The recent consensus statement from the faculty of prehospital care stated prevalence of tension pneumothorax which is misleading and up to 20 times higher than that which might be seen by the standard prehospital care practitioner.¹ Further analysis of the two references used for this statement is given and it can be seen that their results should not be extrapolated to the general prehospital environment without qualification.

Coats described tension pneumothorax in up to 5.4% of patients, 64% of whom were ventilated. They were also a major trauma subgroup.²

McPherson looked retrospectively at US soldier fatalities in Vietnam—when there was no prehospital chest decompression.³ His abstract and discussion, however, misrepresent the figures stated in his results and the study has methodological flaws. Accepting these flaws though, he observed that fatal tension pneumothorax may have occurred in up to 0.3% of American casualties (26/7801) and 3.9% of casualties who died with signs of a chest wound (26/663). Despite its flaws, the McPherson's paper may be more applicable to the average prehospital clinician as it looks purely at awake patients.

However, the external validity of both these papers (which look at high risk groups) to prehospital clinicians seeing a predominance of blunt trauma, awake patients should be questioned. The inference that should be taken away by the reader is that “fatal tension pneumothorax is very unlikely to occur in more than 0.3% of awake patients encountered in pre‐hospital care”. Even this is probably too high, but may go some way to stemming the tide of iatrogenic, needle induced pneumothorax.