Presentation
Ergonomic Evaluation of Robotic Nipple-Sparing Mastectomy: Workload and Usability Comparison Between Multi-Port da Vinci Xi and Single-Port da Vinci SP Systems
SessionSurgery (HE6)
DescriptionNipple-sparing mastectomy (NSM) is a conservative mastectomy that provides an aesthetically pleasing cosmetic outcome without compromising the integrity of a mastectomy or breast reconstruction (Galimberti et al., 2017). Despite the patient benefits, NSM has some drawbacks concerning surgeon satisfaction and effectiveness of operating. NSM is more demanding on surgeons as compared to other mastectomies due to the added goal of preserving the nipple-areola complex leading to high fatigue levels (Jackson et al., 2017). A recent study conducted by Hallbeck et al. (2020) reported that surgeons rated NSM procedures to be 23% more physically demanding than skin sparing mastectomy (SSM) procedures. A potential solution to address some of these challenges may be robot-assisted NSM (R-NSM) as it widens the operating space such that surgeons have better visibility of breast tissue and the specific incision point -granting surgeons easier access to the more difficult-to-reach tumors (Selber, 2019). Furthermore, it eliminates the need for deep retractions, as seen with open NSM, and allows for a more consistent working distance and potential for better postures for surgeons (Selber, 2019). R-NSM’s main purpose is to enhance visibility for surgeons to achieve superior technical and cosmetic results for patient satisfaction (Toesca et al., 2019; 2021). A recent study conducted by Toesca et al. (2021) found that open NSM and R-NSM had no significant differences in peri-operative complications and R-NSM significantly improved the quality of life of patients.
Two well-known robotic systems for robotic assisted surgeries are multi-port da Vinci Xi (MP) and single-port da Vinci SP (SP). The MP system is designed to have four arms, each housing specific instrument(s), while the SP system is housing all three multijointed instruments and a 3D HD 360° camera in a single 25mm trocar (Intuitive Surgical Inc., 2018). This compact set-up reduces obtrusion for bedside assistance and eliminates the need for surgeons to switch between camera angle to obtain holistic views of the surgical field as in the MP system. As with most advancements in medical technology, the focus of research for widespread adaptation of new technologies and techniques are focused on patient safety and surgical outcomes with little to no attention on the interaction between the technology and the surgeon or surgical team. For successful adaptation of the MP and SP system for R-NSM, there is the need to expand research to address issues relating to the interaction between the surgeon, and this new technology. Thus, the main goal of this study was to quantify and compare the workload and usability aspects of MP and SP systems during NSM surgical procedures considering the potential effects of learning curve.
This study was approved by the Institutional Review Board (IRB). One attending breast surgeons (female) from a quaternary academic hospital system (Midwest) in the United States participated in the study. The surgeon started performing R-NSM using the MP system and after performing 26 R-NSM cases, started using the SP system. To capture the potential effects of learning curve in performing R-NSM, the first 5 R-NSM cases using MP system (from the first 6 cases- 1 missed case in the data collection) were grouped representing surgeon’s early performance experience period R-NSM procedures (R-START). The last five (cases 22-26) R-NSM cases using the MP system (R-MP) and the first five R-NSM cases using the SP system (R-SP) were also categorized as groups. All the R-NSM surgical procedures in this study were bilateral and were performed using a single modality approach for both left and right breasts and none of them was a cancer case. After each surgical procedure the surgeon was sent an electronic survey via her institutional email address. The survey was designed and conducted using Qualtrics (Qualtrics, Provo, UT). The surgeon was asked to complete the survey within 48 hours from the completion of the NSM surgical procedure. The survey investigated surgeon’s intraoperative workload based on Surgical-Task Load Index (SURG-TLX) (Wilson et al., 2011) including mental demand, physical demand, temporal demand, performance, effort, frustration, distractions, degree of difficulty, and overall fatigue from “0” (minimum value) to “20” (maximum value) using a visual analog scale (VAS). It should be clarified that for the performance, “0” meant “Failure” and “20” was “Perfect”. The survey also recorded surgeon’s feedback on the robot including feeling efficient and feeling precise in maneuvering the surgical instruments and maneuvering the camera and feeling confident in overall use of the robot; all on a five-level Likert scale (from strongly agree to strongly disagree). Additionally, the potential effects of different parts of the robot on surgical workflow and distractions were recorded.
The patients’ details were breast cup size of A = 2 cases, B = 6 cases, C = 7 cases, breast ptosis of grade 0 = 3 cases, grade 1 = 6 cases, grade 2 = 4 cases, grade 4 = 1 case (1 missing data point), and BMI (kg/m2) of <18.5 = 1 case, 18.5-24.9 = 8 cases, and 25.0-29.9 = 6 cases. Overall, the median and interquartile range (IQR) of workload subscales for the 15 R-NSM surgical procedures were mental demand = 5.0 (2.0), physical demand = 3.0 (3.0), temporal demand 3.0 (1.0), performance (greater score is better) = 17.0 (2.0), effort = 4.0 (3.0), frustration = 2.0 (1.0), distractions = 3.0 (1.0), degree of difficulty = 10.0 (5.0), and fatigue = 3.0 (2.0). The usability questions about feeling efficient and precise in maneuvering the surgical instruments and camera and feeling confident in overall use of the robot were all either “strongly agree” or “agree”. The statistical analysis using non-parametric Kruskal-Wallis test and Wilcoxon Signed-Rank test (post-hoc pairwise comparisons) revealed that “effort” was significantly higher for R-START cases (median = 8.0, IQR = 5.5) compared to R-MP (median = 4.0, IQR = 2.0, p = 0.0339) and R-SP (median = 4.0, IQR = 1.5, p = 0.0406). The rest of the investigated variables did not show significant differences among the three compared conditions (R-START, R-MP, and R-SP). Finally, during one of the R-START cases hand/finger grip was reported as a reason for distraction from surgery.
Interpreting the workload subscales could be more straightforward if there was a distinct level directly affecting patient safety and surgeon health. Due to the complexity of the surgical team and human capabilities, such a threshold is not easily determined. Previous literature, however, utilizes a threshold score above 50% to indicate levels of concern (Yu et al., 2016). The results of our study showed that “degree of difficulty” (all three conditions) and “effort” (R-START) were the workload subscales that require high levels of attention (over or close to the threshold of 50%). While there is always room for improving workload subscales, the next step of this study should focus on investigating the potential underlying reasons for high “effort” and “degree of difficulty” ratings (e.g., interviewing the surgeon, conducting more data collections with new participants). It should be noted that this study is based on survey responses from one breast surgeon in an FDA trial, which limits the generalizability of our findings. Considering these limitations, the data suggests that both MP and SP systems are overall acceptable to the surgeon based on measured usability aspects. Finally, the results suggest that there is a learning curve regarding the surgeon’s “effort” in performing R-NSM, which could be a multifaceted phenomenon with underlying reasons including both the surgical team and the surgeon. Future studies should focus on examining these potential factors to develop recommendations for the robot designers, surgical ergonomists, surgeons and surgical teams regarding R-NSM surgical procedures.
References will be provided per request.
Two well-known robotic systems for robotic assisted surgeries are multi-port da Vinci Xi (MP) and single-port da Vinci SP (SP). The MP system is designed to have four arms, each housing specific instrument(s), while the SP system is housing all three multijointed instruments and a 3D HD 360° camera in a single 25mm trocar (Intuitive Surgical Inc., 2018). This compact set-up reduces obtrusion for bedside assistance and eliminates the need for surgeons to switch between camera angle to obtain holistic views of the surgical field as in the MP system. As with most advancements in medical technology, the focus of research for widespread adaptation of new technologies and techniques are focused on patient safety and surgical outcomes with little to no attention on the interaction between the technology and the surgeon or surgical team. For successful adaptation of the MP and SP system for R-NSM, there is the need to expand research to address issues relating to the interaction between the surgeon, and this new technology. Thus, the main goal of this study was to quantify and compare the workload and usability aspects of MP and SP systems during NSM surgical procedures considering the potential effects of learning curve.
This study was approved by the Institutional Review Board (IRB). One attending breast surgeons (female) from a quaternary academic hospital system (Midwest) in the United States participated in the study. The surgeon started performing R-NSM using the MP system and after performing 26 R-NSM cases, started using the SP system. To capture the potential effects of learning curve in performing R-NSM, the first 5 R-NSM cases using MP system (from the first 6 cases- 1 missed case in the data collection) were grouped representing surgeon’s early performance experience period R-NSM procedures (R-START). The last five (cases 22-26) R-NSM cases using the MP system (R-MP) and the first five R-NSM cases using the SP system (R-SP) were also categorized as groups. All the R-NSM surgical procedures in this study were bilateral and were performed using a single modality approach for both left and right breasts and none of them was a cancer case. After each surgical procedure the surgeon was sent an electronic survey via her institutional email address. The survey was designed and conducted using Qualtrics (Qualtrics, Provo, UT). The surgeon was asked to complete the survey within 48 hours from the completion of the NSM surgical procedure. The survey investigated surgeon’s intraoperative workload based on Surgical-Task Load Index (SURG-TLX) (Wilson et al., 2011) including mental demand, physical demand, temporal demand, performance, effort, frustration, distractions, degree of difficulty, and overall fatigue from “0” (minimum value) to “20” (maximum value) using a visual analog scale (VAS). It should be clarified that for the performance, “0” meant “Failure” and “20” was “Perfect”. The survey also recorded surgeon’s feedback on the robot including feeling efficient and feeling precise in maneuvering the surgical instruments and maneuvering the camera and feeling confident in overall use of the robot; all on a five-level Likert scale (from strongly agree to strongly disagree). Additionally, the potential effects of different parts of the robot on surgical workflow and distractions were recorded.
The patients’ details were breast cup size of A = 2 cases, B = 6 cases, C = 7 cases, breast ptosis of grade 0 = 3 cases, grade 1 = 6 cases, grade 2 = 4 cases, grade 4 = 1 case (1 missing data point), and BMI (kg/m2) of <18.5 = 1 case, 18.5-24.9 = 8 cases, and 25.0-29.9 = 6 cases. Overall, the median and interquartile range (IQR) of workload subscales for the 15 R-NSM surgical procedures were mental demand = 5.0 (2.0), physical demand = 3.0 (3.0), temporal demand 3.0 (1.0), performance (greater score is better) = 17.0 (2.0), effort = 4.0 (3.0), frustration = 2.0 (1.0), distractions = 3.0 (1.0), degree of difficulty = 10.0 (5.0), and fatigue = 3.0 (2.0). The usability questions about feeling efficient and precise in maneuvering the surgical instruments and camera and feeling confident in overall use of the robot were all either “strongly agree” or “agree”. The statistical analysis using non-parametric Kruskal-Wallis test and Wilcoxon Signed-Rank test (post-hoc pairwise comparisons) revealed that “effort” was significantly higher for R-START cases (median = 8.0, IQR = 5.5) compared to R-MP (median = 4.0, IQR = 2.0, p = 0.0339) and R-SP (median = 4.0, IQR = 1.5, p = 0.0406). The rest of the investigated variables did not show significant differences among the three compared conditions (R-START, R-MP, and R-SP). Finally, during one of the R-START cases hand/finger grip was reported as a reason for distraction from surgery.
Interpreting the workload subscales could be more straightforward if there was a distinct level directly affecting patient safety and surgeon health. Due to the complexity of the surgical team and human capabilities, such a threshold is not easily determined. Previous literature, however, utilizes a threshold score above 50% to indicate levels of concern (Yu et al., 2016). The results of our study showed that “degree of difficulty” (all three conditions) and “effort” (R-START) were the workload subscales that require high levels of attention (over or close to the threshold of 50%). While there is always room for improving workload subscales, the next step of this study should focus on investigating the potential underlying reasons for high “effort” and “degree of difficulty” ratings (e.g., interviewing the surgeon, conducting more data collections with new participants). It should be noted that this study is based on survey responses from one breast surgeon in an FDA trial, which limits the generalizability of our findings. Considering these limitations, the data suggests that both MP and SP systems are overall acceptable to the surgeon based on measured usability aspects. Finally, the results suggest that there is a learning curve regarding the surgeon’s “effort” in performing R-NSM, which could be a multifaceted phenomenon with underlying reasons including both the surgical team and the surgeon. Future studies should focus on examining these potential factors to develop recommendations for the robot designers, surgical ergonomists, surgeons and surgical teams regarding R-NSM surgical procedures.
References will be provided per request.
Event Type
Oral Presentations
TimeTuesday, April 12:37pm - 3:00pm EDT
LocationHarbour C
Hospital Environments (HE)