In order to improve the efficacy of vibration expectoration and prevent secondary injury in patients with chest trauma,the body surface marking method was used in vibration expectoration.The exact injured locations and areas were identified via CT ot X-ray results.Then,the restricted and focused areas of expectoration were marked with red and green colors,which could guide the machines to avoid the fracture sites,reduce pain,prevent secondary injury and administrate effective expectoration in the areas of sputum and atelectasis.However,the dynamic CT or X-ray results must be used for reference to ensure the accuracy of the body surface marking.