Air bag safety in road traffic accidents
Authors: O'Donnell ME , McCaul D , Nazir M , McGuigan J 
Published: May 2014

Mr and Mrs W were admitted to the regional thoracic unit with sternal fractures following a head-on road traffic accident at a combined speed greater than 70 mph. Both were wearing lap–shoulder seat-belts, but only the driver's side had an air bag, which deployed normally on impact. They were assessed and treated according to the Royal College of Surgeons Advanced Trauma and Life Support guidelines at the crash site and transferred to the regional trauma centre for further assessment and treatment. Manual extraction from the vehicle was not required.

1. What further information from the paramedic team would be helpful in this situation?

Both Mr and Mrs W complained of severe retrosternal pain exacerbated by inspiration. No other complaints were noted. Both patients had normal Glasgow Coma Scales and remained haemodynamically stable. ach had bruising and marked tenderness over the sternum. Mr W had further bruising and tenderness over the right supraclavicular fossa but no other abnormality. Auscultation confirmed normal heart sounds, and satisfactory air entry to both lung fields without added sounds. The rest of the clinical assessment was unremarkable. Both patients were previously well and smoked (20/day).

2. What initial investigations would you request?

Haematological investigations were normal with haemoglobin concentrations of 14.4 g/dl and 13.9 g/dl respectively. Serum creatinine kinase was raised as expected but the myocardial band isoform remained normal. Twelve-hour serum troponin-1 was also normal. Electrocardiograph demonstrated normal sinus rhythm with no acute changes. The sternal view radiograph revealed sternal fractures in both individuals with increased displacement of the posterior table in Mr W's X-ray. Frontal radiograph of the chest performed in both patients did not reveal any evidence of rib fractures, pneumothorax or haemothorax.

3. What are the treatment options for both patients?

Both patients were treated conservatively with oral analgesia, inhaled nebulisers, chest physiotherapy and monitored by cardiac telemetry for 24 hours. Throughout the admission, Mr W complained of more severe sternal tenderness than his wife, who remained comfortable. He also complained of back pain. Repeat clinical examination showed soft tissue tenderness at the level of the thoracic vertebrae. Thoracic spinal X-rays demonstrated old crush fractures with no acute injury. No active intervention was required following orthopaedic assessment.

Mrs W was discharged well on day 3 and Mr W on day 4. Mr W was reviewed 2 weeks post-discharge complaining of persisting sternal pain. Clinical examination elicited sternal tenderness as before but also a firm swelling in the line of his seat belt at the right supraclavicular fossa. Ultrasound showed a resolving haematoma with no evidence of a traumatic false aneurysm. At 6-month review, Mrs W remained well but Mr W still complained of persistent sternal tenderness requiring regular oral analgesia. Check X-rays of both patients showed healing sternal fractures with no other abnormality. No other investigation or treatment was required and they were discharged.