Seven "NOs"

Q: Which seven "NOs" are required to safely forego CT imaging of the chest in adults with blunt thoracic trauma '?


Answer:  The NEXUS research group has validated 'decision instrument' (DI) to help determine which adults (more than 15 years old) with blunt thoracic trauma, within the last 24 hours, can safely forego CT imaging of the chest, with the major objective to reduce indiscriminate use of CT scans in ED. The first iteration of the NEXUS decision instrument included the following seven criteria

1. Age  more than 60 years
2. Chest pain 
3. Intoxication 
4. Abnormal mental status 
5. Chest wall tenderness 
6. Distracting painful injury 
7. Rapid deceleration mechanism (ie, fall of more than 20 feet, or Motor Vehicle Collision at more than 40 m/65 km/hour

There was also a subsequent iteration of the NEXUS decision instrument known as Chest CT-All, where criteria were updated with four replacements

1. Abnormal plain chest radiograph
2. Sternal tenderness
3. Thoracic spine tenderness 
4. Scapular tenderness
5. Chest wall tenderness 
6. Distracting painful injury 
7. Rapid deceleration mechanism (ie, fall of more than 20 feet, or Motor Vehicle Collision at more than 40 m/65 km/hour

Chest CT-All criteria have a variant known as "CT-Major", where even the 7th point was taken out!

References: 

1. Rodriguez RM, Anglin D, Langdorf MI, et al. NEXUS chest: validation of a decision instrument for selective chest imaging in blunt trauma. JAMA Surg 2013; 148:940. 

2. Rodriguez RM, Langdorf MI, Nishijima D, et al. Derivation and validation of two decision instruments for selective chest CT in blunt trauma: a multicenter prospective observational study (NEXUS Chest CT). PLoS Med 2015; 12:e1001883.