental changes to our curriculum based on feedback from instructors and learners. Discussion: We have developed a unique curriculum designed, revised, and taught by a multidisciplinary faculty over many years to teach a unified approach to the performance of common chest procedures to surgical, emergency medicine, and critical care trainees. Our curriculum can be readily adapted to the needs of institutions that desire a standardized, multidisciplinary approach to thoracic procedural education.

Intrapleural nivolumab in cancer patients with pleural effusion.

ABSTRACT: We assessed the preliminary efficacy and toxicity of intrapleural instillation of nivolumab in patients with large pleural effusion. Patients with metastatic cancers who have a large volume of pleural effusion and required evacuation were eligible. Thoracentesis followed by nivolumab (40 mg, single intrapleural instillation) was performed. The primary endpoint was 3-month recurrence-free survival. A total of 13 patients were enrolled. The study was terminated after stage 1 as no efficacy was observed; 7 patients (54%) had a recurrence of pleural effusion at 3 months. Thirteen (100%) patients had no recurrence, dyspnea, or cough within 1 month, and the median time to recurrence was 1.9 months (95% confidence interval [CI], 1.35-2.5). No adverse events were identified. We concluded that a single intrapleural instillation of the nivolumab at 40 mg was ineffective and well-tolerated in cancer patients with pleural effusion.

Exudative pleural effusion during sunitinib treatment.

Drug-induced pleural effusion is one of the rare causes of exudative pleural effusion and a high index of suspicion is necessary to lead to early diagnosis. We hereby present the case of a young male in his late 30s, known case of metastatic gastrointestinal stromal tumour on sunitinib therapy, who presented with right-sided mild pleural effusion. Diagnostic thoracentesis showed the effusion to be a monomorphic exudate with low adenosine deaminase, which was negative for malignant cells on cytopathology. A contrast-enhanced CT chest revealed an enlarged lymph node (LN) at the 4R station, cytological analysis of which was suggestive of reactive lymphoid hyperplasia. Infective workup of the LN aspirate and bronchoalveolar lavage taken from the right middle lobe was negative. After systematically excluding the usual causes of exudative pleural effusion, sunitinib was considered to be a possible cause and was, therefore, withheld. A repeat chest X-ray after 3 weeks of stopping the drug showed resolution of the pleural effusion.

Resident physician training in bedside pleural procedures: A one-year experience at a teaching hospital.

BACKGROUND AND OBJECTIVE: This study aims to quantify bedside pleural procedures performed at a quaternary teaching hospital describing technical and epidemiological aspects. MATERIALS AND METHODS: The authors retrospectively reviewed consecutive patients who underwent invasive thoracic bedside procedures between March 2022 and February 2023. RESULTS: 463 chest tube insertions and 200 thoracenteses were performed during the study period. Most procedures were conducted by 1st-year Thoracic Surgery residents, with Ultrasound Guidance (USG). There was a notable preference for small-bore pigtail catheters, with a low rate of immediate complications. CONCLUSION: Bedside thoracic procedures are commonly performed in current medical practice and are significant in surgical resident training. The utilization of pigtail catheters and point-of-care ultrasonography by surgical residents in pleural procedures is increasingly prevalent and demonstrates high safety.

Re-expansion Pulmonary Edema (REPE) Following Thoracentesis: Is Large-Volume Thoracentesis Associated with Increased Incidence of REPE?

PURPOSE: To determine the safety and efficacy associated with drainage volumes greater than 1,500 mL in a single, unilateral thoracentesis without pleural manometry measurements. MATERIALS AND METHODS: This retrospective, single-institution study included 872 patients (18 years and older) who underwent ultrasound-guided thoracentesis. Patient and procedures data were collected including demographics, number of and laterality of thoracenteses, volume and consistency of fluid removed, and whether clinical or radiologic evidence of re-expansion pulmonary edema (REPE) developed within 24 h of thoracentesis. Fisher's exact test was used to test the significance of the relationship between volume of fluid removed and evidence of REPE. RESULTS: A total of 1376 thoracenteses were performed among the patients included in the study. The mean volume of fluid removed among all procedures was 901.1 mL (SD = 641.7 mL), with 194 (14.1%) procedures involving the removal of ≥ 1,500 mL of fluid. In total, six (0.7%) patients developed signs of REPE following thoracentesis, five of which were a first-time thoracentesis. No statistically significant difference in incidence of REPE was observed between those with ≥ 1,500 mL of fluid removed compared to those with < 1,500 mL of fluid removed (p-value = 0.599). CONCLUSIONS: Large-volume thoracentesis may safely improve patients' symptoms while preventing the need for repeat procedures.

Management of malignant pleural effusion and trapped lung: a survey of respiratory physicians and thoracic surgeons in Australasia.

BACKGROUND: Malignant pleural effusions (MPEs) are common, and a third of them have underlying trapped lung (TL). Management of MPE and TL is suspected to be heterogeneous. Understanding current practices in Australasia is important in guiding policies and future research. AIMS: Electronic survey of Australia-New Zealand respiratory physicians, thoracic surgeons and their respective trainees to determine practice of MPE and TL management. RESULTS: Of the 132 respondents, 56% were respiratory physicians, 23% were surgeons and 20% were trainees. Many respondents defined TL as >25% or any level of incomplete lung expansion; 75% would use large-volume thoracentesis to determine whether TL was present. For patients with TL, indwelling pleural catheters (IPCs) were the preferred treatment irrespective of prognosis. In those without TL, surgical pleurodesis was the most common choice if prognosis was >6 months, whereas IPC was the preferred option if survival was <3 months. Only 5% of respondents considered decortication having a definite role in TL, but 55% would consider it in select cases. Forty-nine per cent of surgeons would not perform decortication when the lung does not fully expand intra-operatively. Perceived advantages of IPCs were minimisation of hospital time, effusion re-intervention and usefulness irrespective of TL status. Perceived disadvantages of IPCs were lack of suitable drainage care, potentially indefinite duration of catheter-in-situ and catheter complications. CONCLUSION: This survey highlights the lack of definition of TL and heterogeneity of MPE management in Australasia, especially for patients with expandable lungs. This survey also identified the main hurdles of IPC use that should be targeted.

Pleural fluid characteristics of patients with COVID-19 infection.

INTRODUCTION: Pleural effusions are known to occur in many cases of COVID-19. Data on typical characteristics of COVID-19-associated pleural effusions are limited. The goal of this project was to characterize the pleural fluid from patients with COVID-19. METHODS: We retrospectively collected electronic medical record data from adults hospitalized at a large metropolitan hospital system with COVID-19 infection who had a pleural effusion and a thoracentesis performed. We assessed pleural fluid characteristics and applied Light's criteria. RESULTS: We identified 128 effusions from 106 unique patients; 45.4% of the effusions had fluid/serum protein ratio greater than 0.5, 33.9% had fluid/serum lactate dehydrogenase (LDH) greater than 0.6, and 56.2% had fluid LDH greater than 2/3 of the serum upper limit of normal. Altogether, 68.5% of effusions met at least one of these three characteristics and therefore were exudative by Light's criteria. The white blood cell (WBC) differential was predominantly lymphocytic (mean 42.8%) or neutrophilic (mean 28.7%); monocytes (mean 12.7%) and eosinophils (mean 2.5%) were less common. CONCLUSION: We demonstrate that 68.5% of pleural effusions in patients with COVID-19 infection were exudative and hypothesize that COVID-19-associated pleural effusions are likely to be exudative with WBC differential more likely to be predominantly lymphocytic.

Thoracentesis techniques: A literature review.

Thoracentesis is performed by 4 methods: gravity, manual aspiration, vacuum-bottle suction, and wall suction. This literature review investigates the safety of these techniques and determines if there is significant difference in complication rates. A comprehensive literature search revealed 6 articles studying thoracentesis techniques and their complication rates, reviewing 20,815 thoracenteses: 80 (0.4%) by gravity, 9431 (45.3%) by manual aspiration, 3498 (16.8%) by vacuum-bottle suction, 7580 (36.4%) by wall suction and 226 (1.1%) unspecified. Of the 6 studies, 2 were smaller with 100 and 140 patients respectively. Overall, there was a 4.4% complication rate including hemothoraces, pneumothoraces, re-expansion pulmonary edema (REPE), chest discomfort, bleeding at the site, pain, and vasovagal episodes. The pneumothorax and REPE rate was 2.5%. Sub-analyzed by each method, there was a 47.5% (38/80) complication rate in the gravity group, 1.2% (115/9431) in the manual aspiration group including 0.7% pneumothorax or REPE, 8% (285/3498) in the vacuum-bottle group including 3.7% pneumothorax or REPE, 4% (309/7580) in the wall suction group all of which were either pneumothorax or REPE, and 73% (166/226) in the unspecified group most of which were vasovagal episodes. Procedure duration was less in the suction groups versus gravity drainage. The 2 smaller studies indicated that in the vacuum groups, early procedure termination rate from respiratory failure was significantly higher than non-vacuum techniques. Significant complication rate from thoracentesis by any technique is low. Suction drainage was noted to have a lower procedure time. Symptom-limited thoracentesis is safe using vacuum or wall suction even with large volumes drained. Other factors such as procedure duration, quantity of fluid removed, number of needle passes, patients' BMI, and operator technique may have more of an impact on complication rate than drainage modality. All suction modalities of drainage seem to be safe. Operator technique, attention to symptom development, amount of fluid removed, and intrapleural pressure changes may be important in predicting complication development, and therefore, may be useful in choosing which technique to employ. Specific drainage modes and their complications need to be further studied.

Diagnostic accuracy of thoracic CT to differentiate transudative from exudative pleural effusion prior to thoracentesis.

BACKGROUND: Computed tomography (CT) scan is commonly performed for pleural effusion diagnostis in the clinic. However, there are limited data assessing the accuracy of thoracic CT for the separation of transudative from exudative effusions. The study aimed to determine the diagnostic value of thoracic CT in distinguishing transudates from exudates in patients with pleural effusion. METHODS: This is a two-center retrospective analysis of patients with pleural effusion, a total of 209 patients were included from The First Affiliated Hospital of Henan University of Science and Technology as the derivation cohort (Luoyang cohort), and 195 patients from the First Affiliated Hospital of Zhengzhou University as the validation cohort (Zhengzhou cohort). Patients who underwent thoracic CT scan followed by diagnostic thoracentesis were enrolled. The optimal cut-points of CT value in pleural fluid (PF) and PF to blood CT value ratio for predicting a transudative vs. exudative pleural effusions were determined in the derivation cohort and further verified in the validation cohort. RESULTS: In the Derivation (Luoyang) cohort, patients with exudates had significantly higher CT value [13.01 (10.01-16.11) vs. 4.89 (2.31-9.83) HU] and PF to blood CT value ratio [0.37 (0.27-0.53) vs. 0.16 (0.07-0.26)] than those with transudates. With a cut-off value of 10.81 HU, the area under the curve (AUC), sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of CT value were 0.85, 88.89%, 68.90%, 43.96%, and 95.76%, respectively. The optimum cut-value for PF to blood CT value ratio was 0.27 with AUC of 0.86, yielding a sensitivity of 61.11%, specificity of 86.36%, PPV of 78.57%, and NPV of 73.08%. These were further verified in the Validation (Zhengzhou) cohort. CONCLUSIONS: CT value and PF to blood CT value ratio showed good differential abilities in predicting transudates from exudates, which may help to avoid unnecessary thoracentesis.

Thoracentesis to alleviate pleural effusion in acute heart failure: study protocol for the multicentre, open-label, randomised controlled TAP-IT trial.

INTRODUCTION: Pleural effusion is present in half of the patients hospitalised with acute heart failure. The condition is treated with diuretics and/or therapeutic thoracentesis for larger effusions. No evidence from randomised trials or guidelines supports thoracentesis to alleviate pleural effusion due to acute heart failure. The Thoracentesis to Alleviate cardiac Pleural effusion Interventional Trial (TAP-IT) will investigate if a strategy of referring patients with acute heart failure and pleural effusion to up-front thoracentesis by pleural pigtail catheter insertion in addition to pharmacological therapy compared with pharmacological therapy alone can increase the number of days the participants are alive and not hospitalised during the 90 days following randomisation. METHODS AND ANALYSIS: TAP-IT is a pragmatic, multicentre, open-label, randomised controlled trial aiming to include 126 adult patients with left ventricular ejection fraction ≤45% and a non-negligible pleural effusion due to heart failure. Participants will be randomised 1:1, stratified according to site and anticoagulant treatment, and assigned to referral to up-front ultrasound-guided pleural pigtail catheter thoracentesis in addition to standard pharmacological therapy or to standard pharmacological therapy only. Thoracentesis is performed according to local guidelines and can be performed in participants in the pharmacological treatment arm if their condition deteriorates or if no significant improvement is observed within 5 days. The primary endpoint is how many days participants are alive and not hospitalised within 90 days from randomisation and will be analysed in the intention-to-treat population. Key secondary outcomes include 90-day mortality, complications, readmissions, and quality of life. ETHICS AND DISSEMINATION: The study has been approved by the Capital Region of Denmark Scientific Ethical Committee (H-20060817) and Knowledge Center for Data Reviews (P-2021-149). All participants will sign an informed consent form. Enrolment began in August 2021. Regardless of the nature, results will be published in a peer-reviewed medical journal. TRIAL REGISTRATION NUMBER: NCT05017753.

Teaching and Assessing Bedside Procedures: A Standardized Cross-Disciplinary Framework for Graduate Medical Education.

ABSTRACT: Performing bedside procedures requires knowledge, reasoning, physical adeptness, and self-confidence; however, no consensus on a specific, comprehensive strategy for bedside procedure training and implementation is available. Bedside procedure training and credentialing processes across large institutions may vary among departments and specialties, leading to variable standards, creating an environment that lacks consistent accountability, and making quality improvement difficult. In this Scholarly Perspective, the authors describe a standardized bedside procedure training and certification process for graduate medical education with a common, institution-wide educational framework for teaching and assessing the following 7 important bedside procedures: paracentesis; thoracentesis; central venous catheterization; arterial catheterization; bladder catheterization or Foley catheterization; lumbar puncture; and nasogastric, orogastric, and nasoenteric tube placement. The proposed framework is a 4-stage process that includes 1 preparatory learning stage with simulation practice for knowledge acquisition and 3 clinical stages to guide learners from low-risk to high-risk practice and from high to low supervision. The pilot rollout took place at Henry Ford Hospital from December 2020 to July 2021 for 165 residents in the emergency medicine and/or internal medicine residency programs. The program was fully implemented institution-wide in July 2021. Assessment strategies encompass critical action checklists to confirm procedural understanding and a global rating scale to measure performance quality. A major aim of the bedside procedure training and certification was to standardize assessments so that physician trainers from multiple specialties could train, assess, and supervise any participating trainee, regardless of discipline. The authors list considerations revealed from the pilot rollout regarding electronic tracking systems and several benefits and implementation challenges to establishing institution-wide standards. The proposed framework was assembled by a multidisciplinary physician task force and will assist other institutions in adopting best approaches for training physicians in performing these critically important and difficult-to-perform procedures.

Safety and Outcomes of Outpatient Pleural Drainage in Symptomatic Postoperative Cardiac Surgery Patients.

BACKGROUND: Symptomatic pleural effusions and anticoagulant/antiplatelet medication use in postoperative cardiac surgery are common. Guidelines and recommendations are currently mixed regarding medication management related to invasive procedure performance. We aimed to describe the outcomes of postoperative cardiac surgery patients referred for outpatient, symptomatic pleural effusion management. METHODS: A retrospective study of post-cardiac surgery patients undergoing outpatient thoracentesis from 2016 to 2021 was performed. Demographics, operative details, pleural disease characteristics, outcomes, and complications were collected. Odds ratios with confidence intervals were estimated and adjusted by multivariate logistic regression to investigate the association with multiple thoracenteses. RESULTS: A total of 110 patients underwent 332 thoracenteses. The median age was 68 years and most common operation was coronary artery bypass. Anticoagulation or antiplatelet use was identified in 97%. Thirteen complications were identified, with all major complications (n=3) related to bleeding. The amount of fluid present at the time of initial thoracentesis (>1500 milliliters) was associated with increased odds ratio of subsequent multiple thoracentesis (Unadjusted odds ratio, 6.75 (CI - 1.43 to 31.9). No other variables had a significant association with the need for multiple procedures. CONCLUSION: Within a postoperative cardiac surgery population presenting with symptomatic pleural disease, we observed that thoracentesis performed on antiplatelet and/or anticoagulant medication is relatively safe. We also identified that many patients can be managed as outpatients and that most pleural effusions remain self-limited. The presence of larger amounts of pleural fluid at initial thoracentesis may be associated with increased odds for additional drainage.

Idiopathic Lymphocytic Pleuritis Responding to Corticosteroid Therapy.

An 83-year-old man presented with chronic dyspnea, and chest X-ray showed bilateral pleural effusion. Right thoracentesis revealed lymphocyte-predominant exudate with no malignancy; bacterial and mycobacterial cultures were negative. Thoracoscopy via the right chest and a biopsy of the same site were performed; these showed lymphoplasmacytic infiltration and fibrosis, ruling out malignancy or tuberculosis. We decided to start corticosteroid therapy for the diagnosis of idiopathic lymphocytic pleuritis (ILP). The patient was discharged after clinical improvement, and steroids were tapered off. An early diagnosis by thoracoscopy and the exclusion of other diseases are important for initiating steroid therapy in patients with ILP.

Safety and Risk Factors of Needle Thoracentesis Decompression in Tension Pneumothorax in Patients over 75 Years Old.

Background: There are very few professional recommendations or guidelines on the needle thoracentesis decompression (NTD) for the tension pneumothorax in the elderly. This study aimed to investigate the safety and risk factors of tension pneumothorax NTD in patients over 75 years old based on CT evaluation of the chest wall thickness (CWT). Methods: The retrospective study was conducted among 136 in-patients over 75 years old. The CWT and closest depth to vital structure of the second intercostal space at the midclavicular line (second ICS-MCL) and the fifth intercostal space at the midaxillary line (fifth ICS-MAL) were compared as well as the expected failure rates and the incidence of severe complications of different needles. We also analyzed the influence of age, sex, presence or absence of chronic obstructive pulmonary disease (COPD), and body mass index (BMI) on CWT. Results: The CWT of the second ICS-MCL was smaller than the fifth ICS-MAL both on the left and the right side (P < 0.05). The success rate associated with a 7 cm needle was significantly higher than a 5 cm needle (P < 0.05), and the incidence of severe complications with a 7 cm needle was significantly less than an 8 cm needle (P < 0.05). The CWT of the second ICS-MCL was significantly correlated with age, sex, presence or absence of COPD, and BMI (P < 0.05), whereas the CWT of the fifth ICS-MAL was significantly correlated with sex and BMI (P < 0.05). Conclusion: The second ICS-MCL was recommended as the primary thoracentesis site and a 7 cm needle was advised as preferred needle length for the older patients. Factors such as age, sex, presence or absence of COPD, and BMI should be considered when choosing the appropriate needle length.

Pleural effusion and thoracentesis in ICU patients: A longitudinal observational cross-sectional study.

BACKGROUND: Pleural effusion is common among patients in the intensive care unit (ICU) but reported prevalence varies. Thoracentesis may improve respiratory status, however, indications for this are unclear. We aimed to explore prevalence, development, and progression of pleural effusion, and the incidence and effects of thoracentesis in adult ICU patients. METHODS: This is a prospective observational study utilizing repeated daily ultrasonographic assessments of pleurae bilaterally, conducted in all adult patients admitted to the four ICUs of a Danish university hospital throughout a 14-day period. The primary outcome was the proportion of patients with ultrasonographically significant pleural effusion (separation between parietal and visceral pleurae >20 mm) in either pleural cavity on any ICU day. Secondary outcomes included the proportion of patients with ultrasonographically significant pleural effusion receiving thoracentesis in ICU, and the progression of pleural effusion without drainage, among others. The protocol was published before study initiation. RESULTS: In total, 81 patients were included of which 25 (31%) had or developed ultrasonographically significant pleural effusion. Thoracentesis was performed in 10 of these 25 patients (40%). Patients with ultrasonographically significant pleural effusion, which was not drained, had an overall decrease in estimated pleural effusion volume on subsequent days. CONCLUSION: Pleural effusion was common in the ICU, but less than half of all patients with ultrasonographically significant pleural effusion underwent thoracentesis. Progression of pleural effusion without thoracentesis showed reduced volumes on subsequent days.

A practical approach to pseudoexudative pleural effusions.

Light's criteria falsely label a significant number of effusions as exudates. Such exudative effusions with transudative etiologies are referred to as "pseduoexudates". In this review, we discuss a practical approach to correctly classify an effusion that may be a pseudoexudate. A PubMed search yielded 1996 manuscripts between 1990 and 2022. Abstracts were screened and 29 relevant studies were included in this review article. Common etiologies for pseudoexudates include diuretic therapy, traumatic pleural taps, and coronary artery bypass grafting. Here, we explore alternative diagnostic criteria. Concordant exudates (CE), defined as effusions where proteins in pleural fluid/serum (PF/SPr) > 0.5 and pleural fluid LDH level of >160 IU/L (>2/3 upper limit of normal) confer higher predictive value to the Light's criteria. Serum-pleural effusion albumin gradient (SPAG) > 1.2 g/dL and serum-pleural effusion protein gradient (SPPG) > 3.1 g/dL together yielded a sensitivity of 100% in heart failure and a sensitivity of 99% in hepatic hydrothorax whe n identifying pseudoexudates (Bielsa et al., 2012) [5]. Pleural fluid N-Terminal Pro Brain Natriuretic Peptide (NTPBNP) offered a specificity and sensitivity of 99% in identifying pseudoexudates when using a cut-off of >1714 pg/mL (Han et al., 2008) [24]. However, its utility remains questionable. Additionally, we also looked at pleural fluid cholesterol and imaging modalities such as ultrasound and CT scan to measure pleural thickness and nodularity. Finally, the diagnostic algorithm we suggest involves using SPAG >1.2 g/dL and SPPG >3.1 g/dL in effusions classified as exudates when there is a strong clinical suspicion for pseudoexudates.

Efficacy and safety of early chest tube removal after selective pulmonary resection with high-output drainage: A systematic review and meta-analysis.

BACKGROUND: There is controversy over the drainage threshold for removal of chest tubes in the absence of significant air leakage after selective pulmonary resection. METHODS: A comprehensive search of online databases (PubMed, Web of Science, Embase, Cochrane Library, Scopus, Ovid, Elsevier, Ebsco, and Wiley) and clinical trial registries (WHO-ICTRP and ClinicalTrials.gov) was performed to investigate the efficacy and safety of early chest tube removal with high-output drainage. Primary outcome (postoperative hospital day) and secondary outcomes (30-day complications, rate of thoracentesis, and chest tube placement) were extracted and synthesized. Subgroup analysis, meta-regression, and sensitivity analysis were used to explore the potential heterogeneity. Study quality was assessed with the Newcastle-Ottawa Scale, and evidence was graded using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) assessment by the online GRADEpro Guideline Development Tool. RESULTS: Six cohort studies with a total of 1262 patients were included in the final analysis. The postoperative hospital stay in the high-output group was significantly shorter than in the conventional treatment group (weighted mean difference: -1.34 [-2.34 to -0.34] day, P = .009). While there was no significant difference between 2 groups in 30-day complications (relative ratio [RR]: 0.92 [0.77-1.11], P = .38), the rate of thoracentesis (RR: 1.93 [0.63-5.88], P = .25) and the rate of chest tube placement (RR: 1.00 [0.37-2.70], P = .99). According to the sensitivity analysis, the relative impacts of the 2 groups had already stabilized. Subgroup analysis revealed that postoperative hospital stay was modified by Newcastle-Ottawa Scale score. The online GRADEpro Guideline Development Tool presented very low quality of evidence for the available data. CONCLUSIONS: This meta-analysis revealed that it is feasible and safe to remove a chest tube with high-output drainage after pulmonary resection for selected patients.