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Pneumomediastinum: an unusual radiographic finding following mid-facial trauma injury
Injury Vol. 28, No. 3, pp. 229-230,1997 0 1997 Elsevier Science Ltd. All rights reserved Printed in Great Britain 0020-1383/97
ELSEVIER
$17.00+0.00
PII: SOO20-1383(96)00179-9
Pneumomediastinum: an unusual radiographic finding following mid-facial trauma injury M. Ashley’
and C. Jones2
‘Retistrar in Restorative Dent&v, Uni‘t, Walton Hospital, Liverpool: Injury,
Vol. 28, No. 3,229-230,
Charles Cliiford UK
Dental Hospital,
the left naso-orbital region (Figure 1). Surgical emphysema
1997
Introduction Pneumomediastinum following injury is usually caused by severe thoracic injury, resulting in perforation of the trachea, bronchus, lung, oesophagus or an intra-abdominal viscus. Resulting free air within the tissues may then ascend via the subcutaneous space and fascial planes to produce cervical and facial emphysema. There are only three reported cases in which the reverse had occurred, whereby free intrathoracic air is secondary to cervicofacial emphysema. The proximity of the orbit to the paranasal air sinuses means that fractures in this region are particularly likely to result in surgical emphysema. We report a case in which this phenomenon resulted in a pneumomediastinum.
Case report A 23-year-old man presented at the Accident and Emergency department following an alleged assault in which he had been struck about the head and face. Clinical and radiographic examination revealed a depressed fracture of
Figure 1. Occipitomental
radiograph
Sheffield, UK and 2Regional Maxillo-Facial
showing
a displaced
fracture
was palpable around the left eye and cheek, and extended down both sides of the neck. The patient stated that this swelling had developed rapidly after he had blown his nose in an attempt to clear it of blood. There was no dyspnoea or tachypnoea and examination of the cardiovascular and respiratory systems was normal. However, in view of the surgical emphysema, a chest radiograph was performed to exclude pneumothorax. No pneumothorax was seen, but a marked pneumomediastinum was clearly visible (Figure 2). A course of intravenous Amoxycillin was commenced to reduce the risk of mediastinitis. The naso-orbital fracture was elevated uneventfully 3 days later under a general anaesthetic. Nitrous oxide and positive pressure ventilation were avoided because of the theoretical risk of further expanding the pneumomediastinum and creating a pneumothorax. A further chest radiograph taken 3 days postoperatively showed partial resolution of the pneumomediastinum.
Discussion Cervicofacial emphysema is a well-documented entity for which there are several proposed aetiolo-
in the left naso-orbital
region.
230
Injury: International Journal of the Care of the Injured Vol. 28, No. 3,1997
Figure 2. Postero-anteriorchestradiograph showing the pneumomediastinum.
gies. Iatrogenic causes of subcutaneous emphysema in the head and neck include use of compressed air syringes during endodontic procedures and surgical extractions performed with an air turbine drill. More frequently, air in the cervical and facial tissues results from facial injuries and surgery’“. It has been observed that nose blowing is a precipitating factor in the production of subcutaneous emphysema in multiple facial fractures. The sudden forced expiration that accompanies nose blowing results in high pressure in the upper airways. Air is thus forced into the tissues via mucoperiosteal tears related to the fractures in the bones of the paranasal air sinuses. The prevertebral fascia, the pretracheal fascia and the carotid sheath delineate the cervicothoracic compartment. Air forced into the tissues adjacent to the paranasal air sinuses, can spread from the retropharyngeal space, into the pterygomandibular space and via this cervicothoracic compartment, into the superior mediastinum4. Subcutaneous cervical emphysema may be easily diagnosed by the appearance of facial and cervical swelling with characteristic crepitation of the neck and supraclavicular areas. Pneumomediastinum may present with retrosternal pain radiating to the back, neck and shoulders, which may be exacerbated by swallowing. A loud grating sound (Hamman’s sign) synchronous with the heart may be heard over the left hemithorax in approximately 50 per cent of cases. A postero-anterior chest radiograph will reveal a sharp distinct line parallel with the left hilum and often the heart border representing a displacement of the mediastinal pleura. The ECG recording is usually normal but may reveal non-specific T-wave inversions, S-T segment deviation and shifts in the axis in about 25 per cent of cases5. The symptoms of subcutaneous emphysema and pneumomediastinum are generally self-limiting and eventually subside with non-operative management.
However, serious circulatory consequences can develop if increasing tension within the mediastinum causes a tamponading effect -with a subsequent decrease in cardiac output. This case describes that pneumomediastinum can occur as a complication of mid-facial injury, emphasizes the need to instruct patients not to blow their nose for some time after facial injury or surgery and that prophylactic antibiotics should be given.
References 1 Heslop
I. Surgical
emphysema
of the face, neck and
upper thoracir wall associatedwith a fracture of the facial skeleton. Br f Plast Suvg 1956; 8: 243. Tofield JJ. Pneumomediastinum following fracture of the maxillary antrum. Br J Plast Surg 1977; 30: 79. Almog Y, Mayron Y, Weiss J, Lazar M and Arahami E. Pneumomediastinum following blowout fracture of the medial orbital wall: a case report. Ophfhal Plust Reconstr Surg 1993; 9: 289. Williams P, Warnick R, Dyson M and Bannister L, eds. Gray’s Anatomy, 37th Ed. Edinburgh: Churchill Livingstone, 1989, pp. 582-3. Weatherall DJ, Ledingham JGG and Warrell DA, eds. Oxford Textbook of Medicine, 2nd Ed. Oxford: Oxford University Press, 1987, pp. 1129-30.
Paper
accepted
4 November
1996.
Requests for reprints should be addressed to: Mr Carl Jones, Senior Registrar, Regional Maxillo-Facial Unit, Walton Hospital, Rice Lane, Liverpool L9 lAE, UK.
ELSEVIER
$17.00+0.00
PII: SOO20-1383(96)00179-9
Pneumomediastinum: an unusual radiographic finding following mid-facial trauma injury M. Ashley’
and C. Jones2
‘Retistrar in Restorative Dent&v, Uni‘t, Walton Hospital, Liverpool: Injury,
Vol. 28, No. 3,229-230,
Charles Cliiford UK
Dental Hospital,
the left naso-orbital region (Figure 1). Surgical emphysema
1997
Introduction Pneumomediastinum following injury is usually caused by severe thoracic injury, resulting in perforation of the trachea, bronchus, lung, oesophagus or an intra-abdominal viscus. Resulting free air within the tissues may then ascend via the subcutaneous space and fascial planes to produce cervical and facial emphysema. There are only three reported cases in which the reverse had occurred, whereby free intrathoracic air is secondary to cervicofacial emphysema. The proximity of the orbit to the paranasal air sinuses means that fractures in this region are particularly likely to result in surgical emphysema. We report a case in which this phenomenon resulted in a pneumomediastinum.
Case report A 23-year-old man presented at the Accident and Emergency department following an alleged assault in which he had been struck about the head and face. Clinical and radiographic examination revealed a depressed fracture of
Figure 1. Occipitomental
radiograph
Sheffield, UK and 2Regional Maxillo-Facial
showing
a displaced
fracture
was palpable around the left eye and cheek, and extended down both sides of the neck. The patient stated that this swelling had developed rapidly after he had blown his nose in an attempt to clear it of blood. There was no dyspnoea or tachypnoea and examination of the cardiovascular and respiratory systems was normal. However, in view of the surgical emphysema, a chest radiograph was performed to exclude pneumothorax. No pneumothorax was seen, but a marked pneumomediastinum was clearly visible (Figure 2). A course of intravenous Amoxycillin was commenced to reduce the risk of mediastinitis. The naso-orbital fracture was elevated uneventfully 3 days later under a general anaesthetic. Nitrous oxide and positive pressure ventilation were avoided because of the theoretical risk of further expanding the pneumomediastinum and creating a pneumothorax. A further chest radiograph taken 3 days postoperatively showed partial resolution of the pneumomediastinum.
Discussion Cervicofacial emphysema is a well-documented entity for which there are several proposed aetiolo-
in the left naso-orbital
region.
230
Injury: International Journal of the Care of the Injured Vol. 28, No. 3,1997
Figure 2. Postero-anteriorchestradiograph showing the pneumomediastinum.
gies. Iatrogenic causes of subcutaneous emphysema in the head and neck include use of compressed air syringes during endodontic procedures and surgical extractions performed with an air turbine drill. More frequently, air in the cervical and facial tissues results from facial injuries and surgery’“. It has been observed that nose blowing is a precipitating factor in the production of subcutaneous emphysema in multiple facial fractures. The sudden forced expiration that accompanies nose blowing results in high pressure in the upper airways. Air is thus forced into the tissues via mucoperiosteal tears related to the fractures in the bones of the paranasal air sinuses. The prevertebral fascia, the pretracheal fascia and the carotid sheath delineate the cervicothoracic compartment. Air forced into the tissues adjacent to the paranasal air sinuses, can spread from the retropharyngeal space, into the pterygomandibular space and via this cervicothoracic compartment, into the superior mediastinum4. Subcutaneous cervical emphysema may be easily diagnosed by the appearance of facial and cervical swelling with characteristic crepitation of the neck and supraclavicular areas. Pneumomediastinum may present with retrosternal pain radiating to the back, neck and shoulders, which may be exacerbated by swallowing. A loud grating sound (Hamman’s sign) synchronous with the heart may be heard over the left hemithorax in approximately 50 per cent of cases. A postero-anterior chest radiograph will reveal a sharp distinct line parallel with the left hilum and often the heart border representing a displacement of the mediastinal pleura. The ECG recording is usually normal but may reveal non-specific T-wave inversions, S-T segment deviation and shifts in the axis in about 25 per cent of cases5. The symptoms of subcutaneous emphysema and pneumomediastinum are generally self-limiting and eventually subside with non-operative management.
However, serious circulatory consequences can develop if increasing tension within the mediastinum causes a tamponading effect -with a subsequent decrease in cardiac output. This case describes that pneumomediastinum can occur as a complication of mid-facial injury, emphasizes the need to instruct patients not to blow their nose for some time after facial injury or surgery and that prophylactic antibiotics should be given.
References 1 Heslop
I. Surgical
emphysema
of the face, neck and
upper thoracir wall associatedwith a fracture of the facial skeleton. Br f Plast Suvg 1956; 8: 243. Tofield JJ. Pneumomediastinum following fracture of the maxillary antrum. Br J Plast Surg 1977; 30: 79. Almog Y, Mayron Y, Weiss J, Lazar M and Arahami E. Pneumomediastinum following blowout fracture of the medial orbital wall: a case report. Ophfhal Plust Reconstr Surg 1993; 9: 289. Williams P, Warnick R, Dyson M and Bannister L, eds. Gray’s Anatomy, 37th Ed. Edinburgh: Churchill Livingstone, 1989, pp. 582-3. Weatherall DJ, Ledingham JGG and Warrell DA, eds. Oxford Textbook of Medicine, 2nd Ed. Oxford: Oxford University Press, 1987, pp. 1129-30.
Paper
accepted
4 November
1996.
Requests for reprints should be addressed to: Mr Carl Jones, Senior Registrar, Regional Maxillo-Facial Unit, Walton Hospital, Rice Lane, Liverpool L9 lAE, UK.