Traumatic Pneumothorax: A Review of Current Diagnostic Practices And Evolving Management

Using chest X-ray to predict tube thoracostomy in traumatic pneumothorax: A single-institution retrospective review

BACKGROUND

Traumatic pneumothorax (PTX) is a common occurrence in thoracic trauma patients, with a majority requiring tube thoracostomy (TT) for management. Recently, the "35-mm" rule has advocated for observation of patients with PTX less than 35 mm on chest computed tomography (CT) scan. This rule has not been examined in chest x-ray (CXR). We hypothesize that a similar size cutoff can be determined in CXR predictive of need for tube thoracostomy.

METHODS

We performed a single-institution retrospective review of patients with traumatic PTX from 2018 to 2022, excluding those who underwent TT prior to CXR. Primary outcomes were size of pneumothorax on CXR and need for TT; secondary outcome was failed observation, defined as TT more than 4 hours after presentation. To determine the size cutoff on CXR to predict TT need, area under the receiver operating curve (AUROC) analyses were performed and Youden's index calculated (significance at p < 0.05). Predictors of failure were calculated using logistic regression.

RESULTS

There were 341 pneumothoraces in 304 patients (94.4% blunt trauma, median injury severity score 14). Of these, 82 (24.0%) had a TT placed within the first 4 hours. Fifty-five of observed patients (21.2%) failed, and these patients had a larger PTX on CXR (8.6 mm [5.0-18.0 mm] vs. 0.0 mm [0.0-2.3 mm] ( p < 0.001)). Chest x-ray PTX size correlated moderately with CT size (r = 0.31, p < 0.001) and was highly predictive of need for TT insertion (AUC 0.75, p < 0.0001), with an optimal size cutoff predicting TT need of 38 mm.

CONCLUSION

Chest x-ray imaging size was predictive of need for TT, with an optimal size cutoff on CXR of 38 mm, approaching the "35-mm rule." In addition to size, failed observation was predicted by presenting lactic acidosis and need for supplemental oxygen. This demonstrates this cutoff should be considered for prospective study in CXR.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level IV.

Minimally invasive management of thoracic trauma: current evidence and guidelines

Minimally invasive procedures are being increasingly proposed for trauma. Injuries to the chest wall and/or lung have historically been managed by drainage with a large bore thoracostomy tube, while cardiac injuries have mandated sternotomy. These treatments are associated with significant patient discomfort. Percutaneous placement of small 'pigtail' catheters was initially designed for drainage of simple pericardial fluid. Their use subsequently expanded to drainage of the pleural cavity. The role of pigtail catheters for primary treatment of traumatic pneumothorax and hemopneumothorax has increased, while their use for pericardial fluid after trauma remains controversial. Pericardial windows have alternatively been purposed as a minimally invasive treatment option for possible hemopericardium. The aim of this article is to review the current evidence and guidelines for minimally invasive management of chest trauma.

Management of Blunt Chest Trauma

Common mechanisms of blunt thoracic injury include motor vehicle collisions and falls. Chest wall injuries include rib fractures and sternal fractures; treatment involves supportive care, multimodal analgesia, and pulmonary toilet. Pneumothorax, hemothorax, and pulmonary contusions are also common and may be managed expectantly or with tube thoracostomy as indicated. Surgical treatment may be considered in select cases. Less common injury patterns include blunt trauma to the tracheobronchial tree, esophagus, diaphragm, heart, or aorta. Operative intervention is more often required to address these injuries.

Successful Needle Aspiration of a Traumatic Pneumothorax: A Case Report and Literature Review

Traumatic pneumothorax (PTX) occurs in up to 50% of patients with severe polytrauma and chest injuries. Patients with a traumatic PTX with clinical signs of tension physiology and hemodynamic instability are typically treated with an urgent decompressive thoracostomy, tube thoracostomy, or needle decompression. There is recent evidence that non-breathless patients with a hemodynamically stable traumatic PTX can be managed conservatively through observation or a percutaneous pigtail catheter. We present here a 52-year-old woman who presented to the emergency department with a 55 mm traumatic PTX. Following aspiration of 1500 mL of air, a clinical improvement was immediately observed, allowing the patient to be discharged shortly thereafter. In hemodynamically stable patients with a post-traumatic PTX, without specific risk factors or oxygen desaturation, observation or simple needle aspiration can be a reasonable approach. Although the recent medical literature supports conservative management of small traumatic PTXs, guidelines are lacking for hemodynamically stable patients with a significantly large PTX. This case report documents our successful experience with needle aspiration in such a setting of large traumatic PTX. We aimed in this article to review the available literature on needle aspiration and conservative treatment of traumatic pneumothorax. A total of 12 studies were selected out of 190 articles on traumatic PTX where conservative treatment and chest tube decompression were compared. Our case report offers a novel contribution by illustrating the successful resolution of a sizable pneumothorax through needle aspiration, suggesting that even a large PTX in a hemodynamically stable patient, without other risk conditions, can be successfully treated conservatively with simple needle aspiration in order to avoid tube thoracostomy complications.

Delayed Pneumothorax Following Bougie-Assisted Nasal Intubation

A 45-year-old male with tongue cancer and obstructive sleep apnea presented for glossectomy and right neck dissection. He underwent a difficult nasal intubation assisted by a bougie and Glidescope. After an otherwise uneventful procedure, the patient was extubated and taken to recovery. Several hours later, he developed increased respirations and decreased oxygen (O2) saturation with decreased air movement on the right side of his chest. A chest X-ray confirmed a right pneumothorax. A chest tube was placed with immediate improvement of O2 saturation and breathing. Pneumothorax was presumably due to trauma from intubation. Although pneumothorax is a potential complication of intubation, it is more likely to occur shortly following intubation instead of hours later. The mechanism is often unknown. Providers must monitor patients throughout the perioperative period for any potential respiratory concerns, especially following a difficult intubation. This will ensure prompt diagnosis and management of any complications and provide an optimal outcome for the patient.

Automated Real-Time Detection of Lung Sliding Using Artificial Intelligence: A Prospective Diagnostic Accuracy Study

BACKGROUND

Rapid evaluation for pneumothorax is a common clinical priority. Although lung ultrasound (LUS) often is used to assess for pneumothorax, its diagnostic accuracy varies based on patient and provider factors. To enhance the performance of LUS for pulmonary pathologic features, artificial intelligence (AI)-assisted imaging has been adopted; however, the diagnostic accuracy of AI-assisted LUS (AI-LUS) deployed in real time to diagnose pneumothorax remains unknown.

RESEARCH QUESTION

In patients with suspected pneumothorax, what is the real-time diagnostic accuracy of AI-LUS to recognize the absence of lung sliding?

STUDY DESIGN AND METHODS

We performed a prospective AI-assisted diagnostic accuracy study of AI-LUS to recognize the absence of lung sliding in a convenience sample of patients with suspected pneumothorax. After calibrating the model parameters and imaging settings for bedside deployment, we prospectively evaluated its diagnostic accuracy for lung sliding compared with a reference standard of expert consensus.

RESULTS

Two hundred forty-one lung sliding evaluations were derived from 62 patients. AI-LUS showed a sensitivity of 0.921 (95% CI, 0.792-0.973), specificity of 0.802 (95% CI, 0.735-0.856), area under the receiver operating characteristic curve of 0.885 (95% CI, 0.828-0.956), and accuracy of 0.824 (95% CI, 0.766-0.870) for the diagnosis of absent lung sliding.

INTERPRETATION

Real-time AI-LUS shows high sensitivity and moderate specificity to identify the absence of lung sliding. Further research to improve model performance and optimize the integration of AI-LUS into existing diagnostic pathways is warranted.

Monitoring of spontaneous pneumothorax using electrical impedance tomography: A case report

Pneumothorax is an emergency in thoracic surgeries and respiratory medicine. A technique is warranted for real-time monitoring of pneumothorax at the bedside so that rapid diagnosis and timely intervention can be achieved. We report herein a case in which electrical impedance tomography (EIT) was employed at the bedside to monitor lung ventilation of a patient with spontaneous pneumothorax during treatment. It was found that the affected side/healthy side ventilation ratio and global inhomogeneity were strongly correlated with the severity of pneumothorax. The use of EIT allowed intuitive observation of the effect of pneumothorax on ventilation, which helped the doctors make immediate diagnosis and intervention. After timely and successful treatment, the patient was discharged. This is the first case reporting a complete therapeutic course of spontaneous pneumothorax assessed with EIT. Our case demonstrated that EIT could monitor regional ventilation loss of the affected side of pneumothorax patients at the bedside, and dynamically assess the treatment effect of pneumothorax, which provides an important imaging basis for clinical pneumothorax treatment.

Interpretation of chest fluoroscopy: the risk of misdiagnosing atelectasis as pneumothorax due to greyscale inversion

Anaesthetists may be required to work in hybrid theatres for procedures using fluoroscopic imaging. Adequate knowledge of fluoroscopic images allows prompt and effective emergency management of complications which arise during procedures. Here, we present a case of severe hypotension and hypoxia occurring shortly after induction of anaesthesia. Atelectasis was mistaken for a pneumothorax due to misinterpretation of fluoroscopic imaging, which demonstrated a dark pleural cavity peripheral to a partially collapsed left lung, leading to an incorrect diagnosis. This case highlights the importance of understanding greyscale inversion in fluoroscopy.

[Benefits and drawbacks of CT scan as a triple rule-out exam in acute chest pain to exclude acute coronary syndrome, pulmonary embolism and aortic dissection]

Chest pain is one of the major causes for admission in the Emergency Room in most countries and one of the principal reasons for urgent consultation with a cardiologist or a general practitioner. After clinical examination and initial biological measurements, substantial patients require further explorations. CT scan allows the search for pulmonary embolism in the early stage of pulmonary arteries iodine contrast exploration. During the same exam at the systemic arterial phase, the search for aortic dissection or coronary artery disease is possible while exploring the later contrast in the aortic artery. This triple rule-out exam allows correct diagnosis in case of acute chest pain with suspected pulmonary embolism, aortic dissection and other acute aortic syndromes or acute coronary syndrome. But X-rays are substantially increased as well as iodine contrast agent quantity while exam quality is globally decreased. Artificial intelligence may play an important role in the development of this protocol.

Tips and Tricks in Thoracic Radiology for Beginners: A Findings-Based Approach

This review has the purpose of illustrating schematically and comprehensively the key concepts for the beginner who approaches chest radiology for the first time. The approach to thoracic imaging may be challenging for the beginner due to the wide spectrum of diseases, their overlap, and the complexity of radiological findings. The first step consists of the proper assessment of the basic imaging findings. This review is divided into three main districts (mediastinum, pleura, focal and diffuse diseases of the lung parenchyma): the main findings will be discussed in a clinical scenario. Radiological tips and tricks, and relative clinical background, will be provided to orient the beginner toward the differential diagnoses of the main thoracic diseases.

The Global Burden of Pleural Diseases

Pleural diseases include a spectrum of disorders broadly categorized into pneumothorax and pleural effusion. They often cause pain, breathlessness, cough, and reduced quality of life. The global burden of diseases reflects regional differences in conditions and exposures associated with pleural disease, such as smoking, pneumonia, tuberculosis, asbestos, cancer, and organ failure. Disease burden in high-income countries is overrepresented given the availability of data and disease burden in lower-income countries is likely underestimated. In the United States, in 2016, there were 42,215 treat-and-discharge visits to the emergency room for pleural diseases and an additional 361,270 hospitalizations, resulting in a national cost of $10.1 billion.

Blood Count-Derived Inflammatory Markers Correlate with Lengthier Hospital Stay and Are Predictors of Pneumothorax Risk in Thoracic Trauma Patients

(1) Background: Trauma is one of the leading causes of death worldwide, with the chest being the third most frequent body part injured after abdominal and head trauma. Identifying and predicting injuries related to the trauma mechanism is the initial step in managing significant thoracic trauma. The purpose of this study is to assess the predictive capabilities of blood count-derived inflammatory markers at admission. (2) Materials and Methods: The current study was designed as an observational, analytical, retrospective cohort study. It included all patients over the age of 18 diagnosed with thoracic trauma, confirmed with a CT scan, and admitted to the Clinical Emergency Hospital of Targu Mureş, Romania. (3) Results: The occurrence of posttraumatic pneumothorax is highly linked to age (p = 0.002), tobacco use (p = 0.01), and obesity (p = 0.01). Furthermore, high values of all hematological ratios, such as the NLR, MLR, PLR, SII, SIRI, and AISI, are directly associated with the occurrence of pneumothorax (p < 0.001). Furthermore, increased values of the NLR, SII, SIRI, and AISI at admission predict a lengthier hospitalization (p = 0.003). (4) Conclusions: Increased neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), systemic inflammatory index (SII), aggregate inflammatory systemic index (AISI), and systemic inflammatory response index (SIRI) levels at admission highly predict the occurrence of pneumothorax, according to our data.

Evidence-Based Pearls

The challenge in caring for patients who sustain traumatic chest injuries centers on their complex needs from high acuity and the potential for multisystem effects and complications. Hemorrhage and respiratory compromise are common sequela of thoracic trauma. Patients must be resuscitated and their injuries managed with the primary goals of restoring cardiopulmonary structural integrity and preventing complications. There are evolving strategies for the management of the thoracic trauma victim including damage control resuscitation and surgery, endovascular repairs, and assessments implementing severity scores to aid in planning interventions.

Thoracic point-of-care ultrasound is an accurate diagnostic modality for clinically significant traumatic pneumothorax

OBJECTIVE

There are conflicting data regarding the accuracy of thoracic point-of-care ultrasound (POCUS) in detecting traumatic pneumothorax (PTX). The purpose of our study was to determine the accuracy of thoracic POCUS performed by emergency physicians for the detection of clinically significant PTX in blunt and penetrating trauma patients.

METHODS

We conducted a retrospective institutional review board-approved study of trauma patients 15 years or older presenting to our urban Level I academic trauma center from December 2021 to June 2022. All study patients were imaged with single-view chest radiography (CXR) and thoracic POCUS. The presence or absence of PTX was determined by multidetector computed tomography (CT) or CXR and ultrasound (US) with tube thoracostomy placement.

RESULTS

A total of 846 patients were included, with 803 (95%) sustaining blunt trauma. POCUS identified 13/15 clinically significant PTXs (defined as ≥35 mm of pleural separation on a blinded overread or placement of a tube thoracostomy prior to CT) with a sensitivity of 87% (95% confidence interval [CI] 58-97), specificity of 100% (95% CI 99-100), positive predictive value of 81% (95% CI 54%-95%), and negative predictive value of 100% (95% CI 99%-100%). The positive likelihood ratio was 484 and the negative likelihood ratio was 0.1. CXR identified eight (53%) clinically significant PTXs, with a sensitivity of 53% (95% CI 27%-78%) and a specificity of 100%, when correlated with the CT. The most common reason for a missed PTX identified on expert-blinded overread was failure to recognize a lung point sign that was present on US.

CONCLUSIONS

Thoracic POCUS accurately identifies the majority of clinically significant PTXs in both blunt and penetrating trauma patients. Common themes for false-negative thoracic US in the expert-blinded overread process identified key gaps in training to inspire US education and medical education research.

Management of pneumothorax with 8.3-French Pigtail Catheter: description of the ultrasound-guided technique and case series

Spontaneous and traumatic pneumothorax are most often treated with chest tube (CT) thoracostomy. However, it appears that small-bore drainage systems have similar success rates with lower complications, pain, and discomfort for the patient. We present the description of the ultrasound-guided technique for pneumothorax drainage with an 8.3-French pigtail catheter (PC) in a case series of 10 patients.

[Safety aspects of prehospital thoracic emergency procedures: Results of a survey among German emergency physicians]

BACKGROUND

The safe indication and performance of thoracic emergency procedures are crucial and potentially lifesaving in prehospital emergency care. This study aims to investigate issues of patient safety and quality assurance of prehospital invasive thoracic interventions. The survey does not represent the actual medical care situation but explores reasons for security concerns among emergency physicians.

METHODS

Using a pre-validated questionnaire, prehospital emergency physicians of three prehospital rescue associations (Zweckverband) in Southwest Saxony, Greifswald, and Vechta, Germany, were queried via the online survey service limesurvey. The survey was conducted between January and March 2022.

RESULTS

104 emergency physicians participated (response rate 42.4%) 71 of which fully completed the survey (68%). 79% of the participants stated that they felt safe in performing pleural punction. Common reasons for postponing prehospital thoracic interventions included fear of complications or individual patient characteristics. 90% said that they were familiar with the on-board equipment options, and 60% reported that resources were sufficient to perform double-sided procedures. While in all three regions there is sufficient on-board equipment to perform procedures on two sides, one out of two participants said that lack of equipment deters them from performing prehospital invasive thoracic procedures. Emergency physicians who graduated from trauma courses and/or participate in air rescue are more likely to perform invasive thoracic procedures. More than half of the participants wanted more training in chest tube placement or pleural punction.

CONCLUSION

Safety in prehospital invasive thoracic procedures needs improvement in structural, procedural, as well as human factors aspects. Safe handling of these rare but vital techniques requires more training. A lack of knowledge of equipment is a significant safety gap. Prehospital ultrasound constitutes a structural element of prehospital diagnostics.

Endpoints in Vital Signs as a Useful Tool for Measuring Successful Needle Decompression After Traumatic Tension Pneumothorax: An Analysis of the National Emergency Medicine Information System Database

Background Needle decompression is a useful tool in the pre-hospital setting for treating tension pneumothorax. However the specific improvements in vital signs that determine a successful decompression are only reported in a few studies and Emergency Medical Services (EMS) self-reported assessments of improvement are more commonplace. We hypothesize that EMS reports may exaggerate improvement when compared to objective vital sign changes. Methodology This is a retrospective cohort study using the National Emergency Medicine Information System (NEMSIS) for the year 2020. Vital signs recorded as objective endpoints include systolic blood pressure (SBP), pulse (HR), respiratory rate (RR), and oxygen saturation (SpO₂). Univariate analysis was performed using the t-test for continuous variables and the chi-square test for categorical variables. Results A total of 8,219 calls were included in the sample size analyzed. Most patients were white (2,911, 35.4%) and male (6,694, 81.4%). Abnormal vitals recorded as indications for needle decompression included SBP <100 mmHg, HR <60 or >100 beats/minute, RR <12 or >20 breaths/minute, and SpO₂ <93%. Statistically significant improvements were seen in the number of abnormal vital signs after the procedure. The percentage of improvement was higher in the EMS self-reported assessment than in objective findings for oxygen saturation and SBP. Conclusions Our analysis shows objective improvement of hypoxia and hypotension after field needle decompression, supporting the efficacy of the procedure. The improvement based on vital sign change is modest and is less than that reported by EMS assessment of global improvement. This represents a target for quality improvement in EMS practice.

Chest Tube Placement in Mechanically Ventilated Trauma Patients: Differences between Computed Tomography-Based Indication and Clinical Decision

The rate of occult pneumothorax in intubated and mechanically ventilated trauma patients until initial computed tomography (CT) remains undetermined. The primary aims of this study were to analyze initial chest CTs with respect to the thoracic pathology of trauma, the clinical injury severity, and chest tube placement (CTP) before and after CT. In a single-center retrospective analysis of 616 intubated and mechanically ventilated adult patients admitted directly from the scene to the emergency department (ED), 224 underwent CTP (36%). Of these, 142 patients (62%) underwent CTP before CT, of which, 125 (88%) had significant chest injury on CT. Seventeen patients had minor or absent chest injuries, most of which were associated with transient or unrecognized tracheal tube malposition. After CT, CTP was performed in another 82 patients, of which, 56 (68.3%) had relevant pneumothorax and 26 had minor findings on CT. Sixty patients who had already undergone CTP before CT received another CTP after CT, of which, 15 (25%) had relevant pneumothorax and 45 (75%) had functionality issues or malposition requiring replacement. Nine patients showed small pneumothorax on CT, and did not undergo CTP (including four patients with CTP before CT). The physiological variables were unspecific, and the trauma scores were dependent on the CT findings for identifying patients at risk for CTP. In conclusion, the clinical decisions for CTP before CT are associated with relevant false-negative and false-positive cases. Clinical assessment and CT imaging, together, are important indicators for CTP decisions that cannot be achieved by using clinical assessment or CT alone.

Pneumothorax Following Breast Surgery at an Ambulatory Surgery Center

Pneumothorax is a known complication following breast surgery but is likely underappreciated by anesthesiologists. Iatrogenic pneumothorax can be caused by needle injury during local anesthetic injection, surgical damage to the intercostal fascia or pleura, or pulmonary injury from mechanical ventilation. We present two cases of pneumothorax following bilateral mastectomy with bilateral pectoral blocks and immediate breast reconstruction. Both cases occurred at a freestanding ambulatory surgery center in patients with no history of lung disease. One patient was found to have bilateral pneumothoraxes after complaining of shortness of breath and chest pain in the post-operative care unit. The second patient was asymptomatic but found to have a right-sided pneumothorax on a chest X-ray (CXR) that was ordered to rule-out left-sided pneumothorax due to concern of intraoperative breach of the left chest wall. Both patients were treated with chest tubes, transferred to a nearby hospital, and discharged several days later. Anesthesiologists must be aware of this potentially life-threatening complication and consider pneumothorax in the differential diagnosis of perioperative hypoxemia, shortness of breath, chest pain, and hemodynamic collapse in patients undergoing breast surgery. Though traditionally diagnosed via radiograph, pneumothorax can be rapidly diagnosed with ultrasound. Tension pneumothorax should be decompressed immediately with a needle. A clinically significant, non-tension pneumothorax is treated with chest tube placement. Equipment necessary to treat pneumothorax should be available for emergency treatment in facilities wherever breast surgery is performed.