Occult pneumothoraces – red flag or red herring?

Abstract

Pneumothorax is a relatively common complication following blunt chest trauma; however, the investigation and management of these injuries remains a contentious issue. Occult pneumothoraces are those not diagnosed by conventional radiographic imaging, but by subsequent computed tomography. This review examines the current evidence base behind the investigation and management of this condition. An anteroposterior chest x-ray should not be underestimated in its ability to provide sufficient radiological information to instigate an initial management plan in the trauma setting. Ultrasound has a high diagnostic rate for pneumothoraces; however, it is subjected to influence from other injuries, whilst failing to address other important injuries in trauma patients requiring computed tomography imaging. It is therefore best used in situations where computed tomography is unavailable or contraindicated. In the management of occult pneumothoraces, there is little difference in patient outcome between those managed conservatively or with a prophylactic chest drain. Clinicians must be wary of recommendations which in this area are often based on inadequate study size and they should continue to provide the best individual care on a case-by-case basis. Observation alone in patients that are haemodynamically stable can be considered, with a view to drainage of the pneumothorax should the clinical status of the patient deteriorate.