Trauma-related pneumopericardium: A literature review Nasr AO, Alsadery H, Osman A, Alblowi A, Bamalan O, Alshaikhi A, Alosaimi N, ElGhoneimy Y, Nabri MA

REVIEW ARTICLE

Year : 2023 | Volume : 12 | Issue : 1 | Page : 1-6

Trauma-related pneumopericardium: A literature review

Ayman O Nasr¹, Humood Alsadery², Adel Osman¹, Abdulrahman Alblowi², Omar Bamalan², Ahmed Alshaikhi², Nader Alosaimi², Yasser ElGhoneimy³, Mamoun A Nabri¹
¹ Department of Surgery, Trauma Unit, King Fahad Hospital of the University, Khobar; Department of Surgery, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
² Department of Surgery, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
³ Department of Surgery, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam; Department of Surgery, Cardiac Surgery Unit, King Fahad Hospital of the University, Khobar, Saudi Arabia

Date of Submission	05-Dec-2022
Date of Decision	08-Jan-2023
Date of Acceptance	11-Jan-2023
Date of Web Publication	15-Mar-2023

Correspondence Address:
Ayman O Nasr
Department of Surgery, Trauma Unit, King Fahad Hospital of the University, Khobar 31952
Saudi Arabia

Source of Support: None, Conflict of Interest: None

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DOI: 10.4103/sjhs.sjhs_146_22

Abstract

Trauma-related pneumopericardium (TRPP) is the collection of air in the pericardial space secondary to trauma, potentially leading to tension pneumopericardium (TPP) in which the entrapment of air generates sufficient pressure to compromise cardiac output leading to a life-threatening cardiac tamponade and circulatory failure. We aim to classify the diagnostic and therapeutic approaches of TRPP and the causes of the subsequent development of TPP. A computer-based search of all published reports on TRPP in the medical literature from database inception to March 2020, on MEDLINE, Ovid, and Scopus; analyzing the data regarding initial status at presentation, extent of injuries, diagnostic and treatment measures with the intention to have an understanding of the clinical behavior and management outcomes of TRPP. The search identified 84 published case reports of 105 patients with TRPP. In conclusion, TRPP leading to TPP is described in the literature as a condition that involves a young male who is subjected to blunt trauma, most commonly in a motor vehicle collision, presenting as a polytrauma patient in a state of shock and low systolic blood pressure, or possibly in cardiac arrest. In addition, he might have a tracheobronchial injury with or without pneumothorax or pneumomediastinum and might require mechanical ventilation.

Keywords: Pneumopericardium, simple, tamponade, tension and simple pneumopericardium, trauma, traumatic

How to cite this article:
Nasr AO, Alsadery H, Osman A, Alblowi A, Bamalan O, Alshaikhi A, Alosaimi N, ElGhoneimy Y, Nabri MA. Trauma-related pneumopericardium: A literature review. Saudi J Health Sci 2023;12:1-6

How to cite this URL:
Nasr AO, Alsadery H, Osman A, Alblowi A, Bamalan O, Alshaikhi A, Alosaimi N, ElGhoneimy Y, Nabri MA. Trauma-related pneumopericardium: A literature review. Saudi J Health Sci [serial online] 2023 [cited 2023 Jun 9];12:1-6. Available from: https://www.saudijhealthsci.org/text.asp?2023/12/1/1/371710

Introduction

Pneumopericardium was first described in 1844 by Bricheteau and labeled as a clinical entity in 1855 by Stokes.^[1] Simple pneumopericardium or nontension pneumopericardium (NTPP) is the collection of air in the pericardial space most commonly due to trauma.^[2] Trauma-related pneumopericardium (TRPP) was described in 1931 by Shackleford^[3] and delayed formation of TRPP was reported in 1966, causes of NTPP include mechanical ventilation, iatrogenic perforation, pericardial space infection, and perforation of a hollow viscus in the pericardial space were also reported.^[4] Tension pneumopericardium (TPP) is a severe form of pneumopericardium that occurs due to the entrapment of gas in the pericardial space generating sufficient pressure to compromise cardiac output leading to a life-threatening cardiac tamponade and circulatory failure.^[5] TPP is documented to take place 24 h after trauma resulting in a delayed or missed intervention with a fatal outcome in some reports.^[6],[7] The diagnosis and appropriate management of TPP remain a clinical challenge for trauma care front liners. The aim of this review is to assess and compare the different diagnostic and therapeutic approaches of TRPP and subsequent development of TPP.

Methodology

This review was carried out following the PRISMA guidelines.^[8] The primary aim of the review is to assess and compare the diagnostic and therapeutic approaches of TRPP. Additional include the study of possible parameters related to the subsequent development of TPP. The main outcome of the data analysis was to compare the end result of TRPP in terms of mortality between TPP and NTPP and its relation to clinical behavior and management provided.

Literature search

An internet-based search of MEDLINE, Ovid, Web of Science, Science Direct, Scopus, Cochrane Database of Systematic Reviews, and Google Scholar databases was conducted on all published cases of TRPP in the literature, with or without tension, published from database inception to March 2020. Non-English literature was screened as well and translated into English when required. The search used pneumopericardium, trauma, traumatic, simple, tamponade, tension, and simple pneumopericardium, as isolated or combined search words.

Screening of the reports

A cross-check of all references documented in the retrieved reports was also performed to avoid any missing reports. Two authors in this review, after conducting the computer search, have exchanged the collected reports with another two authors for cross-review and validation of the inclusion criteria as well as all exclusion criteria of TRPP with or without the tamponade effect. Any TRPP case that was reported as a postmortem or in the form of a clinical study was excluded due to the lack of patients' details diagnostic data to identify TRPP with or without tension premortem. Murad tool for appraisal and application of evidence derived from case reports and case series was used in this review.^[9] After removing the duplicates, data on authors, report type, year of reported, number of cases reported, age, gender, initial status at presentation, extent of injuries, diagnostic and treatment tools used, factors related to the development of TPP, and management outcomes of TRPP were collected.

Data extraction and analysis

A descriptive analysis of the collected data was performed. Some continuous data are presented as categorical whenever cutoff levels are required to differentiate between two or more contrast groups of one data set as using systolic blood pressure (SBP) reading of 110 mmHg to be the cutoff point to categorize hypotensive and normotensive status of reported patients and heart rate of 100 bpm again to categorize stable and unstable reported patients. Categorical data such as gender, trauma type and cause, treatment type, and outcome were plotted in the form of ratios and percentages.

Results

The search identified 87 published case reports of 108 patients with TRPP.^{[2],[4],[5],[6],[7],[10],[11],[12],[13],[14],[15],[16],[17],[18],[19],[20],[21],[22],[23],[24],[25],[26],[27],[28],[29],[30],[31],[32],[33],[34],[35],[36],[37],[38],[39],[40],[41],[42],[43],[44],[45],[46],[47],[48],[49],[50],[51],[52],[53],[54],[55],[56],[57],[58],[59],[60],[61],[62],[63],[64],[65],[66],[67],[68],[69],[70],[71],[72],[73],[74],[75],[76],[77],[78],[79],[80],[81],[82],[83],[84]} After the exclusion of four reports mostly due to missing full text [Table 1], the total of 83 publications reporting 105 patients were included in this review [Figure 1].

Figure 1: Flow diagram of the literature search and reports screening of reports. TRPP: Trauma-related pneumopericardium, TPP: Tension pneumopericardium, NTPP: Nontension pneumopericardium

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Table 1: Case reports and patients excluded from the review

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Statistically, the patient's chance of cure is 45% with decompression alone, 23% after an operative intervention, and 7% after multiple treatment modalities, with an unfortunate mortality rate of 26% most probably not due to TPP.

Etiology and clinical presentation

TRPP predominantly affected young males with a male: female of 8.5:1 (90% males) and an age range of 3–75 years (mean 24.5). TPP occurred in 69 patients (65.7%), most of them are associated with polytrauma, 53 patients (77%) and only 16 patients developed TPP as a result of isolated chest trauma (25%). Blunt trauma was by far the most common cause of trauma-associated pneumopericardium accounting for (84%) in our review and in literature.^[85] Motor vehicle collision (MVC) represents the most common cause of TRPP (59%) followed by stab wounds (12%) and fall from height (13%). A preliminary calculation of the listed injuries for each patient shows that 81% of patients have a possible severe injury based on an expected injury severity score (ISS) >15 with only 5.7% missing data.

Half of the patients (53%) were reported to be stable at presentation (based on the documented vitals in the report at presentation, when available 49%–62% missing data, or on the report of the authors on the hemodynamic status of the patient at presentation), 17% were unstable and 13% developed cardiac arrest during their management [Table 2].

Table 2: Percentage of clinical findings at presentation for tension pneumopericardium and nontension pneumopericardium

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Dyspnea was the most common presenting symptom (35%) followed by chest pain (25%) and the combination of both symptoms, dyspnea and chest pain, occurred in 16% of patients. TRPP is recognized at the time of presentation in 75% of patients, two-third of them (67%) subsequently develop TPP. Seriously enough, TRPP developed in up to 24% of patients without initial evidence at presentation, one-fifth of them (20%) developed TPP, this is higher than a previously reported incidence of 9.5%.^[52] Pneumothorax was the most frequent injury associated with TRPP (71%) followed by pneumomediastinum (42%), central and subcutaneous emphysema (40%), fracture ribs (30%), tracheobronchial injury (9%), and sternal fracture (5%) [Table 3].

Table 3: Percentage of associated injuries at presentation for tension pneumopericardium and nontension pneumopericardium

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Diagnosis and management

The diagnosis of TRPP was predominantly established using a chest X-ray in 91% of patients. Computed tomography scan was introduced as a diagnostic tool in reports since 1994 onward.^[31] It was the test of choice in 52% of the patients with or without chest X-ray, especially in polytrauma patients. Bronchoscopy was required in 28% of patients to rule out tracheobronchial injuries.

Mechanical ventilation was required in 56% of patients, while only 35% of patients required pericardial decompression, and 23% required intercostal tube (ICT) drainage of the pleural space. The operative decompression was required in 17% of patients; conservative noninterventional approach was accomplished in 16% of patients. Combined therapy in the form of decompression plus ICT insertion or open pericardial approach was performed on 4 and 3% of patients, respectively. The vast majority of reported patients (81%) had complete resolution of their pneumopericardium, 18% died from different causes but not directly due to pneumopericardium and only 1% died as a direct sequel of TRPP [Table 4].

Table 4: Percentage of provided treatment approach and outcome for tension pneumopericardium and nontension pneumopericardium

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Discussion

The highest number of pneumopericardium in literature of all types was reported by Cummings et al.^[4] in 1984 reviewing 252 cases. Their 100-year incidence of TRPP was 62% of all pneumopericardium cases. Blunt trauma represents 85% of all TRPP consistent with our review of 84%. The incidence of penetrating trauma from three reviews (Cummings et al.,^[4] Demetriades et al.,^[86] and Nicol et al.^[87]) ranged between 8% and 15% which is again comparable to an incidence of 16% in our review. Trauma-related TPP is documented in 3 patients in Cummings et al.'s review, 1 in Nicol et al.'s review and 1 in Demetriades et al. review. Other causes such as mechanical ventilation, iatrogenic perforation, pericardial space infection, and perforation of a hollow viscus in the pericardial space are also reported.^[4]

Blunt trauma is proven to be by far the most common cause of trauma-associated pneumopericardium accounting for 84% in our review and in literature. MVC was reported as the most common blunt trauma modality^[47],[50] followed by falls from a great height which came in support of our findings for motor vehicle collision (MVC) being the most common cause accounting for 59% followed by fall from height with 13% incidence. The presence of myocardial, pericardial, or aortic trauma was taken as an indicator of a possible pneumopericardium^[85] in support of our findings.

Three possible passageways are described in literature regarding the pathophysiology of pneumopericardium and accumulation of air in the pericardial space in the absence of a direct communication/trauma. First is the escape of air from alveoli into the interstitial space along the pulmonary perivascular sheaths (the Macklin effect).^[88] Second is through a congenital pleuropericardial connection that can become active in the presence of a pneumothorax.^[32] Third is through disruption of the alveolar or pleuropericardial membrane that can lead to the development of a “one-way valve” allowing continued inflation of the pericardial sac without notable deflation.^[20] Technically, any of the three passages can occur as a result of blunt thoracic trauma, which in the presence of increased pleural pressure, as in positive pressure ventilation,^[14],[27] can push air into the pericardial space with a resultant pneumopericardium.^[12] On the other hand, penetrating chest trauma can cause a passageway through direct disruption of the pericardial sac, or indirectly through a disruption of the tracheobronchial, gastrointestinal, pleural, or mediastinal spaces.^[87]

Regardless of the mechanism and the site of disruption, air in the pericardial space can cause TPP and if there is a passageway to the pericardial sac, gas will continue to flow under enough pressure, resulting in a tamponade effect.^[14] The tamponade effect occurs when the venous pressure increases proportionately with further increase in the pericardial gas under pressure. Tamponade was developed under experimental environments when the intrapericardial pressure has exceeded 266 mm H₂O.^[89] Adcock et al.^[89] the experiment revealed that to maintain adequate hemodynamics, venous pressure should exceed pericardial pressure by 35 mm H₂O, Hymes et al.^[30] suggests less pressure difference exceeding 14.5 cm H₂O for tamponade to develop. Maurer et al.^[90] in 1958 as a result of similar experiments stated that the rate of air insufflation is a major factor in the production of cardiac tamponade. The risk of TPP was high in conditions such as blunt trauma, severe trauma with ISS >15, pneumothorax, pneumomediastinum, tracheobronchial injury, and the use of mechanical ventilation.

The conservative approach was more commonly associated with NTPP, resulting in a complete resolution in 42% of patients. Nonetheless, decompression commonly through a subxiphoid window was the most common approach for TPP accounting for 45% and 52% when combined with another modality such as ICT insertion or proceeding to open surgery. The direct operative treatment was required in 23% of TPP patients. The overall mortality was more commonly associated with TPP mainly related to the severity of trauma and the development of complications (e.g., sepsis or septic shock).

The most important limitations of the study are; the search only covered English literature which makes a missed non-English report of TRPP a possible limitation, moreover, the time variation in recording the initial vital signs based on which some conclusions regarding patients' initial haemodynamic status and stability were drawn could also represent a possible limitation in the drawn findings included in this review.

Conclusion

TRPP leading to TPP is described in literature as a condition that involves a young male with a mean age of 24 years who is subjected to a blunt trauma, most commonly MVC. He presents as a polytrauma patient with an ISS >15 in a state of shock and low SBP, could also present with cardiac arrest. He is likely to have a tracheobronchial injury with or without a pneumothorax or pneumomediastinum and very likely requires mechanical ventilation. He has a 45% chance of cure with decompression alone and a 23% chance of operative intervention to be cured and a 7% of having multiple treatment modalities to be cured. Unfortunately, he has a 26% chance to die mostly not due to TPP.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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