Diagnosis and treatment of patients with spontaneous pneumomediastinum. Respir Investig. 2014;52:36-40. [PMID: 24388369 DOI: 10.1016/j.resinv.2013.06.001]

The Macklin Effect: An Underestimated Cause of Pneumomediastinum

The Macklin effect is a rare but potentially serious complication of pneumomediastinum, caused by the dissemination of air from the lungs into the subcutaneous tissue and mediastinum after severe chest trauma or invasive manipulation. Early recognition is crucial for proper management of the patient. A 33-year-old male skidded while riding a motorcycle, lost control of the vehicle, and crashed into a utility pole with a thoracic contusion. He was admitted to the hospital; a computed tomography (CT) of the chest and abdomen was requested, which ruled out the presence of fractures and showed air in the mediastinum and subcutaneous cellular tissue, with features suggestive of the Macklin phenomenon. After 72 hours of inpatient monitoring, the patient was discharged to the general surgery outpatient clinic. The Macklin phenomenon occurs as a result of airway rupture due to negative pressure caused by trauma or invasive mechanical ventilation. Risk factors include a higher prevalence in young males, a slender stature and above-average height, and an age range of 12 to 35 years. Early detection of the Macklin phenomenon is crucial to recognize and prevent further complications. This case demonstrated the importance of considering the Macklin effect as a cause of pneumomediastinum in patients with severe chest trauma. Diagnostic imaging plays a key role in confirming the diagnosis and planning treatment.

Spontaneous pneumomediastinum: A comprehensive review of diagnosis and management

Pneumomediastinum is a rare condition defined by the presence of air in the mediastinum. In the absence of traumatic injury, iatrogenic injury, or clear etiology, it is called spontaneous pneumomediastinum (SPM). Spontaneous pneumomediastinum most commonly occurs in younger individuals and has a self-limiting course with a good outcome. The purpose of the present manuscript is to systematically review the existing literature on SPM evaluation and management for updated clinical understanding of this condition. A literature search was conducted of publications about SPM on MEDLINE/PubMed and Google Scholar by identifying all the articles with key search terms "pneumomediastinum" and "spontaneous pneumomediastinum". Inclusion criteria were case series published in English between 1980 and 2023. In total, 24 case series were selected and reviewed to determine presenting symptoms, clinical signs and predisposing factors associated with spontaneous pneumomediastinum. Most patients were male; the average age at diagnosis was 26.3 years. The most common presenting symptoms were chest pain and dyspnea. The most common exam finding was subcutaneous emphysema, in 35.4% of patients. Only 5.9% had the classic Hamman's sign. Risk factors include history of asthma, history of smoking, and recent physical activity. This manuscript presents an extensive review of relevant literature highlighting the diagnosis and essential management of spontaneous pneumomediastinum.

Laryngotracheal trauma-induced Macklin effect: A case report

Laryngotracheal trauma is a relatively rare traumatic injury seen particularly in young male adults. Trauma due to strangulation is one of its most frequent circumstances. However rare, pneumomediastinum is a particular complication of severe blunt neck injuries leading to alveolar ruptures. This phenomenon, described as the Macklin effect, requires early diagnosis, and its management varies from conservative to surgical treatment depending on the severity of symptoms. Our aim is to describe the case of a 21-year-old male who presented with blunt neck trauma. Clinical and imaging findings revealed subcutaneous neck emphysema and pneumomediastinum. Treatment was conservative leading to complete resolution of the injuries and the patient was discharged after 2 weeks.

Secondary pneumomediastinum in COVID-19 patient: A case managed with VV-ECMO

Air leak syndrome, including pneumomediastinum (PM), pneumopericardium, pneumothorax, or subcutaneous emphysema, is primarily caused by chest trauma, cardiothoracic surgery, esophageal perforation, and mechanical ventilation. Secondary pneumomediastinum (SP) is a rare complication, with a much lower incidence reported in patients with coronavirus disease 2019 (COVID-19). Our patient was a 44-year-old nonsmoker male with a previous history of obesity (Body Mass Index [BMI] 35 kg/m2), hyperthyroidism, hypokinetic cardiopathy and atrial fibrillation in treatment with flecainide, who presented to the emergency department with 6 days of fever, cough, dyspnea, and respiratory distress. The COVID-19 diagnosis was confirmed based on a polymerase chain reaction (PCR) test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). After initiation of mechanical ventilation, a chest computed tomography (CT) on the first day revealed bilateral multifocal ground-glass opacities, consolidation and an extensive SP and pneumoperitoneum. Our therapeutic strategy was initiation of veno-venous extracorporeal membrane oxygenation (VV-ECMO) as a bridge to recovery after positioning 2 drains (mediastinal and pleural), for both oxygenation and carbon dioxide clearance, to allow protective and ultra-protective ventilation to limit ventilator-induced lung injury (VILI) and the intensity of mechanical power for lung recovery. After another chest CT scan which showed a clear reduction of the PM, 2 pronation and neuromuscular relaxation cycles were also required, with improvement of gas exchange and respiratory mechanics. On the 15th day, lung function recovered and the patient was then weaned from VV-ECMO, and ultimately made a good recovery and was discharged. In conclusion, SP may be a reflection of extensive alveolar damage and should be considered as a potential predictive factor for adverse outcome in critically ill SARS-CoV2 patients.

Primary spontaneous pneumomediastinum: 237 cases in a single-center experience over a 10-year period and assessment of factors related with recurrence

OBJECTIVE

To evaluate the precipitating factors and symptoms of primary spontaneous pneumomediastinum (PSPM) and to assess the factors related with recurrent spontaneous pneumomediastinum (RSPM).

METHODS

From 2010 to 2021, 237 PSPM patients were included in this retrospective study. Clinical information including in-hospital periods, morbidity, mortality, presenting symptoms, precipitating events, smoking, and asthma history was obtained. The patients with smoking history were subdivided into "ex-smoker" or "current smoker". The severity of asthma was categorized into "mild intermittent", "mild persistent", "moderate persistent", or "severe persistent". During follow-up, patients with RSPM were classified into "recurrence" group and the others were into "no recurrence" group. Multivariate regression analysis was used to elucidate the associated factors with RSPM.

RESULTS

The mean age of study patients (men: women = 222: 15) was 23.4 years and mean period of hospital stay was 7.5 days. There was no mortality and morbidity. Most frequent symptom and precipitating factor were acute chest pain (n = 211, 89.0%) and cough (n = 72, 30.4%), respectively. RSPM occurred in 11 patients (4.6%). The proportion of patients with smoking (72.8% vs. 37.1%, p = 0.010) or asthma (81.8% vs. 39.8%, p<0.001) was significantly higher in "recurrence" group than "no recurrence" group. On multivariate analysis, asthma was the only factor associated with RSPM (mild intermittent/persistent, OR = 7.092, p = 0.047; moderate persistent, OR = 8.000, p = 0.011).

CONCLUSION

PSPM is a benign disease with no morbidity and mortality. Asthma may be the associated factor with RSPM; thus, despite the low rate of recurrence, patients with asthma should be informed about the chance of RSPM.

Clinical use of Macklin-like radiological sign (Macklin effect): A systematic review

INTRODUCTION

Recent studies suggested that Macklin sign is a predictor of barotrauma in patients with acute respiratory distress syndrome (ARDS). We performed a systematic review to further characterize the clinical role of Macklin.

METHODS

PubMed, Scopus, Cochrane Central Register and Embase were searched for studies reporting data on Macklin. Studies without data on chest CT, pediatric studies, non-human and cadaver studies, case reports and series including <5 patients were excluded. The primary objective was to assess the number of patients with Macklin sign and barotrauma. Secondary objectives were: occurrence of Macklin in different populations, clinical use of Macklin, prognostic impact of Macklin.

RESULTS

Seven studies enrolling 979 patients were included. Macklin was present in 4-22% of COVID-19 patients. It was associated with barotrauma in 124/138 (89.8%) of cases. Macklin sign preceded barotrauma in 65/69 cases (94.2%) 3-8 days in advance. Four studies used Macklin as pathophysiological explanation for barotrauma, two studies as a predictor of barotrauma and one as a decision-making tool. Two studies suggested that Macklin is a strong predictor of barotrauma in ARDS patients and one study used Macklin sign to candidate high-risk ARDS patients to awake extracorporeal membrane oxygenation (ECMO). A possible correlation between Macklin and worse prognosis was suggested in two studies on COVID-19 and blunt chest trauma.

CONCLUSIONS

Increasing evidence suggests that Macklin sign anticipate barotrauma in patients with ARDS and there are initial reports on use of Macklin as a decision-making tool. Further studies investigating the role of Macklin sign in ARDS are justified.

Point-of-Care Ultrasonography Helped to Rapidly Detect Pneumomediastinum in a Vomiting Female

Vomiting-induced pneumomediastinum is a rare presentation and can be a result of alveolar rupture (Mackler effect) or Boerhaave syndrome. Patients diagnosed with Boerhaave syndrome may present with the classic Mackler triad of vomiting, chest pain, and subcutaneous emphysema. However, there exists a large overlap of symptoms accompanying Boerhaave syndrome and the Macklin effect, including retrosternal chest pain, neck discomfort, cough, sore throat, dysphagia, dysphonia, and dyspnea. Boerhaave syndrome is a dangerous condition. Delayed diagnosis of Boerhaave syndrome may worsen sepsis and cause mortality. Therefore, early diagnosis and timely management are important to prevent further complications. Here, we present a case of vomiting-induced pneumomediastinum, which supports the use of bedside ultrasonography to aid in the diagnosis and rapid differentiation of etiology of pneumomediastinum.

Four Different Reasons of Subcutaneous Emphysema With or Without Pneumomediastinum and Pneumothorax After Facial Bone Surgery

ABSTRACT

In the present study, the authors report rare case series with subcutaneous emphysema with or without pneumomediastinum and pneumothorax after orthognathic and facial bone contouring surgery, compare their clinical and radiologic findings, and suggest precautions. Four patients who showed subcutaneous emphysema on follow up chest X-ray and computed tomography after orthognathic and facial bone contouring surgery were included in the study. In all cases post-op subcutaneous emphysema were detected, however, the aspect and mechanisms of post-op air spread were all different. After the conservative management with administering the O2 by nasal cannula or endotracheal tube, the symptoms were relieved except 1 patient who needed chest tube insertion and further supra-sternal incision. In conclusion, subcutaneous emphysema with or without pneumomediastinum and pneumothorax after orthognathic and facial bone contouring surgery can be occurred by cervical fascia injury or alveolar ruptures. To preventing those complications, traumatic naso-tracheal intubation, excessive positive pressure ventilation, intermaxillary fixation immediate after the surgery, and increase of intra-alveolar pressure of the patients should be avoided.

A Rare Complication during Vaginal Delivery, Hamman's Syndrome: A Case Report and Systematic Review of Case Reports

Background: Spontaneous pneumomediastinum (SPM) during pregnancy or labor is a rare event. We presented a case report and a systematic review of the literature to provide comprehensive symptoms, treatments, and complications analysis in the pregnant population affected by SPM. Methods: We conducted a comprehensive search of four databases for published papers in all languages from the beginning to 1 September 2021; Results: We included 76 papers with a total of 80 patients. A total of 76% patients were young primiparous, with a median age of 24 ± 5.4 years. The median gestational age was 40 ± 2.4 weeks, with a median duration of labor of 7.4 ± 4.2 h. In 86%, the ethnic origin was not specified. SPM develops in 55% of cases during the second stage of labor. Subcutaneous swelling and subcutaneous emphysema were present in 91.4%. Chest pain and dyspnea were present in 51.4% and 50% of the patients, respectively. We found that 32.9% patients had crepitus, and less common symptoms were dysphonia and tachycardia (14.3% and 14.3%, respectively). Oxygen and bronchodilators were used in 37.7% of the cases. Analgesics or sedatives were administered in 27.1%. Conservative management or the observation was performed in 21.4% and 28.6%, respectively. Antibiotics treatment was offered in 14.3%, whereas invasive procedures such as chest-tube drainage were used in just 5.7% of patients. There were no complications documented in most SPM (70.0%). We found that 16.7% of the SPM developed a pneumothorax and 5% developed a pneumopericardium.; Conclusions: In pregnancy, SPM occurs as subcutaneous swelling or emphysema during the second stage of labor. The treatment is usually conservative, with oxygen and bronchodilators and a low sequela rate. A universal consensus on therapy of spontaneous pneumomediastinum in pregnancy is necessary to reduce the risk of complications.

[SARS-CoV-2-associated pneumothorax, pneumomediastinum and soft tissue emphysema. Clinical implications based on a case series]

The new coronavirus (SARS-CoV-2) that arose in 2019 causes a wide spectrum of symptoms and different courses of disease. Pneumothorax, pneumomediastinum and soft tissue emphysema are rare complications in patients with pulmonary involvement. They are the sequelae of severe, virus-induced structural changes of the pulmonary architecture. High pressure artificial ventilation aggravates the problem. Hence pneumothorax and ectopic air in soft tissues are indicators of extensive pulmonary damage. Therefore, efforts should be made to treat even very small or multiply recurrent pneumothorax by drainage procedures.

A radiological predictor for pneumomediastinum/pneumothorax in COVID-19 ARDS patients

Purpose

To determine whether Macklin effect (a linear collection of air contiguous to the bronchovascular sheath) on baseline CT imaging is an accurate predictor for subsequent pneumomediastinum (PMD)/pneumothorax (PNX) development in invasively ventilated patients with COVID-19-related acute respiratory distress syndrome (ARDS).

Materials and methods

This is an observational, case-control study. From a prospectively acquired database, all consecutive invasively ventilated COVID-19 ARDS patients who underwent at least one baseline chest CT scan during the study time period (February 25th, 2020–December 31st, 2020) were identified; those who had tracheal lesion or already had PMD/PNX at the time of the first available chest imaging were excluded.

Results

37/173 (21.4%) patients enrolled had PMD/PNX; specifically, 20 (11.5%) had PMD, 10 (5.8%) PNX, 7 (4%) both. 33/37 patients with subsequent PMD/PNX had Macklin effect on baseline CT (89.2%, true positives) 8.5 days [range, 1–18] before the first actual radiological evidence of PMD/PNX. Conversely, 6/136 patients without PMD/PNX (4.4%, false positives) demonstrated Macklin effect (p < 0.001). Macklin effect yielded a sensitivity of 89.2% (95% confidence interval [CI]: 74.6–96.9), a specificity of 95.6% (95% CI: 90.6–98.4), a positive predictive value (PV) of 84.5% (95% CI: 71.3–92.3), a negative PV of 97.1% (95% CI: 74.6–96.9) and an accuracy of 94.2% (95% CI: 89.6–97.2) in predicting PMD/PNX (AUC:0.924).

Conclusions

Macklin effect accurately predicts, 8.5 days in advance, PMD/PNX development in COVID-19 ARDS patients.

A narrative review of primary spontaneous pneumomediastinum: a poorly understood and resource-intensive problem

Primary spontaneous pneumomediastinum (PSPM) is a benign self-limited condition that can be difficult to discriminate from esophageal perforation. This may trigger costly work-up, transfers and hospital admissions. To better understand this diagnostic dilemma and current management, we undertook the most comprehensive and up to date review of PSPM. The PubMed database was searched using the MeSH term "Mediastinal Emphysema"[Mesh], to identify randomized controlled trials, meta-analyses and case series (including 10 or more patients) relevant to the clinical presentation and management of patients with PSPM. There were no relevant randomized controlled trials or meta-analyses. Nineteen case series met our criteria, including a total of 535 patients. The average mean age was 23 years with a 3:1 male predominance. Chest pain was the most common symptom, found in 70.9% of the patients. Dyspnea and neck pain were the second and third most common symptoms, found in 43.4% and 32% of the patients, respectively. Subcutaneous emphysema was the most common sign (54.2%). Common histories included smoking (29.6%), cough (27.7%), asthma (25.9%), physical exertion (21.1%) and recent retching or emesis (13%). Nearly all patients (96.9%) underwent chest X-ray (CXR). Other diagnostic studies included computed tomography (65%) and esophagram (35.6%). Invasive studies were common, with 13% of patients undergoing esophagogastroduodenoscopy and 14.6% undergoing bronchoscopy. The rate of hospital admission was 86.5%, with an average length of stay of 4.4 days. No deaths were reported. Notably, we identified a dearth of information regarding the vitals, laboratory values and imaging findings specific to patients presenting with PSPM. We conclude that PSPM is a benign clinical entity that continues to present a resource-intensive diagnostic challenge and that data on the vitals, labs, and imaging findings specific to PSPM patients is scant. An improved understanding of these factors may lead to more efficient diagnosis and management of these patients.

Pneumomediastinum in COVID-19 disease: Outcomes and relation to the Macklin effect

AIM

Pneumomediastinum (PM) is associated with several etiologies and mechanisms. Although it has been described more than 100 years ago, the literature is limited to small retrospective studies. This study aimed to follow patients with coronavirus disease (COVID-19) that developed PM during hospitalization and describe their clinical and radiological evolution.

METHODS

A prospective cohort was developed with patients with PM, excluding those with aerodigestive trauma, inside a hospital COVID-19 dedicated hospital. Clinical variables including onset of symptoms, hemodynamic instability, associated complications, the need of interventions, and disease course were all recorded. Also, radiological findings such as the presence of the Macklin effect, extension of lung involvement by COVID-19, and characteristics of the PM were analyzed.

RESULTS

Twenty-one patients with non-traumatic PM were followed, resulting in an overall incidence of 0.5% during the study period. Seven (33%) patients had associated pneumothorax and malignant/tension PM was observed in three (14%) cases. The Macklin effect could be found in 11 patients (52%) and the majority of them had more than 50% of lung involvement due to COVID-19. The mortality rate was 49%; however, no deaths were directly related to the PM.

CONCLUSIONS

PM incidence is probably increased in the severe acute respiratory syndrome caused by COVID-19, especially in those with greater involvement of the lungs, and the Macklin effect may be an important underlying mechanism of this complication. Usually, PM has a benign course, but complications like tension/malignant PM may occur requiring prompt detection and intervention.

Clinical analysis of 71 spontaneous pneumomediastinum cases: an observational study from a tertiary care hospital in Japan

BACKGROUND

Spontaneous pneumomediastinum is characterized by the presence of interstitial air in the mediastinum without any underlying disease. Some cases of spontaneous pneumomediastinum have been reported in the past, although only few reports are available, and its management remains uncertain. This study reviewed our experience in the diagnosis and treatment of spontaneous pneumomediastinum.

METHODS

A retrospective study of 71 cases treated for spontaneous pneumomediastinum at the Yodogawa Christian Hospital between April 2005 and March 2020 was conducted.

RESULTS

The patients' mean age was 19.3 years (range, 7-48 years). A triggering event was noted in 69% of the cases. Seventy-six percent of the patients were admitted to the hospital, and 24% were outpatients. Treatment included analgesia, rest, antibiotics, and/or oxygen therapy. Thirty-six patients (51%) were treated with antibiotics. None of the cases presented any complications, including mediastinitis or worsening respiratory condition. Two patients (3%) had a recurrence of spontaneous pneumomediastinum.

CONCLUSIONS

All the patients, with or without antimicrobial treatment and hospitalization, had favorable outcomes. We should therefore reconsider the need for hospitalization and antimicrobial therapy for patients with mediastinitis prophylaxis.

Pneumomediastinum following intubation in COVID-19 patients: a case series

The number of patients requiring tracheal intubation rose dramatically in March and April 2020 with the COVID-19 outbreak. Our thoracic surgery department has seen an increased incidence of severe pneumomediastinum referred for surgical opinion in intubated patients with COVID-19 pneumonitis. Here we present a series of five patients with severe pneumomediastinum requiring decompression therapy over a 7-day period in the current COVID-19 outbreak. We hypothesise that the mechanism for this is the aggressive disease pathophysiology with an increased risk of alveolar damage and tracheobronchial injury, along with the use of larger-bore tracheal tubes and higher ventilation pressures. We present this case series in order to highlight the increased risk of this potentially life-threatening complication among the COVID-19 patient cohort and offer guidance for its management to critical care physicians.

Noninvasive positive pressure ventilator deteriorates the outcome of pneumomediastinum in anti-MDA5 antibody-positive clinically amyopathic dermatomyositis

BACKGROUND

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody (Ab)-positive clinically amyopathic dermatomyositis (CADM) with pneumomediastinum (PNM) is a life-threatening condition. We aim to determine the prognostic factors affecting survival of patients with anti-MDA5 Ab-positive CADM complicated with PNM.

METHODS

We retrospectively established a cohort of patients with anti-MDA5 Ab-positive CADM complicated with PNM from April 2013 to July 2019. Demographic data and clinical characteristics from medical records were analyzed and variables were compared between survivors and nonsurvivors. We performed univariate and multivariate survival analyses by Cox regression. Survival curves were depicted by the Kaplan-Meier method.

RESULTS

Among 133 patients with anti-MDA5 Ab-positive CADM, 20 were diagnosed with PNM. The cumulative estimated Kaplan-Meier survival rate was 85% at 1 week, 55% at 1 month, and 40% at 1 year. Univariate analysis indicated several factors associated with survival. Worse liver function (AST, p = 0.043; LDH, p = 0.002; TBIL, p = 0.038), higher CRP level (p = 0.044), higher HRCT score (p = 0.022), and using noninvasive positive pressure ventilation (NPPV) (p < 0.01) were associated with poor prognosis. In a multivariate Cox regression model, AST level and using NPPV were indicated to be independent predictors of poor prognosis.

CONCLUSION

In this research, we found that the incidence rate of PNM in anti-MDA5 Ab-positive CADM was 15.5%, obviously higher than in classical DM. The application of noninvasive positive pressure ventilator (NPPV) and higher AST level were independent risk factors for survival.Key Points• Anti-MDA5 Ab-positive CADM complicated with PNM is a life-threatening condition with an incidence rate of 15.5%.• The application of NPPV and worse liver function were independent risk factors for survival of anti-MDA5 Ab-positive CADM patients complicated with PNM.

Pneumomediastinum revisited: we should reconsider usual classification

Pneumomediastinum work-up should focus on differentiating mediastinal organ injuries from alveolar rupture since these two causative mechanisms have a different management and prognosis. After an admission at our Emergency Department, we wanted to challenge the current classification into 'spontaneous' or 'secondary' pneumomediastinum, which reflects the clinical rather than the pathophysiological circumstances and is therefore confusing and inappropriate to our view. We propose a new work-up algorithm based on clinical risks factors and chest CT findings.

The Value of Different Radiological Modalities in Assessment of Spontaneous Pneumomediastinum: Case Review and Diagnostic Perspective

Pneumomediastinum (PM), or a mediastinal air leak, is a known morbidity in neonates. Among predisposing factors, the most significant are mixed lung diseases, such as pneumonia or meconium aspiration syndrome, with coexisting atelectasis and airway obstruction. We report an unusual presentation of significant spontaneous pneumomediastinum in a term newborn delivered by elective cesarean section with no history of active resuscitation at birth. Timely diagnosis of SPM is important for both management and prognosis. We believe that lung ultrasound (LUS) is a promising screening tool for early detection of PM in neonates, and could help avoid unnecessary exposure to radiation in delicate neonates. More simultaneous studies comparing chest X-ray (CXR), LUS, and computed tomography (CT) scans may help to prove the utility value of point-of-care ultrasounds as a primary diagnostic tool in identifying this morbidity.

Spontaneous pneumomediastinum: Case presentation to a college student health clinic

The author describes a case of spontaneous pneumomediastinum (SPM) in a 19-year-old man presenting to a college student health clinic. The author also provides a review on SPM, including clinical manifestations, diagnostic evaluation, and management.

Pneumomediastinum: An unusual complication after percutaneous nephrolithotomy

Pneumomediastinum is the presence of air within the mediastinum. It is usually caused by a respiratory tract disorder, esophageal erosion, bowel perforation, or gastrointestinal tract endoscopic procedure. Pneumomediastinum following urological endoscopic surgery is very uncommon. Here, we report an unusual case of pneumomediastinum in a 55-year-old female following percutaneous nephrolithotomy for renal and ureteral stones. The patient recovered well with supportive treatment with oxygen.

Pediatric Spontaneous Pneumomediastinum: Narrative Literature Review

INTRODUCTION

Described since 1939 in the adult population, spontaneous pneumomediastinum is less known in children. Because of its symptoms and a generally benign evolution, it is probably an underestimated diagnosis. However, it has to be considered in the differential diagnosis of acute thoracic pain.

METHODS

The incidence being low, we conducted a narrative literature review to identify the circumstances leading to a spontaneous pneumomediastinum, the most relevant signs and symptoms, investigations, as well as treatment recommendations.

RESULTS

Of 216 patients, 66.2% are boys, and mean ages range from 6.9 to 14 years. The most frequent comorbidity in children is asthma (22.2%), and the most common trigger factors are bronchospasm (49%), cough (45.6%), various respiratory tract infections, vomiting (10.3%), and foreign body aspiration (8.3%). It remains idiopathic in 33.3%. Relevant signs are chest pain (54.6%), neck pain and/or sore throat (53.3%), and dyspnea (41.2%). The most relevant sign is palpation of subcutaneous emphysema (66.4%). The classically described Hamman crunch is only present in 11.6%. Chest x-ray provides the right diagnosis in 99.5% of the patients. Pneumothorax is associated in 11.6%. Most patients are hospitalized (88.3%); treatment is based on oxygen therapy, painkillers, and rest. In some series, there can be up to 25.8% of patients requiring intensive care and 5.5% requiring drainage of associated pneumothorax. Survival rate is 92.5%, and long-term follow-up shows normal x-rays after 4 days and no recurrence.

CONCLUSIONS

Spontaneous pneumomediastinum is uncommon in children but must be considered in pediatric patients with acute chest and/or neck pain. History taking, physical examination, and standard chest x-ray are most often diagnostic, and there is rarely a need for other investigation.Hospitalization is not always indispensable; ambulatory management can be considered. Outcome is good, and follow-up can be clinical, therefore avoiding further x-rays.

Spontaneous pneumomediastinum in a healthy young female: A case report and literature review

Spontaneous pneumomediastinum (SPM) is an uncommon finding in young adults presenting usually without any comorbidities or an underlying pathology. It is most commonly due to alveolar rupture in the setting of an inciting event such an underlying asthma, barotrauma, valsalva maneuver, or esophageal rupture. Individuals can have varying presentations, from chest pain, dyspnea and dysphagia, to anxiety, weakness, or facial and neck swelling. The majority of patients have subcutaneous emphysema on examination and can have abnormal laboratory findings such as an elevated C-reactive proteins and leukocytosis. Diagnostic modalities used include chest x-ray, CT scan, ultrasound and barium swallow or esophagram. Majority of individuals and treated conservatively with rest, analgesia and oxygen administration. The prognosis of SPM is usually good with resolution within several days in most cases and the recurrence rate is very low. We report the case of a 22-year-old female presented with SPM diagnosed by chest x-ray and chest CT scan who was treated conservatively with subsequent spontaneous resolution.

The Effective Treatment with Cyclosporine of a Ulcerative Colitis Patient with Concurrent Idiopathic Thrombocytopenic Purpura Who Subsequently Developed Spontaneous Pneumomediastinum

Although extraintestinal manifestations of inflammatory bowel diseases are not uncommon, few reports have described concurrent idiopathic thrombocytopenic purpura (ITP). Spontaneous pneumomediastinum is also a rare complication of ulcerative colitis (UC). This report describes the case of a 14-year-old boy who experienced recurrent ulcerative colitis 3 months after temporary improvement following treatment with prednisolone (20 mg/day) and granulocyte/monocyte adsorption apheresis. His platelet counts decreased, suggesting ITP. The dosage of prednisolone was increased to 60 mg/day; however, his thrombocytopenia did not improve and he suddenly developed pneumomediastinum. A continuous infusion of cyclosporine increased his platelet counts and improved his ulcerative colitis. Cyclosporine should be considered when steroid-resistant ITP accompanies UC.

[Not Available]

Zusammenfassung. Bei 6–8 % der jungen Erwachsenen sind Thoraxschmerzen Anlass für eine notfallmässige Konsultation. Thoraxschmerzen sind bei jungen Patienten meist unspezifisch, in der Regel benigner Ätiologie und ohne vitale Bedrohung. Wir berichten von einem 16-jährigen Patienten mit thorakalen Schmerzen nach sportlicher Tätigkeit. Radiologisch zeigte sich freie Luft im Mediastinum ohne begleitenden Pneumothorax oder mediastinale Organpathologie. Nachfolgend konnte die Diagnose eines spontanen Pneumomediastinums (PM) gestellt werden. Das spontane oder primäre PM ist eine seltene klinische Entität, die ohne Therapie selbstlimitierend ist. Essenziell ist dabei die Differenzierung vom sekundären PM, dem gefährliche Organläsionen zugrundeliegen und das unbehandelt mit einer hohen Mortalität einhergeht.

Presence of subpleural pulmonary interstitial emphysema as an indication of single or multiple alveolar ruptures on CT in patients with spontaneous pneumomediastinum

Background There are no previous reports regarding the computed tomography (CT) findings of subpleural pulmonary interstitial emphysema (PIE) in patients with spontaneous pneumomediastinum. Purpose To evaluate CT findings of subpleural PIE that may indicate a direct site of terminal alveolar rupture. Material and Methods We retrospectively evaluated chest CT and the medical records of 34 patients with spontaneous pneumomediastinum. Subpleural PIE was defined as the presence of an interstitial air collection in the subpleural portion of the lungs excluding the bronchovascular bundle. Results Subpleural PIE on CT was identified in six of 34 patients (17.6%) with spontaneous pneumomediastinum. In four of these (66.7%), subpleural PIE was present in multiple lobes suggesting multiple simultaneous ruptures of terminal alveoli. The shape of subpleural PIE was elongated linear (4/6), branching and linear (1/6), and elliptical (1/6). Conclusion The presence of subpleural PIE on CT suggests an origin of pneumomediastinal air from alveolar rupture.

Pneumomediastinum, pneumorrhachis, and subcutaneous emphysema in Pneumocystis jiroveci pneumonia in AIDS

Pneumomediastinum, the presence of free air within the mediastinal cavity, is sometimes accompanied by subcutaneous emphysema and pneumorrhachis (air within the spinal canal). We report the case of a 28-year-old man with previously undiagnosed HIV who was diagnosed with extensive pneumomediastinum, pneumorrhachis, and subcutaneous emphysema secondary to Pneumocystis jiroveci pneumonia after presenting with chest pain, dyspnea, and central cyanosis. Surgical consultation was requested, but a conservative approach of observation proved sufficient as the free air was resorbed into the surrounding tissues.

Unique case of pneumomediastinum due to penetrating injury to the mediastinum

Pneumomediastinum is a rare condition, and mostly occurs following traumatic or iatrogenic tracheal and oesophageal perforation, but spontaneous pneumomediastinum has also been described. We report a case of a 17-year-old woman who presented with a penetrating neck wound after a fall down the stairs. She had an extensive pneumomediastinum without signs of tracheal or oesophageal laceration, rib fractures, pneumothorax or haematothorax. The contaminated wound was surgically explored and extensively lavaged. Prophylactic antibiotic treatment was given and the patient recovered without complications. Direct perforating trauma to the mediastinum is a severe entity, but can be treated by lavage and prophylactic antibiotic therapy.

Spontaneous pneumomediastinum in the pediatric patient

BACKGROUND

Spontaneous pneumomediastinum (SPM) data in children are limited. We investigated the management of SPM at our institution.

METHODS

We reviewed children with pneumomediastinum treated from January 2011 to October 2014. Primary (no precipitating factors) and secondary (underlying respiratory disease) SPM patients were included. Admission data and clinical outcomes were recorded.

RESULTS

A total of 129 patients were included. Average age was 11.6 ± 4.6 years; 90 males (70%). Frequent presenting symptoms were chest pain (n = 76) and dyspnea (n = 51). Of the total, 89 patients (69%) were admitted. No patient required additional interventions. Of those, 85 patients (65.9%) had follow-up. Patients with secondary SPM (n = 58) were more likely than primary (n = 71) to be admitted (84% vs 56%, P = .001), receive oxygen (69% vs 35%, P = .04), and have longer stays (2 days [interquartile range, 1 to 3] vs 1 day [interquartile range, 0 to 1], P < .001). Readmission rates were equivalent.

CONCLUSIONS

Differentiating types of SPM is important as clinical course differs. Secondary SPM patients are more frequently admitted than primary SPM patients.

Spontaneous pneumomediastinum on bedside ultrasound: case report and review of the literature

Spontaneous pneumomediastinum is a rare disease process with no clear etiology, although it is thought to be related to changes in intrathoracic pressure causing chest pain and dyspnea. We present a case of a 17-year-old male with acute chest pain evaluated initially by bedside ultrasound, which showed normal lung sliding but poor visualization of the parasternal and apical cardiac views due to significant air artifact, representing air in the thoracic cavity. The diagnosis was later verified by chest radiograph. We present a case report on ultrasound-diagnosed pneumomediastinum, and we review the diagnostic modalities to date.

Spontaneous pneumomediastinum and Macklin effect: Overview and appearance on computed tomography

Spontaneous pneumomediastinum (SPM) is described as free air or gas located within the mediastinum that is not associated with any noticeable cause such as chest trauma. SPM has been associated with many conditions and triggers, including bronchial asthma, diabetic ketoacidosis, forceful straining during exercise, inhalation of drugs, as well as other activities associated with the Valsalva maneuver. The Macklin effect appears on thoracic computed tomography (CT) as linear collections of air contiguous to the bronchovascular sheaths. With the recent availability of multidetector-row CT, the Macklin effect has been seen in the clinical setting more frequently than expected. The aim of this review article is to describe the CT imaging spectrum of the Macklin effect in patients with SPM, focusing on the common appearance of the Macklin effect, pneumorrhachis, and persistent SPM with pneumatocele.