BACKGROUND: With the prevalence of coronavirus disease 2019 (COVID-19), many severe cases have been discovered worldwide. Here, a case of concurrent pneumomediastinum, pneumoretroperitoneum, and intestinal perforation was reported. This case was the first report on COVID-19-induced related complications.
METHODS: A 74-year-old female patient was hospitalized for COVID-19. Air leakage was unexpectedly found during imaging reexamination. Considering the unobvious subjective feeling of the patient, a conservative treatment was given at the early stage, and finally, sigmoid colon perforation was surgically confirmed. The family gave up the treatment at last, because the patient could not be taken off the ventilator. Coincidentally, the patient also had abnormal renal anatomical position. This situation led to an abnormal air leakage direction and the atypical manifestations of peritonitis. It was also one of the important reasons for the delayed diagnosis and treatment of the disease.
CONCLUSIONS: Clinicians should be vigilant for spontaneous gastrointestinal perforation in patients with COVID-19, particularly those undergoing treatment with glucocorticoids and tocilizumab. The case is shared to highlight this rare and fatal extrapulmonary manifestation of COVID-19 and further assist clinicians to raise their awareness and timely implement imaging investigation and multidisciplinary intervention so as to facilitate early discovery, diagnosis and treatment and reduce the mortality.

UNASSIGNED: To investigate the short-term changes in chest CT images of low-altitude populations after entering a high-altitude environment.
UNASSIGNED: Chest CT images of 3,587 people from low-altitude areas were obtained within one month of entering a high-altitude environment. Abnormal CT features and clinical symptoms were analyzed.
UNASSIGNED: Besides acute high-altitude pulmonary edema, the incidence of soft tissue space pneumatosis was significantly higher than that in low-altitude areas. Pneumatosis was observed in the mediastinum, cervical muscle space, abdominal cavity, and spinal cord epidural space, especially the mediastinum.
UNASSIGNED: In addition to acute high-altitude pulmonary edema, spontaneous mediastinal emphysema often occurs when individuals in low-altitude areas adapt to the high-altitude environment of cold, low-pressure, and hypoxia. When the gas escapes to the abdominal cavity, it is easy to be misdiagnosed as gastrointestinal perforation. It is also not uncommon for gas accumulation to escape into the epidural space of the spinal cord. The phenomenon of gas diffusion into distant tissue space and the mechanism of gas escape needs to be further studied.

We aimed to determine the clinical characteristics of patient self-inflicted lung injury (P-SILI)-associated pneumothorax/pneumomediastinum, to reveal its risk factors, and to assess its impact on severe COVID-19 cases. In total, 229 patients were included in this case-control study. They were randomly divided into either the case group or the control group as per the inclusion and exclusion criteria. The two groups were further analyzed to reveal the risk factors of spontaneous pneumothorax/pneumomediastinum (SP/P). Finally, risk factors for death were analyzed in the case group and the relationship between death and SP/P was also analyzed among all patients. The mean age of patients was 59.69 ± 17.01 years, most of them were male (74.2%), and 62.0% of them had comorbidities upon admission. A respiratory rate higher than 30 BPM was a risk factor for SP/P (OR 7.186, 95% CI 2.414-21.391, P < 0.001). Patients with delayed intubation due to early application of HFNC or NIV had a higher mortality rate when they developed SP/P (P < 0.05). Additionally, advanced age increased the risk of death (P < 0.05). Finally, SP/P may be a risk factor for death among patients with severe COVID-19 (OR 2.047). P-SILI occurs in severe COVID-19 with acute respiratory failure. It is necessary to identify the risk factors of P-SILI, the indicators of severe P-SILI, and the preventive measures.

Cerebral gas embolism is an unusual but extremely serious condition that occurs when air is introduced into the arterial or venous circulation of the brain. Although rare, it can lead to significant neurological deficits and even the death of the patient.
76-year-old patient with pre-existing diffuse interstitial lung disease, who experienced a massive stroke due to spontaneous pneumomediastinum. Her presentation included confusion, seizures, and motor weakness. Imaging tests revealed air bubbles in the cerebral sulci and hypodense areas in the cerebellum and parietooccipitals. In addition, pneumothorax and air in the upper mediastinum were noted on chest radiographs and chest CT scan. Despite therapeutic measures such as hyperbaric oxygen, the patient unfortunately died due to multiple organ failure.
The diagnosis of cerebral gas embolism generally involves performing a cerebral computed tomography, which is highly sensitive for detecting the presence of air in the cerebral vessels. Management includes monitoring of vital and neurological signs, as well as specific measures such as airway closure, venous catheter aspiration, Trendelenburg positioning, and hyperbaric oxygen.
Cerebral gas embolism is a potentially fatal condition that requires a brain computed tomography for diagnosis and it is vitally important to know the prevention measures to avoid the appearance of this complication and also to know the general measures to adopt when it occurs.
La embolia gaseosa cerebral es una afección inusual pero extremadamente grave que se produce cuando se introduce aire en la circulación arterial o venosa del cerebro. Aunque poco común, puede derivar en déficits neurológicos significativos e incluso la muerte del paciente.
Paciente de 76 años con una enfermedad pulmonar intersticial difusa preexistente, que experimentó un ictus masivo debido a un neumomediastino espontáneo. Su presentación incluyó confusión, convulsiones y debilidad motora. Las pruebas de imagen revelaron burbujas de aire en los surcos cerebrales y áreas hipodensas en el cerebelo y parietooccipitales. Además, se observó neumotórax y aire en el mediastino superior en las radiografías de tórax y la tomografía torácica. A pesar de las medidas terapéuticas como el oxígeno hiperbárico, la paciente lamentablemente falleció debido al fallo multiorgánico.
El diagnóstico de embolia gaseosa cerebral generalmente implica la realización de una tomografía computarizada cerebral, que es altamente sensible para detectar la presencia de aire en los vasos cerebrales. El manejo incluye el control de las constantes vitales y neurológicas, así como medidas específicas como cierre de la entrada de aire, aspiración de catéteres venosos, posicionamiento de Trendelenburg y oxígeno hiperbárico.
La embolia gaseosa cerebral es una afección potencialmente mortal que requiere una tomografía computarizada cerebral para el diagnóstico y de vital importancia conocer las medidas de prevención para evitar la aparición de esta complicación y así mismo conocer las medidas generales a adoptar cuando ésta se presenta.

BACKGROUND: We present a unique case of rhinolalia as the first recognizable sign of spontaneous pneumomediastinum and surgical emphysema following drug use.
METHODS: This case presents a 17-year-old white male experiencing rhinolalia following ecstasy ingestion at a rave. Subsequent chest X-ray revealed extensive surgical emphysema, along with a continuous diaphragm sign indicative of pneumomediastinum. Computed tomography confirmed the diagnosis. The patient was managed conservatively with strict monitoring and 6 hourly electrocardiograms. Follow-up computed tomography on day 3 showed resolution of pneumomediastinum and surgical emphysema, and the patient was safely discharged. Notably, the patient experienced a temporary rhinolalia during the acute phase, which resolved spontaneously as his condition improved.
CONCLUSIONS: This case underscores the importance of considering spontaneous pneumomediastinum and surgical emphysema in the differential diagnosis of young individuals presenting with acute symptoms after drug use.

Implantation of cardiac devices is usually considered to be a safe procedure. Rare complications, such as pneumothorax, may occur after the procedure. The association with pneumopericardium or pneumomediastinum is even more uncommon. We present the case of a patient in his 70s, on haemodialysis, admitted for complete atrioventricular block. He underwent implantation of a dual-chamber pacemaker. He presented with chest pain the day after implantation. Chest CT scan revealed a pneumothorax associated with a pneumopericardium and pneumomediastinum \'pan pneumo\', due to an atrial perforation. We opted for a conservative management strategy. Repeat CT scan of the chest 8 days after the procedure showed a complete resorption of the \'pan pneumo\'. The objective of this case report is to describe this rare complication and provide further insight into its management, particularly in the absence of specific guidelines.

Pneumomediastinum denotes the presence of gas within the mediastinum and generally occurs by leakage of air from an aerated viscus that traverses or abuts the mediastinal plane. The Macklin effect has been described in several veterinary studies and describes gas tracking along the perivascular interstitium following alveolar rupture causing interstitial emphysema, pneumomediastinum and subsequently cervical subcutaneous emphysema. This retrospective case series describes incidental spontaneous pulmonary interstitial emphysema, pneumomediastinum and cervical subcutaneous emphysema secondary to the Macklin effect in dogs with no related clinical signs. Twelve dogs were identified from the author\'s institution, of which 75 % were Sighthounds (Greyhounds, Whippets or Lurchers). Pulmonary interstitial emphysema had a predominantly paravascular distribution, although in some cases a parabronchial distribution was also identified. We conclude that incidental pulmonary interstitial emphysema, pneumomediastinum and secondary cervical subcutaneous emphysema can be incidental, presumed secondary to the Macklin effect and that Sighthound breeds may be overrepresented.

BACKGROUND: An increased incidence of pneumomediastinum has been observed among patients hospitalized with coronavirus disease 2019 (COVID-19) pneumonia. The study aimed to identify risk factors for COVID-19-associated pneumomediastinum and investigate the impact of pneumomediastinum on clinical outcomes.
METHODS: In this multicentre retrospective case-control study, we included consecutive patients with COVID-19 pneumonia and pneumomediastinum hospitalized from March 2020 to July 2020 at ten centres; then, we identified a similarly sized control group of consecutive patients hospitalized with COVID-19 pneumonia and respiratory failure who did not develop pneumomediastinum during the same period. Clinical, laboratory, and radiological characteristics, as well as respiratory support and outcomes, were collected and compared between the two groups. Risk factors of pneumomediastinum were assessed by multivariable logistic analysis.
RESULTS: Overall 139 patients with pneumomediastinum and 153 without pneumomediastinum were analysed. Lung involvement ≥75 %, consolidations, body mass index (BMI) < 22 kg/m2, C-reactive protein (CRP) > 150 mg/L, D-dimer >3000 ng/mL FEUs, and smoking exposure >20 pack-year were all independently correlated with the occurrence of pneumomediastinum. Patients with pneumomediastinum had a longer hospital stay (mean ± SD 31.2 ± 20.2 days vs 19.6 ± 14.2, p < 0.001), higher intubation rate (73/139, 52.5 % vs 27/153, 17.6 %, p < 0.001), and in-hospital mortality (68/139, 48.9 % vs 36/153, 23.5 %, p < 0.001) compared to controls.
CONCLUSIONS: Extensive lung parenchyma involvement, consolidations, low BMI, high inflammatory markers, and tobacco exposure are associated with a greater risk of pneumomediastinum in COVID-19 pneumonia. This complication significantly worsens the outcomes.

Air can become trapped within the subcutaneous layer of the cervicofacial area, a condition known as subcutaneous emphysema (SE), unexpectedly after routine dental procedures. SE can worsen by extending superiorly to the peri-orbital region and inferiorly to the thorax and abdomen along the fascial planes. Upward progression can result in cavernous sinus thrombosis. Conversely, downward progression can cause a variety of complications such as pneumothorax, mediastinitis, and compression of the venous trunks. The presence of these conditions highlights the significance of prompt identification, precise diagnosis to ascertain the need for immediate intervention, and suitable management to prevent additional unfavorable consequences.

BACKGROUND: Pneumomediastinum and pneumorrachis are rare complications following epidural analgesia, that can either be asymptomatic or rarely can produce mild to moderate severity symptoms. Most reported cases regarding the presentation of these two entities with epidural analgesia concern asymptomatic patients, however there are cases reporting post-dural puncture headache and respiratory manifestations.
METHODS: We present a case where a combined lumbar epidural and spinal anesthesia was performed using the loss of resistance to air technique (LOR), on a 78-year-old Greek (Caucasian) male undergoing a total hip replacement. Despite being hemodynamically stable throughout the operation, two hours following epidural analgesia the patient manifested a sudden drop in blood pressure and heart rate that required the administration of adrenaline to counter. Pneumomediastinum, pneumorrachis and paravertebral soft tissue emphysema were demonstrated in a Computed Tomography scan. We believe that injected air from the epidural space and surrounding tissues slowly moved towards the mediastinum, stimulating the para-aortic ganglia causing parasympathetic stimulation and therefore hypotension and bradycardia.
CONCLUSIONS: Anesthesiologists should be aware that epidural analgesia using the LOR to technique injecting air could produce a pneumomediastinum and pneumorrachis, which in turn could produce hemodynamic instability via parasympathetic stimulation.