Inserting a Drainage Strip into the Pre-tracheal Space to Treat Tension Pneumomediastinum: A Case-control Study

Inserting a Drainage Strip into the Pre-tracheal Space to Treat Tension Pneumomediastinum: A Case-control Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Inserting a Drainage Strip into the Pre-tracheal Space to Treat Tension Pneumomediastinum: A Case-control Study Qianli Liu, Xiaohui Li, Zhengzheng Han, Chun Hong This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-275805/v2 This work is licensed under a CC BY 4.0 License Status: Posted Version 2 posted You are reading this latest preprint version Show more versions Abstract Background: Pneumomediastinum is an emergency pediatric disease. A severe tension pneumomediastinum can result in respiratory and circulatory dysfunction. However, few papers describe surgical methods to treat tension pneumomediastinum in a normative manner. Methods: We did a case-control study of 104 pediatric patients with tension pneumomediastinum and comorbid type II respiratory failure. Fifty-two patients were treated with a drainage strip being inserted into the pre-tracheal space while other 52 patients were treated without drainage. Arterial blood pO2 and pCO2 after 30 minutes and 12 hours of mechanical ventilation, chest radiography results after 12 hours of mechanical ventilation, and the length of stay in PICU of the two groups were analyzed by paired t-tests and Chi-square. Results: Chest radiography after 12 hours of mechanical ventilation showed that the pneumomediastinum basically disappeared in the surgery group but did not decrease significantly in the control group. The arterial blood pCO 2 after 12 hours of mechanical ventilation and the length of stay in PICU were significantly lower in the surgery group than in the control group (p<0.001, p<0.001), while the arterial blood pO 2 after 12 hours of mechanical ventilation was significantly higher in the surgery group than in the control group (p<0.001). There were no significant intergroup differences in other variables. No recurrence occurred in either group during 7–14 days after discharge, and all patients recovered. Conclusions: Our method for draining tension pneumomediastinum improved respiratory function and shortened the length of stay in PICU. Trial registration: ChiCTR2000039496. Date of registration : 2021/2/25 (retrospectively registered). Pediatrics drainage pneumomediastinum mediastinum Figures Figure 1 Figure 2 Figure 3 Background Pneumomediastinum is an emergency pediatric disease, with the average age of affected patients being 11 years [ 1 ]. Pneumomediastinum occurs when air enters the mediastinal connective tissue space after alveolar wall rupture. It can simultaneously cause subcutaneous gas accumulation in the suprasternal fossae, supraclavicular fossae, lateral chest wall, etc. Common etiologies include severe pneumonia such as COVID-19 pneumonia, asthma, excessive pressure from a ventilator, abdominal trauma or surgery, etc [ 2 , 3 ]. Mild and moderate cases without obvious respiratory dysfunction or circulatory dysfunction can be cured by inhaling oxygen, analgesic, antibiotics and waiting for the body to absorb. However, in severe cases, accumulation of large amounts of gas in the mediastinum can cause relatively large tension, leading to compression symptoms similar to tension pneumothorax. This compresses the lung tissue, resulting in dyspnea, and also compresses the mediastinal vena cava, thus impeding blood flow back to the heart and causing circulatory dysfunction [ 4 – 6 ]. This condition requires timely gas expulsion and decompression. Although there have been reports of thoracoscopic treatment, however, this is usually achieved by using a thick needle for puncture or using a scalpel to make small incisions in the skin corresponding to the site of pneumomediastinum to release gas, or making a single incision and then inserting a subcutaneous drainage strip for drainage [ 4 , 5 , 7 ]. Few papers describe these methods in a normative manner. This paper combines the local anatomical characteristics to describe a method for draining tension pneumomediastinum. We present the following article in accordance with the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) reporting checklist. Methods Criteria, defines and data sources We retrospectively analysed the treatment of patients whose inclusion criteria were: 1) treated in the PICU (Pediatric Intensive Care Unit) of our hospital between January 2011 and July 2021; 2) tension pneumomediastinum; and 3) type II respiratory failure. Exclusion criteria were: 1) asthmatic attack; 2) the bullae of lung ruptured; 3) the cystadenoma of lung was obviously distended; 4) combined heart disease. The tension pneumomediastinum in these four conditions cannot be eliminated by simple drainage or by waiting for the body to absorb it, so they are confounding factors and should be excluded. The descriptions of Kouritas and Clancy were used as the definition of tension pneumomediastinum: accumulation of large amounts of gas in the mediastinum causes relatively large tension, leading to compression symptoms similar to tension pneumothorax. It compresses the lung tissue, resulting in dyspnea, and also compresses the mediastinal vena cava, thus impeding blood flow back to the heart and causing circulatory dysfunction [ 4 , 8 ]. Arterial blood pO2 (pressure of oxygen) and pCO2 (pressure of carbon dioxide) were obtained by bedside blood gas analysis and, because they directly reflect changes in respiratory function, served as predictors of changes in pneumomediastinum. The changes of pneumomediastinum were directly observed by bedside chest radiograph. Type II respiratory failure: arterial blood pO2 6.7Kpa (50mmHg). Grouping and Statistics Patients were divided into surgery group and control group based on whether or not drainage was performed. Since body develops with age, the two patient groups were paired 1:1 by similar age. We compared the baseline data, arterial blood pO 2 and pCO 2 after 30 minutes and 12 hours of mechanical ventilation, the length of stay in PICU, and chest radiography results after 12 hours of mechanical ventilation between groups. After discharge, all patients were followed up for 7–14 days. SPSS 22 software (IBM SPSS Statistics, RRID:SCR_019096) was used to perform paired t-tests of measurement data, and count data were analyzed by Chi-square. P < 0.05 indicated statistical significance. (Fig. 1 ) We controlled for selective bias by strictly enforcing inclusion and exclusion criteria, and controlled for information bias by having all authors collect all data independently and check against each other. Drainage procedure in surgery group ① The left and right angles of the rhombic region encircled by the anterior borders of the left and right sternocleidomastoid muscles and the sternohyoid muscles were used as the positions of the left and right incisions, and were indicated on the skin using a marker (Fig. 3 A). ② We used sterile rubber gloves to make a drainage strip with a width of 1.5cm and a length that were 3cm longer than the distance between the two incisions. ③ After routine skin disinfection and laying of surgical drapes, we used a scalpel to make 5-mm longitudinal incisions at the left and right skin marks. Curved forceps were inserted into the right incision for blunt dissection of subcutaneous tissues. The superficial fascia of the neck was punctured. At this point, there was a feeling of emptiness after penetration. Subsequently, the forceps were inserted into the pre-tracheal space and a blunt dissection of the pre-tracheal space from right to left was made until the site of the left (contralateral) incision was reached. The superficial fascia of the neck was punctured from the medial to the lateral side, and the forceps came out through the left incision. During blunt dissection of the pre-tracheal space, we palpated the trachea with our fingers to determine its position and to avoid damaging it (Fig. 3 B). ④ We used the end of the curved forceps outside the left incision to clamp one end of the pre-made rubber drainage strip and the forceps were slowly withdrawn from the dissection tunnel, thereby introducing the drainage strip slowly into the tunnel. We left 1.5cm of the drainage strip outside each of the two incisions to ensure that the ends of the drainage strip would not easily slip into the subcutaneous tissue (Fig. 3 C, D; Fig. 2 B). ⑤ We disinfected and bandaged the incision site. ⑥ Chest radiography was carried out 12 hours later (Fig. 2 C). If no significant pneumomediastinum was found, the drainage strip was removed 1–3 days later without the need for suturing the incision site. Results The surgery group included 52 patients treated in our hospital between September 2015 and July 2021 in whom a drainage tube was inserted into the pre-tracheal space to drain the pneumomediastinum after the arterial blood gas analysis results were obtained. The control group included 52 patients treated in our hospital between January 2011 and December 2016 in whom no drainage tube was placed after the arterial blood gas analysis results were obtained. All patients received endotracheal intubation and mechanical ventilation. After 30 minutes of mechanical ventilation, blood oxygen saturation, at above 75%, was not stabilised, and arterial blood gas analysis showed a low partial pO 2 and a high partial pCO 2 . Arterial blood gas analysis and chest radiography were repeated for all paediatric patients after 12 hours of mechanical ventilation. Patients were weaned from mechanical ventilation once chest radiography showed that the pneumonia was controlled. The ventilator parameters were gradually decreased to an oxygen concentration ≤ 30%, oxygen flow rate ≤ 1.5 L/min, and respiratory rate ≤ 35 bpm. There were no significant intergroup differences in sex (χ 2 = 0.347, p = 0.556), age (95% CI -0.687 to 0.033, p = 0.074), weight (95% CI -0.675 to 0.125, p = 0.173), arterial blood pO 2 and pCO 2 after 30 minutes of mechanical ventilation (95% CI -2.524 to 0.793, p = 0.300; 95% CI − .0136 to 2.014, p = 0.053). (Table 1 ) Table 1 Baseline data, arterial blood pO2 and pCO2 after 30 minutes of mechanical ventilation Item n Mean Std. Deviation 95% CI P value Sex S 52, F29, M23 -- -- -- -- Sex C 52, F26, M26 -- -- -- -- Crosstabs Sex S - C 104 -- -- -- 0.556 Age S (month) 52 26.1731 26.478 -- -- Age C 52 26.500 26.643 -- -- Pair Age S - C 52 -0.3269 1.294 -0.687 to 0.033 0.074 Weight S (kg) 52 12.187 6.023 -- -- Weight C 52 12.462 6.392 -- -- Pair Weight S - C 52 -0.2750 1.435 -0.675 to 0.125 0.173 pO 2 1 S (mmHg) 52 53.000 4.736 -- -- pO 2 1 C 52 53.865 3.825 -- -- Pair pO 2 1 S - C 52 -0.865 5.957 -2.524 to 0.793 0.300 pCO 2 1 S (mmHg) 52 56.096 3.057 -- -- pCO 2 1 C 52 55.096 2.885 -- -- Pair pCO 2 1 S - C 52 1.000 3.641 -0.014 to 2.013 0.053 S: Surgery group. C: Control group. M: male. F: female. pO 2 1: Arterial blood pO 2 after 30 minutes of mechanical ventilation. pCO 2 1: Arterial blood pCO2 after 30 minutes of mechanical ventilation. Chest radiography after 12 hours of mechanical ventilation showed that the pneumomediastinum basically disappeared in the surgery group but did not decrease significantly in the control group. The operative time ranged from 20 to 35 minutes (29.865 ± 3.162). No tracheal or vascular was damaged. The arterial blood pCO 2 after 12 hours of mechanical ventilation and the length of stay in PICU were significantly lower in the surgery group than in the control group (95% CI -4.649 to -2.813, p < 0.001; 95% CI -5.021 to -3.325, p < 0.001), while the arterial blood pO 2 after 12 hours of mechanical ventilation was significantly higher in the surgery group than in the control group (95% CI 4.031 to 5.969, p < 0.001). There were no significant intergroup differences in follow-up (95% CI -1.315 to 0.007, p = 0.053). No recurrence occurred in either group during 7–14 days of follow-up, and all patients recovered. (Table 2 ) Table 2 Post-operative data Item n Mean Std. Deviation 95% CI P value Duration (minute) 52 29.865 3.162 -- -- pO 2 2 S (mmHg) 52 76.154 2.363 -- -- pO 2 2 C 52 71.154 3.032 -- -- Pair pO 2 2 S - C 52 5.000 3.481 4.031 to 5.969 0.001 pCO 2 2 S (mmHg) 52 40.385 2.378 -- -- pCO 2 2 C 52 44.115 2.349 -- -- Pair pCO 2 2 S - C 52 -3.731 3.297 -4.649 to -2.813 0.001 Length S (day) 52 9.789 1.903 -- -- Length C 52 13.962 2.205 -- -- Pair Length S - C 52 -4.173 3.047 -5.021 to -3.325 0.001 Follow-up S (day) 52 10.173 1.654 -- -- Follow-up C 52 10.827 1.735 -- -- Pair Follow-up S - C 52 -0.653 2.375 -1.315 to 0.007 0.053 S: Surgery group. C: Control group. Duration: Duration of surgery. Length: Length, the length of stay in PICU. pO 2 2: Arterial blood pO 2 after 12 hours of mechanical ventilation. pCO 2 2: Arterial blood pCO 2 after 12 hours of mechanical ventilation. Sample size calculation The sample size was determined by the mean and standard deviation of the difference in the primary endpoint, the length of stay in PICU. The paired design data is measurement data, and the difference is normally distributed (W = 0.981, P = 0.588, δ = -4.173, σ = 3.047, Table 3), using paired t test, and sample size was calculated following the formula: n=(t α +t β ) 2 σ 2 /δ 2 [ 9 ]. At least 8 pairs were needed for testing. Discussion The mediastinal space is a narrow space between organs in the mediastinum that is filled with loose connective tissue to accommodate organ activities and changes in volume. The connective tissues of the mediastinal space extend upwards and are continuous with the connective tissues of the neck. The pre-tracheal space is located between the upper mediastinum, trachea, bifurcation of trachea, and aortic arch. It communicates upward with the pre-tracheal space in the neck. Gas can diffuse upwards to the neck when pneumomediastinum occurs (Fig. 2 B). A layer of superficial fascia exists between the mediastinal space and the skin. This layer of superficial fascia is dense and gas cannot easily diffuse through it. The pre-tracheal space lies behind the superficial fascia of the neck, in a rhombic region formed between the anterior borders of the bilateral sternocleidomastoid muscles and the anterior borders of the bilateral sternohyoid muscles (Fig. 2 A). This area contains the anterior jugular vein, the jugular venous arch, and the inferior thyroid vein. When performing this procedure, blunt dissection must be used to reduce the risk of injury to these veins [ 10 ]. It is much more difficult to control the anatomical layer accessed by the incision when using a needle or small incision to expel gas. Thus, the superficial fascia may not be punctured due to fear of causing vascular and nerve injury, resulting in the drainage of only small volumes of gas outside the superficial fascia. Even if the superficial fascia has been punctured and gas can be effectively expelled for a short while, the superficial fascia contraction will cause the puncture site to rapidly close, and subsequently, gas cannot be effectively drained. In the single incision drainage strip method, although the drainage strip can enter the sub-superficial fascial space, the position of drainage strip cannot be easily fixed. Thus, it tends to slip out into the anatomical layers beyond the superficial fascia when the forceps are withdrawn, leading to ineffective drainage. We used curved forceps for blunt dissection to create a drainage tunnel, which had a clear anatomical level and precise location, thus preventing damage to the trachea and veins. The drainage strip passed through a longer route accurately inside the pre-tracheal space to connect the pneumomediastinal space with the skin incision for sufficient drainage. The significant differences in arterial partial pressure of oxygen and partial pressure of carbon dioxide in the 12th hour of mechanical ventilation between the two groups suggest that the surgery could relieve the pressure of tension pneumomediastinum on the airway, heart, and lungs, improve blood circulation, promote the diffusion and mutual exchange of carbon dioxide and oxygen, leading to the significant difference in total length of mechanical ventilation between the two groups. The two ends of the drainage strip were located outside the skin and were fixed, which facilitates observation. The treatment duration was shortened due to high efficiency of the operation. Nevertheless, this procedure raised the risk of infection and skin scarring. This study aims to provide a standard and effective drainage method for tension pneumomediastinum occurring from various causes, as well as to provide a reference for the treatment of tension pneumomediastinum caused by COVID-19. Clinicians should carefully consider the following points before selecting this method: familiarity with the local anatomical structure of the pre-tracheal region, as failure to accurately enter the pre-tracheal space will lead to ineffective operation; the method has the risks of damaging the trachea and increasing the infection routes. Respiratory function improvements could not be completely attributed to drainage of the tension pneumomediastinum, as the treatment of primary diseases such as pneumonia and respiratory distress syndrome also resulted in gas absorption. The contribution of drainage could not be accurately determined since the sample size was too small and additional control groups were lacking, affecting the accuracy of the conclusion. Conclusions Our method for draining tension pneumomediastinum improved respiratory function and shortened the length of stay in PICU. However, further studies are required to confirm these findings. Abbreviations STROBE: Strengthening the Reporting of Observational Studies in Epidemiology; PICU: Pediatric Intensive Care Unit; pO2: pressure of oxygen; pCO2: pressure of carbon dioxide Declarations Ethics approval and consent to participate The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The trial was conducted in accordance with the Declaration of Helsinki (as revised in 2013). The study was approved by Guangdong Women and Children Hospital Medical Ethics Committee (No. 202001190) and informed consent was taken from all individual participants. Consent for publication Informed consent was obtained from the legal parent or guardian of each child. All the parents and guardians consented to the publication of their data. Availability of data and materials Technical appendix, statistical code, and dataset available from the FigShare repository, https://doi.org/10.6084/m9.figshare.13487295. Competing interests The authors declare that they have no conflicts of interest. Funding Not applicable. Authors' contributions QLL made the conception and design of the study, performed the operations, drafted the manuscript, and made data analysis and interpretation. CH and ZZH gave administrative support. All authors collected all data independently and checked the data against each other. All authors contributed to the critical revision of the manuscript, and approved its final form. Acknowledgements Not applicable. References Andrew E, Newcomb C, Peter Clarke. Spontaneous pneumomediastinum: a benign curiosity or a significant problem? Chest. 2005 Nov;128(5):3298–302. https://doi.org/10.1378/chest.128.5.3298 . Desai A, Caldwell C, Hirschl D, et al. TENSION PNEUMOMEDIASTINUM IN A PATIENT WITH COVID-19 PNEUMONIA. Chest. 2020;158(4):A1028. https://doi.org/10.1016/j.chest.2020.08.955 . Campisi A, Poletti V, Ciarrocchi AP, et al. Tension pneumomediastinum in patients with COVID-19. Thorax. 2020;75(12):1130–1. https://doi.org/10.1136/thoraxjnl-2020-215012 . Kouritas VK, Papagiannopoulos K, Lazaridis G, et al. Pneumomediastinum J Thorac Dis. 2015;7(S1):44–9. https://doi.org/10.3978/j.issn.2072-1439.2015.01.11 . MCNICHOLL B. Pneumomediastinum and subcutaneous emphysema in status asthmaticus, requiring surgical decompression. Archives of disease in childhood 1960;35(182), 389–392. https://doi.org/10.1136/adc.35.182.389 . Abu-Omar Y, Catarino PA. Progressive subcutaneous emphysema and respiratory arrest. J R Soc Med. 2002 Feb;95(2):90–1. https://doi.org/10.1258/jrsm.95.2.90 . O'Reilly P, Chen HK, Wiseman R. Management of extensive subcutaneous emphysema with a subcutaneous drain. Respirol Case Rep. 2013 Dec;1(2):28–30. https://doi.org/10.1002/rcr2.9 . Clancy DJ, Lane AS, Flynn PW, et al. Tension pneumomediastinum: A literal form of chest tightness. Journal of the Intensive Care Society. 2017;18(1):52–6. https://doi.org/10.1177/1751143716662665 . Hajian-Tilaki K. Sample size estimation in epidemiologic studies. Caspian J Intern Med. 2011;2(4):289–98. Wells FC, Coonar AS. Anatomy of the Mediastinum. Thoracic Surgical Techniques. Springer, Cham 2018:pp. 187–90. https://doi.org/10.1007/978-3-319-66270-1_44 . Supplementary Files Samplesizecalculation.docx Cite Share Download PDF Status: Posted Version 2 posted You are reading this latest preprint version Show more versions Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-275805","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":52408978,"identity":"9aec3ea0-205e-400a-a0f5-8cda8fa7b358","order_by":0,"name":"Qianli Liu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAqElEQVRIiWNgGAWjYBACfvbm4x8S/9iQoEWy51gaw8eGNBK0GMzwMWOc2XCYFC0SDGaPeXecl+07wPzw0Q1itJhLN6Qb8565bTzzAJuxcQ4xWiznHDggzcN2O3HDAR42aaK0GNxIbABqOUeSlmQ2yZltB0jQAgxkZoMPZ5KNZx4m1i/87P0fHyRU2Mn2HW9++JgoLTDASFLUQLUcIFXLKBgFo2AUjBgAAOyqOH2XsMnAAAAAAElFTkSuQmCC","orcid":"https://orcid.org/0000-0001-8629-4035","institution":"Guangdong Women and Children Hospital","correspondingAuthor":true,"prefix":"","firstName":"Qianli","middleName":"","lastName":"Liu","suffix":""},{"id":52408979,"identity":"ae93fd3e-abed-4826-8115-2f37ba421d77","order_by":1,"name":"Xiaohui Li","email":"","orcid":"","institution":"Guangdong Women and Children Hospital","correspondingAuthor":false,"prefix":"","firstName":"Xiaohui","middleName":"","lastName":"Li","suffix":""},{"id":52408980,"identity":"d35533f7-fc78-4cbc-a9de-932538d9b589","order_by":2,"name":"Zhengzheng Han","email":"","orcid":"","institution":"Guangdong Women and Children Hospital","correspondingAuthor":false,"prefix":"","firstName":"Zhengzheng","middleName":"","lastName":"Han","suffix":""},{"id":52408981,"identity":"19607fb6-95c9-4e9a-91ed-0214002f3fc9","order_by":3,"name":"Chun Hong","email":"","orcid":"","institution":"Guangdong Women and Children Hospital","correspondingAuthor":false,"prefix":"","firstName":"Chun","middleName":"","lastName":"Hong","suffix":""}],"badges":[],"createdAt":"2021-02-25 13:14:10","currentVersionCode":2,"declarations":"","doi":"10.21203/rs.3.rs-275805/v2","doiUrl":"https://doi.org/10.21203/rs.3.rs-275805/v2","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":13715650,"identity":"e92a1ba9-c22e-4022-970b-fa95c3a8eb20","added_by":"auto","created_at":"2021-09-17 14:49:22","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":100675,"visible":true,"origin":"","legend":"Flowchart of this study","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-275805/v2/29c6cef3e94fb124b2802b3b.png"},{"id":13715147,"identity":"13edc621-1c29-49b3-936f-08fc2c9e1880","added_by":"auto","created_at":"2021-09-17 14:46:23","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":953424,"visible":true,"origin":"","legend":"Radiographic data\nA. The pre-tracheal space: it lies in a rhombic region formed between the anterior borders of the bilateral sternocleidomastoid muscles and the anterior borders of the bilateral sternohyoid muscles (the part enclosed by red line); B. The Pre-tracheal Space and the location of drainage: a. The Pre-tracheal Space, b. Tracheal, c. A drainage strip and the position of drainage, d. Pneumomediastinum; C. Computer Tomography after 12 hours of drainage.\n","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-275805/v2/845bb31d7306811fd561e011.png"},{"id":13715145,"identity":"051c0d58-cc15-4930-bae3-360fc3056352","added_by":"auto","created_at":"2021-09-17 14:46:22","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":1688534,"visible":true,"origin":"","legend":"Operational process\nA. The positions of the left and right incisions: a. Right incision, b. Left incision; B. The curved forceps were passed through the pre-tracheal space and the two incisions; C. We used the end of the curved forceps outside the left incision to clamp one end of the pre-made rubber drainage strip; D. The forceps were slowly withdrawn from the dissection tunnel, thereby introducing the drainage strip slowly into the tunnel.\n","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-275805/v2/a264939ea324a71b23556cee.png"},{"id":13747323,"identity":"d5781ba5-db26-4541-a336-5e1bf89afe4d","added_by":"auto","created_at":"2021-09-18 15:49:43","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2673451,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-275805/v2/3902f1b0-ef75-40b1-8dbd-0752a6851cf5.pdf"},{"id":13715148,"identity":"a99613bc-3120-4a3a-936b-f34fe3478ef9","added_by":"auto","created_at":"2021-09-17 14:46:23","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":23077,"visible":true,"origin":"","legend":"","description":"","filename":"Samplesizecalculation.docx","url":"https://assets-eu.researchsquare.com/files/rs-275805/v2/f0fa4b6f750fbb7947de4dde.docx"}],"financialInterests":"","formattedTitle":"\u003cp\u003eInserting a Drainage Strip into the Pre-tracheal Space to Treat Tension Pneumomediastinum: A Case-control Study\u003c/p\u003e","fulltext":[{"header":"Background","content":"\u003cp\u003ePneumomediastinum is an emergency pediatric disease, with the average age of affected patients being 11 years [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Pneumomediastinum occurs when air enters the mediastinal connective tissue space after alveolar wall rupture. It can simultaneously cause subcutaneous gas accumulation in the suprasternal fossae, supraclavicular fossae, lateral chest wall, etc. Common etiologies include severe pneumonia such as COVID-19 pneumonia, asthma, excessive pressure from a ventilator, abdominal trauma or surgery, etc [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Mild and moderate cases without obvious respiratory dysfunction or circulatory dysfunction can be cured by inhaling oxygen, analgesic, antibiotics and waiting for the body to absorb. However, in severe cases, accumulation of large amounts of gas in the mediastinum can cause relatively large tension, leading to compression symptoms similar to tension pneumothorax. This compresses the lung tissue, resulting in dyspnea, and also compresses the mediastinal vena cava, thus impeding blood flow back to the heart and causing circulatory dysfunction [\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. This condition requires timely gas expulsion and decompression. Although there have been reports of thoracoscopic treatment, however, this is usually achieved by using a thick needle for puncture or using a scalpel to make small incisions in the skin corresponding to the site of pneumomediastinum to release gas, or making a single incision and then inserting a subcutaneous drainage strip for drainage [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Few papers describe these methods in a normative manner. This paper combines the local anatomical characteristics to describe a method for draining tension pneumomediastinum. We present the following article in accordance with the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) reporting checklist.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv class=\"Section2\" id=\"Sec3\"\u003e\n \u003ch2\u003eCriteria, defines and data sources\u003c/h2\u003e\n \u003cp\u003eWe retrospectively analysed the treatment of patients whose inclusion criteria were: 1) treated in the PICU (Pediatric Intensive Care Unit) of our hospital between January 2011 and July 2021; 2) tension pneumomediastinum; and 3) type II respiratory failure.\u003c/p\u003e\n \u003cp\u003eExclusion criteria were: 1) asthmatic attack; 2) the bullae of lung ruptured; 3) the cystadenoma of lung was obviously distended; 4) combined heart disease. The tension pneumomediastinum in these four conditions cannot be eliminated by simple drainage or by waiting for the body to absorb it, so they are confounding factors and should be excluded.\u003c/p\u003e\n \u003cp\u003eThe descriptions of Kouritas and Clancy were used as the definition of tension pneumomediastinum: accumulation of large amounts of gas in the mediastinum causes relatively large tension, leading to compression symptoms similar to tension pneumothorax. It compresses the lung tissue, resulting in dyspnea, and also compresses the mediastinal vena cava, thus impeding blood flow back to the heart and causing circulatory dysfunction [\u003cspan class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e\n \u003cp\u003eArterial blood pO2 (pressure of oxygen) and pCO2 (pressure of carbon dioxide) were obtained by bedside blood gas analysis and, because they directly reflect changes in respiratory function, served as predictors of changes in pneumomediastinum. The changes of pneumomediastinum were directly observed by bedside chest radiograph.\u003c/p\u003e\n \u003cp\u003eType II respiratory failure: arterial blood pO2\u0026thinsp;\u0026lt;\u0026thinsp;8.0Kpa (60mmHg) and pCO2\u0026thinsp;\u0026gt;\u0026thinsp;6.7Kpa (50mmHg).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\" id=\"Sec4\"\u003e\n \u003ch2\u003eGrouping and Statistics\u003c/h2\u003e\n \u003cp\u003ePatients were divided into surgery group and control group based on whether or not drainage was performed. Since body develops with age, the two patient groups were paired 1:1 by similar age. We compared the baseline data, arterial blood pO\u003csub\u003e2\u003c/sub\u003e and pCO\u003csub\u003e2\u003c/sub\u003e after 30 minutes and 12 hours of mechanical ventilation, the length of stay in PICU, and chest radiography results after 12 hours of mechanical ventilation between groups. After discharge, all patients were followed up for 7\u0026ndash;14 days. SPSS 22 software (IBM SPSS Statistics, RRID:SCR_019096) was used to perform paired t-tests of measurement data, and count data were analyzed by Chi-square. P\u0026thinsp;\u0026lt;\u0026thinsp;0.05 indicated statistical significance. (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e)\u003c/p\u003e\n \u003cp\u003eWe controlled for selective bias by strictly enforcing inclusion and exclusion criteria, and controlled for information bias by having all authors collect all data independently and check against each other.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\" id=\"Sec5\"\u003e\n \u003ch2\u003eDrainage procedure in surgery group\u003c/h2\u003e\n \u003cp\u003e① The left and right angles of the rhombic region encircled by the anterior borders of the left and right sternocleidomastoid muscles and the sternohyoid muscles were used as the positions of the left and right incisions, and were indicated on the skin using a marker (Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eA). ② We used sterile rubber gloves to make a drainage strip with a width of 1.5cm and a length that were 3cm longer than the distance between the two incisions. ③ After routine skin disinfection and laying of surgical drapes, we used a scalpel to make 5-mm longitudinal incisions at the left and right skin marks. Curved forceps were inserted into the right incision for blunt dissection of subcutaneous tissues. The superficial fascia of the neck was punctured. At this point, there was a feeling of emptiness after penetration. Subsequently, the forceps were inserted into the pre-tracheal space and a blunt dissection of the pre-tracheal space from right to left was made until the site of the left (contralateral) incision was reached. The superficial fascia of the neck was punctured from the medial to the lateral side, and the forceps came out through the left incision. During blunt dissection of the pre-tracheal space, we palpated the trachea with our fingers to determine its position and to avoid damaging it (Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eB). ④ We used the end of the curved forceps outside the left incision to clamp one end of the pre-made rubber drainage strip and the forceps were slowly withdrawn from the dissection tunnel, thereby introducing the drainage strip slowly into the tunnel. We left 1.5cm of the drainage strip outside each of the two incisions to ensure that the ends of the drainage strip would not easily slip into the subcutaneous tissue (Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eC, D; Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eB). ⑤ We disinfected and bandaged the incision site. ⑥ Chest radiography was carried out 12 hours later (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eC). If no significant pneumomediastinum was found, the drainage strip was removed 1\u0026ndash;3 days later without the need for suturing the incision site.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eThe surgery group included 52 patients treated in our hospital between September 2015 and July 2021 in whom a drainage tube was inserted into the pre-tracheal space to drain the pneumomediastinum after the arterial blood gas analysis results were obtained. The control group included 52 patients treated in our hospital between January 2011 and December 2016 in whom no drainage tube was placed after the arterial blood gas analysis results were obtained. All patients received endotracheal intubation and mechanical ventilation. After 30 minutes of mechanical ventilation, blood oxygen saturation, at above 75%, was not stabilised, and arterial blood gas analysis showed a low partial pO\u003csub\u003e2\u003c/sub\u003e and a high partial pCO\u003csub\u003e2\u003c/sub\u003e. Arterial blood gas analysis and chest radiography were repeated for all paediatric patients after 12 hours of mechanical ventilation. Patients were weaned from mechanical ventilation once chest radiography showed that the pneumonia was controlled. The ventilator parameters were gradually decreased to an oxygen concentration\u0026thinsp;\u0026le;\u0026thinsp;30%, oxygen flow rate\u0026thinsp;\u0026le;\u0026thinsp;1.5 L/min, and respiratory rate\u0026thinsp;\u0026le;\u0026thinsp;35 bpm. There were no significant intergroup differences in sex (\u0026chi;\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.347, p\u0026thinsp;=\u0026thinsp;0.556), age (95% CI -0.687 to 0.033, p\u0026thinsp;=\u0026thinsp;0.074), weight (95% CI -0.675 to 0.125, p\u0026thinsp;=\u0026thinsp;0.173), arterial blood pO\u003csub\u003e2\u003c/sub\u003e and pCO\u003csub\u003e2\u003c/sub\u003e after 30 minutes of mechanical ventilation (95% CI -2.524 to 0.793, p\u0026thinsp;=\u0026thinsp;0.300; 95% CI \u0026minus;\u0026thinsp;.0136 to 2.014, p\u0026thinsp;=\u0026thinsp;0.053). (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e)\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable border=\"1\" id=\"Tab1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eBaseline data, arterial blood pO2 and pCO2 after 30 minutes of mechanical ventilation\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eItem\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003en\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eStd. Deviation\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e95% CI\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSex S\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e52, F29, M23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSex C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e52, F26, M26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCrosstabs Sex S - C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e104\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.556\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAge S (month)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e26.1731\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e26.478\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAge C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e26.500\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e26.643\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePair Age S - C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.3269\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.294\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.687 to 0.033\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.074\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eWeight S (kg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12.187\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.023\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eWeight C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12.462\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.392\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePair Weight S - C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2750\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.435\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.675 to 0.125\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.173\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003epO\u003csub\u003e2\u003c/sub\u003e 1 S (mmHg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e53.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.736\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003epO\u003csub\u003e2\u003c/sub\u003e 1 C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e53.865\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.825\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePair pO\u003csub\u003e2\u003c/sub\u003e 1 S - C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.865\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.957\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-2.524 to 0.793\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.300\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003epCO\u003csub\u003e2\u003c/sub\u003e 1 S (mmHg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e56.096\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.057\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003epCO\u003csub\u003e2\u003c/sub\u003e 1 C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e55.096\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.885\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePair pCO\u003csub\u003e2\u003c/sub\u003e 1 S - C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.641\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.014 to 2.013\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.053\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003eS: Surgery group. C: Control group. M: male. F: female. pO\u003csub\u003e2\u003c/sub\u003e 1: Arterial blood pO\u003csub\u003e2\u003c/sub\u003e after 30 minutes of mechanical ventilation. pCO\u003csub\u003e2\u003c/sub\u003e 1: Arterial blood pCO2 after 30 minutes of mechanical ventilation.\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eChest radiography after 12 hours of mechanical ventilation showed that the pneumomediastinum basically disappeared in the surgery group but did not decrease significantly in the control group. The operative time ranged from 20 to 35 minutes (29.865\u0026thinsp;\u0026plusmn;\u0026thinsp;3.162). No tracheal or vascular was damaged. The arterial blood pCO\u003csub\u003e2\u003c/sub\u003e after 12 hours of mechanical ventilation and the length of stay in PICU were significantly lower in the surgery group than in the control group (95% CI -4.649 to -2.813, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001; 95% CI -5.021 to -3.325, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), while the arterial blood pO\u003csub\u003e2\u003c/sub\u003e after 12 hours of mechanical ventilation was significantly higher in the surgery group than in the control group (95% CI 4.031 to 5.969, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). There were no significant intergroup differences in follow-up (95% CI -1.315 to 0.007, p\u0026thinsp;=\u0026thinsp;0.053). No recurrence occurred in either group during 7\u0026ndash;14 days of follow-up, and all patients recovered. (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable border=\"1\" id=\"Tab2\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003ePost-operative data\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eItem\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003en\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eStd. Deviation\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e95% CI\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDuration (minute)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e29.865\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.162\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003epO\u003csub\u003e2\u003c/sub\u003e 2 S (mmHg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e76.154\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.363\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003epO\u003csub\u003e2\u003c/sub\u003e 2 C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e71.154\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.032\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePair pO\u003csub\u003e2\u003c/sub\u003e 2 S - C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.481\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.031 to 5.969\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003epCO\u003csub\u003e2\u003c/sub\u003e 2 S (mmHg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e40.385\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.378\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003epCO\u003csub\u003e2\u003c/sub\u003e 2 C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e44.115\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.349\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePair pCO\u003csub\u003e2\u003c/sub\u003e 2 S - C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-3.731\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.297\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-4.649 to -2.813\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLength S (day)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e9.789\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.903\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLength C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e13.962\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.205\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePair Length S - C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-4.173\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.047\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-5.021 to -3.325\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFollow-up S (day)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e10.173\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.654\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFollow-up C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e10.827\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.735\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e--\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePair Follow-up S - C\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-0.653\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.375\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-1.315 to 0.007\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.053\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003eS: Surgery group. C: Control group. Duration: Duration of surgery. Length: Length, the length of stay in PICU. pO\u003csub\u003e2\u003c/sub\u003e 2: Arterial blood pO\u003csub\u003e2\u003c/sub\u003e after 12 hours of mechanical ventilation. pCO\u003csub\u003e2\u003c/sub\u003e 2: Arterial blood pCO\u003csub\u003e2\u003c/sub\u003e after 12 hours of mechanical ventilation.\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\" id=\"Sec7\"\u003e\n \u003ch2\u003eSample size calculation\u003c/h2\u003e\n \u003cp\u003eThe sample size was determined by the mean and standard deviation of the difference in the primary endpoint, the length of stay in PICU. The paired design data is measurement data, and the difference is normally distributed (W\u0026thinsp;=\u0026thinsp;0.981, P\u0026thinsp;=\u0026thinsp;0.588, \u0026delta; = -4.173, \u0026sigma;\u0026thinsp;=\u0026thinsp;3.047, Table\u0026nbsp;3), using paired t test, and sample size was calculated following the formula: n=(t\u003csub\u003e\u0026alpha;\u003c/sub\u003e+t\u003csub\u003e\u0026beta;\u003c/sub\u003e)\u003csup\u003e2\u003c/sup\u003e\u0026sigma;\u003csup\u003e2\u003c/sup\u003e/\u0026delta;\u003csup\u003e2\u003c/sup\u003e [\u003cspan class=\"CitationRef\"\u003e9\u003c/span\u003e]. At least 8 pairs were needed for testing.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe mediastinal space is a narrow space between organs in the mediastinum that is filled with loose connective tissue to accommodate organ activities and changes in volume. The connective tissues of the mediastinal space extend upwards and are continuous with the connective tissues of the neck. The pre-tracheal space is located between the upper mediastinum, trachea, bifurcation of trachea, and aortic arch. It communicates upward with the pre-tracheal space in the neck. Gas can diffuse upwards to the neck when pneumomediastinum occurs (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB). A layer of superficial fascia exists between the mediastinal space and the skin. This layer of superficial fascia is dense and gas cannot easily diffuse through it. The pre-tracheal space lies behind the superficial fascia of the neck, in a rhombic region formed between the anterior borders of the bilateral sternocleidomastoid muscles and the anterior borders of the bilateral sternohyoid muscles (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA). This area contains the anterior jugular vein, the jugular venous arch, and the inferior thyroid vein. When performing this procedure, blunt dissection must be used to reduce the risk of injury to these veins [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIt is much more difficult to control the anatomical layer accessed by the incision when using a needle or small incision to expel gas. Thus, the superficial fascia may not be punctured due to fear of causing vascular and nerve injury, resulting in the drainage of only small volumes of gas outside the superficial fascia. Even if the superficial fascia has been punctured and gas can be effectively expelled for a short while, the superficial fascia contraction will cause the puncture site to rapidly close, and subsequently, gas cannot be effectively drained.\u003c/p\u003e \u003cp\u003eIn the single incision drainage strip method, although the drainage strip can enter the sub-superficial fascial space, the position of drainage strip cannot be easily fixed. Thus, it tends to slip out into the anatomical layers beyond the superficial fascia when the forceps are withdrawn, leading to ineffective drainage.\u003c/p\u003e \u003cp\u003eWe used curved forceps for blunt dissection to create a drainage tunnel, which had a clear anatomical level and precise location, thus preventing damage to the trachea and veins. The drainage strip passed through a longer route accurately inside the pre-tracheal space to connect the pneumomediastinal space with the skin incision for sufficient drainage. The significant differences in arterial partial pressure of oxygen and partial pressure of carbon dioxide in the 12th hour of mechanical ventilation between the two groups suggest that the surgery could relieve the pressure of tension pneumomediastinum on the airway, heart, and lungs, improve blood circulation, promote the diffusion and mutual exchange of carbon dioxide and oxygen, leading to the significant difference in total length of mechanical ventilation between the two groups. The two ends of the drainage strip were located outside the skin and were fixed, which facilitates observation. The treatment duration was shortened due to high efficiency of the operation. Nevertheless, this procedure raised the risk of infection and skin scarring.\u003c/p\u003e \u003cp\u003eThis study aims to provide a standard and effective drainage method for tension pneumomediastinum occurring from various causes, as well as to provide a reference for the treatment of tension pneumomediastinum caused by COVID-19. Clinicians should carefully consider the following points before selecting this method: familiarity with the local anatomical structure of the pre-tracheal region, as failure to accurately enter the pre-tracheal space will lead to ineffective operation; the method has the risks of damaging the trachea and increasing the infection routes.\u003c/p\u003e \u003cp\u003eRespiratory function improvements could not be completely attributed to drainage of the tension pneumomediastinum, as the treatment of primary diseases such as pneumonia and respiratory distress syndrome also resulted in gas absorption. The contribution of drainage could not be accurately determined since the sample size was too small and additional control groups were lacking, affecting the accuracy of the conclusion.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eOur method for draining tension pneumomediastinum improved respiratory function and shortened the length of stay in PICU. However, further studies are required to confirm these findings.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eSTROBE: Strengthening the Reporting of Observational Studies in Epidemiology; PICU: Pediatric Intensive Care Unit; pO2: pressure of oxygen; pCO2: pressure of carbon dioxide\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eEthics approval and consent to participate\u003c/h2\u003e\n\u003cp\u003eThe authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The trial was conducted in accordance with the Declaration of Helsinki (as revised in 2013). The study was approved by Guangdong Women and Children Hospital Medical Ethics Committee (No. 202001190) and informed consent was taken from all individual participants.\u003c/p\u003e\n\u003ch2\u003eConsent for publication\u003c/h2\u003e\n\u003cp\u003eInformed consent was obtained from the legal parent or guardian of each child. All the parents and guardians consented to the publication of their data.\u003c/p\u003e\n\u003ch2\u003eAvailability of data and materials\u003c/h2\u003e\n\u003cp\u003eTechnical appendix, statistical code, and dataset available from the FigShare repository, https://doi.org/10.6084/m9.figshare.13487295.\u003c/p\u003e\n\u003ch2\u003eCompeting interests\u003c/h2\u003e\n\u003cp\u003eThe authors declare that they have no conflicts of interest.\u003c/p\u003e\n\u003ch2\u003eFunding\u003c/h2\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003ch2\u003eAuthors\u0026apos; contributions\u003c/h2\u003e\n\u003cp\u003eQLL made the conception and design of the study, performed the operations, drafted the manuscript, and made data analysis and interpretation. CH and ZZH gave administrative support. All authors collected all data independently and checked the data against each other. All authors contributed to the critical revision of the manuscript, and approved its final form.\u003c/p\u003e\n\u003ch2\u003eAcknowledgements\u003c/h2\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAndrew E, Newcomb C, Peter Clarke. Spontaneous pneumomediastinum: a benign curiosity or a significant problem? Chest. 2005 Nov;128(5):3298\u0026ndash;302. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1378/chest.128.5.3298\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDesai A, Caldwell C, Hirschl D, et al. TENSION PNEUMOMEDIASTINUM IN A PATIENT WITH COVID-19 PNEUMONIA. Chest. 2020;158(4):A1028. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.chest.2020.08.955\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCampisi A, Poletti V, Ciarrocchi AP, et al. Tension pneumomediastinum in patients with COVID-19. Thorax. 2020;75(12):1130\u0026ndash;1. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1136/thoraxjnl-2020-215012\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKouritas VK, Papagiannopoulos K, Lazaridis G, et al. Pneumomediastinum J Thorac Dis. 2015;7(S1):44\u0026ndash;9. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.3978/j.issn.2072-1439.2015.01.11\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMCNICHOLL B. Pneumomediastinum and subcutaneous emphysema in status asthmaticus, requiring surgical decompression. Archives of disease in childhood 1960;35(182), 389\u0026ndash;392. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1136/adc.35.182.389\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAbu-Omar Y, Catarino PA. Progressive subcutaneous emphysema and respiratory arrest. J R Soc Med. 2002 Feb;95(2):90\u0026ndash;1. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1258/jrsm.95.2.90\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eO'Reilly P, Chen HK, Wiseman R. Management of extensive subcutaneous emphysema with a subcutaneous drain. Respirol Case Rep. 2013 Dec;1(2):28\u0026ndash;30. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1002/rcr2.9\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eClancy DJ, Lane AS, Flynn PW, et al. Tension pneumomediastinum: A literal form of chest tightness. Journal of the Intensive Care Society. 2017;18(1):52\u0026ndash;6. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1177/1751143716662665\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHajian-Tilaki K. Sample size estimation in epidemiologic studies. Caspian J Intern Med. 2011;2(4):289\u0026ndash;98.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWells FC, Coonar AS. Anatomy of the Mediastinum. Thoracic Surgical Techniques. Springer, Cham 2018:pp.\u0026nbsp;187\u0026ndash;90. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/978-3-319-66270-1_44\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"drainage, pneumomediastinum, mediastinum","lastPublishedDoi":"10.21203/rs.3.rs-275805/v2","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-275805/v2","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Pneumomediastinum is an emergency pediatric disease. A severe tension pneumomediastinum can result in respiratory and circulatory dysfunction. However, few papers describe surgical methods to treat tension pneumomediastinum in a normative manner.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eWe did a case-control study of 104 pediatric patients with tension pneumomediastinum and comorbid type II respiratory failure. Fifty-two patients were treated with a drainage strip being inserted into the pre-tracheal space while other 52 patients were treated without drainage. Arterial blood pO2 and pCO2 after 30 minutes and 12 hours of mechanical ventilation, chest radiography results after 12 hours of mechanical ventilation, and the length of stay in PICU of the two groups were analyzed by paired t-tests and Chi-square.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e Chest radiography after 12 hours of mechanical ventilation showed that the pneumomediastinum basically disappeared in the surgery group but did not decrease significantly in the control group. The arterial blood pCO\u003csub\u003e2\u003c/sub\u003e after 12 hours of mechanical ventilation and the length of stay in PICU were significantly lower in the surgery group than in the control group (p\u0026lt;0.001, p\u0026lt;0.001), while the arterial blood pO\u003csub\u003e2\u003c/sub\u003e after 12 hours of mechanical ventilation was significantly higher in the surgery group than in the control group (p\u0026lt;0.001). There were no significant intergroup differences in other variables. No recurrence occurred in either group during 7–14 days after discharge, and all patients recovered.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e Our method for draining tension pneumomediastinum improved respiratory function and shortened the length of stay in PICU.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eTrial registration:\u003c/strong\u003e ChiCTR2000039496. \u003cstrong\u003eDate of registration\u003c/strong\u003e: 2021/2/25 (retrospectively registered).\u003c/p\u003e","manuscriptTitle":"Inserting a Drainage Strip into the Pre-tracheal Space to Treat Tension Pneumomediastinum: A Case-control Study","msid":"","msnumber":"","nonDraftVersions":[{"code":2,"date":"2021-09-17 14:46:21","doi":"10.21203/rs.3.rs-275805/v2","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}},{"code":1,"date":"2021-03-05 16:41:22","doi":"10.21203/rs.3.rs-275805/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"e5c6cbcd-fe9e-4224-b0d7-e5ceca823886","owner":[],"postedDate":"September 17th, 2021","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":7252576,"name":"Pediatrics"}],"tags":[],"updatedAt":"2021-09-18T15:49:35+00:00","versionOfRecord":[],"versionCreatedAt":"2021-09-17 14:46:21","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v2","identity":"rs-275805","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-275805","identity":"rs-275805","version":["v2"]},"buildId":"_2-kVJe1T_tPrBINL-cwx","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}