Objective:We hypothesized that open bronchi within target pulmonary lesions are associated with percutaneous transthoracic needle biopsy (PTNB)-related hemoptysis.We sought to analyze and compare patient characteristics and target features as well as biopsy-related factors between patients with and without PTNB-related hemoptysis.Materials and Methods: We retrospectively analyzed 1484 patients (870 males and 614 females; median age, 66 years) who had undergone 1569 cone-beam CT (CBCT)-guided PTNBs.Patient characteristics (sex, age, and pathologic diagnosis), nodule features (nodule type, size, location, and presence of an open bronchus in target nodules), and biopsy-related factors (biopsy needle size, pleura-to-target distance, blood test results, open bronchus unavoidability [OBU] index, etc.) were investigated.OBU index, which was assessed using the pre-procedural CBCT, was a subjective scoring system for the probability of needle penetration into the open bronchus.Univariate analysis and subsequent multivariate logistic regression analysis were conducted to reveal the independent risk factors for PTNB-related hemoptysis.For a subgroup of nodules with open bronchi, a trend analysis between the occurrence of hemoptysis and the OBU index was performed.Results: The independent risk factors for hemoptysis were sex (female; odds ratio [OR], 1.918; p < 0.001), nodule size (OR, 0.837; p < 0.001), open bronchus (OR, 2.101; p < 0.001), and pleura-to-target distance (OR, 1.135; p = 0.003).For the target nodules with open bronchi, a significant trend between hemoptysis and OBU index (p < 0.001) was observed. Conclusion:An open bronchus in a biopsy target is an independent predictor of hemoptysis, and careful imaging review may potentially reduce PTNB-related hemoptysis.
Although chest CT has been discussed as a first-line test for coronavirus disease 2019 (COVID-19), little research has explored the implications of CT exposure in the population. To review chest CT protocols and radiation doses in COVID-19 publications and explore the number needed to diagnose (NND) and the number needed to predict (NNP) if CT is used as a first-line test.We searched nine highly cited radiology journals to identify studies discussing the CT-based diagnosis of COVID-19 pneumonia. Study-level information on the CT protocol and radiation dose was collected, and the doses were compared with each national diagnostic reference level (DRL). The NND and NNP, which depends on the test positive rate (TPR), were calculated, given a CT sensitivity of 94% (95% confidence interval [CI]: 91%-96%) and specificity of 37% (95% CI: 26%-50%), and applied to the early outbreak in Wuhan, New York, and Italy.From 86 studies, the CT protocol and radiation dose were reported in 81 (94.2%) and 17 studies (19.8%), respectively. Low-dose chest CT was used more than twice as often as standard-dose chest CT (39.5% vs.18.6%), while the remaining studies (44.2%) did not provide relevant information. The radiation doses were lower than the national DRLs in 15 of the 17 studies (88.2%) that reported doses. The NND was 3.2 scans (95% CI: 2.2-6.0). The NNPs at TPRs of 50%, 25%, 10%, and 5% were 2.2, 3.6, 8.0, 15.5 scans, respectively. In Wuhan, 35418 (TPR, 58%; 95% CI: 27710-56755) to 44840 (TPR, 38%; 95% CI: 35161-68164) individuals were estimated to have undergone CT examinations to diagnose 17365 patients. During the early surge in New York and Italy, daily NNDs changed up to 5.4 and 10.9 times, respectively, within 10 weeks.Low-dose CT protocols were described in less than half of COVID-19 publications, and radiation doses were frequently lacking. The number of populations involved in a first-line diagnostic CT test could vary dynamically according to daily TPR; therefore, caution is required in future planning.Coronavirus disease 2019 (이하 COVID-19) 폐렴에서 CT를 일차 진단 검사로 사용하고자 하는 논의가 있지만, 대규모 인구에게 CT 검사를 적용했을 때의 상황을 고찰한 연구는 없었다. 본 연구에서는 COVID-19 폐렴을 다룬 연구들에서 CT 프로토콜과 방사선량을 분석하고, CT 검사가 일차 진단 검사법으로 사용될 때 필요한 CT 검사량에 대해 알아보고자 한다.본 연구는 9개의 인용도가 높은 영상의학과 저널에서 COVID-19 폐렴의 CT 기반 진단을 다룬 문헌들을 검색하였다. 먼저, 연구에서 제시된 CT 프로토콜, 방사선량을 조사하여, 이를 해당 국가의 diagnostic reference level과 비교하였다. 추가로, COVID-19에 대한 CT 민감도 94%, 특이도 37%를 적용하여, 우한시와 뉴욕, 이탈리아의 초기 COVID-19 outbreak에서 polymerase chain reaction (이하 PCR) 검사 양성률에 기반한 number needed to diagnose (이하 NND)와 number needed to predict (이하 NNP)를 계산하였다.총 86개의 연구가 검색되었고, 그중 CT 프로토콜은 81개의 연구에서(94.2%), 방사선량은 17개의 연구에서(19.8%) 보고되었다. 저선량 흉부 CT는 표준선량 흉부 CT보다 2배 많은 연구에서 활용되었다(39.5% vs. 18.6%). 방사선량을 보고한 17개의 연구들 중, 15개의 연구에서 방사선량은 해당 국가의 diagnostic reference level 수치보다 낮았다(88.2%). COVID-19에 대한 CT 민감도 94%, 특이도 37%를 적용하였을 때, NND는 3.2회 CT scans으로 나타났다. 한편, PCR 검사 양성률 50%, 25%, 10%, 5%에서의 한 명의 COVID-19 환자를 진단 위한 CT 검사량을 나타내는 NNP는 각각 2.2, 3.6, 8.0, 15.5회의 CT scans로 나타났다. 우한시에서는 최종 17365명의 COVID-19 환자를 진단하기 위하여 약 35418명에서(PCR 검사 양성률 58%) 44840명(PCR 검사 양성률 38%)의 사람들이 CT 검사를 받은 것으로 나타났다. 뉴욕시와 이탈리아의 초기 COVID-19 유행 10주간, PCR 검사 양성률에 따라 일 CT 검사량이 최대 5.4, 10.9배까지 변화하였다.CT를 COVID-19에 대한 일차적인 진단검사로 사용할 경우, PCR 검사 양성률에 따라 CT 검사량은 변동량이 크고, 이는 추후 판데믹 상황에서 고려되어야 할 것이다.
We conducted a meta-analysis to determine a practical observation time for detecting a biphasic reaction after resolution of the initial anaphylactic reaction.A systematic literature search identified studies on adult patients with anaphylaxis and a subsequent biphasic reaction due to various causes that contained sufficient data to extract outcomes. The outcomes were pooled using a random-effects model.Twelve studies with a total of 2,890 adult patients with anaphylaxis and 143 patients with a biphasic reaction were included. In terms of the pooled negative predictive value, 1 h of observation achieved a 95.0% negative predictive value and ≥6 h of observation provided a 97.3% negative predictive value (95% CI: 95.0-98.5). The negative predictive value for a biphasic reaction increased with a longer observation time after initial anaphylaxis, and the increasing trend slowed down from 6 h of observation time. The pooled additional incidence rates of biphasic reactions per 100 person-hours after 1- and 4-h observations were 0.45 (95% CI: 0.20-1.04) and 0.41 (95% CI: 0.19-0.87), respectively. After > 8-12 h of postanaphylactic observation, the negative predictive value reached > 98%, while the additional incidence per 100 person-hours was < 0.10.An observation time of ≥6 h after resolution of an initial anaphylaxis symptom can exclude recurrence of a secondary reaction in > 95% of patients. Although longer observation periods resulted in the detection of more biphasic reactions, 6-12 h of observation time would be practical, supporting current relevant guidelines.