Pleural effusions in the medical ICU: prevalence, causes, and clinical implications

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.

Focal Segmental Glomerulosclerosis Followed by Acute Hepatitis A Infection: Case Report

Background and Objectives: Chronic viral hepatitis such as hepatitis B or hepatitis C is frequently related to nephropathies, yet acute hepatitis A virus (HAV) infection is an exception. Materials and Methods: A 43-year-old male presented with jaundice accompanied by nausea and vomiting. The patient was diagnosed with acute HAV infection. Although the liver function improved after conservative treatment, various symptoms such as proteinuria, hypoalbuminemia, generalized edema and pleural effusion persisted. Due to nephrotic syndrome, the patient was referred to the clinic of the nephrology department and a renal biopsy was performed. Results: The result of the renal biopsy was focal segmental glomerulosclerosis (FSGS) based on histology, electron microscopy and immunohistochemistry. Therefore, based on the clinical history and biopsy results, the patient was diagnosed as having FSGS aggravated by acute HAV infection. Proteinuria, hypoalbuminemia and generalized edema were improved after prednisolone treatment. Conclusions: Although less common, acute HAV infection can also present with an extrahepatic manifestation, for example, FSGS. Hence, clinical attention is required if proteinuria or hypoalbuminemia persists in patients with acute HAV infection.

Temporary phrenic nerve stimulated patients: What is the role of ultrasound examination?

BACKGROUND

Prolonged mechanical ventilation caused by ventilator-induced diaphragm dysfunction (VIDD) is a serious problem in critically ill patients. Identification of patients who will have difficulty weaning from ventilation along with attempts to reduce total time on mechanical ventilation is some of the aims of intensive care medicine.

OBSERVATIONS

This article briefly summarizes current options for temporary phrenic nerve stimulation therapy in an effort to keep the diaphragm active as direct prevention and treatment of ventilator-associated diaphragmatic dysfunction in patients on mechanical ventilation. The results of feasibility studies using different approaches are promising but so far, the clinical relevance is low. One important question is which tool would reliably identify early signs of diaphragmatic dysfunction and also be useful in guiding therapy. The authors present a brief overview of the current options considering the advantages and disadvantages of the available examination modalities. Despite the fact that current data point out some limitations of ultrasound examination, we believe that it still has a unique position in the bedside examination of critically ill patients on mechanical ventilation.

CONCLUSION

Temporary phrenic nerve stimulation, regardless of the specific approach used, has the potential to directly treat or reverse VIDD, and ultrasound examination plays an important role in the comprehensive care of critically ill patients.

Imaging in the Intensive Care Unit

Radiology plays an important role in the management of the most seriously ill patients in the hospital. Over the years, continued advances in imaging technology have contributed to an improvement in patient care. However, even with such advances, the portable chest radiograph (CXR) remains one of the most commonly requested radiographic examinations. While they provide valuable information, CXRs remain relatively insensitive at revealing abnormalities and are often nonspecific. Chest computed tomography (CT) can display findings that are occult on CXR and is particularly useful at identifying and characterizing pleural effusions, detecting barotrauma including small pneumothoraces, distinguishing pneumonia from atelectasis, and revealing unsuspected or additional abnormalities which could result in increased morbidity and mortality if left untreated. CT pulmonary angiography is the modality of choice in the evaluation of pulmonary emboli which can complicate the hospital course of the ICU patient. This article will provide guidance for interpretation of CXR and thoracic CT images, discuss some of the invasive devices routinely used, and review the radiologic manifestations of common pathologic disease states encountered in ICU patients. In addition, imaging findings and complications of more specific clinical scenarios in which the incidence has increased in the ICU setting, such as patients who are immunocompromised, have interstitial lung disease, or COVID-19, will also be discussed. Communication between the radiologist and intensivist, particularly on complicated cases, is important to help increase diagnostic accuracy and leads to an improvement in the management of the most critically ill patients.

Serous fluids and hematolymphoid disorders

Diagnosing hematolymphoid neoplasm by evaluating fine-needle aspiration (FNA) cytology sample is controversial and requires experience and clinical skills. This concept becomes more challenging when evaluating hematolymphoid neoplasm in body fluid. Differentiating between low-grade lymphoma and reactive lymphocytes is often difficult by morphology alone as reactive lymphoid cells may acquire activation morphology from being exposed to different cytokines within the body fluid. However, in most cases there are specific features that may aid in differentiating small reactive from non-reactive lymphocytes including the round shape of the nucleus, the absence of visible nucleoli and the presence of fine clumped chromatin. In large cell lymphoma and leukemia cells involvement of body fluid this concept becomes less challenging. Large cell lymphoma and leukemia cells tend to have large size nuclei, less mature chromatin, and visible nucleoli with and without cytoplasmic vacuoles. However, to reach accurate diagnosis and subclassification, the utilizing of flow cytometry, to confirm monoclonality, and other ancillary studies such immunocytochemistry, cytogenetics and molecular studies is needed. This review article will be incorporated finally as one of the chapters in CMAS (CytoJournal Monograph/Atlas Series) #2. It is modified slightly from the chapter by the initial authors in the first edition of Diagnostic Cytopathology of Serous Fluids.

Pleural Effusions in the Critically Ill and "At-Bleeding-Risk" Population

Thoracentesis is a common bedside procedure, which has a low risk of complications when performed with thoracic ultrasound and by experienced operators. In critically ill or mechanically ventilated patients, or in patients with bleeding risks due to medications or other coagulopathies, the complication rate remains low. Drainage of pleural effusion in the intensive care unit has diagnostic and therapeutic utility, and perceived bleeding risks should be one part of an individualized and comprehensive risk-benefit analysis.

Transudative and Exudative Pleural Effusion in Chronic Kidney Disease Patients: A Prospective Single-Center Study

Objective The aim of the study is to assess the incidence of pleural effusion and to assess its etiology in admitted chronic kidney disease patients who were admitted secondary to various causes, i.e., fluid overload, sepsis, etc. Material and methods A prospective cross-sectional observational study was conducted at the Department of Nephrology, The Kidney Centre Postgraduate Training Institute, Karachi. A total of 789 patients were admitted between August 2020-February 2021. This study comprised 280 adult chronic kidney disease (chronic kidney disease and end-stage renal disease patients who were on dialysis) patients having pleural effusion (either unilateral or bilateral) secondary to various causes.  Results Among 280 patients, the mean age was 55 years with 158 (56.4%) males and 122 (43.6%) females, diabetes (76%) was present in most of the patients along with hypertension (86.1%), and most of the patients were of stage IV and V. Transudative pleural effusion was present in 212 (75.7%) patients secondary to fluid overload and heart failure was the commonest cause while 68 (24.3%) patients had exudative pleural effusion with tuberculosis being the commonest etiology, 44 (15.7%) patients needed intervention while 236 (84.3%) were treated medically. The data was entered and analyzed on SPSS version 21 (IBM Corp, Armonk, USA). The cleaning and coding of data were done before analysis. Continuous variables were expressed in mean ± standard deviation, while the frequencies with percentages were obtained for categorical variables. The Chi-square test was applied to see the association between variables. A p-value of ≤ 0.05 was considered significant. Conclusion Clarification of the cause of pleural effusion is essential. Early diagnosis and prompt treatment like thoracocentesis or in the case of patients on hemodialysis, adequate dialysis may be necessary.

Evaluation and management of pleural sepsis

Pleural sepsis stems from an infection within the pleural space typically from an underlying bacterial pneumonia leading to development of a parapneumonic effusion. This effusion is traditionally divided into uncomplicated, complicated, and empyema. Poor clinical outcomes and increased mortality can be associated with the development of parapneumonic effusions, reinforcing the importance of early recognition and diagnosis. Management necessitates a multimodal therapeutic strategy consisting of antimicrobials, catheter/tube thoracostomy, and at times, video-assisted thoracoscopic surgery.

Small Drainage Volumes of Pleural Effusions Are Associated with Complications in Critically Ill Patients: A Retrospective Analysis

Pleural effusions are a common finding in critically ill patients and small bore chest drains (SBCD) are proven to be efficient for pleural drainage. The data on the potential benefits and risks of drainage remains controversial. We aimed to determine the cut-off volume for complications, to investigate the impact of pleural drainage and drained volume on clinically relevant outcomes. Medical records of all critically ill patients undergoing insertion of SBCD were retrospectively examined. We screened 13,003 chest radiographs and included 396 SBCD cases in the final analysis. SBCD drained on average 900 mL, with less amount in patients with complications (p = 0.003). A drainage volume of 975 mL in 24 h represented the optimal threshold for complications. Pneumothorax was the most frequent complication (4.5%), followed by bleeding (0.8%). Female and lighter-weighted patients experienced a higher risk for any complication. We observed an improvement in the arterial partial pressure of oxygen and respiratory quotient (p < 0.001). We conclude that the small drainage volumes are associated with complications in critically ill patients—the more you drain, the safer the procedure gets. The use of SBCD is a safe and efficient procedure, further investigations regarding the higher rate of complications in female and lighter-weighted patients are desirable.

A pleural ultrasound image of a collapsed lung surrounded by pleural fluid ("jellyfish sign") may correspond to an intrapericardial mass

Lung ultrasound has been shown to be a valuable diagnostic tool. It has become the main way to get to the diagnosis of pleural effusion with much more specificity and sensibility than the x-ray. The diagnosis of pleural effusion with ultrasound is easily obtained after the visualization of hypoechoic fluid surrounding the lung. Sometimes it appears as an image of a collapsed lung moving with the surrounded pleural fluid ("jellyfish sign"). Until now this sign was almost pathognomonic of pleural effusion, but we explore a case in which this sign could have led to a misleading diagnosis. We present the case of a child admitted to intensive care with respiratory distress. In the point of care lung ultrasound we believed to see a pleural effusion with a collapsed lung moving into the effusion. Due to the enlargement of the pericardial sac, we did not realize that what we thought to be the pleural space was in fact the pericardial space. Unfortunately, there was a more echogenic area inside the pericardial effusion which led to a misleading fake lung atelectasis with pleural effusion ("jellyfish sign"). The correct diagnosis was properly obtained after assessing a cardiac point of care ultrasound using a four chambers view. The left side of the thorax is more difficult to be sonographed than the right due to the presence of the heart fossa that occupies a significant part of that side. Obtaining the diagnosis of pleural effusion on that side is more difficult for this reason and can sometimes be misleading with a pericardial effusion. The presence of the "jellyfish sign" is not pathognomonic and may lead to an error if we are guided only by the presence of that sign. To avoid such a misleading diagnosis, we highly recommend performing a point of care cardiac ultrasound if a pleural effusion is primarily seen in the lung ultrasound.

Application of Point-of-care Cardiac Ultrasonography in COVID-19 Infection: Lessons Learned from the Early Experience

The outbreak of the SARS-CoV-2 infection, also known as coronavirus disease 2019 (COVID-19), was formally defined a pandemic by the World Health Organization (WHO) in March 2020, and is still a global health issue. Since there is a high prevalence of acute cardiac injury in patients with COVID-19 infection, point-of-care cardiac ultrasound (PoCCUS) may be used for longitudinal monitoring of patients infected with COVID-19. However, there is still limited experience on the application of PoCCUS in the COVID-19 pandemic. Within the point of care setting in our system, focused cardiac US exams were performed with specific imaging protocols on the basis of suspicion of a specific disease, such as ruling out tamponade or thrombotic complications. Our preliminary experience shows that PoCCUS helps distinguish the causes of dyspnea in febrile patients. The COVID-19 infection may play a role in unmasking or exacerbating underlying chronic cardiovascular conditions, especially in patients with inadequate past history. In hospitalized patients with COVID-19, CURB-65 score for pneumonia severity and raised D-dimer were significantly associated with deep vein thrombosis (DVT). COVID-19 patients with DVT had worse prognosis, and patients with lower leg edema deserve further evaluation by using point-of-care ultrasound for the lower legs and heart. In COVID-19 patients with arrhythmia, PoCCUS used by experienced hands may reveal abnormal right ventricle (RV) functional parameters and lead to a more comprehensive cardiac US study. When there is suspicion of cardiac disease, PoCCUS can be done first, and if information is inadequate, limited transthoracic echocardiography (TTE), and critical care echocardiography (CCE) can be followed. Ultrasound practitioners should follow the standard precautions for COVID-19 as outlined by the Centers for Disease Control and Prevention to prevent transmission of infection, regardless of suspected or confirmed COVID-19.

Pleural effusion post coronary artery bypass surgery: associations and complications

Background

One of the most frequent complications of coronary artery bypass grafting (CABG) is pleural effusion. Limited previous studies have found post-CABG pleural effusion to be associated with increased length-of-stay and greater morbidity post-CABG. Despite this the associations of this common complication are poorly described. This study sought to identify modifiable risk factors for effusion post-CABG.

Methods

A retrospective cohort study of prospectively collected data assessed patients who underwent CABG over two-years. Data was collected for risk factors and sequelae related to pleural effusion requiring drainage.

Results

A total of 409 patients were included. Average age was 64.9±10.2 years, 330 (80.7%) were male. 59 (14.4%) patients underwent drainage of pleural effusion post-CABG. Effusions were drained on average 9.9±8.4 days post-CABG. Earlier removal of drain tubes and removal near time of extubation were associated with development of pleural effusion. Post-CABG pleural effusion was associated with post-operative renal impairment (P<0.01) and pericardial effusion (P<0.01). Patients with pleural effusion were more likely to require readmission to ICU (P<0.01), reintubation (P=0.03) and readmission to hospital (P=0.03).

Conclusions

Pleural effusion is a common complication of cardiac surgery and is associated with significant morbidity and resource utilization. This study identifies several associated complications that should be considered in the presence of pleural effusion. Modifiable associated factors in the management of drains that may contribute to accumulation of pleural effusion include: early removal of chest drains, higher outputs and removal during or close to mechanical ventilation. Further research is required to assess how adjusting these modifiable factors can decrease rates of effusion post-operatively.

The Use of Thoracic Ultrasound to Predict Transudative and Exudative Pleural Effusion

Objectives: Pleural effusion is a common reason for hospital admission with thoracentesis often required to diagnose an underlying cause. This study aimed to determine if the imaging characteristics of TUS effectively differentiates between transudative and exudative pleural fluid. Methods: Patients undergoing TUS with pleural fluid analysis were retrospectively identified at a single center between July 2016 and March 2018. TUS images were interpreted and characterized by established criteria. We determined diagnostic performance characteristics of image criteria to distinguish transudative from exudative pleural effusions. Results: 166 patients underwent thoracentesis for fluid analysis of which 48% had a known malignancy. 74% of the pleural effusions were characterized as exudative by Light's Criteria. TUS demonstrated anechoic effusions in 118 (71%) of samples. The presences of septations on TUS was highly specific in for exudative effusions (95.2%) with high positive predictive values (89.5%) and likelihood ratio (2.85). No TUS characteristics, even when adjusting for patient characteristics such as heart failure or malignancy, were sensitive for exudative effusions. Conclusions: Among our cohort, anechoic images did not allow reliable differentiation between transudative and exudative fluid. Presence of complex septated or complex homogenous appearance was high specific and predictive of exudative fluid.

Are pocket sized ultrasound devices sufficient in the evaluation of lung ultrasound patterns and aeration scoring in pulmonary ICU patients?

Lung ultrasound (LUS) is a practical diagnostic tool for several lung pathologies. Pocket sized USG devices (PSUDs) are more affordable, accessible, practical, and learning to use them is easier than standard ultrasound devices (SUDs). Their capability in image quality have been found as comparable with standard USG machines. Studies have been showing that these devices can be useful as much as SUDs in the evaluation of heart, abdomen, vascular structures, diaphragm and optic nerve. The aim of this study is to compare PSUD with a standard ultrasound devices (SUD) in the evaluation of LUS patterns such as alveolar, interstitial syndromes and lung aeration score (LAS). Study performed in an University Hospital Pulmonary ICU. All patients older than 18 years old were included in this study. The sector probe of SUD (Vivid-Q) and PSUD (Vscan) were used for investigation of A lines, interstitial (B lines), alveolar syndromes (consolidation, hepatisation, air bronchograms) and pleural effusion. 33 patients were included in the study. When PSUD was compared with SUD in terms of total B2 count, and LAS in the right, left and both lung, there was an agreement without proportional bias according to Bland Altman test. There was also good inter class correlation coefficient value as greater than 0.8 and 0.7 between two physicians in terms of counting of total B1, B2, total B lines and calculating of total LAS for SUD and PSUD respectively. PSUDs is a reliable and valid method for evaluation of LUS patterns like SUDs.

Lung Ultrasound Scanning for Respiratory Failure in Acutely Ill Patients: A Review

Lung ultrasonography (LUS), an imaging modality quickly performed, interpreted, and integrated by the treating physician at the bedside, is a particularly useful tool for acutely ill patients. In the evaluation of a patient with respiratory failure in the ICU or ED, LUS is superior to chest radiograph and generally comparable with CT imaging and reduces the need for patient transport and radiation exposure. This article will provide a concise review of LUS as it pertains to respiratory failure in general and will include examples of relevant ultrasound images and video clips from critically ill patients.

Effusion-Serum Chloride Gradient in Heart Failure-Associated Pleural Effusion - Pathophysiologic Implications

Background: There is scant clinical data of electrolyte analyses in the pleural fluid under heart failure (HF) pathophysiology.

Methods and Results: This study retrospectively analyzed data from 17 consecutive patients who presented with pleural effusion and underwent thoracentesis. A diagnosis of worsening HF was established by clinical criteria (presentation, echocardiography, serum B-type natriuretic peptide, and response to therapy). Samples of non-heparinized pleural fluid and peripheral venous blood, obtained within 2 h of each other, were subjected to biochemical analysis. The source of pleural effusion was determined as transudate or exudate according to Light’s criteria. Fifteen patients (53% men; mean [±SD] age 85±11 years) had HF-associated pleural effusion, 10 of whom had transudative effusion and 5 who had exudative effusion (fulfilling only 1 [n=4] or both [n=1] lactate dehydrogenase criteria). The effusion-serum gradient (calculated by subtracting the serum electrolyte concentration from the effusion electrolyte concentration) was significantly higher for chloride (mean [±SD] 7.4±2.6 mEq/L; range 4–14 mEq/L) than sodium (0.9±1.4 mEq/L; ranging from −1 to 4 mEq/L) and potassium (−0.1±0.3 mEq/L; ranging from −0.8 to 0.2 mEq/L; P<0.001 for each).

Conclusions: In HF-associated pleural effusion, the chloride concentration is higher in the pleural effusion than the serum, indicating that chloride may have an important role in the formation and retention of body fluid in the pleural space.

Methods of estimation of pleural effusion by ecography

Pleural effusion is a frequent pathology in intensive care units. The diagnosis has improved after the introduction of pulmonary ultrasound, an accessible method at the bedside, which allows not only the diagnosis but also the treatment of this entity. The aim of our study is to determine the accuracy of published mathematical equations to calculate the volume of pleural effusion from ultrasound measurements. After doing a systematic review, seven articles were selected that each proposed a mathematical equation. In all of them the results were statistically significant. However, there is no ideal formula among those studied.

Real-time ultrasound-guided thoracentesis in the intensive care unit: prevalence of mechanical complications

Background

The use of thoracic ultrasound during thoracentesis reduces complications. The aim of this study was to determine the prevalence of complications for real-time ultrasound-guided thoracentesis performed by intensivists. As a secondary objective, the change in oxygenation before and after the procedure was evaluated.

Patients and methods

An observational prospective study was conducted. A total of 81 cases of real-time ultrasound-guided thoracentesis performed by intensivists in the intensive care unit (ICU) of Méderi Major University Hospital, Bogotá, Colombia, between August 2018 and August 2019 were analyzed. Thoracentesis performed by interventional radiologists and using techniques different from the focus of this study were excluded from the analysis.

Results

There was one pneumothorax, for a prevalence rate of mechanical complications in this population of 1.2%. The mean partial oxygen pressure to inspired oxygen fraction ratio (PaO₂/FiO₂) prior to the procedure was 198.1 (95% CI 184.75–211.45), with a PaO₂/FiO₂ after the procedure of 224.6 (95% CI 213.08–226.12) (p < 0.05).

Conclusions

Real-time ultrasound-guided thoracentesis performed by intensivists is a safe procedure and leads to a significant improvement in oxygenation rates. Future studies are required to determine the impact of these results on other outcomes, such as mortality, ICU stay, and days of mechanical ventilation.

Clinically Significant Pleural Effusion in Intensive Care: A Prospective Multicenter Cohort Study

OBJECTIVES

The prevalence and optimal management of clinically significant pleural effusion, confirmed by thoracic ultrasound, in the critically ill is unknown. This study aimed to determine: 1) the prevalence, characteristics, and outcomes of patients treated in intensive care with clinically significant effusion and 2) the comparative efficacy and safety of pleural drainage or expectant medical management.

DESIGN

A prospective multicenter cohort study.

SETTING

ICUs in four teaching hospitals in Western Australia.

PATIENTS

Consecutive patients with clinically significant pleural effusions (depth ≥ 2 cm on thoracic ultrasound with clinician-determined adverse effects on patient progress).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Primary outcome was the change in Pao2:Fio2 (mm Hg) ratio from baseline to 24 hours. Changes in diagnosis and treatment based on pleural fluid analysis and pleural effusion related serious adverse events between those who underwent either drainage within 24 hours or expectant management were compared. Of the 7,342 patients screened, 226 patients (3.1%) with 300 pleural effusions were enrolled. Early drainage of pleural effusion occurred in 76 patients (34%) and significantly improved oxygenation (Pao2:Fio2 ratio 203 at baseline vs 263 at 24 hr, +29.6% increment; p < 0.01). This was not observed in the other 150 patients who had expectant management (Pao2:Fio2 ratio 250 at baseline vs 268 at 24 hr, +7.2% increment; p = 0.44). The improvement in oxygenation after early drainage remained unchanged after adjustment for a propensity score on the decision to initiate early drainage. Pleural effusion related serious adverse events were not different between the two groups (early drainage 10.5% vs no early drainage 16.0%; p = 0.32). Improvements in diagnosis were noted in 91 initial (nonrepetitive) drainages (76.5% out of 119); treatment strategy was optimized after 80 drainage episodes (59.7% out of 134).

CONCLUSIONS

Early drainage of clinically significant pleural effusion was associated with improved oxygenation and diagnostic accuracy without increased complications.

Pleural Effusion Outcomes in Intensive Care: Analysis of a Large Clinical Database

BACKGROUND

Pleural effusions are common in critically ill patients. However, the management of pleural fluid on relevant clinical outcomes is poorly studied. We evaluated the impact of pleural effusion in the intensive care unit (ICU).

METHODS

A large observational ICU database Multiparameter Intelligent Monitoring in Intensive Care III was utilized. Analyses used matched patients with the same admission diagnosis, age, gender, and disease severity.

RESULTS

Of 50 765, 3897 (7.7%) of critically ill adult patients had pleural effusions. Compared to patients without effusion, patients with effusion had higher in-hospital (38.7% vs 31.3%, P < .0001), 1-month (43.1% vs 36.1%, P < .0001), 6-month (63.6% vs 55.7%, P < .0001), and 1-year mortality (73.8% vs 66.1%, P < .0001), as well as increased length of hospital stay (17.6 vs 12.7 days, P < .0001), ICU stay (7.3 vs 5.1 days, P < .0001), need for mechanical ventilation (63.1% vs 55.7%, P < .0001), and duration of mechanical ventilation (8.7 vs 6.3 days, P < .0001). A total of 1503 patients (38.6%) underwent pleural fluid drainage. Patients in the drainage group had higher in-hospital (43.9% vs 35.4%, P = .0002), 1-month (47.7% vs 39.7%, P = .0005), 6-month (67.1% vs 61.8%, P = .0161), and 1-year mortality (77.1% vs 72.1%, P = .0147), as well as increased lengths of hospital stay (22.1 vs 16.0 days, P < .0001), ICU stay (9.2d vs 6.4 days, P < .0001), and duration of mechanical ventilation (11.7 vs 7.1 days, P < .0001).

CONCLUSIONS

The presence of a pleural effusion was associated with increased mortality in critically ill patients regardless of disease severity. Drainage of pleural effusion was associated with worse outcomes in a large, heterogeneous cohort of ICU patients.

Thoracic ultrasonography: a narrative review

This narrative review focuses on thoracic ultrasonography (lung and pleural) with the aim of outlining its utility for the critical care clinician. The article summarizes the applications of thoracic ultrasonography for the evaluation and management of pneumothorax, pleural effusion, acute dyspnea, pulmonary edema, pulmonary embolism, pneumonia, interstitial processes, and the patient on mechanical ventilatory support. Mastery of lung and pleural ultrasonography allows the intensivist to rapidly diagnose and guide the management of a wide variety of disease processes that are common features of critical illness. Its ease of use, rapidity, repeatability, and reliability make thoracic ultrasonography the "go to" modality for imaging the lung and pleura in an efficient, cost effective, and safe manner, such that it can largely replace chest imaging in critical care practice. It is best used in conjunction with other components of critical care ultrasonography to yield a comprehensive evaluation of the critically ill patient at point of care.

Utility of pleural effusion drainage in the ICU: An updated systematic review and META-analysis

PURPOSE

The effects on the respiratory or hemodynamic function of drainage of pleural effusion on critically ill patients are not completely understood. First outcome was to evaluate the PiO₂/FiO₂ (P/F) ratio before and after pleural drainage.

SECONDARY OUTCOMES

evaluation of A-a gradient, End-Expiratory lung volume (EELV), heart rate (HR), mean arterial pressure (mAP), left ventricular end-diastolic volume (LVEDV), stroke volume (SV), cardiac output (CO), ejection fraction (EF), and E/A waves ratio (E/A). A tertiary outcome: evaluation of pneumothorax and hemothorax complications.

MATERIALS AND METHODS

Searches were performed on MEDLINE, EMBASE, COCHRANE LIBRARY, SCOPUS and WEB OF SCIENCE databases from inception to June 2018 (PROSPERO CRD42018105794).

RESULTS

We included 31 studies (2265 patients). Pleural drainage improved the P/F ratio (SMD: -0.668; CI: -0.947-0.389; p < .001), EELV (SMD: -0.615; CI: -1.102-0.219; p = .013), but not A-a gradient (SMD: 0.218; CI: -0.273-0.710; p = .384). HR, mAP, LVEDV, SV, CO, E/A and EF were not affected. The risks of pneumothorax (proportion: 0.008; CI: 0.002-0.014; p = .138) and hemothorax (proportion: 0.006; CI: 0.001-0.011; p = .962) were negligible.

CONCLUSIONS

Pleural effusion drainage improves oxygenation of critically ill patients. It is a safe procedure. Further studies are needed to assess the hemodynamic effects of pleural drainage.

Early postoperative hypoalbuminaemia is associated with pleural effusion after donor hepatectomy: A propensity score analysis of 2316 donors

Pleural effusion and hypoalbuminaemia frequently occur after hepatectomy. Despite the emphasis on the safety of donors, little is known about the impact of postoperative albumin level on pleural effusion in liver donors. We retrospectively assessed 2316 consecutive liver donors from 2004 to 2014. The analysis of donors from 2004 to 2012 showed that postoperative pleural effusion occurred in 47.4% (970/2046), and serum albumin levels decreased until postoperative day 2 (POD2) and increased thereafter. In multivariable analysis, the lowest albumin level within POD2 (POD2ALB) was inversely associated with pleural effusion (OR 0.28, 95% CI 0.20-0.38; P < 0.001). POD2ALB ≤3.0 g/dL, the cutoff value at the 75th percentile, was associated with increased incidence of pleural effusion after propensity score (PS) matching (431 pairs; OR 1.69, 95% CI 1.30-2.21; P < 0.001). When we further analysed data from 2010 to 2014, intraoperative albumin infusion was associated with higher POD2ALB (P < 0.001) and lower incidence of pleural effusion (P = 0.024), compared with synthetic colloid infusion after PS matching (193 pairs). In conclusion, our data showed that POD2ALB is inversely associated with pleural effusion, and that intraoperative albumin infusion is associated with a lower incidence of pleural effusion when compared to synthetic colloid infusion in liver donors.

Pleural effusion during weaning from mechanical ventilation: a prospective observational multicenter study

Background

Pleural effusion is common during invasive mechanical ventilation, but its role during weaning is unclear. We aimed at assessing the prevalence and risk factors for pleural effusion at initiation of weaning. We also assessed its impact on weaning outcomes and its evolution in patients with difficult weaning.

Methods

We performed a prospective multicenter study in five intensive care units in France. Two hundred and forty-nine patients were explored using ultrasonography. Presence of moderate-to-large pleural effusion (defined as a maximal interpleural distance ≥ 15 mm) was assessed at weaning start and during difficult weaning.

Results

Seventy-three (29%) patients failed weaning, including 46 (18%) who failed the first spontaneous breathing trial (SBT) and 39 (16%) who failed extubation. Moderate-to-large pleural effusion was detected in 81 (33%) patients at weaning start. Moderate-to-large pleural effusion was associated with more failures of the first SBT [27 (33%) vs. 19 (11%), p < 0.001], more weaning failures [37 (47%) vs. 36 (22%), p < 0.001], less ventilator-free days at day 28 [21 (5–24) vs. 23 (16–26), p = 0.01], and a higher mortality at day 28 [14 (17%) vs. 14 (8%), p = 0.04]. The association of pleural effusion with weaning failure persisted in multivariable analysis and sensitivity analyses. Short-term (48 h) fluid balance change was not associated with the evolution of interpleural distance in patients with difficult weaning.

Conclusions

In this multicenter observational study, pleural effusion was frequent during the weaning process and was associated with worse weaning outcomes.

Electronic supplementary material

The online version of this article (10.1186/s13613-018-0446-y) contains supplementary material, which is available to authorized users.

An easier and safe affair, pleural drainage with ultrasound in critical patient: a technical note

Thoracic ultrasound is a powerful diagnostic imaging technique for pleural space disorders. In addition to visualising pleural effusion, thoracic ultrasound also helps clinicians to identify the best puncture site and to guide the drainage insertion procedure. Thoracic ultrasound is essential during these invasive manoeuvres to increase safety and decrease potential life-threatening complications. This paper provides a technical description of pigtail-type drainage insertion using thoracic ultrasound, paying particular attention to indications, contraindications, ultrasound guidance, preparation/equipment, procedure and complications.

Lung Ultrasound Findings Detected During Inpatient Echocardiography Are Common and Associated With Short- and Long-term Mortality

OBJECTIVES

Although pulmonary abnormalities are easily seen with standard echocardiography or pocket-sized ultrasound devices, we sought to observe the prevalence of lung ultrasound apical B-lines and pleural effusions and their associations with inpatient, 1-year, and 5-year mortality when found in hospitalized patients referred for echocardiography.

METHODS

We reviewed 486 initial echocardiograms obtained from consecutive inpatients over a 3-month period, in which each examination included 4 supplemental images of the apex and the base of both lungs. Kaplan-Meier survival curves were used to compare mortality rates among patients with versus without lung findings. Cox proportional hazard regression was used to determine the relative contributions of age, sex, effusions, and B-lines to overall mortality.

RESULTS

Of the 486 studies, the mean patient age ± SD was 68 ± 17 years; the median age was 70 years (interquartile range, 27 years); and 191 (39%) had abnormal lung findings. The presence versus absence of abnormal lung findings was related to initial-hospital (8.9% versus 2.0%; P = .001), 1-year (33% versus 14%; P < .001), and 5-year (56% versus 31%; P < .001) mortality. Ultrasound apical B-lines and pleural effusions were both independently associated with increased mortality during initial hospitalization (hazard ratio [HR], 4.3; 95% confidence interval [CI], 1.7-11.0; and HR, 2.5; 95% CI, 1.1-6.0, respectively). Pleural effusions were also associated with increased 1-year mortality (HR, 2.3; 95% CI, 1.5-3.4).

CONCLUSIONS

In hospitalized patients undergoing echocardiography, the simple addition of 4 quick 2-dimensional pulmonary views to the echocardiogram often detects abnormal findings that have important implications for short- and long-term mortality.

Bedside pleuroscopy in the Intensive Care Unit

Objectives:

It is not always possible to move critically ill patients to the operating or endoscopy room for a pleuroscopy. Bedside pleuroscopy is indicated for these patients. The aim of this study was to investigate the safety and complications of bedside pleuroscopy in an Intensive Care Unit (ICU).

Materials and Methods:

The patients who had undergone routine examinations for pleural effusion, with no established diagnosis at the previous admission were included in this analysis. Patients received local analgesia with bedside pleuroscopy performed by a chest physician in the ICU with continuous monitoring.

Results:

Twenty-five patients (17 males and 8 females) with a mean age of 74 ± 3 years were enrolled. Their mean APACHE II score was 23 ± 1. The duration of drainage from the pigtail catheter was a mean 3.9 ± 0.2 days, and mean ventilator usage was 6 ± 0.7 days. The length of stay in the ICU was 11 ± 1 days. Most pleural effusions occurred on the right side (17/25, 68%). Fifteen patients (60%) had malignant effusions, four (16%) had parapneumonic effusions, three (12%) had empyema, and two (8%) had tuberculosis. Complications occurred in 11 (44%) patients. There were no major complications such as bleeding or procedure-related death. The most common complication was transient chest pain (n = 6, 24%).

Conclusions:

Pleuroscopy performed at the bedside in the ICU is a simple and safe procedure. It has the potential for use in critical patients as serious complications are rare.

Thoracic ultrasound for pleural effusion in the intensive care unit: a narrative review from diagnosis to treatment

Pleural effusion (PLEFF), mostly caused by volume overload, congestive heart failure, and pleuropulmonary infection, is a common condition in critical care patients. Thoracic ultrasound (TUS) helps clinicians not only to visualize pleural effusion, but also to distinguish between the different types. Furthermore, TUS is essential during thoracentesis and chest tube drainage as it increases safety and decreases life-threatening complications. It is crucial not only during needle or tube drainage insertion, but also to monitor the volume of the drained PLEFF. Moreover, TUS can help diagnose co-existing lung diseases, often with a higher specificity and sensitivity than chest radiography and without the need for X-ray exposure. We review data regarding the diagnosis and management of pleural effusion, paying particular attention to the impact of ultrasound. Technical data concerning thoracentesis and chest tube drainage are also provided.

Fluid loading and norepinephrine infusion mask the left ventricular preload decrease induced by pleural effusion

Background

Pleural effusion (PLE) may lead to low blood pressure and reduced cardiac output. Low blood pressure and reduced cardiac output are often treated with fluid loading and vasopressors. This study aimed to determine the impact of fluid loading and norepinephrine infusion on physiologic determinants of cardiac function obtained by ultrasonography during PLE.

Methods

In this randomised, blinded, controlled laboratory study, 30 piglets (21.9 ± 1.3 kg) had bilateral PLE (75 mL/kg) induced. Subsequently, the piglets were randomised to intervention as follows: fluid loading (80 mL/kg/h for 1.5 h, n = 12), norepinephrine infusion (0.01, 0.03, 0.05, 0.1, 0.2 and 0.3 μg/kg/min (15 min each, n = 12)) or control (n = 6). Main outcome was left ventricular preload measured as left ventricular end-diastolic area. Secondary endpoints included contractility and afterload as well as global measures of circulation. All endpoints were assessed with echocardiography and invasive pressure-flow measurements.

Results

PLE decreased left ventricular end-diastolic area, mean arterial pressure and cardiac output (p values < 0.001), but fluid loading (20 mL/kg) and norepinephrine infusion (0.05 μg/kg/min) restored these values (p values > 0.05) to baseline. Left ventricular contractility increased with norepinephrine infusion (p = 0.002), but was not affected by fluid loading (p = 0.903). Afterload increased in both active groups (p values > 0.001). Overall, inferior vena cava distensibility remained unchanged during intervention (p values ≥ 0.085). Evacuation of PLE caused numerical increases in left ventricular end-diastolic area, but only significantly so in controls (p = 0.006).

Conclusions

PLE significantly reduced left ventricular preload. Both fluid and norepinephrine treatment reverted this effect and normalised global haemodynamic parameters. Inferior vena cava distensibility remained unchanged.

The haemodynamic significance of PLE may be underestimated during fluid or norepinephrine administration, potentially masking the presence of PLE.

Prevalence and Impact on Weaning of Pleural Effusion at the Time of Liberation from Mechanical Ventilation: A Multicenter Prospective Observational Study

BACKGROUND

Pleural effusion is frequent in intensive care unit patients, but its impact on the outcome of weaning remains unknown.

METHODS

In a prospective study performed in three intensive care units, pleural ultrasound was performed at the first spontaneous breathing trial to detect and quantify pleural effusion (small, moderate, and large). Weaning failure was defined by a failed spontaneous breathing trial and/or extubation requiring any form of ventilatory support within 48 h. The primary endpoint was the prevalence of pleural effusion according to weaning outcome.

RESULTS

Pleural effusion was detected in 51 of 136 (37%) patients and was quantified as moderate to large in 18 (13%) patients. As compared to patients with no or small pleural effusion, their counterparts were more likely to have chronic renal failure (39 vs. 7%; P = 0.01), shock as the primary reason for admission (44 vs. 19%; P = 0.02), and a greater weight gain (+4 [0 to 7] kg vs. 0 [-1 to 5] kg; P = 0.02). The prevalence of pleural effusion was similar in weaning success and weaning failure patients (odds ratio, 1.23; 95% CI, 0.61 to 2.49; P = 0.56), as was the prevalence of moderate to large pleural effusion (odds ratio, 0.89; 95% CI, 0.33 to 2.41; P = 1.00). Duration of mechanical ventilation and intensive care unit length of stay were similar between patients with no or small pleural effusion and those with moderate to large pleural effusion.

CONCLUSIONS

Significant pleural effusion was observed in 13% of patients at the time of liberation from mechanical ventilation and was not associated with an alteration of weaning outcome. (ANESTHESIOLOGY 2017; 126:1107-15).

Dobutamine aggravates haemodynamic deterioration induced by pleural effusion: A randomised controlled porcine study

BACKGROUND

Pleural effusion is a common finding in critically ill patients and may contribute to circulatory instability and the need for inotropic support.

OBJECTIVE

We hypothesised that dobutamine would affect the physiological determinants preload, afterload, contractility and changes of inferior vena cava characteristics during experimental pleural effusion.

DESIGN

A randomised, controlled laboratory study.

SETTING

Animal laboratory, conducted from March 2013 to May 2013.

ANIMALS

Twenty-four Landrace and Yorkshire female piglets (21.3 ± 1.7 kg).

INTERVENTION

Twenty piglets were included in the analyses. After inducing bilateral pleural effusion (30 ml kg), the piglets were block randomised to either incremental dobutamine infusion (n = 10) or control (n = 10).

MAIN OUTCOME MEASURES

Ultrasonographic measures of left ventricular end-diastolic area, left ventricular afterload, left ventricular fractional area change and inferior vena cava diameter and distensibility were used to assess the basic physiological effect of incremental dobutamine administration during experimental pleural effusion.

RESULTS

In the dobutamine group, preload, measured as left ventricular end-diastolic area, decreased from 11.3 ± 2.0 cm after creation of the pleural effusion to 8.1 ± 1.5 cm at a dobutamine infusion rate of 20 μg kg min (P < 0.001). In the same period, central venous pressure and the expiratory diameter of the inferior vena cava decreased from 9 ± 3 to 7 ± 4 mmHg (P < 0.001) and from 1.1 ± 0.2 to 0.9 ± 0.1 cm (P = 0.008), respectively.

CONCLUSION

In a porcine model of pleural effusion, dobutamine affected basic haemodynamic determinants substantially by decreasing left ventricular preload. Changes in central venous pressure and inferior vena cava characteristics were minimal, discouraging their use as indices of preload. This study underlines the significance of evaluating basic haemodynamic determinants to avoid inappropriate, potentially harmful treatment.

Toward a Blood-Borne Biomarker of Chronic Hypoxemia: Red Cell Distribution Width and Respiratory Disease

Hypoxemia (systemic oxygen desaturation) marks the presence, risk, and progression of many diseases. Episodic or nocturnal hypoxemia can be challenging to detect and quantify. A sensitive, specific, and convenient marker of recent oxygen desaturation represents an unmet medical need. Observations of acclimatization to high altitude in humans and animals reveals several proteosomic, ventilatory, and hematological responses to low oxygen tension. Of these, increased red cell distribution width (RDW) appears to have the longest persistence. Literature review and analyses of a 2M patient database across the full disease pathome revealed that increased RDW is predictive of poor outcome for certain diseases including many if not all hypoxigenic conditions. Comprehensive review of diseases impacting the respiratory axis show many are associated with increased RDW and no apparent counterexamples. The mechanism linking RDW to outcome is unknown. Conjectural roles for iron deficiency, inflammation, and oxidative stress have not been born out experimentally. Sports-doping studies show that erythropoietin (EPO) injection can induce formation of unusually large red blood cells (RBC) in sufficient numbers to increase RDW. Because endogenous EPO responds strongly to hypoxemia, this molecule could potentially mediate a long-lived RDW response to low oxygenation. RDW may be a guidepost signaling that unexploited information is embedded in subtle RBC variation. Applying modern techniques of measurement and analysis to certain RBC characteristics may yield a more specific and sensitive marker of chronic pulmonary and circulatory diseases, sleep apnea, and opioid inhibition of breathing.

Safety and Value of Thoracentesis in Medical ICU Patients

The objective of this study was to determine the safety and value of thoracentesis in an ICU, Thoracentesis is a safe procedure for critically ill patients, even those on mechanical ventilators, and usually confirms the suspected diagnosis. However, thoracentesis revealed an unexpected diagnosis that changed management in 12% of patients. Repeat or contralateral thoracentesis is indicated when either the clinical course is inconsistent or may represent a complication of the original diagnosis.

Risk factors for postoperative pulmonary complications in coronary artery bypass graft surgery patients

Background

Despite numerous advances in anesthesia, surgical techniques, and postoperative care for coronary artery bypass graft (CABG) surgery, postoperative pulmonary complications (PPCs) still account for postoperative morbidity.

Objective

To determine current risk factors for PPCs in CABG surgery patients.

Methods

A retrospective cohort design was used. Health records were reviewed for patients ( n=315) who had CABG surgery at a large quaternary healthcare center over a 4 month period. Pre-, peri-, and postoperative risk factors for PPCs were recorded as binary variables. Data were further assessed according to PPCs and non-PPCs using logistic regression models.

Results

PPCs occurred in 99.4% of this CABG surgical cohort. Atelectasis, pleural effusion, atelectasis with pleural effusion, and pneumonia were the most frequent PPCs post CABG surgery. Age >65 years, diabetes, and ASA classification N3 were found to be related to the presence of atelectasis. No significant risk factors were related to the development of pleural effusion or atelectasis with pleural effusion. Postoperative pneumonia was associated with previous myocardial infarction, ventilation >10 h, and hospital stay >5 days. History of bronchitis and COPD were related to postoperative pneumothorax; history of heart failure, COPD, and other lung diseases were related to postoperative pulmonary edema.

Conclusion

These findings contribute to the understanding of PPCs in post-CABG surgery patients and assist in identification of patients at risk for developing PPCs.

Clinical implications of pleural effusion in patients with acute type B aortic dissection

BACKGROUND

Pleural effusion may complicate acute Stanford type B aortic dissection (ABAD).

AIMS

To identify the relationships between the quantity and side of the pleural effusion, biomarkers and outcomes in patients with ABAD.

METHODS

We undertook a retrospective review of 105 patients with ABAD. Their demographics, the data on admission and during hospital stay, the volume of pleural effusion calculated from the area on computed tomography images and clinical outcomes were analysed.

RESULTS

The median estimated peak volume (median 6.7 days after onset) was 129 ml (63-192, range 26-514 ml) on the left and 11 ml (6-43, range 2-300 ml) on the right. On univariate analysis, the volume of bilateral effusions was associated with anaemia, hypoalbuminaemia and inflammatory markers, whereas the volume of left-sided effusions was associated with older age, low diastolic blood pressure and maximum aortic diameter. Multivariate analysis revealed that hypoalbuminaemia was independently associated with bilateral effusion volume ( P<0.001), while maximum aortic diameter was associated with left-sided effusion volume ( P=0.019). A greater volume of bilateral plural effusion was associated with longer intensive care unit stay.

CONCLUSIONS

Larger bilateral pleural effusions in patients with ABAD were associated with hypoalbuminaemia and potentially with anaemia and inflammation, and may increase the length of intensive care unit stay. Left-sided effusion volume appears to be influenced by the nature of the aortic dilatation. Multiple mechanisms may underpin the development of pleural effusion in ABAD, and are likely to influence clinical outcomes.

Intraoperative lung ultrasound: A clinicodynamic perspective

In the era of evidence-based medicine, ultrasonography has emerged as an important and indispensable tool in clinical practice in various specialties including critical care. Lung ultrasound (LUS) has a wide potential in various surgical and clinical situations for timely and easy detection of an impending crisis such as pulmonary edema, endobronchial tube migration, pneumothorax, atelectasis, pleural effusion, and various other causes of desaturation before it clinically ensues to critical level. Although ultrasonography is frequently used in nerve blocks, airway handling, and vascular access, LUS for routine intraoperative monitoring and in crisis management still necessitates recognition. After reviewing the various articles regarding the use of LUS in critical care, we found, that LUS can be used in various intraoperative circumstances similar to Intensive Care Unit with some limitations. Except for few attempts in the intraoperative detection of pneumothorax, LUS is hardly used but has wider perspective for routine and crisis management in real-time. If anesthesiologists add LUS in their routine monitoring armamentarium, it can assist to move a step ahead in the dynamic management of critically ill and high-risk patients.

Radiology in the Intensive Care Unit (Part 2)

This review of intensive care unit (ICU) radiology has been divided into two sections. In Part 1, previously published, the discussion focused on the role of the portable radiograph in the evaluation of the critically ill patient and the impact of the introduction of digital radiography and picture-archiving communications systems on patient care. Part 2 of this review will emphasize the role of computed tomography and the increasing contribution of image-guided interventional procedures in patient management. The deleterious effects of mechanical ventilation due to barotrauma will also be discussed.

Extent of pleural effusion on chest radiograph is associated with failure of high-flow nasal cannula oxygen therapy

PURPOSE

The purpose of the study was to determine whether pleural effusion (PE) is associated with a failure of high-flow nasal cannula (HFNC) therapy.

MATERIALS AND METHODS

We conducted a single-center retrospective study. Seventy-three patients with acute respiratory failure given HFNC therapy between January 2012 and December 2014 were reviewed. HFNC failure was defined as intubation or noninvasive positive pressure ventilation following HFNC therapy. The numbers of quadrants with consolidation or ground glass opacity were counted on chest radiographs performed within 24 hours before starting HFNC therapy, and the PE score was calculated. PE score was the original score, verified by the computed tomographic images of some of the study patients.

RESULTS

Overall, 29 of 73 experienced HFNC failure. PE score was significantly greater in the HFNC failure group, but the number of quadrants with opacity was not significantly different. Age and Sequential Organ Failure Assessment (SOFA) score were significantly greater in the HFNC failure group. The PE (odds ratio, 1.49; 95% confidence interval, 1.10-2.02; P = .01) and SOFA (odds ratio, 1.33; 95% confidence interval, 1.05-1.68; P = .02) scores were independently associated with HFNC failure in multivariate analysis.

CONCLUSIONS

The extent of PE on chest radiograph and SOFA score were associated with HFNC failure.

Ultrasound in the diagnosis and management of pleural effusions

We review the literature on the use of point-of-care ultrasound to evaluate and manage pleural effusions. Point-of-care ultrasound is more sensitive than physical exam and chest radiography to detect pleural effusions, and avoids many negative aspects of computerized tomography. Additionally, point-of-care ultrasound can assess pleural fluid volume and character, revealing possible underlying pathologies and guiding management. Thoracentesis performed with ultrasound guidance has lower risk of pneumothorax and bleeding complications. Future research should focus on the clinical effectiveness of point-of-care ultrasound in the routine management of pleural effusions and how new technologies may expand its clinical utility.

Extension of the Thoracic Spine Sign: A New Sonographic Marker of Pleural Effusion

OBJECTIVES

Dyspnea is a common emergency department (ED) condition, which may be caused by pleural effusion and other thoracic diseases. We present data on a new sonographic marker, the extension of the thoracic spine sign, for diagnosis of pleural effusion.

METHODS

In this prospective study, we enrolled a convenience sample of undifferentiated patients who underwent computed tomography (CT) of the abdomen or chest, which was performed as part of their emergency department evaluations. Patients underwent chest sonography to assess the utility of the extension of the thoracic spine sign for diagnosing pleural effusion. The point-of-care sonographic examinations were performed and interpreted by emergency physicians who were blinded to information in the medical records. Sonographic results were compared to radiologists' interpretations of the CT results, which were considered the criterion standard.

RESULTS

Forty-one patients were enrolled, accounting for 82 hemithoraces. Seven hemithoraces were excluded from the analysis due to various limitations, leaving 75 hemithoraces for the final analysis. The median time for completion of the sonographic examination was 3 minutes. The sensitivity and specificity for extension of the thoracic spine were 73.7% (95% confidence interval [CI], 48.6%-89.9%) and 92.9% (95%CI, 81.9%-97.7%), respectively. Overall, there were 5 hemithoraces with false-negative results when using the extension sign. Of those 5 cases, 4 were found to have trace pleural effusions on CT. When trace pleural effusions were excluded in a subgroup analysis, the sensitivity and specificity of extension of the thoracic spine were 92.9% (95% CI, 64.2%-99.6%) and 92.9% (95% CI, 81.9%-97.7%).

CONCLUSIONS

We found the extension of the thoracic spine sign to be an excellent diagnostic tool for clinically relevant pleural effusion.

Effects of pleural effusion drainage on oxygenation, respiratory mechanics, and hemodynamics in mechanically ventilated patients

OBJECTIVES

In mechanically ventilated patients, the effect of draining pleural effusion on oxygenation is controversial. We investigated the effect of large pleural effusion drainage on oxygenation, respiratory function (including lung volumes), and hemodynamics in mechanically ventilated patients after ultrasound-guided drainage. Arterial blood gases, respiratory mechanics (airway, pleural and transpulmonary pressures, end-expiratory lung volume, respiratory system compliance and resistance), and hemodynamics (blood pressure, heart rate, and cardiac output) were recorded before and at 3 and 24 hours (H24) after pleural drainage. The respiratory settings were kept identical during the study period.

MEASUREMENTS AND MAIN RESULTS

The mean volume of effusion drained was 1,579 ± 684 ml at H24. Uncomplicated pneumothorax occurred in two patients. Respiratory mechanics significantly improved after drainage, with a decrease in plateau pressure and a large increase in end-expiratory transpulmonary pressure. Respiratory system compliance, end-expiratory lung volume, and PaO2/FiO2 ratio all improved. Hemodynamics were not influenced by drainage. Improvement in the PaO2/FiO2 ratio from baseline to H24 was positively correlated with the increase in end-expiratory lung volume during the same time frame (r = 0.52, P = 0.033), but not with drained volume. A high value of pleural pressure or a highly negative transpulmonary pressure at baseline predicted limited lung expansion following effusion drainage. A lesser improvement in oxygenation occurred in patients with ARDS.

CONCLUSIONS

Drainage of large (≥500 ml) pleural effusion in mechanically ventilated patients improves oxygenation and end-expiratory lung volume. Oxygenation improvement correlated with an increase in lung volume and a decrease in transpulmonary pressure, but was less so in patients with ARDS.

A stepwise approach to the etiologic diagnosis of pleural effusion in respiratory intensive care unit and short-term evaluation of treatment

Background:

Pleural effusions in respiratory intensive care unit (RICU) are associated with diseases of varied etiologies and often carry a grave prognosis. This prospective study was conducted to establish an etiologic diagnosis in a series of such patients before starting treatment.

Materials and Methods:

Fifty consecutive patients, diagnosed with pleural effusion on admission or during their stay in RICU, were further investigated by a two-step approach. (1) Etiologic diagnosis was established by sequential clinical history and findings on physical examination, laboratory tests, chest radiograph, CECT/HRCT/PET-CT and pleural fluid analysis. (2) Patients who remained undiagnosed were subjected to fiber-optic bronchoscopy, video-assisted thoracoscopic pleural biopsy, and histopathology.

Results:

Etiologic diagnosis of pleural effusion was established in 44 (88%) Metastases (24%); para-pneumonia (22%); congestive cardiac failure (18%); tuberculosis (14%); hemothorax (4%); trapped lung, renal failure, and liver cirrhosis (2% each). Six patients (12%) remained undiagnosed, as the final diagnostic thoracoscopic biopsy could not be performed in five and tissue histopathology findings were inconclusive in one. Out of the 50 patients, 10 died in the hospital; 2 left against medical advice; and 2 were referred to oncology center for further treatment. The remaining 36 patients were clinically stabilized and discharged. During a 3-month follow-up, eight of them were re-hospitalized, of which four died.

Conclusions:

Pleural effusion in RICU carries a high risk of mortality. Etiologic diagnosis can be established in most cases.

Fluid overload in patients with severe sepsis and septic shock treated with early goal-directed therapy is associated with increased acute need for fluid-related medical interventions and hospital death

Early goal-directed therapy (EGDT) consists of early, aggressive fluid resuscitation and is known to improve survival in sepsis. It is unknown how often EGDT leads to subsequent fluid overload and whether post-EGDT fluid overload affects patients' outcomes. Our hypothesis was that patients with sepsis treated with EGDT were at risk for fluid overload and that fluid overload would be associated with adverse outcomes. We conducted a retrospective cohort of 405 consecutive patients admitted with severe sepsis and septic shock to the medical intensive care unit of a tertiary care academic hospital from January 2008 to December 2009. Baseline demographics, daily weights, fluid status, clinical or radiographic evidence of fluid overload, and medical interventions (thoracentesis, paracentesis, diuretic use, and ultrafiltration) were abstracted, and associations explored using univariate and multivariate logistic and linear regression analyses. At day 1, 67% of patients developed evidence of fluid overload, and in 48%, fluid overload persisted to day 3. Interrater agreement for presence of fluid overload was substantial (κ = 0.7). An increased trend in weight was noted in those with persistent clinical and radiologic evidence of fluid overload, but not with recorded positive fluid balance. When adjusted for baseline severity of illness, fluid overload was associated with increased use of fluid-related medical interventions (thoracentesis and diuretics) and hospital mortality (odds ratio, 1.92; confidence interval, 1.16-3.22). In patients with severe sepsis and septic shock treated with EGDT, clinical evidence of persistent fluid overload is common and is associated with increased use of medical interventions and hospital mortality.

Bedside ultrasonography: Applications in critical care: Part I

There is increasing interest in the use of ultrasound to assess and guide the management of critically ill patients. The ability to carry out quick examinations by the bedside to answer specific clinical queries as well as repeatability are clear advantages in an acute care setting. In addition, delays associated with transfer of patients out of the Intensive Care Unit (ICU) and exposure to ionizing radiation may also be avoided. Ultrasonographic imaging looks set to evolve and complement clinical examination of acutely ill patients, offering quick answers by the bedside. In this two-part narrative review, we describe the applications of ultrasonography with a special focus on the management of the critically ill. Part I explores the utility of echocardiography in the ICU, with emphasis on its usefulness in the management of hemodynamically unstable patients. We also discuss lung ultrasonography - a vastly underutilized technology for several years, until intensivists began to realize its usefulness, and obvious advantages over chest radiography. Ultrasonography is rapidly emerging as an important tool in the hands of intensive care physicians.