Objective To discuss the clinical value of CT combined electronic level guided percutaneous transthoracic needle biopsy in diagnosis of small pulmonary nodules.Methods 44 cases of lung mini-nodule underwent CT combined electronic level guided percutaneous transthoracic needle biopsy.After operation the tissue was sent for pathologic examination.The nodules were divided into two groups,including Group A (diameter 0.5-1.0 cm,N=10) and Group B (diameter 1.1-2.0 cm,N=34),according to the different sizes of diameter.The excision of postoperative pathological and diagnosis result of clinical diagnosis and treatment of more than 12 months follow up were taken as the final result.The sensitivity,specificity,veracity and complications were compared and analyzed using paired x2 test,taking P＜0.05 as significant difference.Results (1)The arrival rate of target puncture were 100 ％ in 44 cases,with the sensitivity rate of 90.9％,specificity rate of 100 ％,veracity rate of 88.6 ％,positive predictive value of 97.5 ％,and negative predictive value of 100 ％.The sensitivity,specificity and veracity of Group A were 77.8％,100％ and 70.0％ respectively.And the sensitivity,specificity and veracity of Group B were 94.1％,100％ and 94.1％ respectively.The sensitivity,veracity of Group A was higher than Group B (P＜0.05),while there was no difference in specificity.(2)Complication:the incidence rate of pneumothorax,pulmonary bleeding symptoms and hemothorax were 9.1％,11.4％,2.3％,respectively.The incidence rate of total complication was 22.7％,and all be cured after the treatment.The lesions with emphysema around is a risk factor for pneumothorax and pulmonary bleeding symptoms (x2 =11.2,10.2,P＜0.05).However,the position,size and deepness was not correlated with the complications mentioned above (P ＞0.05).Conclusion CT combined electronic level guided percutaneous transthoracic needle biopsy is a safe,effective and accurate diagnostic method for lung mini-nodule lesion.

Objective To review the current research and application of root cause analysis (RCA) method in China's hospital management.Methods A retrospective analysis in six aspects was made by means of formulating a retrieval strategy and inclusion criteria, retrieval of databases, and literature review.Results The number of Chinese RCA researches was increasing year by year, mostly from researcher of the eastern coastal areas.These studies focused on the effects of RCA application outcomes and nursing safety.Tools in use were mainly fishbone diagram, brainstorming and 3-why method.72.24% of the root causes as found in literature were system factors, and 27.76% were human factors.Most of the researches made positive comments on RCA.Conclusions RCA is being warmly embraced by China's hospital management as it can positively change the accountability culture towards adverse events.Yet RCA has not been satisfactorily applied, and its future research and application in China's hospital management need more in-depth study and critical analysis.