Pneumothorax and the value of chest radiography after ultrasound-guided thoracocentesis

Ultrasound-Guided Pleural Investigations: Fluid, Air, and Biopsy

Pleural diseases are frequently encountered across multiple inpatient and outpatient settings, making pleural drainage and sampling one of the most common medical procedures. With the widespread adoption of bedside ultrasound examination, ultrasound machines are now readily available in many clinical settings, providing both diagnostic and procedural guidance. The modern management of pleural disease is dominated by ultrasound assessment with strong evidence supporting its use to guide pleural interventions. Here, we review the current landscape of ultrasound use to guide pleural drainage, pneumothorax management, and pleural biopsy.

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.

Recommendations on the Use of Ultrasound Guidance for Adult Thoracentesis: A Position Statement of the Society of Hospital Medicine

Executive Summary: 1) We recommend that ultrasound should be used to guide thoracentesis to reduce the risk of complications, the most common being pneumothorax. 2) We recommend that ultrasound guidance should be used to increase the success rate of thoracentesis. 3) We recommend that ultrasound-guided thoracentesis should be performed or closely supervised by experienced operators. 4) We suggest that ultrasound guidance be used to reduce the risk of complications from thoracentesis in mechanically ventilated patients. 5) We recommend that ultrasound should be used to identify the chest wall, pleura, diaphragm, lung, and subdiaphragmatic organs throughout the respiratory cycle before selecting a needle insertion site. 6) We recommend that ultrasound should be used to detect the presence or absence of an effusion and approximate the volume of pleural fluid to guide clinical decision-making. 7) We recommend that ultrasound should be used to detect complex sonographic features, such as septations, to guide clinical decision-making regarding the timing and method of pleural drainage. 8) We suggest that ultrasound be used to measure the depth from the skin surface to the parietal pleura to help select an appropriate length needle and determine the maximum needle insertion depth. 9) We suggest that ultrasound be used to evaluate normal lung sliding pre- and postprocedure to rule out pneumothorax. 10) We suggest avoiding delay or interval change in patient position from the time of marking the needle insertion site to performing the thoracentesis. 11) We recommend against performing routine postprocedure chest radiographs in patients who have undergone thoracentesis successfully with ultrasound guidance and are asymptomatic with normal lung sliding postprocedure. 12) We recommend that novices who use ultrasound guidance for thoracentesis should receive focused training in lung and pleural ultrasonography and hands-on practice in procedural technique. 13) We suggest that novices undergo simulation-based training prior to performing ultrasound-guided thoracentesis on patients. 14) Learning curves for novices to become competent in lung ultrasound and ultrasound-guided thoracentesis are not completely understood, and we recommend that training should be tailored to the skill acquisition of the learner and the resources of the institution.

Safe and Effective Bedside Thoracentesis: A Review of the Evidence for Practicing Clinicians

BACKGROUND

Physicians often care for patients with pleural effusion, a condition that requires thoracentesis for evaluation and treatment. We aim to identify the most recent advances related to safe and effective performance of thoracentesis.

METHODS

We performed a narrative review with a systematic search of the literature. Two authors independently reviewed search results and selected studies based on relevance to thoracentesis; disagreements were resolved by consensus. Articles were categorized as those related to the pre-, intra- and postprocedural aspects of thoracentesis.

RESULTS

Sixty relevant studies were identified and included. Pre-procedural topics included methods for physician training and maintenance of skills, such as simulation with direct observation. Additionally, pre-procedural topics included the finding that moderate coagulopathies (international normalized ratio less than 3 or a platelet count greater than 25,000/μL) and mechanical ventilation did not increase risk of postprocedural complications. Intraprocedurally, ultrasound use was associated with lower risk of pneumothorax, while pleural manometry can identify a nonexpanding lung and may help reduce risk of re-expansion pulmonary edema. Postprocedurally, studies indicate that routine chest X-ray is unwarranted, because bedside ultrasound can identify pneumothorax.

CONCLUSIONS

While the performance of thoracentesis is not without risk, clinicians can incorporate recent advances into practice to mitigate patient harm and improve effectiveness. Journal of Hospital Medicine 2017;12:266-276.

A recommended method in order to interpret chest x-rays for diagnosing small size pneumothorax

Background:

Pneumothorax can be a both progressive and life threatening disorder. In this survey we evaluated the diagnostic accuracy of a recommended method for the interpretation of chest X-Rays (CXRs) compared to the common method in diagnosis of iatrogenic Pneumothorax in an emergency department.

Materials and Methods:

We conducted a study on 100 CXRs (31 with the diagnosis of small size pneumothorax and 69 normal) of patients who have undergone the upper central venous catheterization. CXRs were interpreted by 5 Emergency Specialists (ESs) and 5 general practitioners (GPs) separately using the conventional and recommended method. Recommended method included a 90 degree rotation against the side of chateterization in addition to using a yellow shield as the background color. Presence of pneumothorax on the CXR was confirmed by a radiologist.

Results:

64.5% of the CXRs with pneumothorax were correctly diagnosed by GPs and 87.7% by ESs with reutine method and 83.2% and 97.4% by recommended method, respectively (P.value<0.001). 96.8% out of all CXRs were correctly diagnosed by GPs and 99.4% by ESs by conventional method and 97.9% by GP and 99.7% by ES was correctly diagnosed using recommended method(P.value<0.001). None of the underlying variables including sex, age, underlying diseases, the side of intervention did not affect on the diagnostic accuracy in either groups (P.value>0.05).

Conclusion:

A significant raise was obtained in the diagnostic accuracy of CXR using the recommended method. This study can be a preliminary study to conduct further investigations in order to enhance the diagnostic accuracy of CXRs.

The diagnosis and management of pleural effusions in the ICU

Pleural effusions are common in critically ill patients. Most effusions in intensive care unit (ICU) patients are of limited clinical significance; however, some are important and require aggressive management. Transudative effusions in the ICU are commonly caused by volume overload, decreased plasma oncotic pressure, and regions of altered pleural pressure attributable to atelectasis and mechanical ventilation. Exudates are sequelae of pulmonary or pleural infection, pulmonary embolism, postsurgical complications, and malignancy. Increases in pleural fluid volume are accommodated principally by chest wall expansion and, to a lesser degree, by lung collapse. Studies in mechanically ventilated patients suggest that pleural fluid drainage can result in improved oxygenation for up to 48 hours, but data on clinical outcomes are limited. Mechanically ventilated patients with pleural effusions should be semirecumbant and treated with higher levels of positive-end expiratory pressure. Rarely, large effusions can cause cardiac tamponade or tension physiology, requiring urgent drainage. Bedside ultrasound is both sensitive and specific for diagnosing pleural effusions in mechanically ventilated patients. Sonographic findings of septation and homogenous echogenicity may suggest an exudative effusion, but definitive diagnosis requires pleural fluid sampling. Thoracentesis should be carried out under ultrasound guidance. Antibiotic regimens for parapneumonic effusions should be based on current pneumonia guidelines, and anaerobic coverage should be included in the case of empyema. Decompression of the pleural space may be necessary to improve respiratory mechanics, as well as to treat complicated effusions. While small-bore catheters inserted under ultrasound guidance may be used for nonseptated effusions, surgical consultation should be sought in cases where this approach fails, or where the effusion appears complex and septated at the outset. Further research is needed to determine the effects of pleural fluid drainage on clinical outcomes in mechanically ventilated patients, to evaluate weaning strategies that include pleural fluid drainage, and to better identify patients in whom pleural effusions are more likely to be infected.

Ultrasound for the Detection of Pleural Effusions and Guidance of the Thoracentesis Procedure

Objective. To review the use of ultrasound for the detection of pleural effusions and guidance of the thoracentesis procedure. Methods. Two clinical cases will be presented in which ultrasound proved beneficial in guiding the diagnosis and management of patients with pleural effusions and respiratory distress. The ultrasound techniques for the evaluation of pleural effusions and performance of the thoracentesis procedure are discussed. A review of the most current literature follows to present the known diagnostic and safety benefits of ultrasound guidance for thoracentesis. Conclusions. Ultrasound improves the diagnostic accuracy for the detection of pleural effusions over standard chest radiographs. Ultrasound can also diagnose a complicated pleural effusion that may be at higher risk for an adverse outcome during a thoracentesis. Optimally, thoracentesis should be performed under direct ultrasound guidance to decrease the complication rate and improve patient safety.