413 - Robotic versus Thoracoscopic Lung Resection

“ resection ” OR “ lobectomy ” ] AND [ “ thoracic ” OR “ thoraco- scopic ” OR “ lung ” OR “ pulmonary ” ] AND [ “ robotic ” OR “ robot assisted ” OR “ da Vinci ” OR “ daVinci ” ]). No language restriction and no fi lters were applied. A total of 990 records were identi fi ed by the search. Only data of already published studies found through online research were used for meta-analysis, and we did not require the approval of the local ethics committee. Ten studies were selected for meta-analysis (listed in Table 1), all reporting lung resection (pneumonectomy, lobectomy, and segmentectomy) for either malign (lung cancer and metastatic foci) or benign lesions. Inclusion criteria were reporting of operation time, length of hospitalization, data ondrainage duration andmortality. Exclusion criteria were: (i) data not suitable for statistical analysis methods used for our analysis, (ii) reviews. Two people independently extracted data on number of cases, age and gender of patients, operation time, length of hospitaliza- tion, drainage duration, and mortality. Two studies used the same historical data for comparison. If not explicitly quoted, mean differences and P -values (based on t -tests) were used to obtain standard errors. [17,18,26] 2.2. Statistical analysis Random-effects models were used to combine data from different studies. [27,28] For continuous endpoints (operating time, hospitali- zation duration, and drainage duration), effect estimates and their standard errors were used, and mortality effects were compared by considering logarithmic odds ratios. In the case of zero counts in a contingency table, a value of 0.5 was added to all cells. [20] Heterogeneity between studies was estimated using the restricted maximum likelihood (REML) method, and combined effect estimates and associated con fi dence intervals were derived using the modi fi ed Knapp-Hartung approach. [29] Correlations between effect estimates due to the use of common data were accounted for by considering their covariance in the analysis. Computations were performed using R and the metafor package. [30,31] 3. Results 3.1. Study characteristics Nine retrospective, observational studies and 1 prospective cohort study published between 2011 and January 2016 were included in this analysis (see also Fig. 1). Study characteristics are listed in Table 1. A total of 3758 patients undergoing RVATS were compared with 58,677 patients experiencing VATS. Mean age of patients varied between 61 and 71 years for RVATS and 57 and 77 years for VATS. The number of patients included into these studies ranged from 17 to 2498 for RVATS and from 28 to 37,595 for VATS. If speci fi ed usually one surgeon or in the case of Adams et al 6 surgeons treated patients. Furthermore, Adams et al, Jang et al, Lee et al reported that the cases of RVATS published in these studies were fi rst case series while establishing RVATS as the new operation method. Patients were treated for lung cancer, metastatic foci, and benign lesions (Table 3). The mortality endpoint de fi nitions of studies included varied (refer also to Table 2). Although operation time, length of hospitaliza- tion, and chest were analyzed by these studies, we found no study reporting and evaluating pain or quality of life. Indication for operating patients was lung cancer, metastatic foci, or benign lesions. Only 2 studies [20,22] reported the number of lymph nodes removed and the number of lymph node stations dissected for both RVATS and VATS. Overall, the number of lymph nodes removed and lymph node stations dissected was similar (please refer to Table 3). Two studies utilized the same cohort of VATS patients (from a national database), [17,18] which common underlying data induces a positive correlation between the resulting estimates. This was accordingly accounted for which can be derived based on the group-speci fi c standard errors. 3.2. Operation time Six studies reported data on durations of surgery. The estimated mean differences in operating time are shown in Fig. 2. For RVATS, there are inconsistently reported longer operation times as well as shorter operation times. The combined effect estimate is at +8.97 minutes (95% con fi dence interval [ 28.12,+46.07]), indicating a slightly longer duration for RVATS. But, it is not signi fi cantly different from zero ( P = .56). The corresponding estimate of the between-study heterogeneity is at t = 34.7. 3.3. Duration of hospitalization Although we could not observe a signi fi cant difference in duration of hospital stay between the RVATS and the VATS group, at least a trend of shorter hospitalization became apparent in patients undergoing RVATS in the 6 studies analyzed. Figure 3 shows the data along with the combined estimate. The estimated difference in hospitalization time is at – 1.08 days (95%CI [ – 2.33, +0.17], P = .078) for RVATS. The between-study heterogeneity is estimated as t = 1.06. Table 1 Study characteristics (VATS/RVATS). N Age, y Females, % Data source Study Study type VATS RVATS VATS RVATS VATS RVATS VATS RVATS Jang et al [20] Restrospective observational 40 40 59.6 (10.1) 64.2 (9.9) 40.0 42.5 Original data Original data Kent et al [21] Restrospective observational 12427 430 66.3 ( – ) 67.2 ( – ) 55.8 55.6 State inpatient database State inpatient database Lee et al [22] Restrospective observational 34 35 77.0 ( – ) 71.0 ( – ) 76.5 37.1 Original data Original data Deen et al [23] Restrospective observational 58 57 65.0 ( – ) 68.0 ( – ) 63.8 66.7 Original data Original data Swanson et al [24] Restrospective observational 3818 335 66.3 ( – ) 66.4 ( – ) 54.7 52.5 Premier hospital database Premier hospital database Adams et al [18] Restrospective observational 4612 120 66.2 (11.3) 64.6 (10.5) 55.5 51.7 STS national database Original data, 6 centers Paul et al [19] Restrospective observational 37595 2498 67.0 ( – ) 68.0 ( – ) 56.8 51.6 Nationwide inpatient sample Nationwide inpatient sample Farivar et al [17] Restrospective observational 4612 181 66.2 (11.3) 64.8 (11.6) 55.5 58.0 STS national database Original data, 2 centers Demir et al [25] Prospective cohort 65 34 57.0 (14.0) 61.0 (15.0) 32.3 38.2 Original data Original data Mahieu et al [16] Retrospective observational 28 28 59 ( – ) 62 ( – ) 21.4 32.1 Original data Original data RVATS = robot-assisted minimally invasive surgery, VATS = video- assisted minimally invasive surgery. Emmert et al. Medicine (2017) 96:35 Medicine 2 | The Surgical Technologist | MAY 2018 208