Indications for computed tomography angiography in limb trauma.

INTRODUCTION

Computed tomography angiograms (CTAs) are useful in detecting vascular injury. There is a lack of consensus regarding the indications of CTAs in limb trauma, leading to overutilisation of CTAs in some centres and exposing patients to unnecessary harm. Thus, the aim of this study is to define the appropriate indications for CTAs in limb trauma.

METHODS

This is a retrospective cohort study of consecutive CTAs performed in a tertiary hospital from January to December 2022. Demographic and clinical factors were collected from the patients' charts including physical examination findings and arterial pressure index (API) measurements. Physical examination findings include hard signs (e.g. absent pulse) or soft signs (e.g. non-expanding haematoma). These data were analysed to detect correlation with vascular injury on the patient's CTA.

RESULTS

Forty-nine CTAs were included, of which 10 (20.4%) found vascular injury. Hard signs (P < 0.001) and an API <0.9 (P = 0.02) were significantly correlated with vascular injury. Hard signs had a sensitivity of 90% and specificity of 82%, whereas APIs had a specificity and sensitivity of 100%. Soft signs were not correlated with vascular injury due to poor specificity but had a sensitivity of 100%. Knee dislocations were not associated with vascular injury (P = 0.5).

CONCLUSION

This small study suggests that CTAs are indicated if there are hard signs of vascular compromise or an API <0.9, provided the patient is haemodynamically stable. The presence of soft signs can help identify which patients should receive an API measurement. CTAs may not be routinely indicated in knee dislocations.