Applying augmented reality in teaching of surgical residents-telementoring, a "stress-free" way to surgical autonomy?

BACKGROUND: Achieving surgical autonomy can be considered the ultimate goal of surgical training. Innovative head-mounted augmented reality (AR) devices enable visualization of the operating field and teaching from remote. Therefore, utilization of AR glasses may be a novel approach to achieve autonomy. The aim of this pilot study is to analyze the feasibility of AR application in surgical training and to assess its impact on intraoperative stress. METHODS: A head-mounted RealWear Navigator® 500 glasses and the TeamViewer software were used. Initial "dry lab" testing of AR glasses was performed in combination with the Symbionix LAP Mentor™. Subsequently, residents performed various stage-adapted surgical procedures semi-autonomously (SA) (on-demand consultation of senior surgeon, who is in theatre but not scrubbed) versus permanent remote supervision (senior surgeon not present) via augmented reality (AR) glasses, worn by the resident in theatre. Stress was measured by intraoperative heart rate (Polar® pulse belt) and State-Trait Anxiety Inventory (STAI) questionnaire. RESULTS: After "dry lab" testing, N = 5 senior residents performed equally N = 25 procedures SA and with AR glasses. For both, open and laparoscopic procedure AR remote assistance showed satisfactory applicability. Utilization of AR significantly reduced intraoperative peak pulse rate from 131 to 119 bpm (p = 0.004), as compared with the semi-autonomous group. Likewise, subjectively perceived stress according to STAI was significantly lower in the AR group (p = 0.011). CONCLUSION: AR can be applied in surgical training and may help to reduce stress in theatre. In the future, AR has a huge potential to become a stepping stone to surgical autonomy.

Peripheral Artery Disease Leading to Major Amputation: Trends in Revascularization and Mortality Over 18 Years.

BACKGROUND: Patients with peripheral artery disease (PAD) are at risk for amputation. The aim of this study was to assess the type of revascularization prior to and the 30-day mortality rate after major amputation due to PAD. METHODS: Retrospective analysis of consecutive patients undergoing major amputation for PAD between 01/2000 and 12/2017 at a tertiary referral center. The number and target level of ipsilateral revascularizations prior to amputation were analyzed per patient and over the years. There were 3 types of revascularization (open, endovascular and combined treatment) at 3 levels: aortoiliac, femoropopliteal and infrapopliteal. Univariate and multivariate logistic regression models were used to assess the association of level of amputation and patient characteristics with 30-day mortality. RESULTS: A total of 312 patients (65.7% male) with a mean age of 73.3 ± 11 years underwent 338 major amputations: 70 (21%) above/through knee and 268 (79%) below knee. A median of 2 (interquartile range, IQR 1-4) revascularizations were performed prior to amputation, with a slight decrease of 1.4% per year from 2000-2017 (incidence rate ratio of 0.986 0.974-0.998; Poisson regression analysis, P = 0.021). 16% (53/338) of patients underwent primary amputation without revascularization; this number remained relatively stable throughout the study period. The proportion of exclusively open treatment before amputation decreased substantially from 35% in 2006 to none in 2016, while exclusively endovascular revascularizations were performed increasingly from 17% in 2002 to 64% in 2016. Amputation occurred after a median of 9.5 months (IQR 0.9-67.6 months) if the first revascularization was aortoiliac or femoropopliteal and after 2.1 months (IQR 0.5-13.8 months) if the first intervention was infrapopliteal (P < 0.001) with no significant change over the years (normal linear regression, P= 0.887). Thirty-day mortality was 8.9% (22/247) after below knee and 27.7% (18/65) after above/through knee amputation (adjusted OR 3.84, 95% CI 1.74-8.54, P= 0.001) with a slight increase of mortality over the study period (adjusted OR 1.09, 95% CI 1.018-1.159, Poisson regression analysis, P= 0.021). The uni- and multivariate analysis of patient characteristics did not show an association with mortality, except higher ASA classification (adjusted OR 2.65, 95% CI 1.23-5.72, P= 0.012). CONCLUSIONS: Mortality, especially after above/through knee amputation, remains high over the past 2 decades. There is a clear shift towards endovascular treatment of patients with PAD prior to major amputation. In patients needing infrapopliteal revascularizations, amputation was performed much sooner than in those with aortoiliac or femoropopliteal interventions, with no improvement over the years. Strategies to extend limb salvage in these patients should be the focus of further research.