Pneumomediastinum, an unusual complication of facial trauma.

Abstract

Pneumomediastinum is often an incidental finding following a blunt or penetrating trauma to the neck or chest. We report a rare case of pneumomediastinum following an isolated facial trauma that was diagnosed on imaging. We also review the clinical signs of this condition, its' radiologic characteristics, and the 18 previously reported cases of pneumomediastinum following facial trauma.

Introduction

Pneumomediastinum usually occurs following an injury that causes a perforation of the trachea, bronchus, esophagus, or an abdominal-hollow viscus. Cases of pneumomediastinum caused by facial trauma that leads to subcutaneous cervicofacial emphysema and subsequent tracking of air into the mediastinum along fascial planes are extremely rare; in fact, to the best of our knowledge, only 18 cases have been previously recorded in the literature. (1-17) In this article, we report a new case.

Case report

A 25-year-old man who was undergoing parachute training in the British armed forces presented to the Accident and Emergency Department following an alleged assault in which he had been punched on the left side of the face. He had not lost consciousness, and he had not been struck anywhere else. The patient complained of left neck pain and some dysphagia.

Clinical examination revealed left periorbital ecchymosis and facial swelling, with palpable tactile crepitus secondary to surgical emphysema. Tenderness was noted in the left neck, but not cervical surgical emphysema. Auscultation of the heart and lungs revealed normal cardiac and breath sounds.

No fracture was seen on plain x-ray of the facial bones. Chest x-ray demonstrated mediastinal air with pneumo-pericardium, but no pneumothorax or fractured ribs (figure 1). Computed tomography (CT) demonstrated surgical emphysema of the left face and neck and a fracture through the anterior wall of the maxillary sinus (figure 2).

[FIGURE 1-2 OMITTED]

The patient was treated with intravenous antibiotics and discharged after 48 hours. He was grounded from flying because of the ambient pressure changes to which he would have been subjected. Fourteen days later, his surgical and mediastinal emphysema had completely resolved clinically, and he was discharged from hospital follow-up and cleared for return to duty.

Discussion

Mediastinal and cervical emphysema have rarely been reported in association with an isolated facial fracture.

Clinical features. The clinical features of pneumomediastinum are chest pain (which is retrosternal and usually pleuritic), dyspnea, dysphagia, and occasionally a feeling of constriction. The chest pain may be mild or severe, and it can radiate to the neck, back, shoulders, or down the arms; the pain is believed to be the result of dissection and distension in the fascial planes of the mediastinum. (9) Signs may be limited to cervical subcutaneous emphysema.

The apex beat may be impalpable, and cardiac dullness to percussion may be absent. Hamman's sign--a crunch-like sound heard over the left hemithorax that is accentuated during systole and expiration(18)--is present in approximately 50% of all cases of pneumomediastinunl. (7)

Radiolegic features. On plain chest x-ray, it is possible to see evidence of mediastinal air in any of several ways--via a thymic sail sign (thymus outlined by air), a tubular artery sign (air surrounding the pulmonary artery or either of its main branches), a double bronchial wall sign (air residing adjacent to a main bronchus that allows for a clear depiction of the bronchial wall), a continuous diaphragm sign (air trapped posterior to the pericardium, giving an appearance of a continuous collection of air on anteroposterior radiograph), and a pneulaopericardium (air anterior to the pericardium on a lateral film). (19) Pneumothorax is present in approximately 50% of cases of pneumomediastinum. (7)

Including ours, only 19 cases of pneumomediastinum secondary to an isolated facial trauma have been reported in the literature. (1-17) Most of these cases occurred in men aged 23 to 47 years, usually following a blunt trauma; some cases were also associated with blowing the nose (table). The facial injuries among the 19 patients included 11 fractures of the maxilla (57.9%), 10 orbital blowouts (52.6%), 6 fractured zygomas (31.6%), and 4 fractures of the mandible (21.1%). Pneumomediastinum has also been reported following minimal dental surgery and following the use of high-speed air turbine drills. (20)

In all 19 cases, the pneumomediastinum was treated conservatively with intravenous antibiotics, and spontaneous resolution was seen within a few days. No further treatment was necessary for any of the 19 patients.

In conclusion, pneumomediastinum is a rare but recognized complication of blunt facial trauma. In the absence of other injuries and following correct management of the facial injury, patients should be treated with rest and intravenous antibiotics and be told to refrain from blowing their nose. Spontaneous resolution of the mediastinal air occurs rapidly. This report aims to contribute to the literature in this field.

Table. Characteristics of the 19 reported cases of pneumomediastinum
secondary to facial trauma

Author                    Age/sex   Cause of injury

Habal et al, (1) 1972      45/F     Struck in face

Switzer et al, (2) 1974    35/M     Struck in face
                           36/M     Struck in face

Tofield, (3) 1977          27/M     Struck in face

Adendorff et               25/M     Struck in face
  al, (4) 1977                      w/blunt
                                    instrument

Cianchetti and             45/M     Gunshot in face
  Carroll, (5) 1980

Chawla et al, (6) 1984     33/M     Blunt trauma
                                    to face

Minton and Tu, (7) 1984    32/M     Struck in face

Lee et al, (8) 1987        50/F     Fell down stairs

Flood, (9) 1988            47/M     Struck in face
                                    w/steel bar

Andersen et                45/M     Struck in face
  al, (10) 1988

Carmichael et              40/M     Kicked in face
  al, (11) 1988

Haberkamp et al,           26/M     Struck in face
  (12) 1989

Henry and                  18/M     Traffic accident
  Hills, (13) 1989                  (no seatbelt)

Almog et al, (14) 1993     60/M     Struck in face

Kourtidou-Papadeli         43/M     Struck in face
  et al, (15) 1996                  (during flight)

Ashley and                 23/M     Struck in face
  Jones, (16) 1997

Abrahamian and             23/M     Struck in face
  Pollack, (17) 2000

Monksfield et              25/M     Struck in face
  al, * 2005

                                                                 Blown
Author                   Age/sex  Type of injury                 nose?

Habal et al, (1) 1972     45/F    Orbital blowout                 Yes

Switzer et al, (2) 1974   35/M    Fractured orbit, maxilla,
                                  and zygoma

                          36/M    Zygomaticomaxillary fracture

Tofield, (3) 1977         27/M    Orbital blowout and             Yes
                                  fractured maxilla

Adendorff et              25/M    Multiple fractures of
  al, (4) 1977                    mandible and maxilla

Cianchetti and            45/M    Gunshot wound in
  Carroll, (5) 1980               maxillary antrum

Chawla et al, (6) 1984    33/M    Fractured orbital wall
                                  and maxillary antrum

Minton and Tu, (7) 1984   32/M    Fractured mandible

Lee et al, (8) 1987       50/F    Zygomaticomaxillary fracture    Yes

Flood, (9) 1988           47/M    Fractured zygoma and
                                  maxillary antrum

Andersen et               45/M    Fractured orbital floor
  al, (10) 1988                   and nose

Carmichael et             40/M    Fractured zygoma                Yes
  al, (11) 1988

Haberkamp et al,          26/M    Fractured mandible
  (12) 1989

Henry and                 18/M    Fractured mandible and
  Hills, (13) 1989                maxilla; orbital blowout

Almog et al, (14) 1993    60/M    Orbital blowout
                                  (medial wall)

Kourtidou-Papadeli        43/M    Orbital blowout
  et al, (15) 1996

Ashley and                23/M    Fractured naso-orbital area     Yes
  Jones, (16) 1997

Abrahamian and            23/M    Fractured maxillary
  Pollack, (17) 2000              antrum, orbital floor,
                                  and zygomatic arch

Monksfield et             25/M    Fractured maxillary antrum
  al, * 2005

* Present case

References

(1.) Habal MB, Beart R, Murray JE. Mediastinal emphysema secondary to fracture of orbital floor. Am J Surg 1972;123:606-8.

(2.) Switzer P, Pitman RG, Fleming JP. Pneumomediastinum associated with zygomatico-maxillary fracture. J Can Assoc Radiol 1974;25:316-18.

(3.) Tofield JJ. Pneumomediastinum following fracture of the maxillary antrum. Br J Plast Surg 1977;30:179-81.

(4.) Adendorff D, Malherbe WD, Grotepass F. Generalized surgical emphysema as an early complication of facial fracture: A case report. S Afr Med J 1977;51:722-4.

(5.) Cianchetti JA, Carroll GF. Traumatic pneumomediastinum resulting from facial trauma. Ann Emerg Med 1980;9:218-21.

(6.) Chawla K, Steinbaum S, Alexander LL. Pneumomediastinum occurring in association with facial trauma. N Y State J Med 1984;84:9.

(7.) Minton G, Tu HK. Pneumomediastinum, pneumothorax, and cervical emphysema following mandibular fractures. Oral Surg Oral Med Oral Pathol 1984;57:490-3.

(8.) Lee HY, Samit A, Mashberg A. Extensive post-traumatic subcutaneous emphysema and pneumomediastinum following a minor facial injury. J Oral Maxillofac Surg 1987;45:812-15.

(9.) Flood TR. Mediastinal emphysema complicating a zygomatic fracture: A case report and review of the literature. Br J Oral Maxillofac Surg 1988;26:141-8.

(10.) Andersen C, Andersen C II, Rasmussen F. Pneumomediastinum associated with orbital fracture. Case report. Scand J Plast Reconstr Surg Hand Surg 1988;22:249-50.

(11.) Carmichael F, Ward-Booth RP, Banks JM. Pneumomediastinum after facial trauma. Oral Surg Oral Med Oral Pathol 1988;66:540-2.

(12.) Haberkamp TJ, Levine HL, O'Brien G. Pneumomediastinum secondary to a mandible fracture. Otolaryngol Head Neck Surg 1989;101:104-7.

(13.) Henry CH, Hills EC. Traumatic emphysema of the head, neck, and mediastinum associated with maxillofacial trauma: Case report and review. J Oral Maxillofac Surg 1989;47:876-82.

(14.) Almog Y, Mayron Y, Weiss J, et al. Pneumomediastinum following blowout fracture of the medial orbital wall: A case report. Ophthal Plast Reconstr Surg 1993;9:289-91.

(15.) Kourtidou-Papadeli C, Paspatis A, Mohler S. Pneumomediastinum during flight secondary to facial fractures--A case report. Aviat Space Environ Med 1996;67:1201-3.

(16.) Ashley M, Jones C. Pneumomediastinum: An unusual radiographic finding following mid-facial trauma injury. Injury 1997;28:229-30.

(17.) Abrahamian FM, Pollack CV. Traumatic pneumomediastinum caused by isolated blunt facial trauma: A case report. J Emerg Med 2000;19:43-6.

(18.) Munsell WP. Pneumomediastinum. A report of 28 cases and review of the literature. JAMA 1967;202:689-93.

(19.) Zylak CM, Standen JR, Barnes GR, Zylak CJ. Pneumomediastinum revisited. Radiographics 2000;20:1043-57.

(20.) Chen SC, Lin FY, Chang KJ. Subcutaneous emphysema and pneumomediastinum after dental extraction. Am J Emerg Med 1999;17:678-80.

From the Department of Otolaryngology, Radcliffe Infirmary (Dr. Monksfield, Dr. Whiteside, Dr. Steventon, and Dr. Milford), and the Department of Radiology, John Radcliffe Hospital (Dr. Jaffe), Oxford, U.K.

Reprint requests: Mr. Peter Monksfield, 17 Broadfern Rd., Knowle, Solihull B93 9DE, UK. Phone: [phone]; fax: [phone]; e-mail: [e-mail]