Large-volume Thoracentesis Research Articles

Gravity- vs Wall Suction-Driven Large-Volume Thoracentesis: A Randomized Controlled Study

Prior studies have found no differences in procedural chest discomfort for patients undergoing manual syringe aspiration or drainage with gravity after thoracentesis. However, whether gravity drainage could protect against chest pain due to the larger negative-pressure gradient generated by wall suction has not been investigated. Does wall suction drainage result in more chest discomfort compared with gravity drainage in patients undergoing large-volume thoracentesis? In this multicenter, single-blinded, randomized controlled trial, patients with large free-flowing effusions of≥ 500mL were assigned at a 1:1 ratio to wall suction or gravity drainage. Wall suction was performed with a suction system attached to the suction tubing and with vacuum pressure adjusted to full vacuum. Gravity drainage was performed with a drainage bag placed 100cm below the catheter insertion site and connected via straight tubing. Patients rated chest discomfort on a 100-mm visual analog scale before, during, and after drainage. The primary outcome was postprocedural chest discomfort at 5 min. Secondary outcomes included measures of postprocedure chest discomfort, breathlessness, procedure time, volume of fluid drained, and complication rates. Of the 228 patients initially randomized, 221 were included in the final analysis. The primary outcome of procedural chest discomfort did not differ significantly between the groups (P= .08), nor did the secondary outcomes of postprocedural discomfort and dyspnea. Similar volumes were drained in both groups, but the procedure duration was longer in the gravity arm by approximately 3 min. No differences in rate of pneumothorax or reexpansion pulmonary edema were noted between the two groups. Thoracentesis via wall suction and gravity drainage results in similar levels of procedural discomfort and dyspnea improvement. ClinicalTrials.gov; No.: NCT05131945; URL: www. gov.

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

To determine the safety and efficacy associated with drainage volumes greater than 1,500mL in a single, unilateral thoracentesis without pleural manometry measurements. This retrospective, single-institution study included 872 patients (18years 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 24h of thoracentesis. Fisher's exact test was used to test the significance of the relationship between volume of fluid removed and evidence of REPE. A total of 1376 thoracenteses were performed among the patients included in the study. The mean volume of fluid removed among all procedures was 901.1mL (SD = 641.7mL), with 194 (14.1%) procedures involving the removal of ≥ 1,500mL 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 ≥ 1,500mL of fluid removed compared to those with < 1,500mL of fluid removed (p-value = 0.599). 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.

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. Electronic survey of Australia-New Zealand respiratory physicians, thoracic surgeons and their respective trainees to determine practice of MPE and TL management. 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. 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.

FREQUENCY OF PNEUMOTHORAX AMONG PATIENTS PRESENTED WITH LARGE VOLUME THORACENTESIS

This study aimed to determine the frequency of pneumothorax among patients who underwent large-volume thoracentesis. A cross-sectional study was conducted at the Department of Pulmonology, Pak Red Crescent Medical College &amp; Teaching Hospital, Lahore, from January 2023 to June 2023. The study included 110 patients, aged between 50 and 75 years, of both genders, who presented with a large volume of thoracentesis. The frequency of pneumothorax was determined. The mean age of the patients was 62.04±7.04 years, with male patients accounting for 62.7% and female patients accounting for 37.3%. The frequency of pneumothorax was found to be 13.6%. No significant statistical association was observed between pneumothorax and gender. The study found that the frequency of pneumothorax among patients who underwent large-volume thoracentesis was 13.6%.

C11 LARGE PLEURAL AND PERICARDIAL EFFUSION: WHICH DRAIN FIRST?

Abstract Introduction Large pleural and pericardial effusion is a common finding in lung cancer patients. However, a chronic large pleural effusion and the “lung entrapment” fenomenon, due to the neoplastic lung infiltration, could precipitate the re–expansion pulmonary edema (REPO) after the thoracentesis procedure. REPO is a rare and potentially life–threatening complication after large volume thoracentesis. It is characterized by alveolar infiltration in the reexpanded lung.Indeed, in the presence of “lung entrapment”, REPO development could be due not only to and excessive fluid removal, but also to the development of an excessively negative intrapleural pressure (&amp;lt; – 20 mmHg). As the REPO is often associated to an hemodynamic impairment, in patients with concomitant severe pericardial effusion, this condition could cause cardiac tamponade and the optimal therapeutic approach could be challenging.In this perspective, the decision on the effusion to be drained first, in this population, is not always straightforward.Case report In a 62 years –old woman with severe respiratory failure, a chest CT scan showed a massive left –sided pleural effusion with a complete collapse of the left lung, a severe pericardial effusion (35 mm) and the presence of malignant mediastinal nodes. (Figure 1).In the ICU a left thoracentesis was performed, with an early drainage of 1400 ml, the drain was then clamped. 30 minutes later, the patient developed a severe acute respiratory failure. An urgent chest x ray revealed an ipsilateral pulmonary oedema (Figure2). The patient was then treated with respiratory support with cPAP and intravenous diuretic therapy. Afterward, a rapid hemodynamic derangement occurred, with cardiac tamponade. An emergency echoguided pericardiocentesis was then performed followed by an immediate recovery. A repeated thorax CT scan revealed an advanced pulmonary tumor (Figure 3). Discussion In this case all the risk factors for REPO were coexistent: chronic pleural effusion and lung cancer. In addition, the large pericardial effusion represented a complicating factor in this situation as both the cPAP and the REPO’s hypovolemia may have brought to a clinical tamponade. In this context, where a neoplastic severe pleural and pericardial effusions are coexistent, it is essential to know which possible complications may occur after a large volume thoracentesis in order to prevent a high risk urgent pericardial drainage in patient with severe respiratory distress.

Abstract No. 570 Incidence of expansion pulmonary edema following large-volume thoracentesis: does volume of fluid removed correlate with risk?

Current guidelines and recommendations prefer the removal of no more than 1,500 mL per lung during a single thoracentesis to reduce the risk of re-expansion of pulmonary edema (RPE)1. However, total drainage of a pleural effusion can markedly improve patient symptoms and reduce the need for future procedures. This retrospective study aimed to determine the safety and efficacy associated with the drainage volumes greater than 1,500 mL in a single, unilateral thoracentesis without pleural manometry measurements.

Improve the clinical research and standardize the management of pleural diseases

Based on the clinical evidence obtained during the past decade, we reviewed herein the evidences in the treatment of 5 types of common pleural diseases. (1) Therapeutic pleural interventions are not recommended for patients with malignant pleural effusion (MPE) who are asymptomatic. In patients with symptomatic MPE, large-volume thoracentesis should be performed in MPE patients to figure out if the patient's symptoms are related to the effusion and/or if the lung is expandable; if so, indwelling pleural catheters and/or talc pleurodesis can be used as first-line definitive intervention. Indwelling pleural catheters, but not pleurodesis should be used in those with symptomatic MPE with nonexpandable lung, failed pleurodesis, or loculated effusion. (2) Randomized controlled trials concerning tuberculous pleurisy management are always scarce. Based on the data from pulmonary tuberculosis trials, it can be accepted that anti-tuberculosis treatment regimen for tuberculous pleurisy with isoniazid, rifampin, and pyrazinamide for two months followed by four months of two drugs, isoniazid and rifampin. (3) A combination of tissue plasminogen activator and deoxyribonuclease can be instilled intrapleurally as the initial treatment, or as a follow-up treatment after surgery for pleural infection. The recommended dosages are as follows: tissue plasminogen activator 10 mg, twice a day, deoxyribonuclease 5 mg, twice a day. (4) The randomized controlled trial has provided evidence that conservative management is an acceptable alternative to interventional management for moderate-to-large primary spontaneous pneumothorax. (5) For patients with malignant pleural mesothelioma, nivolumab plus ipilimumab is capable of significantly improving the overall survival of patients versus platinum plus pemetrexed chemotherapy, supporting the use of this regimen as the first-line treatment for these patients, regardless of histological subtype.

DEATH BY CHYLOTHORAX

TOPIC: Disorders of the Pleura TYPE: Fellow Case Reports INTRODUCTION: Chylothorax is a rare entity that is typically associated with significant morbidity and mortality. A majority of cases of chylothorax are secondary to trauma; however, a significant number of chylous effusions are due to non-traumatic causes. This case report describes a recurrent, non-surgical chylous pleural effusion in an elderly male from presumed minimal neck trauma. CASE PRESENTATION: An elderly Caucasian male with a history significant for chronic HErEF, coronary artery disease, and cirrhosis secondary to amiodarone use who presented with progressive dyspnea on exertion after sustaining blunt injury to his R shoulder. Initial chest film demonstrated a large right sided pleural effusion, which was new compared to a prior chest film obtained two weeks earlier. Pulmonary medicine was consulted to perform right sided thoracentesis. 3 liters of chylous fluid was removed. Chemistry findings of the pleural fluid were transudative based on Light's criteria; however, pleural triglyceride level was elevated at 283 mg/dL with a pleural cholesterol level less than 50 mg/dL. Flow cytometry obtained on the pleural fluid was negative for malignant cells. A bedside ultrasound was completed at the time of initial thoracentesis, which did not demonstrate any abdominal ascites. A CT chest/abdomen was obtained, which was negative for evidence of malignancy. Patient developed worsening dyspnea, which prompted repeat thoracentesis two days following his initial thoracentesis with pleural studies again consistent with chylothorax. Patient was then referred for lymphangiography to assess the thoracic duct; however, access was unsuccessful despite two attempts. The chylous effusion reaccumulated every 48 hours and required repeat large volume thoracentesis. Patient developed progressive renal failure and was ultimately transitioned to hospice care. DISCUSSION: It is thought that approximately 50% of chylothorax cases are secondary to trauma. Non-traumatic causes of chylothorax comprise about 40% cases with a majority being secondary to lymphoproliferative malignancies. Transdiaphragmatic fluid migration of chylous ascites and thoracic duct obstruction from increased portal venous pressure have also been seen in patients with underlying cirrhosis. Lymphangiography remains the gold standard for visualization of the thoracic duct; however, this is a protracted procedure with an approximate 80% success rate. There are currently no evidence based guidelines for the evaluation or management of a chylothorax. CONCLUSIONS: This case report reaffirms the notion that chylothorax continues to have a significant morbidity and mortality despite aggressive clinical evaluation. It also demonstrates that minimal trauma can potential result in a thoracic duct injury leading to recurrent chylothorax. It also highlights that there are no current evidence-based guidelines for the evaluation and management of a chylothorax. REFERENCE #1: Riley LE, Ataya A. Clinical approach and review of causes of a chylothorax. Respiratory Medicine. 2019;157:7-13. doi:10.1016/j.rmed.2019.08.014 REFERENCE #2: Guermazi A, Brice P, Hennequin C, Sarfati E. Lymphography: An Old Technique Retains Its Usefulness. RadioGraphics. 2003;23(6):1541-1558. doi:10.1148/rg.236035704 REFERENCE #3: Alejandre-Lafont E, Krompiec C, Rau WS, Krombach GA. Effectiveness of therapeutic lymphography on lymphatic leakage. Acta Radiol. 2011;52(3):305-311. doi:10.1258/ar.2010.090356 DISCLOSURES: No relevant relationships by Jared Dyer, source=Web Response no disclosure submitted for Rebecca Potfay

Hemithorax Opacification &amp; Large Volume Thoracentesis: A Novel Predictor of Re-Expansion Pulmonary Edema

Symptomatic pleural effusions are a common reason for hospital visits. Guidelines recommend draining < 1.5 L with large-volume thoracentesis (LVT) to avoid re-expansion pulmonary edema (REPE). Hemithorax opacification by pleural fluid on chest X-ray (CXR) has not been studied as predictor of REPE. We evaluated the incidence of REPE using hemithorax opacification on CXR.

Efficacy of Initial Large-Volume Thoracentesis for Malignant Pleural Effusions

Large malignant pleural effusions (MPE) are common and can cause respiratory distress. Large-volume thoracentesis (LVT) is the most readily available initial procedure, but its efficacy for large MPE with acute respiratory symptoms is unknown.

A pictorial review of lung torsion using 3D CT cinematic rendering.

Lung torsion is the abnormal rotation of a lobe or lung around its bronchovascular pedicle. It most commonly occurs in the setting of pulmonary resection, though it has also been described after large-volume thoracentesis and video-assisted thoracic surgery, as well as spontaneously. Resulting ischemia can lead to infarction, making this an emergent diagnosis. As findings are often nonspecific, a high index of suspicion is required, especially in the postsurgical setting. 2D CT angiography findings are subtle and include direct signs of pedicle rotation on CT as well as indirect findings including loss of normal parenchymal enhancement, atelectasis of torsed lobe/lung, and abnormal fissure position. These direct and indirect findings are often appreciated on different window presets and upon review of images in multiple planes, with need to collate the information subsequently. 3D cinematic rendering (CR) using multi-planar light sources can readily highlight spatial relationships of vasculature in the chest and may be able to assist in the confident diagnosis of this sometimes subtle but life-threatening pathology. We have provided the first characterization of common lung torsion findings on 3D CR.

AMBULATORY PLEURODESIS: SUCCESSFUL USE OF TALC WITH INDWELLING PLEURAL CATHETER FOR MANAGEMENT OF BILATERAL MALIGNANT PLEURAL EFFUSIONS

SESSION TITLE: Wednesday Fellows Case Report Posters SESSION TYPE: Fellow Case Report Posters PRESENTED ON: 10/23/2019 09:45 AM - 10:45 AM INTRODUCTION: Malignant pleural effusions affect more than 750,000 patients each year in Europe and the United States and account for greater than 125,000 hospitalizations and have an estimated cost of $5 billion per year1,2. Treatment for malignant pleural effusions with expandable lung would favor treatment with talc pleurodesis and often requires days of inpatient hospitalization for management and observation3. Placement of indwelling pleural catheters (IPCs) can be used as successful alternative for management of symptoms in an ambulatory setting3,4. Additionally, administration of talc through an IPC shows increased probability of pleurodesis4. We present a patient with bilateral malignant pleural effusions with successful bilateral pleurodesis using talc instilled through bilateral IPCs. CASE PRESENTATION: A 72-year-old man with a past medical history significant for metastatic melanoma presented to the ED with complaints of progressive dyspnea at rest. Imaging revealed large bilateral pleural effusions with symptomatic improvement with therapeutic thoracentesis. Initial studies were consistent with exudative effusion with negative cytology and patient was discharged with follow-up in Pulmonary Clinic. He underwent repeat large-volume thoracentesis with repeat cytology showing metastatic melanoma. Given rapidly re-accumulating fluid and symptoms, a left IPC was placed with significant improvement and a right IPC was placed 2 weeks later with continued improvement and decreased effusions on repeat U/S. At this time, further management with talc pleurodesis was discussed to ideally eliminate the need of IPCs and enhance the patient’s quality of life. Talc was instilled per IPC plus protocol4 with subsequent ultrasound monitoring with <25 cc of output daily. Given good apposition, the left IPC was removed and 2 weeks later, talc was administered to the right IPC with similar results on ultrasound with upcoming removal of right IPC given continued good apposition and decreased drainage. DISCUSSION: We demonstrate a validated alternative treatment strategy in a patient with bilateral malignant pleural effusions. This presents a plausible alternative to patients to decrease hospital days and expenses, while improving quality of life and allowing for pleurodesis in an outpatient setting. We show success using bilateral IPCs with sequential talc pleurodesis and removal of IPCs. No hospitalizations were made during this time period and the patient tolerated all procedures well. CONCLUSIONS: Given continued advancement in techniques, we continue to show patient-centered care in a challenging population with an outpatient centered treatment approach and use of U/S imaging for clinical management. Reference #1: 1. Marel M, Zrustova M, et al. The incidence of pleural effusion in a well-defined region: epidemiology study in Central Bohemia. Chest 1993; 104:1486-9. Reference #2: 2. Taghizadeh N, Fortin M, Tremblay A. US hospitalizations for malignant pleural effusions: data from the 2012 National Inpatient Sample. Chest 2017;151:845–854. Reference #3: 3. Feller-Kopman D, Reddy C, et al. Management of Malignant Pleural Effusions. An Official ATS/STS/STR Clinical Practice Guidelines. Am J Respir Crit Care Med. 2018 Oct 1; 198(7):839-849. 4. Bhatnagar R, Keenan E, et al. Outpatient Talc Administration by Indwelling Pleural Catheter for Malignant Effusion. N Engl J Med. 2018 Apr 5;378(14):1313-1322. DISCLOSURES: No relevant relationships by Michael Gonzales, source=Web Response No relevant relationships by Tyson Sjulin, source=Web Response No relevant relationships by John Untisz, source=Web Response

Pre-EDIT: A Randomized Feasibility Trial of Elastance-Directed Intrapleural Catheter or Talc Pleurodesis in Malignant Pleural Effusion

Talc slurry pleurodesis (TSP) prevents recurrence of symptomatic malignant pleural effusion (MPE) in 71%to 78%patients. Nonexpansile lung (NEL) frequently accounts for TSP failure but is often occult predrainage, impairing selection of patients. NEL is associated with high pleural elastance (PEL), but technical limitations have hampered the development of PEL as a predictive NEL marker. We performed a single-center, randomized, controlled, open-label feasibility trial of EDIT (elastance-directed indwelling pleural catheter or TSP) management, using a novel digital manometer and a new definition of high PEL. Patients with symptomatic MPE were randomized 1:1 between EDIT and standard care (TSP). EDIT involved PEL assessment during large-volume thoracentesis; patients with high PEL (maximum PEL sustained over 250mL [MaxPEL250]≥ 14.5cm H2O/L) were allocated to immediately receive an indwelling pleural catheter; the remainder underwent immediate drain placement for TSP. The primary outcome measure was recruitment feasibility, defined a priori as 30 patients over 12months. Secondary outcomes included safety, technical reliability, and the aspiration volume required to detect high PEL. The accuracy of the PEL definition for NEL was analyzed post hoc. Thirty-one patients were randomized (one allocation failure) over 12months. PEL assessment (mean duration, 33 minutes) was successful in 13 of 15 patients (87%). No directly attributable serious adverse events occurred. High PEL was detected in seven of 13 patients (54%), associated with 100%sensitivity and 67%specificity for NEL, and was first detected at a median volume of 325mL (range, 250-800mL). A phase 3 trial testing the effect of EDIT management on symptomatic MPE recurrence following TSP is feasible. ClinicalTrials.gov; No.: NCT03319186; URL: www.clinicaltrials.gov.

Routine monitoring with pleural manometry during therapeutic large-volume thoracentesis to prevent pleural-pressure-related complications: a multicentre, single-blind randomised controlled trial

In patients with non-expandable lung, removal of pleural fluid can result in excessively negative pleural pressure, which is associated with chest discomfort, pneumothorax, and re-expansion pulmonary oedema. Pleural manometry is widely used to safeguard against pressure-related complications during thoracentesis despite little evidence to support the approach. We investigated whether monitoring of pleural pressure with manometry during thoracentesis could protect against complications compared with assessment of symptoms alone. We did a prospective randomised single-blind trial involving patients with large pleural effusions at two academic medical centres in, Nashville, TN, and Baltimore, MD, USA. Eligible patients were adults with free-flowing effusions estimated to be at least 0·5 L who could remain seated throughout the procedure. Patients were randomly assigned 1:1 to receive thoracentesis guided by symptoms only (control) or by symptoms plus manometry at timepoints based on volume drained. The randomisation schedule was computer generated, used permuted blocks of four and six, and was stratified by participating institution. Patients, who were masked to study-group assignment, were asked to rate chest discomfort on 100 mm visual analogue scales before, during, and after drainage. In both groups drainage was discontinued before complete evacuation of pleural fluid if patients developed persistent chest discomfort, intractable cough, or other complications. In the manometry group, an additional criterion for stopping was if end-expiratory pleural pressure was lower than -20 cm H2O or declined by more than 10 cm H2O between two measurements to a value less than or equal to -10 cm H2O. The primary outcome was overall chest discomfort from before the start to after the procedure measured by patients 5 min after the end of drainage. Analysis was by modified intention to treat (ie, included all patients with any procedure or outcome data). This trial is registered with ClinicalTrials.gov, number NCT02677883. Between March 4, 2016, and Sept 8, 2017, 191 patients were screened, of whom 128 were randomly assigned treatment and 124 were included in the final analysis (62 in each group). Four patients were excluded because of manometer malfunction (n=2), inability to access effusion due to pleural tumour burden (n=1), and inability to remain seated (n=1). Groups did not differ for the primary outcome (mean difference in chest discomfort score 2·4 mm, 95% CI -5·7 to 10·5, p=0·56). Six (10%) of 62 patients in the control group had asymptomatic pneumothorax ex vacuo compared with none in the manometry group (p=0·01). No serious complications occurred in either group. Measurement of pleural pressure by manometry during large-volume thoracentesis does not alter procedure-related chest discomfort. Our findings do not support the routine use of this approach. Centurion Medical Products.

Clinical Utility of Routine Pleural Manometry During Large Volume Thoracentesis: A Multicenter Randomized Trial

Background: In patients with non-expandable lung, pleural fluid removal can result in excessively negative pleural pressure, associated with chest discomfort, pneumothorax, and reexpansion pulmonary edema. Monitoring pleural pressure during thoracentesis may reduce discomfort and protect against complications. Methods: In this prospective randomized single-blind trial, subjects with large pleural effusions at two academic medical centers were randomly assigned (1:1 ratio) to symptom-guided (control) versus symptom-plus-manometry-guided (manometry) thoracentesis. All had free-flowing effusions meeting pre-specified criteria suggesting volume of at least 500 milliliters. Subjects, who were blinded to assignment, rated chest discomfort on visual analog scales before, during, and after drainage. Pleural pressure was measured at regular intervals in the manometry group. Drainage was discontinued before complete evacuation for persistent chest discomfort, incessant cough, complication, rapidly falling pleural pressure, or end-expiratory pleural pressure lower than -20 cm H2O (latter two only in the manometry group). We performed a modified intention-to-treat analysis. The primary outcome was overall procedural chest discomfort through 5 minutes post-procedure. Findings: Between March 4, 2016 and September 8, 2017, 191 patients were screened. One hundred twenty-eight eligible subjects were randomized with four excluded from the final analysis of 62 subjects per group due to manometer malfunction (n=2), inability to access effusion due to pleural tumor burden (n=1), and inability to remain seated (n=1). There was no difference in the primary outcome of overall procedural chest discomfort between groups (mean difference 2.4, 95% CI -5.7-10.5; p = 0.78). Six asymptomatic pneumothoraces ex-vacuo occurred in the control group; no serious complications occurred in either group. Interpretation: Measurement of pleural pressure during large-volume thoracentesis does not alter procedure-related chest discomfort. This is the first study to directly assess the impact of pleural manometry on important patient-centered clinical outcomes during thoracentesis, and does not support its routine use. This trial was registered at clinicaltrials.gov, NCT02677883 Funding: Centurion Medical Products Declaration of Interest: No authors report any financial or non-financial conflicts of interest pertinent to this work outside the declared funding source for this trial (see below re: role of funding source). Ethics Approval Statement: This randomized single-blind trial recruited inpatient and outpatient subjects at two academic medical centers (Vanderbilt University Medical Center, Nashville, TN, USA and Johns Hopkins Hospital, Baltimore, MD, USA). Institutional Review Boards of both institutions approved this trial (VUMC IRB number 151492; JHU IRB number 00119664).

Abstract No. 564 Optimal pleural fluid volume for diagnosing malignancy: the more the better?

The purpose is to determine the optimal pleural fluid volume needed to diagnose malignancy using pleural fluid cytology. Median survival rates after malignant pleural effusion (MPE) diagnosis are approximately 4-6 months, highlighting the importance of early diagnosis to guide therapy. Past studies suggest a wide range of volumes, from 10-300mL, as sufficient to make a diagnosis. However, the sensitivity for MPE diagnosis are low. Pleural fluid cells are heterogeneously distributed within the pleural cavity and larger volume samples may be more likely to recover malignant cells. There is no literature comparing the diagnostic yield of high volume pleural fluid samples (>1000mL) to low volume samples. Retrospective analysis of 233 thoracenteses from 2013 to 2017 was performed. Inclusion criteria were cases with known or suspected MPE with fluid sent for cytologic analysis by combined direct smear/cytospin and cell block preparations. Demographic, clinical, and procedural data were obtained from review of the medical records. Fluid samples were defined as large volume if greater than 1000mL and low volume if between 1mL and 1000mL. Statistical significance of outcomes between these volumes was measured using Pearson’s chi-squared test. 109 thoracentesis samples from 96 (42 female and 54 male) patients were sent for cytologic analysis in cases of known or suspected malignancy. 26 cases (24%) were positive for malignancy. Average volume for large volume samples was 1200mL ± 245 (range, 1000 to 1750mL) and for low volume samples was 63mL ± 135 (range, 2 to 800mL). 64% of large volume samples were positive for malignancy compared to 19% positivity in low volume samples. The rate of cytological detection of malignancy was significantly higher with large volume thoracentesis (p = 0.001). Large volume thoracentesis analysis allows for a significant improvement in cytological detection of malignancy when compared to low volume samples. Often, in practice a small sample is obtained for analysis and the remaining extracted fluid is discarded. This study emphasizes the need to implement analysis of larger volume samples (>1000mL) to improve the diagnostic yield for MPE.

Pleural manometry in patients with pleural diseases - the usefulness in clinical practice.

Although pleural manometry is a relatively simple medical procedure it is only occasionally used to follow pleural pressure (Ppl) changes during a therapeutic thoracentesis and pneumothorax drainage. As some studies showed that pleural pressure monitoring might be associated with significant advantages, pleural manometry has been increasingly evaluated in the last decade. The major clinical applications of pleural pressure measurements include: the prevention of complications associated with large volume thoracentesis, diagnosis and differentiation between various types of an unexpandable lung and a possible prediction of the efficacy of chest tube drainage in patients with spontaneous pneumothorax. It is well known that the therapeutic thoracentesis might be complicated by cough, chest discomfort, and rarely, by a life threatening condition called reexpansion pulmonary edema (RPE). The serious adverse events of thoracentesis are related to pleural pressure drop rather than to the volume of removed pleural effusion. The use of pleural manometry during pleural fluid withdrawal enables the evaluation of the relationship between withdrawn pleural fluid volume, pleural pressure changes and procedure related complications. Pleural pressure measurement is also an important tool to study the different mechanism of pneumothorax complicating the thoracentesis. Pleural manometry is critical for measurement of pleural elastance, diagnosis of an unexpandable lung and differentiation between trapped lung and lung entrapment. This usually has significant clinical implications in terms of further management of patients with pleural effusion. The paper is a comprehensive review presenting different aspects of pleural pressure measurement in clinical practice.

Clinical Utility of Routine Pleural Manometry During Large Volume Thoracentesis: A Multicenter Randomized Trial

Clinical Utility of Routine Pleural Manometry During Large Volume Thoracentesis: A Multicenter Randomized Trial

Effect of Noninvasive Positive Pressure Ventilation During Large Volume Thoracentesis on Pleural Manometry

SESSION TITLE: Pleural Disease SESSION TYPE: Original Investigation Poster PRESENTED ON: Wednesday, November 1, 2017 at 01:30 PM - 02:30 PM PURPOSE: It has been observed that the symptoms of chest pain during large volume thoracentesis and the possibility of re-expansion pulmonary edema occur due to a large drop in the intrapleural pressure during large volume thoracentesis. Due to these factors thoracenteses are frequently terminated prior to the removal of maximal volumes. Consequently, patients may have incomplete drainage or need for multiple procedures. This is an initial pilot study to determine whether the application of non-invasive positive pressure ventilation at a relatively low pressure (CPAP 5mm H2O) during large volume thoracentesis could prevent excessive drop in pleural pressure (pPl). METHODS: A prospective, randomized controlled, non-blinded study of 49 consecutive adults who underwent thoracentesis was performed. We compared the changes in opening and closing pPl using a pleural manometry in patients assigned to continuous positive airway pressure of 5 mmH2O (treatment group) and patients without CPAP (control group). The Mann Whitney U test was used to analyze the results. An independent t test was used to compare the average volume drained between the two groups. RESULTS: Patients treated with CPAP 5 mmH2O had a significantly smaller drop in pleural pressures as compared to patients without CPAP (median of -11cmH2O vs -17.5 cmH2O respectively, p = 0.006). The average volume drained was not statistically significant in the CPAP group (1380 ml) vs the non-CPAP group (1371ml) with a p value 0.953. CONCLUSIONS: Our study demonstrates that the application of CPAP at 5 mmH2O is an effective measure to minimize drops in intrapleural pressures during large volume thoracentesis. We did not collect data on patients’ adverse events post procedure. Further studies at potentially higher CPAP pressure, side effects recording and follow-up imaging are needed to evaluate if preventing the drop in Ppl with CPAP will directly correlate with symptoms and adverse effects. CLINICAL IMPLICATIONS: The application of CPAP during large volume thoracentesis is an effective measure to minimize drops in intrapleural pressures, potentially decreasing adverse effects during this procedure. DISCLOSURE: The following authors have nothing to disclose: Karla Cruz Morel, Jonathan Kass, Ziad Boujaoude, Rohan Arya, Diana Kolman, Wissam Abouzgheib No Product/Research Disclosure Information

Systematic Venoplasty: A Method To Treat Difficult Mechanical Hepatic Vein Outflow Obstruction in Orthotopic Liver Transplant

Mechanical hepatic venous outflow obstruction (HVOT) is rare but potentially serious complication of piggyback orthotropic liver transplant (OLT), which may result in graft loss. Endovascular stent placement or surgical repositioning are well described modalities of treatment. Venoplasty is rarely performed now-a-days as it is reported to be unsuccessful with high recurrence. We report here a case where successive angioplasty of hepatic vein lead to successful treatment of anatomically challenging and technically difficult HVOO. A 49-year-old African American female with hepatitis C cirrhosis underwent successful OLT at our institution. One month after transplant, patient developed gradually progressive abdominal distention and right sided pleural effusion. Fluid retention became diuretics refractory thus patient underwent 2 sessions of large volume thoracentesis for right hydrothorax and paracentesis for ascites. Subsequent evaluation with ultrasound liver with Doppler and CT showed significant stenosis of both right and left hepatic veins with narrowed middle hepatic vein and large venous infarcts. Endovascular stent placement was technically tough in our patient. Major concern regarding stent placement was difficult access due to unfavorable anatomy of anastomosis which could lead to stent malposition with high risk of migration or blocking the drainage of the other two hepatic veins completely. After multidisciplinary team discussion patient underwent two sessions of venoplasty of middle hepatic vein with systematic incremental balloon dilatations at one week interval to drop the pressure gradient across the anastomosis from 20 mm of Hg to 6 mm of Hg. One week post venoplasty, her hepatic hydrothorax and ascites resolved completely, without any recurrence over 2 months. In conclusion, successive angioplasty still could be used as a modality of treating anatomically unfavorable mechanical HVOO in piggyback OLT patient, who are not a candidate for endovascular stent.