Association between radical versus conservative surgery and short-term outcomes of hepatic cystic echinococcosis in Nyingchi, China: a retrospective cohort study.

BACKGROUND: Radical or conservative surgical treatment for hepatic Cystic Echinococcosis (hepatic CE) is controversial. We aimed to measure the association between radical surgery (RS) versus conservative surgery (CS) and short-term outcomes in our cohort. METHODS: Medical records of hepatic CE patients' demographic, clinical, radiological, operative and postoperative details who underwent surgical treatment between January 3, 2017 and January 3, 2018 at the Department of General Surgery, Nyingchi People's Hospital, Nyingchi, China, were retrieved and analyzed. The primary outcome was overall morbidity. The secondary outcomes included: (i) bile leakage; (ii) complications of lung, pleura, heart, liver, pancreas and biliary tract; (iii) incision infection and residual cavity abscess formation; (iv) anaphylactic reaction and shock; (v) tear of surrounding tissues; (vi) hospital and post-operative length of stay (LOS); (vii) length of surgery; (viii) blood loss during surgery. Multivariable logistic/linear regression models with various adjustment strategies for confounders were performed to evaluate the association. RESULTS: A total of 128 hepatic CE patients were included with 82 (64.1%) and 46 (35.9%) receiving CS and RS, respectively. After fully adjusted, RS was associated with 60% lower risk of overall complication (aOR 0.4; 95%CI, 0.2-0.9) and 0.6-h shorter surgical time (aß 0.4; 95%CI,-0.0-0.8) comparing to CS. However, RS was associated with more blood loss during surgery (aß 179.3; 95%CI, 54.2-304.5). CONCLUSION: To conclude, RS was associated with a 60% reduction in developing overall complication in the short term, but may result in more blood loss during surgery than CS.

The geometric mean is a superior frequency response averaging method for human body vibration.

The frequency response data of human body vibration are often used for standardisation, design of transport vehicles and occupational health and safety measures. This article shows that the commonly used methods of averaging frequency response spectra, such as arithmetic averaging in the complex or magnitude domain and median averaging, are not as suitable as the less commonly used geometric averaging in the complex domain. This is because it is necessary to minimise the deviation of the measured values about the mean value and to minimise the bias from the true mean value due to noise, distortion and nonlinearity. Practitioner summary: For averaging frequency response spectra, it is necessary to minimise the bias from the true mean value. This research shows that the commonly used averaging methods, such as arithmetic averaging in the complex or magnitude domain and the median, are not as suitable as geometric averaging in the complex domain. Abbreviations: H1 Estimator: frequency response function estimation method using the cross-spectrum of the output with the input divided by the auto-spectrum of the input; ISO: International Organization for Standardization; NHK: Nippon Hatsujo Kabushiki Kaisha; PCB: PCB Group ("PCB" is abbreviation for "PicoCoulomB"); RMIT: Royal Melbourne Institute of Technology; r.m.s.: root mean square.